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Sample records for 188re 177lu 51cr

  1. Monte Carlo Calculation of Radioimmunotherapy with 90Y-, 177Lu-, 131I-, 124I-, and 188Re-Nanoobjects: Choice of the Best Radionuclide for Solid Tumour Treatment by Using TCP and NTCP Concepts

    S. Lucas

    2015-01-01

    Full Text Available Radioimmunotherapy has shown that the use of monoclonal antibodies combined with a radioisotope like 131I or 90Y still remains ineffective for solid and radioresistant tumour treatment. Previous simulations have revealed that an increase in the number of 90Y labelled to each antibody or nanoobject could be a solution to improve treatment output. It now seems important to assess the treatment output and toxicity when radionuclides such as 90Y, 177Lu, 131I, 124I, and 188Re are used. Tumour control probability (TCP and normal tissue complication probability (NTCP curves versus the number of radionuclides per nanoobject were computed with MCNPX to evaluate treatment efficacy for solid tumours and to predict the incidence of surrounding side effects. Analyses were carried out for two solid tumour sizes of 0.5 and 1.0 cm radius and for nanoobject (i.e., a radiolabelled antibody distributed uniformly or nonuniformly throughout a solid tumour (e.g., Non-small-cell-lung cancer (NSCLC. 90Y and 188Re are the best candidates for solid tumour treatment when only one radionuclide is coupled to one carrier. Furthermore, regardless of the radionuclide properties, high values of TCP can be reached without toxicity if the number of radionuclides per nanoobject increases.

  2. Radiopharmaceuticals based on 177LU for radionuclide therapy. Development of labeling procedures and Quality control methods

    The cancer in Cuba constitutes a fundamental problem of health and it occupies the second place as cause of death. It is known that the use of labeled biomolecules (like monoclonal antibodies-mAb- and peptides) with radioisotopes has become a viable and promissory alternative for the cancer. The monoclonal antibodies production in Cuba for different uses enjoys national and international prestige. Some years ago, the Center of Molecular Immunology (CIM) and the Isotope Center (CENTIS) joined efforts to develop the applications of the Cuban monoclonal antibodies. Different clinical trials have been carried out to explore the possibilities of the radioimmunotherapy in humans using monoclonal antibodies. We have been developed different radiopharmaceuticals based on monoclonal antibodies labeled with β emitters (131I, 188Re and 90Y). Because of 177Lu is one of the isotopes emerging as a clear choice for therapy, we expect that we can develop a 177Lu radiopharmaceutical based on h-R3 monoclonal antibody (Nimotuzumab). DOTA-conjugated monoclonal antibody could be radiolabelled with 177Lu with high yields, however our main focus will be to further optimize radiolabelling conditions to avoid side reactions. Labeling yields using different DOTA derivatives (DOTA-NHS, DOTA-SCN) were higher than 90%. Quality control evaluation was performed by HPLC and ITLC-SG. . (Author)

  3. Optimization of the preparation and quality control of 177Lu based therapeutic radiopharmaceuticals: Facilities available at PINSTECH

    Isotope Production Division (IPD) at Pakistan Institute of Nuclear Science and Technology (PINSTECH) has established centralized facilities for bulk production of radiopharmaceuticals to be supplied to various nuclear medical centers of the country. Here different groups have been established to look after the production of 99mTc generators, production of sodium iodide (131I) solution and other reactor produced radionuclides; radiopharmaceuticals freeze dried in-vivo diagnostic kits, quality control of radiopharmaceuticals and their dispatch. For this purpose different laboratories including two clean laboratories; one for bulk production of freeze dried in-vivo diagnostic kits and other for 99mTc generators were provided by the IAEA under technical cooperation, have been constructed. Organic laboratory has also been created for synthesis of MAG-3, MIBI, DISIDA, HMPAO, ECD etc. Excellent quality control laboratories have also been established for checking every batch in terms of radionuclidic purity, radiochemical purity, sterility, pyrogenicity and biodistribution in animals. Research activities under IAEA coordinated research programmes related to preparation of therapeutic β-particle emitting radionuclides like 177Lu, 166Ho, 153Sm, 186,188Re etc in PARR-I research reactor and their radiopharmaceuticals formulations with HEDP, EDTMP, FHMA, DOTATATE were also carried out. Studies on the optimization of the production of 177Lu radionuclide by irradiating natural/enriched lutetium targets as solid or liquid in PARR-I reactor for different time intervals were carried out. The irradiation data indicate that specific activity of liquids targets (5.5 Ci/mg) is higher than solid targets (4.6 Ci/mg). Studies on the optimization of 177Lu-EDTMP and 177Lu-DOTA-Tyr3-Octreotate complexes were investigated w.r.t. pH, temperature and incubation period to get a complex of high yield (>99%). Radiochemical purity of 177Lu-DOTA-Tyr3-Octreotate was determined by radio TLC technique

  4. Absorbed dose assessment of 177Lu-zoledronate and 177Lu-EDTMP for human based on biodistribution data in rats

    Yousefnia, Hassan; Zolghadri, Samaneh; Jalilian, Amir Reza

    2015-01-01

    Over the past few decades, several bone-seeking radiopharmaceuticals including various bisphosphonate ligands and β-emitting radionuclides have been developed for bone pain palliation. Recently, 177Lu was successfully labeled with zoledronic acid (177Lu-ZLD) as a new generation potential bisphosphonate and demonstrated significant accumulation in bone tissue. In this work, the absorbed dose to each organ of human for 177Lu-ZLD and 177Lu-ethylenediaminetetramethylene phosphonic acid (177Lu-EDT...

  5. Production of 177Lu for targeted radionuclide therapy: Available options

    This review provides a comprehensive summary of the production of 177Lu to meet expected future research and clinical demands. Availability of options represents the cornerstone for sustainable growth for the routine production of adequate activity levels of 177Lu having the required quality for preparation of a variety of 177Lu-labeled radiopharmaceuticals. The tremendous prospects associated with production of 177Lu for use in targeted radionuclide therapy (TRT) dictate that a holistic consideration should evaluate all governing factors that determine its success. While both “direct” and “indirect” reactor production routes offer the possibility for sustainable 177Lu availability, there are several issues and challenges that must be considered to realize the full potential of these production strategies. This article presents a mini review on the latest developments, current status, key challenges and possibilities for the near future. A broad understanding and discussion of the issues associated with 177Lu production and processing approaches would not only ensure sustained growth and future expansion for the availability and use of 177Lu-labeled radiopharmaceuticals, but also help future developments

  6. Preparation and biological assessment of 177Lu-BPAMD as a high potential agent for bone pain palliation therapy. Comparison with 177Lu-EDTMP

    In this study, 177Lu-(4-{[(bis(phosphonomethyl))- carbamoyl]methyl}-7,10-bis(carboxymethyl)-1,4,7,10-tetraazacyclododec-1-yl) acetic acid (177Lu-BPAMD) was successfully prepared. The quality control, partition coefficient, hydroxyapatite binding assay and stability of the complex were determined. For better comparison, biodistribution patterns of 177Lu-BPAMD and 177Lu-EDTMP complexes were compared in same animal model. 177Lu-BPAMD was prepared with high radiochemical purity ([93 %) and specific activity of 534 GBq/mmol at the optimal conditions. Comparative study between 177Lu-BPAMD and 177Lu-EDTMP indicated higher bone uptake and lesser accumulation in the other organs for 177Lu-BPAMD. 177Lu-BPAMD can be considered as a promising agent for bone pain palliation in the near future. (author)

  7. Comparison of [177Lu-DOTA0,Tyr3]octreotate and [177Lu-DOTA0,Tyr3]octreotide: which peptide is preferable for PRRT?

    Patients with somatostatin receptor subtype 2-positive metastasised neuroendocrine tumours can be treated with [177Lu-DOTA0,Tyr3]octreotate. Some use octreotide as the peptide for peptide receptor radionuclide therapy (PRRT). We compared in seven patients [177Lu-DOTA0,Tyr3]octreotide (177Lu-DOTATOC) and [177Lu-DOTA0,Tyr3]octreotate (177Lu-DOTATATE), to see which peptide should be preferred for PRRT with 177Lu. In the same patients, 3,700 MBq 177Lu-DOTATOC and 3,700 MBq 177Lu-DOTATATE was administered in separate therapy sessions. Amino acids were co-administered. Whole-body scanning was performed on days 1, 4 and 7 post therapy. Blood and urine samples were collected. We calculated residence times for tumours, spleen and kidneys. All patients had longer residence times in spleen, kidneys and tumours after use of 177Lu-DOTATATE (p=0.016 in each case). Comparing 177Lu-DOTATATE with 177Lu-DOTATOC, the mean residence time ratio was 2.1 for tumour, 1.5 for spleen and 1.4 for kidneys. Dose-limiting factors for PRRT are bone marrow and/or kidney dose. Although the residence time for kidneys was longer when using 177Lu-DOTATATE, the mean administered dose to tumours would still be advantageous by a factor of 1.5, assuming a fixed maximum kidney dose is reached. Plasma radioactivity after 177Lu-DOTATATE was comparable to that after 177Lu-DOTATOC. Urinary excretion of radioactivity was comparable during the first 6 h; thereafter there was a significant advantage for 177Lu-DOTATOC. 177Lu-DOTATATE had a longer tumour residence time than 177Lu-DOTATOC. Despite a longer residence time in kidneys after 177Lu-DOTATATE, tumour dose will always be higher. Therefore, we conclude that the better peptide for PRRT is octreotate. (orig.)

  8. Production logistics and possible applications of 177Lu

    Owing to the favourable decay characteristics, 177Lu can be considered as an attractive radionuclides for various therapeutic applications. Different methodologies of its production, their comparative evaluation along with its possible applications have been described. (author)

  9. Production logistics of 177Lu for radionuclide therapy

    Owing to its favourable decay characteristics 177Lu [T1/2=6.71 d, Eβ(max)=497 keV] is an attractive radionuclide for various therapeutic applications. Production of 177Lu using [176Lu (n,γ)177Lu] reaction by thermal neutron bombardment on natural as well as enriched lutetium oxide target is described. In all, ∼4 TBq/g (108 Ci/g) of 177Lu was obtained using natural Lu target after 7 d irradiation at 3x1013 n/cm2/s thermal neutron flux while it was ∼110 TBq/g (3000 Ci/g) of 177Lu when 60.6% enriched 176Lu target was used. In both the cases, radionuclidic purity was ∼100%, only insignificant quantity of 177mLu [T1/2=160.5 d, Eβ(max)=200 keV] could be detected as the radionuclidic impurity. Production logistics using different routes of production is compared. Possible therapeutic applications of 177Lu are discussed and its merits highlighted by comparison with other therapeutic radionuclides

  10. radiolabeling of DOTA-substance P with 177Lu and biodistribution of 177Lu-DOTA-substance P

    The aim of this project is to evaluate the biodistribution of 177Lu-DOTA-SP in normal mice and in PANC-1 tumor bearing nude mice and to pave the way for its potentially medical application. In this study, 177Lu-DOTA-SP was successfully prepared with labeling yield of greater than 90% at optimized conditions and more than 98% of radiochemical purity after C18 Sep-Pak purification. 177Lu-DOTA-SP showed good stability in saline and in 5% serum while it decomposed slowly in 10% serum. Biodistribution studies in normal mice showed high uptake of 177Lu-DOTA-SP in the kidneys, indicating the excretion mainly by renal pathway. In addition, 177Lu-DOTA-SP was washed out from the blood quickly. Bio- distribution of 177Lu-DOTA-SP in PANC-1 tumor bearing mice showed higher uptake in pancreatic tumor than that in normal pancreas, indicating the presence of NK-1 receptors in PANC-1 pancreatic tumor. However, from SPECT image, no radioactivity accumulation was observed in PANC-1 tumor. Further evaluation is needed to confirm its potential application for radiotherapy of pancreatic cancers. (authors)

  11. Production of 186Re and 188Re, and synthesis of 188Re-DTPA

    Production of radioactive rhenium isotopes 186Re and 188Re, and synthesis of 188Re-DTPA have been studied. For 186Re, a production method by the 185Re(n, γ) 186Re reaction in a reactor has been established. For 188Re, a production method by the double neuron capture reaction of 186W, which produces a 188W/188Re generator, has been established. For synthesis of 188Re-DTPA, the optimum conditions, including pH, the amounts of regents and so on, have been determined. (author)

  12. Dosimetric Studies in Normal Mice of 177Lu-DOTA-SP and 177Lu-DOTA-His2-MG

    DOTA-Substance-P (SP) and DOTA-minigastrin (His2-MG) labeled with 177Lu could be used in peptide receptor radionuclide therapy (PRRT) for treatment of various tumour species. Biodistribution studies of both radiopharmaceuticals in normal mice were performed at different times. Absorbed doses in mouse organs were estimated and extrapolated to humans. Dosimetric calculations showed that kidneys received the highest dose, for both radiopharmaceuticals. The Maximum Tolerated Activity (MTA) of 177Lu-DOTA-SP that can be administered without kidney toxicity are 414 and 422 MBq/kg for the standard adult man and woman, respectively. In the same way, the MTA of 177Lu-DOTA-His2-MG are 488 and 518 MBq/kg for the standard adult man and woman, respectively. (authors)

  13. Preparation of 177Lu-DTPA-BIS-BIOTIN and biodistribution evaluation in normal mice

    The labeling method for 177Lu-DTPA-BIS-BIOTIN was established, and the biodistribution of 177Lu-DTPA-BIS-BIOTIN in normal mice was carried out as well. Under the optimal experimental condition (DTPA-BIS-BIOTIN 25 μg, pH=4.5 reacting at 80 degree C for 20 min), the labeling yield of 177Lu-DTPA-BIS-BIOTIN is more than 99.0%. 177Lu-DTPA-BIS-BIOTIN shows pretty good in vitro stability. The biodistribution of 177Lu-DTPA-BIS-BIOTIN in normal mice shows a rapid blood clearance. The uptake of 177Lu-DTPA-BIS-BIOTIN is mainly accumulated in liver, spleen and kidney. 177Lu-DTPA-BIS-BIOTIN is excreted by kidney. The results provide the basis for further study on 177Lu-DTPA-BIS-BIOTIN used in pretargeted radioimage and radiotherapy of cancer. (authors)

  14. Preparation and Biodistribution Evaluation in Mice of ~(177)Lu-DOTA-TOC

    2011-01-01

    The study of 177Lu labeled radiopharmaceuticals for cancer therapy is fast emerging as an important part of nuclear medicine. 177Lu-labelling of DOTA derivatized peptide DOTA-TOC (Tyr3-Octreotide) was carried out and biodistribution of 177Lu-DOTA-TOC in normal

  15. Studies of HEDP labelled with 188Re from different generators of 188W /188Re

    The widespread interest in 188Re for therapeutic applications, is due to its attractive 16,9 hours half-life, emission of a β- particle with maximum energy of 2.12 MeV and gamma-ray of 155 keV suitable for imaging. This work presents the radiolabelling of HEDP (etidronate) with 188Re eluted from alumina-based 188W/188Re generators and tungstate-based 188W/188Re gel generators. Dependence of the yield of the 18'8Re-HEDP on the concentration of the reduction agent, p H, reaction time, temperature and addition of carrier Re2O7 were evaluated. The radiolabelling of 188Re-HEDP procedure using the optimum conditions resulted a yield >= 98% for liquid and lyophilized kits. This basic formulation contains: 30 mg de HEDP, 7 mg de SnCl2, 3 mg de ascorbic acid and addition of 20 mug of Re2O7. The reactions were carried out with heating in boiling water for 30 minutes followed by 60 minutes of incubation. Another important aspect of this work was the radiochemical quality control comparing the results of PC, TLC and ion chromatography, along with the experiments with HPLC. The biological distribution proved the adequate bone uptake and in vivo stability of 188Re-HEDP complexes. (author)

  16. Biodistribution and Dosimetry of 177Lu-tetulomab, a New Radioimmunoconjugate for Treatment of Non-Hodgkin Lymphoma

    Repetto-Llamazares, Ada H. V.; Larsen, Roy H.; Mollatt, Camilla; Lassmann, Michael; Dahle, Jostein

    2013-01-01

    The biodistribution of the anti-CD37 radioimmunoconjugate 177Lu-tetraxetan-tetulomab (177Lu-DOTA-HH1) was evaluated. Biodistribution of 177Lu-tetraxetan-tetulomab was compared with 177Lu-tetraxetan-rituximab and free 177Lu in nude mice implanted with Daudi lymphoma xenografts. The data showed that 177Lu-tetulomab had a relevant stability and tumor targeting properties in the human lymphoma model. The half-life of 177Lu allowed significant tumor to normal tissue ratios to be obtained indicatin...

  17. Biokinetic study of free 177Lu in NIH mice

    Full text: 177Lu has been identified, by the scientific community, as a radionuclide with interesting advantages compared with 90Y and other beta emitters used in nuclear medicine. This paper analyses the free 177Lu biokinetic behavior in NIH male mice from activity measurements performed by the Radiopharmacy Division of CNEA (Comision Nacional de Energia Atomica) in the frame of an IAEA (International Atomic Energy Agency) Coordinated Research Project. The study of experimental data is a previous condition that allows drawing the activity-time curves for organs and to know the biodistribution of 177Lu. The cumulated activity in organs of interest in NIH male mice are calculated and critical organs are identified. The organs selected for analysis in this paper are the liver, kidneys, spleen, stomach, intestine, lungs, skeleton and red marrow. The last one is estimated from the activity measured in blood based on a recognized method published by Sgouros (2000). The results has been extrapolated to human assuming the same biokinetic behaviour as mice being the applicability of the different extrapolation methods also discussed. The direct extrapolation from mice data was the method of election from a radiological protection point of view. The measurement procedures, the data processing, the extrapolation techniques and the analysis performed in this study will contribute as a basis for future research of this group in the area of antibodies and other radiopharmaceutical labeled with 177Lu. The cumulated activity calculated in each organ is relevant because it makes possible to perform the dose assessment through the application of appropriate dose coefficients. It is a necessary step in order to evaluate the toxicity risk that is required in a pre-clinical study. (author)

  18. Method for preparing high specific activity 177Lu

    Mirzadeh, Saed; Du, Miting; Beets, Arnold L.; Knapp, Jr., Furn F.

    2004-04-06

    A method of separating lutetium from a solution containing Lu and Yb, particularly reactor-produced .sup.177 Lu and .sup.177 Yb, includes the steps of: providing a chromatographic separation apparatus containing LN resin; loading the apparatus with a solution containing Lu and Yb; and eluting the apparatus to chromatographically separate the Lu and the Yb in order to produce high-specific-activity .sup.177 Yb.

  19. Preliminary studies on /sup 177/Lu-labeled pyrophosphate (/sup 177/Lu-pyp) as a potential bone-seeking radiopharmaceutical for bone pain palliation

    /sup 99m/Tc-Sn-PYP (Technetium-99m labeled tin pyrophosphate) has been widely used as a radiopharmaceutical for bone scanning as well as in nuclear cardiology. It is also found in the body in trace amounts. /sup 177/Lu is presently considered as an excellent radionuclide for developing bone pain palliation agents. PYP is an analogue of MDP and MDP has been labeled with /sup 177/Lu. No study on preparing a complex of /sup 177/Lu with PYP has been reported yet. Based on these facts, it was hypothesized that a bone-seeking /sup 177/Lu -PYP (Lutetium-177 labeled Pyrophosphate) radiopharmaceutical could be developed as an agent for palliative radiotherapy of bone pain due to skeletal metastases. Bio evaluation studies with rabbit under gamma-camera after intravenous injection of /sup 177/Lu- PYP complex in rabbit may yield important information to assess its potential for clinical use as a bone- pain palliation agent for the treatment of bone metastases. /sup 177/Lu was produced by irradiating lutetium foil (11 mg) natural target at a flux approx. equal to 1. 1014 n/cm/sup 2//s for 12 h in the swimming pool type reactor. /sup 177/Lu was labeled with PYP by adding nearly 37 MBq (1.0 mCi) of /sup 177/LuCl/sub 3/ to a vial containing 28 mg Na-PYP (Sodium pyrophosphate). The radiochemical purity and labeling efficiencies were determined by paper chromatography with Whatman 3MM paper using Ammonium Hydroxide:Methanol:Water (1:20:20) as mobile phase. Labeling of /sup 177/Lu with PYP was optimized and a labeled sample was subjected to HPLC analysis. To determine the charge on the /sup 177/Lu-PYP complex, radio-electrophoresis was conducted for 1 hour under a voltage of 300 V and 45 mA current using 0.025 M phosphate buffer (pH 6.9). Bio evaluation studies with rabbit under ?-camera were also performed to verify the skeletal uptake. The quality control using paper radio-chromatography has shown>99% radiochemical purity of /sup 177/Lu-PYP complex. Radio-chromatography also

  20. Preparation of 188Re complexes for nuclear medicine

    Synthesis conditions for 188Re complexes without carrier and with methylenediphosphonic, 1-hydroxyethylenediphosphonic and dimercaptosuccinic acids are studied 188Re is produced using 188W/188Re generator. Tin dichloride is used for rhenium reduction and ascorbic acid is taken as antioxidant. Effect of reducer concentration, p H, process duration, antioxidant nature, temperature and carrier introduction on the complex yield is investigated. Under the optimal conditions the yield makes up over 95% both for 188Re with and without carrier. The complex stability in relation to p H and salt background change is studied

  1. Production of {sup 177}Lu for targeted radionuclide therapy: Available options

    Dah, Ashutosh [Isotope Production and Applications Division, Bhabha Atomic Research Centre (BARC), Mumbai (India); Pillai, Maroor Raghavan Ambikalmajan [Molecular Group of Companies. Kerala (India); Knapp, Furn F. Jr. [Medical Isotopes Program, Isotope Dept. Group, Oak Ridge National Laboratory (ORNL), Oak Ridge (United States)

    2015-06-15

    This review provides a comprehensive summary of the production of {sup 177}Lu to meet expected future research and clinical demands. Availability of options represents the cornerstone for sustainable growth for the routine production of adequate activity levels of {sup 177}Lu having the required quality for preparation of a variety of {sup 177}Lu-labeled radiopharmaceuticals. The tremendous prospects associated with production of {sup 177}Lu for use in targeted radionuclide therapy (TRT) dictate that a holistic consideration should evaluate all governing factors that determine its success. While both “direct” and “indirect” reactor production routes offer the possibility for sustainable {sup 177}Lu availability, there are several issues and challenges that must be considered to realize the full potential of these production strategies. This article presents a mini review on the latest developments, current status, key challenges and possibilities for the near future. A broad understanding and discussion of the issues associated with {sup 177}Lu production and processing approaches would not only ensure sustained growth and future expansion for the availability and use of {sup 177}Lu-labeled radiopharmaceuticals, but also help future developments.

  2. Synthesis of {sup 188}Re-DMSA complex using carrier-free {sup 188}Re

    Hashimoto, Kazuyuki; Izumo, Mishiroku [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Islam, M.S.

    1997-03-01

    The synthesis of rhenium-DMSA labelled compound using carrier-free {sup 188}Re from the {sup 188}W/{sup 188}Re generator has been carried out. Stannous chloride was used as the reducing agent for reduction of rhenium and ascorbic acid was used as an antioxidant in the reaction media. The dependence of the yield of Re-DMSA complex upon the concentration of reducing agent, pH, reaction time, anti-oxidant, carrier and temperature was investigated. Under optimum conditions, the yield of Re-DMSA complexes were more than 98% for the carrier-free as well as carrier-added {sup 188}Re. The stability of the Re-DMSA complexes at different pH and time were also investigated. It was found that the Re-DMSA complex was very stable and did not undergo any changes or decomposition with the changes of pH from its initial values even after 48 hours of pH change for carrier-free as well as carrier-added complexes. (author)

  3. Comparison of [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate and [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotide: which peptide is preferable for PRRT?

    Esser, J.P. [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands); Medisch Spectrum Twente, Department of Nuclear Medicine, Enschede (Netherlands); Krenning, E.P.; Teunissen, J.J.M.; Kooij, P.P.M.; Gameren, A.L.H. van; Bakker, W.H.; Kwekkeboom, D.J. [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands)

    2006-11-15

    Patients with somatostatin receptor subtype 2-positive metastasised neuroendocrine tumours can be treated with [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate. Some use octreotide as the peptide for peptide receptor radionuclide therapy (PRRT). We compared in seven patients [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotide ({sup 177}Lu-DOTATOC) and [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate ({sup 177}Lu-DOTATATE), to see which peptide should be preferred for PRRT with {sup 177}Lu. In the same patients, 3,700 MBq {sup 177}Lu-DOTATOC and 3,700 MBq {sup 177}Lu-DOTATATE was administered in separate therapy sessions. Amino acids were co-administered. Whole-body scanning was performed on days 1, 4 and 7 post therapy. Blood and urine samples were collected. We calculated residence times for tumours, spleen and kidneys. All patients had longer residence times in spleen, kidneys and tumours after use of {sup 177}Lu-DOTATATE (p=0.016 in each case). Comparing {sup 177}Lu-DOTATATE with {sup 177}Lu-DOTATOC, the mean residence time ratio was 2.1 for tumour, 1.5 for spleen and 1.4 for kidneys. Dose-limiting factors for PRRT are bone marrow and/or kidney dose. Although the residence time for kidneys was longer when using {sup 177}Lu-DOTATATE, the mean administered dose to tumours would still be advantageous by a factor of 1.5, assuming a fixed maximum kidney dose is reached. Plasma radioactivity after {sup 177}Lu-DOTATATE was comparable to that after {sup 177}Lu-DOTATOC. Urinary excretion of radioactivity was comparable during the first 6 h; thereafter there was a significant advantage for {sup 177}Lu-DOTATOC. {sup 177}Lu-DOTATATE had a longer tumour residence time than {sup 177}Lu-DOTATOC. Despite a longer residence time in kidneys after {sup 177}Lu-DOTATATE, tumour dose will always be higher. Therefore, we conclude that the better peptide for PRRT is octreotate. (orig.)

  4. Photoionization spectroscopy for laser extraction of the radioactive isotope 177Lu

    D'yachkov, A. B.; Firsov, V. A.; Gorkunov, A. A.; Labozin, A. V.; Mironov, S. M.; Panchenko, V. Y.; Semenov, A. N.; Shatalova, G. G.; Tsvetkov, G. O.

    2015-12-01

    The hyperfine structure of the 5 d6 s 2 2D3/2 → 5 d6 s6 p 4F5/2 transition of the radioactive isotope 177Lu has been investigated by laser photoionization spectroscopy. Measured spectra permitted the determination of hyperfine magnetic dipole constants and electric quadrupole constants for ground and excited state as well as the isotope shift of the 177Lu isotope. The data obtained were used to confirm the selective photoionization of 177Lu from a neutron-irradiated sample that initially had a natural isotope composition. A concentration for 177Lu of 50 % was achieved, and the photoionization efficiency was estimated as suitable for technological application.

  5. 177Lu radiochemical separation from 176Yb irradiated in high-flux research reactor SM

    Ytterbium and lutetium behaviour has been studied during electrolysis of aqueous solutions containing their chlorides and alkali metal citrate (Li, Na, K). The conditions providing the efficient extraction of ytterbium macro amounts into a mercury-pool cathode have been determined. Laboratory-scale experiments were performed to elaborate chromatographic procedures for 177Lu purification from ytterbium macro amounts and accompanying impurities including hafnium (177Lu radioactive decay product). The conditions providing the efficient separation of 177Lu from the above-mentioned impurities using cation-exchange (in α-hydroxy isobutyric acid) and extraction-chromatographic (impregnated with di-2-ethylhexyl phosphoric acid teflon powder as stationary phase and nitric or hydrochloric acids as eluant) methods have been found. Isotopically enriched ytterbium preparation (176Yb - 95.15; 174Yb - 2.47 atomic %) was purified from lutetium impurity and samples of the purified starting material were irradiated in the central neutron trap and beryllium reflector channel of the SM reactor. 177Lu was extracted from the irradiated targets by electroreduction of ytterbium on the mercury-pool cathode from lithium citrate solution. Cation exchange and extraction chromatography methods were used for subsequent purification of 177Lu. The radiochemical processing took about 50 hours. The results of analysis obtained by the spectrometry of X-ray and gamma radiation, mass-spectrometry and emission spectroscopy are as follows: Chemical form: 177LuCl3, solution in hydrochloric acid; solvent (HCl) concentration: 0.01 - 0.1 mol/l; 177Lu specific activity: ≥ 20 Ci/mg; 177mLu to 177Lu activity ratio: ≤ 0.02 %; total gamma emitters (Co-58, Co-60, Zn-65, Mn-54, Fe-59, Cr-51) to 177Lu activity ratio: ≤ 0.01 %; total mass of non-radioactive impurities (Cu, Zn, Al, Fe, Pb) to 177Lu activity ratio: ≤ 500 μg/Ci; total alpha emitters to 177Lu activity ratio ≤ 1x10-5 %. (author)

  6. On the preparation of a therapeutic dose of 177Lu-labeled DOTA-TATE using indigenously produced 177Lu in medium flux reactor

    177Lu could be produced with a specific activity of ∼23,000 mCi/mg (850 GBq/mg) by neutron activation using enriched 176Lu (64.3%) target when irradiation was carried out at a thermal neutron flux of 1x1014 n/cm2/s for 21 d. 177Lu-DOTA-TATE could be prepared in high radiochemical yield (∼99%) and adequate stability using the 177Lu produced indigenously. The average level of radionuclidic impurity burden in 177Lu due to 177mLu was found to be 250 nCi of 177mLu/1 mCi of 177Lu (9.25 kBq/37 MBq) at the end of bombardment, which corresponds to 0.025% of the total activity produced. The maximum specific activity achievable via careful optimization of the irradiation parameters was found to be adequate for the preparation of a therapeutic dose of the radiopharmaceutical. The in-house preparation of this agent using 25 μg (17.41 nmole) of DOTA-TATE and indigenously produced 177Lu (0.8 μg, 4.52 nmole), corresponding to peptide/Lu ratio of 3.85 yielded 98.7% complexation. Allowing possibility of decay due to transportation to users, it has been possible to demonstrate that at our end, a single patient dose of 150-200 mCi (5.55-7.40 GBq) can be prepared by using 250-333 μg of DOTA-TATE conjugate. This amount compares well with 177Lu-DOTA-TATE prepared for a typical peptide receptor radionuclide therapy (PRRT) procedure which makes use of 100 μg of the DOTA-TATE conjugate, which incorporates 50 mCi (1.85 GBq) of 177Lu activity, thereby implying that in order to achieve a single patient dose of 150-200 mCi (5.55-7.40 GBq), 300-400 μg of the conjugate needs to be used

  7. Occupational doses in neuroendocrine tumors by using 177Lu DOTATATE

    This paper investigated the treatment of neuroendocrine tumors (abdominal tumors) using of 177Lu DOTATATE radiopharmaceutical which is a type of treatment presently used in the experimental form in Brazil and, therefore, not contemplated in norms or specific use. This research studied the occupational doses of this treatment and suggested guidelines or rules of procedures viewing the radiological protection of workers involved and the public. The treatment were followed up by using two types of radiation detection, one a scintillator and a Geiger-Muller, and the measurements were performed in a public hospital at Rio de Janeiro and the other in a private hospital at Sao Paulo. It was observed that the equivalent occupational doses can variate from 160 μSv to 450 μSv, in function of operator, of stage of manipulation, and of the administration method, which can be through the use of infusion pump or manual injection. The use of infusion pump is highly recommended and the hospitalization of the patient until the dose rate measured at 1 m does not surpass 20 μSv/h

  8. Development of 177Lu-phytate Complex for Radiosynovectomy

    Hassan Yousefnia

    2013-05-01

    Full Text Available Objective(s: In this work a new possible agent for radiosynovectomy has been targeted for articular pain palliation. Materials and Methods: Lu-177 of 2.6-3 GBq/mg specific activity was obtained by irradiation of natural Lu2O3 sample with thermal neutron flux of 4 × 1013 n.cm-2.s-1. The product was converted into chloride form which was further used for labeling of 177Lu-phytate complex and checked using ITLC (MeOH: H2O: acetic acid, 4: 4: 2, as mobile phase. The complex stability and viscosity were checked in the final solution up to seven days. The prepared complex solution (100 µCi/100 µl was injected intra-articularly to male rat knee joint. Leakage of radioactivity from injection site and its distribution in organs were investigated up to seven days. Results: The complex was successfully prepared with high radiochemical purity (>99.9 %. Approximately, the whole injected dose has remained in injection site seven days after injection. Conclusion: The complex was proved to be a feasible agent for cavital radiotherapy in oncology and rheumatology

  9. DOTA-Tyr3-octreotate labelled with 177Lu and 131I. A comparative evaluation

    The chemical structure of somatostatin receptor ligand 1,4,7,10-tetraazacyclododecane- N,N',N',N'''-tetraacetic acid-Tyr3-octreotate (DOTA-Tyr3-TATE), provides the means for radiolabelling with halogen, by electrophilic substitution, to the Tyr3 residue and with metal, by a coordination mechanism, to the DOTA chelator. In this study, the DOTA-Tyr3-TATE was radiolabelled with 177Lu and 131I of high radiochemical purity and specific activity. The in vitro study regarding the competitive and the saturation binding assays were performed using rat brain cortex membrane. The IC50 value was determined as 4.74nM for natLu-DOTA-Tyr3-TATE and the Kd value was 142.8pM for 177Lu-DOTA-Tyr3-TATE. The biodistribution data of 177Lu-DOTA-Tyr3-TATE and DOTA-131I-Tyr3-TATE in HRS1 (hepato-colangiom carcinomas) tumour bearing rats, show that the 177Lu-DOTA-Tyr3-TATE is more stable and has better uptake than DOTA-131I-Tyr3-TATE. Furthermore, the competitive localization index of 177Lu- DOTA-Tyr3-TATE is three times higher than that obtained for DOTA-131I -Tyr3-TATE. The results of work based on comparative experiments suggest that 177Lu-DOTA-Tyr3- TATE could be an effective targeted radiotherapy agent of SSTR tumours. (author)

  10. 188W/188Re Generator System and Its Therapeutic Applications

    A. Boschi

    2014-01-01

    Full Text Available The 188Re radioisotope represents a useful radioisotope for the preparation of radiopharmaceuticals for therapeutic applications, particularly because of its favorable nuclear properties. The nuclide decay pattern is through the emission of a principle beta particle having 2.12 MeV maximum energy, which is enough to penetrate and destroy abnormal tissues, and principle gamma rays (Eγ=155 keV, which can efficiently be used for imaging and calculations of radiation dose. 188Re may be conveniently produced by 188W/188Re generator systems. The challenges related to the double neutron capture reaction route to provide only modest yield of the parent 188W radionuclide indeed have been one of the major issues about the use of 188Re in nuclear medicine. Since the specific activity of 188W used in the generator is relatively low (<185 GBq/g, the eluted Re188O4- can have a low radioactive concentration, often ineffective for radiopharmaceutical preparation. However, several efficient postelution concentration techniques have been developed, which yield clinically useful Re188O4- solutions. This review summarizes the technologies developed for the preparation of 188W/188Re generators, postelution concentration of the 188Re perrhenate eluate, and a brief discussion of new chemical strategies available for the very high yield preparation of 188Re radiopharmaceuticals.

  11. Labelling of Biotin with 188Re. Chapter 8

    Different chemical strategies have been employed for labelling biotin using 188Re with the aim to develop a sterile and pyrogen free kit formulation that is suitable for clinical use. A number of biotin conjugated 188Re complexes were prepared and evaluated to determine their affinity for avidin. The most difficult challenge was to devise an efficient reaction pathway that was able to obtain the final radiocompounds in a high radiochemical yield. This work describes the molecular design and the chemical strategy that were followed to obtain reliable preparation of the new radiopharmaceuticals starting from generator produced [188ReO4]–. (author)

  12. Uncertainties in measurement of 90Y and 177Lu activities in an ionisation chamber

    Full text of publication follows. Accurate measurement of administered activity is essential in radionuclide therapy. However, this can be difficult to perform using a standard ionisation chamber, particularly with beta emitting radionuclides where measurements are greatly affected by the type of container (e.g. glass vial vs plastic syringe) in which the activity is contained, as well as the shape and volume of the sample. Methods: All measurements were taken with one of two ionisation chambers of the same model (Capintec CRC-15R). Shipments were received from two different suppliers of 90Y (Polatom; Eckert-Ziegler-EZ) and two suppliers of 177Lu (ITG Munich; Advanced Accelerator Applications-AAA). The quantities of 90Y varied from 2.5-7.4 GBq and of 177Lu from 3.3-8.4 GBq. The calibration factors used to make measurements in the glass vials supplied were 62*10 for 90Y and 450*10 for 177Lu. A reference sample of 177Lu was sent to the UK National Physical Laboratory, Teddington, for absolute calibration. Results: Compared to the manufacturer's calibration, the activities received were (88±23%) for Polatom 90Y (n=7), (103±5%) for EZ 90Y (n=56), (94±2%) for ITG 177Lu (n=93) and (112±5%) for AAA 177Lu (n=14). The large variation in measurements on Polatom 90Y was due to one shipment at 36%; without that value the mean was (96±4%) (n=6). With AAA 177Lu there was a step change during the process with the initial shipments reading significantly higher than the later ones: (115±1%) (n=10) vs (105±4%) (n=4). With 90Y a different calibration factor was required for doses drawn into syringes (49*10), whereas with 177Lu the same value could be used; this is presumably due to the contribution of the gamma emissions of 177Lu. Cross calibration with the national metrology institute showed that our measurements were within about 1% of the accepted value for 177Lu. Conclusions: Accurate measurement of beta emitters used in radionuclide therapy requires careful attention

  13. Radiolabeling parameters of {sup 177}Lu-DOTA-RITUXIMAB

    Massicano, Adriana V.F.; Alcarde, Lais F.; Oliveira, Ricardo S.; Mengatti, Jair; Araujo, Elaine B. de, E-mail: adriana.avfernandes@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Cancer treatment using radioimmunotherapy (RIT) has been the focus of much research in the last two decades. In RIT, a radioisotope is coupled to a monoclonal antibody (mAb) to form a tumor-specific target agent to improve the cytocidal effect of the mAbs. RIT allows the systemic delivery of radiation to disease target by mAbs while sparing normal tissues. Rituximab® (Mabthera - Roche) is a chimeric mouse-human monoclonal antibody; it selectively binds with high affinity to the CD20 antigen, a hydrophobic transmembrane protein, which is expressed on B-lymphocytes and in more than 90% of B cell non-Hodgkin's lymphomas (NHL). The conjugation and radiolabeling process involve special conditions of pH and temperature, long processes of manipulation and mixing. All this process can damage the antibody structure and compromise its clinical application. Therefore, these parameters must be largely studied. The aim of this work was to evaluate the best radiolabeling conditions of DOTA-rituximab. Briefly, 10 mg of antibody previously purified by ultrafiltration device was conjugated with DOTA-NHS-ester (Macrocyclics) in 50 fold molar excess. The reaction was conducted for 1 hour in phosphate buffer pH 8.0 and gently mixing at room temperature, remaining for 24 hours under refrigeration. The immunoconjugated was purified by size exclusion column and ultrafiltration device. The radiolabeled parameters studied were: immunoconjugated mass, activity of {sup 177}LuCl{sub 3}, reaction time, temperature and pH. The radiochemical purity of the preparations was determined using analysis by thin layer chromatography (TLC-SG plates). The best studied condition presented radiochemical purity above 95% and the integrity of antibody was preserved. (author)

  14. Aspects of yield and specific activity of (n,γ) produced 177Lu used in targeted radionuclide therapy

    177Lu-labeled receptor avid peptides and monoclonal antibodies have been effectively used in targeted tumor therapy, owing to the ideally suited decay properties and favourable production logistics of 177Lu [T½ = 6.65 days; Eβ(max) = 497 keV (78.6 %); Eγ = 208 keV (11.0 %)]. The specific activity of 177Lu produced by the (n,γ) route is one of the important criteria, which determines the efficacy of 177Lu-labeled receptor-avid biomolecules. The present article highlights that the specific activity of (n,γ) produced 177Lu cannot be calculated by simply dividing the produced activity by the mass of the target irradiated, unlike other (n,γ) produced medical radioisotopes and there is a significant enhancement of specific activity due to the burn up of the Lu target during irradiation, which is an added advantage towards the utilization of 177Lu in receptor specific therapeutic radiopharmaceuticals. (author)

  15. Extraction centrifugal W-188/Re-188 generator for radiotherapeutic applications

    188 Re extraction generator for medical purposes development results are presented. The main advantage of such generator is the possibility to use as starting material the tungsten oxide of natural isotope composition irradiated in react or with mean neutron flux (1.0– 1.4·10 14 n ⋅ cm-2 ⋅ s-1). The parent (188 W) and daughter radionuclides were separated using centrifugal semicounter -current extractor developed at Physical Chemistry and Electrochemistry Institute under RAS (Russian Academy of Sciences). In the course of simulated solution experiments, optimal operating conditions were established for 188 Re production process. For this purpose, it is proposed to recover 188 Re by methylethylketone from alkaline solution (2.5 M KON + 2.5 M K2CO3) containing up to 200 g/l of W element. Methylethylketone is subsequently evaporated to dryness and residue is dissolved in isotonic solution of NaCl. An extraction generator model was built in hot cell; the process developed was then tested on radioactive solutions. The test has shown that the yield is 89% in the average and the radiochemical purity of 188 Re solution is ~ 97%. The activity of 188 W was less than 1·10-3 relative to that of 188 Re. Activity of other radioisotopes was below 1·10-4 . The content of inorganic impurities in 188 Re solution is determined only by the purity of aqueous solutions used for 188 Re dissolution. The generator model may be recommended as a basis for creation of commercial prototype of 188 Re extraction generator. Key words: extraction, generator, methylethylketone, radiopharmaceutical, metastases, preclinical research

  16. Preparation of 177Lu-DOTA/DTPA-Bz-Cys-RGD dimer and biodistribution evaluation in normal mice

    177Lu-DOTA-Bz-Cys-RGD dimer and 177Lu-DTPA-Bz-Cys-RGD dimer were prepared, and the in vitro and in vivo properties were compared. TLC and HPLC show that the labeling yields of two radiolabeled compounds are more than 95% under optimal conditions (pH=5.0, reacting at 100 degree C for 15-20 min), and the two radiolabeled compounds show pretty good in vitro stability. HPLC analyses and lg P values reveal that lipophilicity of 177Lu-DOTA-Bz-Cys- RGD dimer is higher than 177Lu-DTPA-Bz-Cys-RGD dimer. The uptake of 177Lu-DTPA-Bz-Cys- RGD dimer in other tissues is significantly higher than that of 177Lu-DOTA-Bz-Cys-RGD dimer at 4 h postinjection, except for blood and spleen. The in vivo stability of 177Lu-DOTA-Bz-Cys-RGD dimer is much better than 177Lu-DTPA-Bz-Cys-RGD dimer. Bz-DOTA is an ideal bifunctional chelator for 177Lu labeling of RGD dimer. (authors)

  17. Preparation, QC and biological evaluation of 177Lu-DOTA-Tyr3- Octreotate

    Somatostatin (SS) plays a major role in the physiological regulation of hormones and organs. Radiolabelled somatostatin analogues have been studied for targeted radiotherapy of neuroendocrine tumors and with other malignancies known to bear somatostatin receptor, such as lymphoma, breast cancer, small-cell lung cancer and melanoma. Reactor produced 177Lu is emerging as an important radionuclide for cancer therapy since it decays with half-life of 6.71d by the emission of β- particles with Eβ of 498 keV (78.6), 384 keV (9.1%) and 176 keV (12.2) to stable 177Hf. The 177Lu radionuclide has tissue mean range of 670 μm is considered to be more effective for the treatment of small tumour. High specific activity 177Lu radionuclide (> 8Ci/mg) prepared in our laboratory is considered to be appropriate for labelling peptides. Several experiments for obtaining optimum labelling yield of 177Lu-DOTA-Tyr3-Octreotate under different reaction parameters such pH, incubation time and reaction temperature were performed. Radiochemical purity of 177Lu-DOTA-Tyr3- Octreotate was determined by radio-TLC with C18 plates developed in 70:30 MeOH:10% NH4OAc. Under these conditions 177Lu-DOTA-Tyr3-Octreotate appears at Rf 0.8 while 177Lu-acetate stays at the Rf 0. High labelling yield (>98%) of 177Lu-DOTA-Tyr3-Octreotate was obtained at pH 4.5 at a temperature of 90 deg. C for 30 minutes incubation time. The 177Lu-DOTA-Tyr3-Octreotate was further investigated for stability in acetate/ascorbate buffer and saline at room temperature (12.15 deg. C). The data showed that the labelled complex was stable in buffer and saline medium for a period >24 hours. Animal study of 177Lu-DOTA-Tyr3-Octreotate was performed in ∼200 g male Sprague Dawley rats. Two hundred microlitres of the labelled (80 μCi) were injected into the tail veins of rats and each rat was killed at 1 hour, 2 hours, 6 hours, 12 hours, 24 hours and 72 hours. Countings were performed using Capintec dose calibrator. The

  18. Investigation of 177Lu-folate based radionuclide tumor therapy in combination with pemetrexed

    Full text of publication follows. Aim: The antifolate pemetrexed (PMX) was shown to improve the tissue distribution profile of radio-folates by reducing undesired renal accumulation without affecting uptake in the tumor. We hypothesized that PMX would have a dual role in combination with therapeutic radio-folates as it may protect kidneys from radio-nephrotoxicity and contribute to the anticancer effect as a chemotherapeutic and/or radiosensitizing agent. Therefore, the aim of the study was to investigate the combined application of 177Lu-folate and PMX in vitro an in vivo. Material and Methods: The DOTA-folate conjugate (EC0800, Endocyte Inc.) was labeled with 177Lu at high specific activity. In vitro the effects of 177Lu-EC0800 alone and in combination with PMX was tested with FR-positive KB tumor cells using MTT and clonogenic assays. In vivo, undesired effects of 177Lu-EC0800 (20 MBq/mouse) with/without co-application of PMX were investigated in non-tumor bearing mice over six months. Kidney function was monitored by the determination of renal accumulation of 99mTc-DMSA using SPECT. Therapy studies in KB tumor-bearing mice were performed with 177Lu-EC0800 (20 MBq) combined with subtherapeutic (0.4 mg) and therapeutic amounts (1.6 mg) of PMX. Results: Determination of the combination index revealed a synergistic inhibitory effect of 177Lu-EC0800 and PMX on the viability of both FR-positive cancer cell lines in vitro (CI < 0.8). In vivo application of 20 MBq 177Lu-EC0800 impaired kidney function 6 months as demonstrated by a significantly reduced renal uptake of 99mTc-DMSA and elevated plasma levels of blood urea nitrogen. Pre-injection of subtherapeutic amounts of PMX (0.4 mg) protected kidneys effectively as demonstrated by parameters which were in the same range as those of untreated control animals. Therapy studies revealed a 3-fold more pronounced anticancer effect and 25% increased survival if 177Lu-EC0800 was combined with therapeutic amounts of PMX

  19. Improving quantitative dosimetry in (177)Lu-DOTATATE SPECT by energy window-based scatter corrections

    de Nijs, Robin; Lagerburg, Vera; Klausen, Thomas L;

    2014-01-01

    PURPOSE: Patient-specific dosimetry of lutetium-177 ((177)Lu)-DOTATATE treatment in neuroendocrine tumours is important, because uptake differs across patients. Single photon emission computer tomography (SPECT)-based dosimetry requires a conversion factor between the obtained counts and the...... activity, which depends on the collimator type, the utilized energy windows and the applied scatter correction techniques. In this study, energy window subtraction-based scatter correction methods are compared experimentally and quantitatively. MATERIALS AND METHODS: (177)Lu SPECT images of a phantom with...... technique, the measured ratio was close to the real ratio, and the differences between spheres were small. CONCLUSION: For quantitative (177)Lu imaging MEGP collimators are advised. Both energy peaks can be utilized when the ESSE correction technique is applied. The difference between the calculated and the...

  20. Production Ability Of 177Lu From Natural Lutetium Target On The Dalat Nuclear Reactor

    177Lu is presently being considered as a potential radionuclide, for use in in-vivo targeted radiotherapy, owing to its favorable nuclear decay characteristics. This paper presents some research findings on the ability to produce 177Lu on the IVV-9 research reactor with thermal neutron flux of 1.8 x 1013.cm-2.s-1 at the Nuclear Research Institute to produce this radioactive isotope. Our products have specific activity of 17.7 mCi/mg Lu, radionuclide and radiochemical purities more than 99.9% of total radioactivity. Immediate products are used for the initial basic research of labeling capabilities with DOTATATE, and especially studying on the possibility preparing 177Lu-EDTMP used to treat pain palliation caused by bone metastases. (author)

  1. The addition of DTPA to [177Lu-DOTA0,Tyr3]octreotate prior to administration reduces rat skeleton uptake of radioactivity

    Peptide receptor-targeted radionuclide therapy is nowadays also being performed with DOTA-conjugated peptides, such as [DOTA0,Tyr3]octreotate, labelled with radionuclides like 177Lu. The incorporation of 177Lu is typically ≥99.5%; however, since a total patient dose can be as high as 800 mCi, the amount of free 177Lu3+ (= non-DOTA-incorporated) can be substantial. Free 177Lu3+ accumulates in bone with unwanted irradiation of bone marrow as a consequence. 177Lu-DTPA is reported to be stable in serum in vitro, and in vivo it has rapid renal excretion. Transforming free Lu3+ to Lu-DTPA might reroute this fraction from accumulation in bone to renal clearance. We therefore investigated: (a) the biodistribution in rats of 177LuCl3, [177Lu-DOTA0,Tyr3]octreotate and 177Lu-DTPA; (b) the possibilities of complexing the free 177Lu3+ in [177Lu-DOTA0,Tyr3]octreotate to 177Lu-DTPA prior to intravenous injection; and (c) the effects of free 177Lu3+ in [177Lu-DOTA0,Tyr3]octreotate, in the presence and absence of DTPA, on the biodistribution in rats. 177LuCl3 had high skeletal uptake (i.e. 5% ID per gram femur, with localization mainly in the epiphyseal plates) and a 24-h total body retention of 80% injected dose (ID). [177Lu-DOTA0,Tyr3]octreotate had high and specific uptake in somatostatin receptor-positive tissues, and 24-h total body retention of 19% ID. 177Lu-DTPA had rapid renal clearance, and 24-h total body retention of 4% ID. Free 177Lu3+ in [177Lu-DOTA0,Tyr3]octreotate could be complexed to 177Lu-DTPA. Accumulation of 177Lu in femur, blood, liver and spleen showed a dose relation to the amount of free 177Lu3+, while these accumulations could be normalized by the addition of DTPA. After labelling [DOTA0,Tyr3]octreotate with 177Lu the addition of DTPA prior to intravenous administration of [177Lu-DOTA0,Tyr3]octreotate is strongly recommended. (orig.)

  2. Preparation and evaluation of 177Lu-DOTA-Bz-RGD dimer and 177Lu-DOTA-Bz-PEG4-RGD dimer

    177Lu-DOTA-Bz-RGD dimer and 177Lu-DOTA-Bz-PEG4-RGD dimer were pre- pared, and the effect of PEG4 on labeling conditions and in vitro stability as well as pharma-cokinetic properties and biodistribution in normal mice for the radiolebeled compounds was compared. The results of TLC and HPLC show that the labeling yield of two radiolabeled compounds was more than 95% under optimal conditions (pH 4.0 and pH 6.0, respectively, reacting at 100 degree C for 15-20 min). The two radiolabeled compounds show pretty good stability in saline. HPLC analyses and lgPow values revealed that introducing of PEG4 increased the lipophilic character of radiolabeled compounds, but had no significant changes on pharmacokinetic properties and biodistribution in normal mice. (authors)

  3. Development of a therapeutic radiopharmaceutical 177Lu-DOTA- Minigastrin for potential use in PRRT

    The aim of this work is to obtain 177Lu-DOTA-Minigastrin with high radiochemical purity (RP) and the highest specific activity (Ae) as possible, using a locally produced (Nuclear Reactor RA-3, Ezeiza Atomic Center) 177LuCl3 of an intermediate level of Ae (between 6.36 to 17.95 Ci/mg of 176Lu) ) and also to perform in vitro and in vivo stability tests, dose calculation in normal mice and its extrapolation to a human model. (authors)

  4. Preparation and biological evaluation of 177Lu-labeled rituximab for B-lymphoma treatment

    Edalat Radfar; Azim Arbabi; Dariush Sardari

    2010-01-01

    Introduction: 177Lu is a beta emitter with suitable decay mode [T1/2=6.7 d, Eβmax=497 keV, EΥ=112keV (6.4%) & 208 keV (11%)] for using in radio therapy. Various radiolabeled monoclonal antibodies have been developed in treatment. Rituximab is a chimeric mouse-human monoclonal antibody. Rituximab binds with human B-lymphocate-restricted differentiation antigen: CD20. Rituxsimab was used successfully as an anti-CD20 radiolabeled antibody before. Methods: 177Lu was p...

  5. Antitenascin antibody 81C6 armed with 177Lu: in vivo comparison of macrocyclic and acyclic ligands

    Introduction: When labeled with iodine-131, the antitenascin monoclonal antibody (mAb) 81C6 has shown promise as a targeted radiotherapeutic in patients with brain tumors. Because of its more favorable γ-ray properties, lutetium-177 might be a better low-energy β-emitter for this type of therapy. Materials and Methods: Chimeric 81C6 (ch81C6) was labeled with 177Lu using the acyclic 1B4M ligand and the macrocyclic ligands NHS-DOTA and MeO-DOTA and evaluated for binding to tenascin. Three paired-label tissue distribution experiments were performed in normal mice receiving one of the 177Lu-labeled immunoconjugates plus 125I-labeled ch81C6 labeled using Iodogen. Paired-label experiments in athymic mice bearing subcutaneous D54 MG human glioma xenografts were done to directly compare the biodistribution of ch81C6-1B4M-177Lu and 125I-labeled ch81C6, and ch81C6-MeO-DOTA-177Lu and 125I-labeled ch81C6. Similar comparisons were done using murine (mu) instead of ch81C6. The primary parameter utilized for evaluation was the 177Lu/125I uptake ratio in each tissue. Results: In the studies performed in normal mice, the NHS-DOTA ligand yielded the highest 177Lu/125I uptake ratios in tissues indicative of loss of label from the chelate; for this reason, only 1B4M and MeO-DOTA were evaluated further. The 177Lu/125I ratio in bone increased gradually with time for the chimeric conjugates; however, there were no significant differences between ch81C6-1B4M-DTPA-177Lu and ch81C6-MeO-DOTA-177Lu. In contrast, mu81C6-1B4M-DTPA-177Lu and mu81C6-MeO-DOTA-177Lu showed a more dramatic increase in the 177Lu/125I ratio in bone - from 2.4±0.3 and 1.7±0.2 at Day 1 to 8.5±1.1 and 4.2±0.5 at Day 7, respectively. Conclusion: With these antitenascin constructs, the nature of the mAb had a profound influence on the relative degree of loss of 177Lu from these immunoconjugates. MeO-DOTA shows promise as a bifunctional chelate for labeling 81C6 mAbs with 177Lu

  6. Tracer level radiochemistry to clinical dose preparation of 177Lu-labeled cyclic RGD peptide dimer

    Aim: Integrin αvβ3 plays a significant role in angiogenesis during tumor growth and metastasis, and is a receptor for the extracellular matrix proteins with the exposed arginine(R)-glycine(G)-aspartic acid(D) tripeptide sequence. The over-expression of integrin αvβ3 during tumor growth and metastasis presents an interesting molecular target for both early detection and treatment of rapidly growing solid tumors. Considering the advantages of 177Lu for targeted radiotherapy and enhanced tumor targeting capability of cyclic RGD peptide dimer, an attempt has been made to optimize the protocol for the preparation of clinical dose of 177Lu labeled DOTA-E[c(RGDfK)]2 (E = Glutamic acid, f = phenyl alanine, K = lysine) as a potential agent for targeted tumor therapy. Methods: 177Lu was produced by thermal neutron bombardment on enriched Lu2O3 (82% in 176Lu) target at a flux of 1 × 1014 n/cm2.s for 21 d. Therapeutic dose of 177Lu-DOTA-E[c(RGDfK)]2 (7.4 GBq) was prepared by adding the aqueous solution of the ligand and 177LuCl3 to 0.1 M NH4OAC buffer containing gentisic acid and incubating the reaction mixture at 90 °C for 30 min. The yield and radiochemical purity of the complex was determined by HPLC technique. Parameters, such as, ligand-to-metal ratio, pH of the reaction mixture, incubation time and temperature were varied using tracer quantity of 177Lu (37 MBq) in order to arrive at the optimized protocol for the preparation of clinical dose. Biological behavior of the radiotracer prepared was studied in C57/BL6 mice bearing melanoma tumors. Results: 177Lu was produced with a specific activity of 950 ± 50 GBq/mg (25.7 ± 1.4 Ci/mg) and radionuclidic purity of 99.98%. A careful optimization of several parameters showed that 177Lu-DOTA-E[c(RGDfK)]2 could be prepared with adequately high radiochemical purity using a ligand-to-metal ratio ∼ 2. Based on these studies therapeutic dose of the agent with 7.4 GBq of 177Lu was formulated in ∼ 63 GBq/μM specific

  7. Development of a 188W/188Re Generator

    The fabrication of a 188W/188Re generator is described in detail, including the stability testing and quality control methods used. Studies of the elution profiles of four generators showed that about 90% of the available activity was contained in a 4 mL volume of saline solution with high radioactive concentration. The generators were usable for over 6 months, and the quality of the eluate was within the approved specifications. An illustration of a shielding container made of tungsten for a 188Re eluate vial is also included. (author)

  8. Production of carrier-free 188Re in the past ten years in Taiwan

    Twenty clinical scale alumina-based 188W/188Re generators and carrier-free 188Re has been produced at the Institute of Nuclear Energy Research (INER-Taiwan) for over ten years. 2845.6 GBq (76.9 Ci) of 188Re-perrhenate solution has been eluted from generators during the past ten years. We have used the harvesting 188Re solution for labeling radiopharmaceuticals, such as 188Re-HEDP, 188Re-MDP, 188Re-microsphere, 188Relipiodol, and 188Re-sulfur colloid, etc. The average eluting yield of 188Re is 78.6±5.8% that was investigated at 1115 harvesting times from 20 generators. Each generator can be used more than six months but the Millipore needs to be changed every two months for smooth harvesting and high yield of 188Re solution. (author)

  9. Preparation and preclinical evaluation of (177)Lu-nimotuzumab targeting epidermal growth factor receptor overexpressing tumors

    Beckford, Denis R.; Eigner, Sebastian; Eigner-Henke, Kateřina; Lebeda, Ondřej; Melichar, František; Beran, Miloš

    2012-01-01

    Roč. 39, č. 1 (2012), s. 3-13. ISSN 0969-8051 R&D Projects: GA MŠk 2B06165 Institutional research plan: CEZ:AV0Z10480505 Keywords : Radioimmunotherapy * Nimotuzumab * (177)Lu * Monoclonal antibody Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.517, year: 2012

  10. Potential renal toxicity bio-markers indicating radiation injury after 177Lu-octreotate treatment

    Full text of publication follows. The kidneys are one of the most exposed non-tumor tissues and regarded as one of the main dose-limiting organs in peptide receptor radionuclide therapy (PRRT). [177Lu-DOTA0, Tyr3]-octreotate (177Lu-octreotate) has shown promising results in the treatment of somatostatin receptor over-expressing neuroendocrine tumors, but optimization is still needed. The ability to give each patient as much 177Lu-octreotate as possible without inducing nephrotoxicity is necessary for an efficient treatment. However, due to large inter-individual differences in uptake and retention in the kidneys, there is a need for efficient methods that can indicate renal injury early. A possible way is to identify bio-markers for high risk of radiation nephrotoxicity. The aim of this study was to investigate the potential of using urinary retinol binding protein (RBP), and blood valinhydantoin (VH) as bio-markers of nephrotoxicity on adult mice after 177Lu-octreotate treatment. BALB/c nude mice (n=6/group) were i.v. injected with 60 MBq or 120 MBq of 177Lu-octreotate. The control group was mock treated with saline. Spot urine samples were collected before injection, and 14, 30, 60 and 90 days after injection. Analysis of RBP4 and creatinine was performed using Mouse RBP4 ELISA kit and Creatinine kit from R/D Systems, respectively. Erythrocytes were separated from whole blood samples collected 90 days after injection, and analysed for VH by LC-MS/MS. The ratio between VH and a volumetric standard was calculated. The RBP/creatinine level increased with time in both groups given 177Lu-octreotate, with earlier and higher response for the 120 MBq group. No clear change in VH level between the different groups was observed. The results show that RBP may be a promising new bio-marker for radiation induced kidney toxicity. The presently used method based on VH was not sensitive enough to be used as kidney toxicity marker. Further studies on mice are ongoing to validate

  11. Reducing renal uptake of 9Y- and 177Lu-labeled alpha-melanocyte stimulating hormone peptide analogues

    Objective: The purpose of this study was to improve the tumor-to-kidney uptake ratios of 9Y- and 177Lu-[1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-Re-Cys3,4,1, D-Phe7, Arg11]α-melanocyte stimulating hormone3-13 {DOTA-Re(Arg11)CCMSH} through coupling a negatively charged glutamic acid (Glu) to the peptide sequence. Methods: A new peptide of DOTA-Re(Glu2, Arg11)CCMSH was designed, synthesized and labeled with 9Y and 177Lu. Pharmacokinetics of 9Y- and 177Lu-DOTA-Re(Glu2, Arg11)CCMSH was determined in B16/F1 murine melanoma-bearing C57 mice. Results: 9Y- and 177Lu-DOTA-Re(Glu2, Arg11)CCMSH exhibited significantly (P9Y- and 177Lu-DOTA-Re(Arg11)CCMSH at 30 min and at 2, 4 and 24 h after dose administration. The renal uptake values of 9Y- and 177Lu-DOTA-Re(Glu2, Arg11)CCMSH were 28.16% and 28.81% of those of 9Y- and 177Lu-DOTA-Re(Arg11)CCMSH, respectively, at 4 h postinjection. 9Y- and 177Lu-DOTA-Re(Glu2, Arg11)CCMSH displayed higher tumor-to-kidney uptake ratios than 9Y- and 177Lu-DOTA-Re(Arg11)CCMSH at 30 min and at 2, 4 and 24 h after dose administration. The tumor-to-kidney uptake ratio of 9Y- and 177Lu-DOTA-Re(Glu2, Arg11)CCMSH was 2.28 and 1.69 times of 9Y- and 177Lu-DOTA-Re(Arg11)CCMSH, respectively, at 4 h postinjection. The 9Y- and 177Lu-DOTA-Re(Glu2, Arg11)CCMSH activity accumulation was low in normal organs except for kidney. Conclusions: Coupling a negatively charged amino acid (Glu) to the CCMSH peptide sequence dramatically reduced the renal uptake values and increased the tumor-to-kidney uptake ratios of 9Y- and 177Lu-DOTA-Re(Glu2, Arg11)CCMSH, facilitating their potential applications as radiopharmaceuticals for targeted radionuclide therapy of melanoma

  12. Preparation and preclinical evaluation of 177Lu-nimotuzumab targeting epidermal growth factor receptor overexpressing tumors

    Objectives: Nimotuzumab (h-R3) is a humanized monoclonal antibody (mAb) which recognizes the external domain of the epidermal growth factor receptor (EGFR) with high specificity. It was demonstrated that h-R3 has a unique clinical profile for immunotherapy of adult gliomas and pediatric pontine gliomas. The aim of this work was to evaluate the conjugate 177Lu-h-R3 as a potential radioimmunoconjugate for radioimmunotherapy (RIT) of tumors overexpressing EGFR. Methods: h-R3 was modified with the macrocylcic ligand S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane tetraacetic acid (p-SCN-Bn-DOTA) and the acyclic ligand S-2-(4-Isothiocyanatobenzyl)-diethylenetriamine pentaacetic acid (p-SCN-Bn-DTPA); the immunoconjugates were labeled with no-carried added 177Lu. Specificity and affinity were tested using radioimmunoassays in a cell line overexpressing EGFR. Biodistribution in mice, healthy or bearing A431 epithelial carcinoma xenografts, was performed for 11 days. Tumor uptake, the influence of the nature of the chelate and the way of administration were studied. Absorbed dose in tumor and selected organs was calculated using the OLINDA/EXM software; the data from the animals was extrapolated to humans. Results: 177Lu-h-R3 conjugates were obtained with specific activity up to 915 MBq/mg without significant loss of immunoreactivity. The binding of 177Lu-h-R3 conjugates to A431 cells showed to be EGFR specific, and the affinity was similar to native h-R3. Tumor uptake reached a maximum value of 22.4±3.1 %ID/g at 72 h and remained ∼20% ID/g over 1 week. Locoregional application showed better tumor/nontumor ratios than intravenous application. Conclusions: 177Lu-h-R3 should be considered for further evaluations as a potential radiopharmaceutical for RIT of tumors overexpressing EGFR.

  13. Labeling of MDP with 188Re for bone tumour therapy

    188Re is one of the most attractive radioisotopes for a variety of therapeutic applications in nuclear medicine, due to its physical decay properties, such as β- emission of 2.12 MeV, γ emission of 155 keV and half life of 16.9 hours. Biphosphonates are potent inhibitors of osteoclastic bone resorption and are effective in several diseases that cause bone fragility and bone metastases. Because of these characteristics, labeled biphosphonates have been studied for bone pathologies, also acting as palliation of bone pain in case of metastasis.The aim of this study was to optimize the labeling of a phosphonate-MDP (Sodium Methylene Diphosphonate) with 188Re for use in bone pain palliation. 188Re was obtained by eluting a 188W-188Re generator from POLATOM. The labeling was performed at room temperature using MDP, SnCl2 as reducing agent and ascorbic acid. The variables studied were: Mass of ligand (3, 6 and 10 mg), reducing agent mass (5, 7, 10 and 11 mg), ascorbic acid mass (1, 3, 5 and 6 mg), pH (1 and 2) and time of reaction (15, 60, 120, 360 and 4320 minutes), that also reflected the stability of the radiopharmaceutical. The radiochemical control, that also measures the labeling efficiency was evaluated by paper chromatography using Whatman 3MM paper and the solvents acetone and 0.9%NaCl. The best formulation was the following: Mass of ligand MDP: 10 mg, mass of SnCl2: 5 mg, ascorbic acid mass: 3 mg, time of reaction: 30 minutes, pH: 1. Under optimum conditions, 188Re MDP radiolabeling yield was 98,07% and the radiopharmaceutical was stable up to 72 h. (author)

  14. Hormonal crises following receptor radionuclide therapy with the radiolabeled somatostatin analogue [177Lu-DOTA0,Tyr3]octreotate

    Receptor radionuclide therapy is a promising treatment modality for patients with neuroendocrine tumors for whom alternative treatments are limited. The aim of this study was to investigate the incidence of hormonal crises after therapy with the radiolabeled somatostatin analogue [177Lu-DOTA0,Tyr3]octreotate (177Lu-octreotate). All 177Lu-octreotate treatments between January 2000 and January 2007 were investigated. Four hundred seventy-six patients with gastroenteropancreatic neuroendocrine tumors and three patients with metastatic pheochromocytoma were included for analysis. Four hundred seventy-nine patients received a total of 1,693 administrations of 177Lu-octreotate. Six of 479 patients (1%) developed severe symptoms because of massive release of bioactive substances after the first cycle of 177Lu-octreotate. One patient had a metastatic hormone-producing small intestinal carcinoid; two patients had metastatic, hormone-producing bronchial carcinoids; two patients had vasoactive intestinal polypeptide-producing pancreatic endocrine tumors (VIPomas); and one patient had a metastatic pheochromocytoma. With adequate treatment, all patients eventually recovered. Hormonal crises after 177Lu-octreotate therapy occur in 1% of patients. Generally, 177Lu-octreotate therapy is well tolerated. (orig.)

  15. A kit for preparation of 188Re sulfide suspension

    The 188Re sulfide suspension could be prepared quickly by a kit. The kit consists of three 10 mL vials. All the procedures were carried out in sterility circumstance. Vial A consisted of 1 mL KReO4 and Na2S2O3 (mole ratio 1:70) solution with excipient. Vial B was 5 mol/L HCl solution. Vial C consisted of 1.5 mL PVP and NaOH solution (mole ratio 1000:1). Vial B was sealed, Vial A and C were freeze-dried. Bacterium check, endotoxin check and security check were qualified. Kits were kept at ambient temperature and the Labelling efficiency of 188Re sulfide suspension was more than 98% with 2 months. The particle sizes were 1-5 μm (60.1 +- 12.7)%; 5-10 μm (30.9 +- 8.1)%; > 10 μm (9.0 +- 4.7)%. The radiochemical purity of 188Re sulfide suspension made by the kit was higher than 98% in 5 days with particle sizes 1-5 μm (49.9 +- 14.4%); 5-10 μm (41.1 +- 5.4)%; > 10μm (9.0 +- 3.3)%

  16. Stability and Biodistribution of Thiol-Functionalized and (177)Lu-Labeled Metal Chelating Polymers Bound to Gold Nanoparticles.

    Yook, Simmyung; Lu, Yijie; Jeong, Jenny Jooyoung; Cai, Zhongli; Tong, Lemuel; Alwarda, Ramina; Pignol, Jean-Philippe; Winnik, Mitchell A; Reilly, Raymond M

    2016-04-11

    We are studying a novel radiation nanomedicine approach to treatment of breast cancer using 30 nm gold nanoparticles (AuNP) modified with polyethylene glycol (PEG) metal-chelating polymers (MCP) that incorporate 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelators for complexing the β-particle emitter, (177)Lu. Our objective was to compare the stability of AuNP conjugated to MCP via a single thiol [DOTA-PEG-ortho-pyridyl disulfide (OPSS)], a dithiol [DOTA-PEG-lipoic acid (LA)] or multithiol end-group [PEG-pGlu(DOTA)8-LA4] and determine the elimination and biodistribution of these (177)Lu-labeled MCP-AuNP in mice. Stability to aggregation in the presence of thiol-containing dithiothreitol (DTT), l-cysteine or glutathione was assessed and dissociation of (177)Lu-MCP from AuNP in human plasma measured. Elimination of radioactivity from the body of athymic mice and excretion into the urine and feces was measured up to 168 h post-intravenous (i.v.) injection of (177)Lu-MCP-AuNP and normal tissue uptake was determined. ICP-AES was used to quantify Au in the liver and spleen and these were compared to (177)Lu. Our results showed that PEG-pGlu(DOTA)8-LA4-AuNP were more stable to aggregation in vitro than DOTA-PEG-LA-AuNP and both forms of AuNP were more stable to thiol challenge than DOTA-PEG-OPSS-AuNP. PEG-pGlu((177)Lu-DOTA)8-LA4 was the most stable in plasma. Whole body elimination of (177)Lu was most rapid for mice injected with (177)Lu-DOTA-PEG-OPSS-AuNP. Urinary excretion accounted for >90% of eliminated (177)Lu. All (177)Lu-MCP-AuNP accumulated in the liver and spleen. Liver uptake was lowest for PEG-pGlu((177)Lu-DOTA)8-LA4-AuNP but these AuNP exhibited the greatest spleen uptake. There were differences in Au and (177)Lu in the liver for PEG-pGlu((177)Lu-DOTA)8-LA4-AuNP. These differences were not correlated with in vitro stability of the (177)Lu-MCP-AuNP. We conclude that conjugation of AuNP with PEG-pGlu((177)Lu-DOTA)8-LA4 via a multithiol

  17. Determination of human absorbed dose of cocktail of 153Sm/177Lu-EDTMP, based on biodistribution data in rats

    The aim of this work was to estimate the absorbed dose due to compositional radiopharmaceutical of 153Sm/177Lu-EDTMP in human organs based on biodistribution data of rats by using OLINDA/EXM software. The absorbed dose was determined by the Radiation Dose Assessment Resource (RADAR) formulation after calculating cumulated activities in each organ. The results show that the organs that received the highest absorbed dose were the bone surface and red marrow (1.51 and 7.99 mGy/ MBq for 153Sm, and 1.98 and 10.76 mGy/MBq for 177Lu, respectively). According to the results, using of cocktail of 153Sm/177Lu-EDTMP has considerable characteristics as compared to 153Sm-EDTMP and 177Lu-EDTMP alone. (author)

  18. A novel 177Lu-labeled porphyrin for possible use in targeted tumor therapy

    Introduction: Porphyrin and its derivatives exhibit inherent affinity for localization in tumors. Hence, porphyrin derivatives radiolabeled with suitable therapeutic radionuclides could be envisaged as potential agents for targeted tumor therapy. In this direction, a water-soluble porphyrin derivative, viz., 5,10,15,20-tetrakis[4-carboxymethyleneoxyphenyl]porphyrin was synthesized in-house and radiolabeled with 177Lu with an aim to prepare an agent for targeted tumor therapy. 177Lu is an attractive radionuclide for the development of targeted radiotherapeutic agents owing to its suitable decay characteristics [T1/2=6.73 d, Eβ(max)=0.49 MeV, Eγ=208 keV (11%)], comparatively longer half-life and ease of production with high specific activity. Methods: 177Lu was produced by irradiation of enriched Lu2O3 (64.3% 176Lu) at a thermal neutron flux of 1x1014 n/cm2.s for 14 d. The porphyrin was coupled to a suitable chelator, namely, p-aminobenzyl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid for complexation with 177Lu. The radiolabeling was achieved by incubating 50 μg of the conjugate with 177LuCl3 (200 ng Lu) in acetate buffer (pH ∼5) at 50oC for 1 h. The radiolabeled conjugate was characterized by high-performance liquid chromatography and its biological efficacy was studied in Swiss mice bearing fibrosarcoma tumors. Results: 177Lu was obtained with a specific activity of ∼550 TBq/g and radionuclidic purity of 99.98%. The 177Lu-labeled porphyrin conjugate was obtained with 99% radiochemical purity and it exhibited good in vitro stability. Biodistribution studies revealed good tumor uptake (2.01% IA/g) within 3 h post injection (p.i.) with >94% injected activity exhibiting renal clearance. No significant accumulation of activity was observed in any of the vital organs/tissue. The tumor/blood and tumor/muscle ratios were 2.89 and 16.80, respectively, at 3 h p.i. and further increased till 2 days p.i. up to which the studies continued. Serial

  19. 177Lu-DOTMP: a viable agent for palliative radiotherapy of painful bone metastasis

    The suitable nuclear decay characteristics [T1/2 = 6.73 d, Eβ(max) = 497 keV, Eγ = 113 keV (6.4%), 208 keV (11%)] as well as the feasibility of large-scale production with adequate specific activity and radionuclidic purity using a moderate flux reactor are important attributes towards 177Lu to be considered as a promising radionuclide for palliative care in painful bone metastasis. The present study describes the preparation of 177Lu complex of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene phosphonic acid (DOTMP) and its preliminary biological evaluation in animal models with an aim to proposing it as a viable radiopharmaceutical for bone pain palliation. The choice DOTMP as the polyaminophosphonic acid carrier ligand is based on the enhanced thermodynamic stability and kinetic inertness of the metal-ligand complexes with macrocyclic chelators. 177Lu was produced with a specific activity of ∝ 12 GBq/mg (∝ 324 mCi/mg) and radionuclidic purity of 99.98% by irradiation of natural Lu2O3 target at a thermal neutron flux of ∝ 6 x 1013 n/cm2 s for 21 d. 177Lu-DOTMP complex was prepared in high yield and excellent radiochemical purity (> 99%) using DOTMP synthesized and characterized in-house. The complex exhibited excellent in-vitro stability at room temperature. Biodistribution studies in Wistar rats showed rapid skeletal accumulation of the injected activity [(1.60±0.19)% per gram in femur at 3 h post-injection] with fast clearance from blood and minimal uptake in any of the major organs. Scintigraphic studies carried out in normal Wistar rats and New Zealand white rabbits also demonstrated significant accumulation of the agent in skeleton and almost no retention in any other vital organs. (orig.)

  20. Transcriptional response of kidney tissue after 177Lu-octreotate administration in mice

    Introduction: The kidneys are one of the main dose limiting organs in 177Lu-octreotate therapy of neuroendocrine tumors. Therefore, biomarkers for radiation damage would be of great importance in this type of therapy. The purpose of this study was to investigate the absorbed dose dependency on early transcriptional changes in the kidneys from 177Lu-octreotate exposure. Methods: Female Balb/c nude mice were i.v. injected with 1.3, 3.6, 14, 45 or 140 MBq 177Lu-octreotate. The animals were killed 24 h after injection followed by excision of the kidneys. The absorbed dose to the kidneys ranged between 0.13 and 13 Gy. Total RNA was extracted from separated renal tissue samples, and applied to Illumina MouseRef-8 Whole-Genome Expression Beadchips to identify regulated transcripts after irradiation. Nexus Expression 2.0 and Gene Ontology terms were used for data processing and to determine affected biological processes. Results: Distinct transcriptional responses were observed following 177Lu-octreotate administration. A higher number of differentially expressed transcripts were observed in the kidney medulla (480) compared to cortex (281). In addition, 39 transcripts were regulated at all absorbed dose levels in the medulla, compared to 32 in the cortex. Three biological processes in the cortex and five in the medulla were also shared by all absorbed dose levels. Strong association to metabolism was found among the affected processes in both tissues. Furthermore, an association with cellular and developmental processes was prominent in kidney medulla, while transport and immune response were prominent in kidney cortex. Conclusion: Specific biological and dose-dependent responses were observed in both tissues. The number of affected transcripts and biological processes revealed distinct response differences between the absorbed doses delivered to the tissues

  1. In Vivo Measurement and Characterization of a Novel Formulation of [177Lu]-DOTA-Octreotate

    Dale Bailey

    2016-01-01

    Full Text Available Objective(s:Lutetium-177 can be made with high specific activity and with no other isotopes of lutetium present, referred to as “No Carrier Added” (NCA 177Lu. We have radiolabelled DOTA-conjugated peptide DOTA‐(Tyr3‐octreotate with NCA 177Lu (“NCA-LuTATE” and used it in nearly 40 therapeutic administrations for subjects with neuroendocrine tumours or meningiomas. In this paper, we report on our initial studies on aspects of the biodistribution and dosimetry of NCA-LuTATE from gamma camera 2D whole body (WB and quantitative 3D SPECT (qSPECT 177Lu imaging. Methods: Thirteen patients received 39 NCA-LuTATE injections. Extensive WB planar and qSPECT imaging was acquired at approximately 0.5, 4, 24 and 96 h to permit estimates of clearance and radiation dose estimation using MIRD-based methodology (OLINDA-EXM. Results:The average amount of NCA-Lutate administered per cycle was 7839±520 MBq. Bi-exponential modelling of whole body clearance showed half lives for the fast & slow components of t½=2.1±0.6 h and t½=58.1±6.6 h respectively. The average effective dose to kidneys was 3.1±1.0 Gy per cycle. In eight patients completing all treatment cycles the average total dose to kidneys was 11.7±3.6 Gy. Conclusions: We have shown that NCA-LuTATE has an acceptable radiation safety profile and is a suitable alternative to Carrier-Added 177Lu formulations. The fast component of the radiopharmaceutical clearance was closely correlated with baseline renal glomerular filtration rate, and this had an impact on radiation dose to the kidneys. In addition, it has less radioactive waste issues and requires less peptide per treatment.

  2. Long-term toxicity of [177Lu-DOTA0,Tyr3]octreotate in rats

    Studies on peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues have shown promising results with regard to tumour control. The efficacy of PRRT is limited by uptake and retention in the proximal tubules of the kidney, which might lead to radiation nephropathy. We investigated the long-term renal toxicity after different doses of [177Lu-DOTA0,Tyr3]octreotate and the effects of dose fractionation and lysine co-injection in two tumour-bearing rat models. Significant renal toxicity was detected beyond 100 days after start of treatment as shown by elevated serum creatinine and proteinuria. Microscopically, tubules were strongly dilated with flat epithelium, containing protein cylinders. Creatinine levels rose significantly after 555 MBq [177Lu-DOTA0,Tyr3]octreotate, but were significantly lower after 278 MBq (single injection) or two weekly doses of 278 MBq. Renal damage scores were maximal after 555 MBq and significantly lower in the 278 and 2 x 278 MBq groups. Three doses of 185 MBq [177Lu-DOTA0,Tyr3]octreotate with intervals of a day, a week or a month significantly influenced serum creatinine (469±18, 134±70 and 65±15 μmol/l, respectively; p177Lu-DOTA0,Tyr3]octreotate resulted in severe renal damage in rats as indicated by proteinuria, elevated serum creatinine and histological damage. This damage was dose dependent and became overt between 100 and 200 days after treatment. Dose fractionation had significant beneficial effects on kidney function. Also, lysine co-injection successfully prevented functional damage. (orig.)

  3. [177Lu]-DOTA0-Tyr3-octreotate: A Potential Targeted Radiotherapeutic for the Treatment of Medulloblastoma

    Vaidyanathan, Ganesan; Affleck, Donna J.; Zhao, Xiao-Guang; Keir, Stephen T.; Zalutsky, Michael R.

    2010-01-01

    Medulloblastoma, the most common pediatric brain tumor, is difficult to treat because conventional therapeutic approaches result in significant toxicity to normal central nervous system tissues, compromising quality of life. Given the fact that medulloblastomas express the somatostatin subtype 2 receptor, [177Lu-DOTA0,Tyr3]octreotate ([177Lu]DOTA-TATE) could be a potentially useful targeted radiotherapeutic for the treatment of this malignancy. The current study was undertaken to evaluate thi...

  4. Somatostatin-based radiopeptide therapy with [177Lu-DOTA]-TOC versus [90Y-DOTA]-TOC in neuroendocrine tumours

    Somatostatin-based radiopeptide treatment is generally performed using the β-emitting radionuclides 90Y or 177Lu. The present study aimed at comparing benefits and harms of both therapeutic approaches. In a comparative cohort study, patients with advanced neuroendocrine tumours underwent repeated cycles of [90Y-DOTA]-TOC or [177Lu-DOTA]-TOC until progression of disease or permanent adverse events. Multivariable Cox regression and competing risks regression were employed to examine predictors of survival and adverse events for both treatment groups. Overall, 910 patients underwent 1,804 cycles of [90Y-DOTA]-TOC and 141 patients underwent 259 cycles of [177Lu-DOTA]-TOC. The median survival after [177Lu-DOTA]-TOC and after [90Y-DOTA]-TOC was comparable (45.5 months versus 35.9 months, hazard ratio 0.91, 95 % confidence interval 0.63-1.30, p = 0.49). Subgroup analyses revealed a significantly longer survival for [177Lu-DOTA]-TOC over [90Y-DOTA]-TOC in patients with low tumour uptake, solitary lesions and extra-hepatic lesions. The rate of severe transient haematotoxicities was lower after [177Lu-DOTA]-TOC treatment (1.4 vs 10.1 %, p = 0.001), while the rate of severe permanent renal toxicities was similar in both treatment groups (9.2 vs 7.8 %, p = 0.32). The present results revealed no difference in median overall survival after [177Lu-DOTA]-TOC and [90Y-DOTA]-TOC. Furthermore, [177Lu-DOTA]-TOC was less haematotoxic than [90Y-DOTA]-TOC. (orig.)

  5. β-radiation exposure with 188Re-labelled pharmaceuticals

    Aim: The number of therapies with radiopharmaceuticals labelled with 188Re is increasing requiring the documentation of the beta radiation exposure Hp(0.07) of the staff at all working and production sites and during the application and follow-up of the patient according to the new German Radiation Protection Law (StrlSchV). However, data for β-radiation exposure are rare. Therefore, we determined the personal dose Hp(0.07) of the skin of the hands handling 188Re radiopharmaceuticals to identify steps of high radiation exposure and to optimize working conditions. Method: Thermoluminescence dosimeters (TLD 100) were fixed to the fingertips of the radiochemist, the physician and the nurse and compared to official ring dosimeters. In addition, to monitor radiation exposure continuously readable electronic beta- and gamma dosimeters EPD (Siemens) were used. At eight days in which therapies were performed these readings were evaluated. Results: Considering one therapy with a 188Re-labelled radiopharmaceutical the middle finger of the radiochemist (production) and the physician (application) showed a radiation burden of 894 and 664 μSv/GBq, respectively. The cumulative dose of the fingertips after eight days of therapy was 249 and 110 mSv for the radiochemist and physician, respectively. A cumulative finger dose after eight days of therapy of 17 and 39 μSv/GBq was found for physician and nurse leading to a Hp(0.07) of 3 and 6 mSv, respectively. Preparing the radiopharmaceutical labelled with 20 GBq of 188Re the reading of the personal electronic dosimeter of the radiochemist showed a γ-dose rate Hp(10) of 55 μSv/h and a β-dose rate Hp(0.07) of 663 μSv/h which are obviously not representative for the true radiation dose to the skin of the fingertips. Conclusion: During therapy with 188Re-labelled radiopharmaceuticals the true radiation dose to the skin of the finger tips exceeds by far the readings of the official ring dosimeters as well as the continuously

  6. Targeted radiotherapy with 177 Lu-DOTA-TATE in athymic mice with induced pancreatic malignant tumours

    Malignant pancreas tumours induced in athymic mice are a good model for peptide receptor targeted radiotherapy. The objective of this research was to estimate pancreatic tumour absorbed radiation doses after administration of 177Lu-DOTA-TATE in mice as a therapeutic radiopharmaceutical that could be used in humans. AR42J murine pancreas cancer cells expressing somatostatin receptors, were implanted in athymic mice (n=18) to obtain the 177Lu-DOTA-TATE biokinetics and dosimetry. To estimate its therapeutic efficacy 87 MBq were injected in a tail vein of 3 mice and 19 days p.i. there were a partial relapse. There was an epithelial and sarcoma mixed tumour in the kidneys of mouse III. The absorbed dose to tumour, kidney and pancreas was 50.5 ± 7.2 Gy, 17.5 ± 2.5 Gy and 12.6 ± 2.3 Gy respectively. These studies justify further therapeutic and dosimetry estimations to ensure that 177Lu-DOTA-TATE will act as expected in man considering its kidney radiotoxicity. (Author)

  7. 177Lu-DOTA-lanreotide: a novel tracer as a targeted agent for tumor therapy

    177Lu of specific activity ∼100-110 TBq/g and radionuclidic purity of ∼100% was obtained by irradiation of enriched Lu2O3 (60.6% 176Lu) target for 7 days at a thermal neutron flux of 3x1013n/cm2/sec. The 177Lu labeling of a macrocyclic bifunctional chelating agent viz. 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) has been extensively studied. Lanreotide, [β-naphthyl-Ala-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH2] a disulfide-linked cyclic octapeptide and a somatostatin analog, reported to bind with a wide variety of tumors expressing somatostatin receptors, was conjugated with DOTA. The peptide-BFCA conjugate was characterized with the help of high-resolution two-dimensional proton NMR spectroscopy. The 177Lu labeling of the DOTA-lanreotide conjugate has been standardized to give a radiolabeling yield of 85%. The tracer showed specific binding with A-431 human epidermoid carcinoma and IMR-32 human brain neuroblastoma cells

  8. Application of analytic methodologies for image quantification in neuroendocrine tumor therapy with 177Lu-DOTA

    Neuroendocrine tumors have annual incidence of 1 to 2 cases per one hundred thousand inhabitants. The 177Lu-DOTA-octreotate treatments in 3 or 4 cycles has been effective in controlling disease progression and, in some cases, promote tumor remission. To estimate radiation side effects in healthy organs, image quantification techniques have been broadcast for individualized patient dosimetry. In this paper, image data processing methods are presented to allowing comparisons between different image conjugate views, combined with attenuation correction and system sensitivity. Images were acquired 24, 72 and 192 h after administration of 74 GBq of 177Lu-DOTA using a dual-head gamma camera detection system and they were evaluated with ImageJ software. 4 female patients underwent to two cycles of treatment. The kidneys, liver and whole-body regions of interest were separately assessed by 4 techniques for counts method and 12 techniques for pixel intensity method, considering the main photopeak separately and aided by the attenuation correction map and adjacent windows to photopeak energy. The pixel intensity method was combined with mathematical correction for pixels with null value. The results obtained by the two methods were strongly correlated (r>0.9) (p0.05) was found between the treatment cycles. In conclusion, the pixel intensity method is faster and allows macros, minimizing operator error, and may optimize dosimetry in tumor therapies with 177Lu-DOTA-octreotate. (author)

  9. Labelling of aminomethylenephosphonate derivatives with generator-produced 188Re and their stability

    In this study, the labelling of aminomethylenephosphonate derivatives (EDTMP Ethylenediamine-N,N,N',N' -tetrakis(methylenephosphonic acid), EDBMP - Ethylenediamine- N,N'-bis(methylenephosphonic acid) and NTMP - nitrilotris(methylenephosphonic acid)) with carrier-free 188Re from the 188W/188Re generator was investigated in detail. Stannous chloride was used as the reducing agent for the reduction of rhenium. The labelling studies were carried out by mixing all the solutions (ligand, I-ascorbic acid, a solution for pH adjustment, 188Re and stannous chloride) in a vial. The dependence of the labelling yield upon the reaction conditions such as the concentrations of the reducing agent and the ligand (aminomethylenephosphonate), pH, temperature and the addition of a carrier was examined. The stability of the 188Re complex against pH change and dilution with saline was also studied. It was found that the formation condition of the 188Re complex, that is the temperature, pH and the addition of a carrier, influenced the stability of 188Re complex. The carrier-added 188Re complex was more stable than the carrier-free 188Re complex. Furthermore, the stability decreased in the order 188Re-EDTMP > 188Re-EDBMP > 188Re-NTMP for the carrier-free 188Re complex

  10. Gamma camera calibration and validation for quantitative SPECT imaging with (177)Lu.

    D'Arienzo, M; Cazzato, M; Cozzella, M L; Cox, M; D'Andrea, M; Fazio, A; Fenwick, A; Iaccarino, G; Johansson, L; Strigari, L; Ungania, S; De Felice, P

    2016-06-01

    Over the last years (177)Lu has received considerable attention from the clinical nuclear medicine community thanks to its wide range of applications in molecular radiotherapy, especially in peptide-receptor radionuclide therapy (PRRT). In addition to short-range beta particles, (177)Lu emits low energy gamma radiation of 113keV and 208keV that allows gamma camera quantitative imaging. Despite quantitative cancer imaging in molecular radiotherapy having been proven to be a key instrument for the assessment of therapeutic response, at present no general clinically accepted quantitative imaging protocol exists and absolute quantification studies are usually based on individual initiatives. The aim of this work was to develop and evaluate an approach to gamma camera calibration for absolute quantification in tomographic imaging with (177)Lu. We assessed the gamma camera calibration factors for a Philips IRIX and Philips AXIS gamma camera system using various reference geometries, both in air and in water. Images were corrected for the major effects that contribute to image degradation, i.e. attenuation, scatter and dead- time. We validated our method in non-reference geometry using an anthropomorphic torso phantom provided with the liver cavity uniformly filled with (177)LuCl3. Our results showed that calibration factors depend on the particular reference condition. In general, acquisitions performed with the IRIX gamma camera provided good results at 208keV, with agreement within 5% for all geometries. The use of a Jaszczak 16mL hollow sphere in water provided calibration factors capable of recovering the activity in anthropomorphic geometry within 1% for the 208keV peak, for both gamma cameras. The point source provided the poorest results, most likely because scatter and attenuation correction are not incorporated in the calibration factor. However, for both gamma cameras all geometries provided calibration factors capable of recovering the activity in

  11. Subacute haematotoxicity after PRRT with {sup 177}Lu-DOTA-octreotate: prognostic factors, incidence and course

    Bergsma, Hendrik; Konijnenberg, Mark W.; Kam, Boen L.R.; Teunissen, Jaap J.M.; Kooij, Peter P.; Krenning, Eric P.; Kwekkeboom, Dik J. [Erasmus University Medical Center, Department of Nuclear Medicine, Rotterdam (Netherlands); Herder, Wouter W. de [Erasmus Medical Center, Department of Internal Medicine, Rotterdam (Netherlands); Franssen, Gaston J.H.; Eijck, Casper H.J. van [Erasmus Medical Center, Department of Surgery, Rotterdam (Netherlands)

    2016-03-15

    In peptide receptor radionuclide therapy (PRRT), the bone marrow (BM) is one of the dose-limiting organs. The accepted dose limit for BM is 2 Gy, adopted from {sup 131}I treatment. We investigated the incidence and duration of haematological toxicity and its risk factors in patients treated with PRRT with {sup 177}Lu-DOTA{sup 0}-Tyr{sup 3}-octreotate ({sup 177}Lu-DOTATATE). Also, absorbed BM dose estimates were evaluated and compared with the accepted 2 Gy dose limit. The incidence and duration of grade 3 or 4 haematological toxicity (according to CTCAE v3.0) and risk factors were analysed. Mean BM dose per unit (gigabecquerels) of administered radioactivity was calculated and the correlations between doses to the BM and haematological risk factors were determined. Haematological toxicity (grade 3/4) occurred in 34 (11 %) of 320 patients. In 15 of the 34 patients, this lasted more than 6 months or blood transfusions were required. Risk factors significantly associated with haematological toxicity were: poor renal function, white blood cell (WBC) count <4.0 x 10{sup 9}/l, age over 70 years, extensive tumour mass and high tumour uptake on the OctreoScan. Previous chemotherapy was not associated. The mean BM dose per administered activity in 23 evaluable patients was 67 ± 7 mGy/GBq, resulting in a mean BM dose of 2 Gy in patients who received four cycles of 7.4 GBq {sup 177}Lu-DOTATATE. Significant correlations between (cumulative) BM dose and platelet and WBC counts were found in a selected group of patients. The incidence of subacute haematological toxicity after PRRT with {sup 177}Lu-DOTATATE is acceptable (11 %). Patients with impaired renal function, low WBC count, extensive tumour mass, high tumour uptake on the OctreoScan and/or advanced age are more likely to develop grade 3/4 haematological toxicity. The BM dose limit of 2 Gy, adopted from {sup 131}I, seems not to be valid for PRRT with {sup 177}Lu-DOTATATE. (orig.)

  12. Subacute haematotoxicity after PRRT with 177Lu-DOTA-octreotate: prognostic factors, incidence and course

    In peptide receptor radionuclide therapy (PRRT), the bone marrow (BM) is one of the dose-limiting organs. The accepted dose limit for BM is 2 Gy, adopted from 131I treatment. We investigated the incidence and duration of haematological toxicity and its risk factors in patients treated with PRRT with 177Lu-DOTA0-Tyr3-octreotate (177Lu-DOTATATE). Also, absorbed BM dose estimates were evaluated and compared with the accepted 2 Gy dose limit. The incidence and duration of grade 3 or 4 haematological toxicity (according to CTCAE v3.0) and risk factors were analysed. Mean BM dose per unit (gigabecquerels) of administered radioactivity was calculated and the correlations between doses to the BM and haematological risk factors were determined. Haematological toxicity (grade 3/4) occurred in 34 (11 %) of 320 patients. In 15 of the 34 patients, this lasted more than 6 months or blood transfusions were required. Risk factors significantly associated with haematological toxicity were: poor renal function, white blood cell (WBC) count <4.0 x 109/l, age over 70 years, extensive tumour mass and high tumour uptake on the OctreoScan. Previous chemotherapy was not associated. The mean BM dose per administered activity in 23 evaluable patients was 67 ± 7 mGy/GBq, resulting in a mean BM dose of 2 Gy in patients who received four cycles of 7.4 GBq 177Lu-DOTATATE. Significant correlations between (cumulative) BM dose and platelet and WBC counts were found in a selected group of patients. The incidence of subacute haematological toxicity after PRRT with 177Lu-DOTATATE is acceptable (11 %). Patients with impaired renal function, low WBC count, extensive tumour mass, high tumour uptake on the OctreoScan and/or advanced age are more likely to develop grade 3/4 haematological toxicity. The BM dose limit of 2 Gy, adopted from 131I, seems not to be valid for PRRT with 177Lu-DOTATATE. (orig.)

  13. Study on the preparation and stability of 188Re biomolecules via EHDP

    A direct labelling technique via ethane-1-hydroxy-1,1-diphosphonic acid (EHDP) as a weak competing ligand was developed for the preparation of several biomolecules: 188 Re-monoclonal antibody ior cea1 against carcinoembryonic antigen (188 Re-MoAb), biotinylated 188Re-MoAb (188 Re-MoAb-biotin), 188 Re-polyclonal IgG (188 Re-IgG), 188 Re-peptide (somatostatine analogue peptide b-(2-naphtyl)-D-Ala-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-amide), 188 Re-MoAb fragments (188 Re-F(ab')2) and biotinylated 188 Re-F(ab')2 (188 Re-F(ab')2-biotin). The reaction conditions such as pH, temperature, weak ligand concentration and stannous chloride concentration were optimized during the radiolabelling of each biomolecule. Before the labelling procedure, disulphide bridge groups of the biomolecules were reduced with 2-mercaptoethanol (2-ME). To obtain 188 Re labelled antibodies and peptides in high radiochemical yields (>90%) via EHDP, it was necessary to use acidic conditions and a high concentration of stannous chloride to allow the redox reaction Re+7→Re+5:Re+4. The labelling of MoAb and F(ab')2 with 188Re via EHDP was also evaluated employing a pretargeted technique by avidin-biotin strategy in normal mice, demonstrating that the 188Re-labelled biotinylated antibodies are stable complexes in vivo. The 188Re-peptide complex prepared by this method, was stable for 24 h and no radiolytic degradation was observed. (author)

  14. Comparative biodistributions and dosimetry of [177Lu]DOTA-anti-bcl-2-PNA-Tyr3-octreotate and [177Lu]DOTA-Tyr3-octreotate in a mouse model of B-cell lymphoma/leukemia

    Introduction: The B-cell lymphoma/leukemia-2 (bcl-2) proto-oncogene in non-Hodgkin’s lymphoma (NHL) is a dominant inhibitor of apoptosis. We developed a 177Lu-labeled bcl-2 antisense peptide nucleic acid (PNA)–peptide conjugate designed for dual modality NHL therapy, consisting of a radiopharmaceutical capable of simultaneously down-regulating apoptotic resistance and delivering cytotoxic internally emitted radiation. Methods: DOTA-anti-bcl-2-Tyr3-octreotate was synthesized, labeled with 177Lu, and purified using RP-HPLC. The PNA–peptide conjugate was evaluated in Mec-1 NHL-bearing mice and compared to [177Lu]DOTA-Tyr3-octreotate in biodistribution and excretion studies. These data were then used to generate in vivo dosimetry models. Results: The PNA–peptide conjugate was readily prepared and radiolabeled in high yield and radiochemical purity. An in vivo blocking study determined that administration of 50 μg of non-radioactive PNA–peptide was the optimal mass for maximum delivery to the tumor. Based on that result, a dosing regimen of 177Lu-PNA–peptide, for radiologic effect, followed by the optimal mass of non-radioactive compound, for antisense effect, was designed. Using that dosing regimen, biodistribution of the PNA–peptide showed uptake in the tumor with minimal washout over a 4-day period. Uptakes in receptor-positive normal organs were low and displayed nearly complete washout by 24 h. Dosimetry models showed that the tumor absorbed dose of the PNA–peptide conjugate was approximately twice that of the peptide-only conjugate. Conclusions: Biodistribution data showed specific tumor targeting of the 177Lu-labeled PNA–peptide compound with minimal receptor-positive normal tissue uptake when compared to [177Lu]DOTA-Tyr3-octreotate. In vivo dosimetry models predicted a more favorable tumor absorbed dose from [177Lu]DOTA-anti-bcl-2-Tyr3-octreotate

  15. Studies on {sup 177}Lu-labeled methylene diphosphonate as potential bone-seeking radiopharmaceutical for bone pain palliation

    Abbasi, Imtiaz Ahmed, E-mail: imtiaz_abbasi@yahoo.co

    2011-04-15

    Objective: {sup 99m}Tc-MDP (technetium-99{sup m}-labeled methylene diphosphonate) has been widely used as a radiopharmaceutical for bone scintigraphy in cases of metastatic bone disease. {sup 177}Lu is presently considered as an excellent radionuclide for developing bone pain palliation agents. No study on preparing a complex of {sup 177}Lu with MDP has been reported yet. Based on these facts, it was hypothesized that a bone-seeking {sup 177}Lu-MDP (lutetium-177-labeled MDP) radiopharmaceutical could be developed as an agent for palliative radiotherapy of bone pain due to skeletal metastases. Biodistribution studies after intravenous injection of {sup 177}Lu-MDP complex in rats may yield important information to assess its potential for clinical use as a bone pain palliation agent for the treatment of bone metastases. Methods: {sup 177}Lu was produced by irradiating natural Lu{sub 2}O{sub 3} (10 mg) target at a thermal flux {approx}8.0x10{sup 13} n/cm{sup 2} per second for 12 h in the swimming pool-type reactor.{sup 177}Lu was labeled with MDP by adding nearly 37 MBq (1.0 mCi) of {sup 177}LuCl{sub 3} to a vial containing 10 mg MDP. The radiochemical purity and labeling efficiencies were determined by thin layer chromatography. Labeling of {sup 177}Lu with MDP was optimized, and one sample was subjected to high-performance liquid chromatography (HPLC) analysis. Twelve Sprague-Dawley rats were injected with 18.5 MBq (0.5 mCi). {sup 177}Lu-MDP in a volume of 0.1 ml was injected intravenously and then sacrificed at 2 min, 1 h, 2 h and 22 h (three rats at each time point) after injection. Samples of various organs were separated, weighed and measured for radioactivity and expressed as percent uptake of injected dose per gram. Bioevaluation studies with rats under gamma-camera were also performed to verify the results. Results: The quality control using thin layer chromatography has shown >99% radiochemical purity of {sup 177}Lu-MDP complex. Chromatography with Whatman 3

  16. Labelling of aminomethylenephosphonate derivatives with generator-produced {sup 188}Re and their stability

    Hashimoto, K. [Japan Atomic Energy Research Insttitute, Tokai-mura, Ibaraki-ken, (Japan). Department of Radioisotopes

    1997-10-01

    In this study, the labelling of aminomethylenephosphonate derivatives (EDTMP Ethylenediamine-N,N,N`,N` -tetrakis(methylenephosphonic acid), EDBMP - Ethylenediamine- N,N`-bis(methylenephosphonic acid) and NTMP - nitrilotris(methylenephosphonic acid)) with carrier-free {sup 188}Re from the {sup 188}W/{sup 1}8{sup 8R}e generator was investigated in detail. Stannous chloride was used as the reducing agent for the reduction of rhenium. The labelling studies were carried out by mixing all the solutions (ligand, I-ascorbic acid, a solution for pH adjustment, {sup 188}Re and stannous chloride) in a vial. The dependence of the labelling yield upon the reaction conditions such as the concentrations of the reducing agent and the ligand (aminomethylenephosphonate), pH, temperature and the addition of a carrier was examined. The stability of the {sup 188}Re complex against pH change and dilution with saline was also studied. It was found that the formation condition of the {sup 188}Re complex, that is the temperature, pH and the addition of a carrier, influenced the stability of {sup 188}Re complex. The carrier-added {sup 188}Re complex was more stable than the carrier-free {sup 188}Re complex. Furthermore, the stability decreased in the order {sup 188}Re-EDTMP > {sup 188}Re-EDBMP > {sup 188}Re-NTMP for the carrier-free {sup 188}Re complex 20 refs., 12 figs.

  17. Intratumoral injection of 188Re labeled cationic polyethylenimine conjugates: a preliminary report.

    Kim, Eun-Mi; Jeong, Hwan-Jeong; Heo, Young-Jun; Moon, Hyung-Bae; Bom, Hee-Seung; Kim, Chang-Guhn

    2004-10-01

    188Re (Rhenium) is easily obtained from an in-house 188W/188Re generator that is similar to the current 99Mo/99mTc generator, making it very convenient for clinical use. This characteristic makes this radionuclide a promising candidate as a therapeutic agent. Polyethylenimine (PEI) is a cationic polymer and has been used as a gene delivery vector. Positively charged materials interact with cellular blood components, vascular endothelium, and plasma proteins. In this study, the authors investigated whether intratumoral injection of 188Re labeled transferrin (Tf)-PEI conjugates exert the effect of radionuclide therapy against the tumor cells. When the diameters of the Ramos lymphoma (human Burkitt's lymphoma) xenografted tumors reached approximately 1 cm, 3 kinds of 188Re bound compounds (HYNIC-PEI-Tf, HYNIC-PEI, 188Re perrhenate) were injected directly into the tumors. There were increases in the retention of 188Re inside the tumor when PEI was incorporated with 188Re compared to the use of free 188Re. The 188Re HYNIC-Tf-PEI showed the most retention inside the tumor (retention rate=approximately 97%). H&E stain of isolated tumor tissues showed that 188Re labeled HYNIC-PEI-Tf caused extensive tumor necrosis. These results support 188Re HYNIC-PEI-Tf as being a useful radiopharmaceutical agent to treat tumors when delivered by intratumoral injection. PMID:15483337

  18. Experimental study of 188Re-BAC5 radioimmunotherapy on nasopharyngeal carcinoma

    The feasibility of radioimmunotherapy for NPC with 188Re-BAC5, a kind of monoclonal antibody to NPC, was investigated. The 188Re-BAC5 was prepared by direct labeling method and its biological activity was determined. The MTT method was used to determine the inhibition effect of the 188Re-BAC5 on CNE-2 cell line culture, and the destruction effect on CNE-2 multicellular spheroids model was also observed. The control group were 188Re-BSA and 188ReO4-. The biological activity of BAC5 was 1:780000 after purification. The labeling yield of 188Re-BAC5 was above 80%. The immuno-activity of 188Re-BAC5 was 61% ± 15%. The results of MTT showed that the inhibition effect of 188Re-BAC5 group was much stronger than the control group (P188Re-BAC5 had a obvious destruction effect on spheroids, and there was a significant difference between 188Re-BAC5 and the control group. In conclusion, 188Re-BAC5 may serve a possible way in the treatment of NPC in the near future

  19. Labeling Lanreotide with 125I and 188Re

    Lanreotide is a new somatostatin analogue. It can bind to human somatostatin receptor (hSSTR) subtype 2 through 5 with high affinity and to hSSTR subtype I with low affinity. We investigate labeling condition, quality control and stability in vitro of 125I-Lanreotide and 188Re-lanreotide respectively. (A) Lanreotide is labeled with 125I using Chloramine T. The effect of reaction condition (such as reaction time, pH value, Lanreotide amount, quantity of Chloramine T and reaction volume) on labeling yield is investigated in detail. (B) The labeling yield and radiochemical purity (RP) is measured with paper chromatography (PC) and Sep-Pak C18 Cartridge. (C) The stability of 125I-Lanreotide in vitro is investigated by labeling compound incubating for 48 hours at 37 deg C in the 0.9% sodium chloride solution and RP is tested by PC at specific time intervals. (D) Lanreotide is labeled directly with 188Re via the mixture of citrate and tartate using stannous chloride as reduced agent. The influence of reaction conditions such as pH, temperature, amount of stannous chloride, amount of Lanreotide and reaction time on labeling yield is investigated in detail. At the time, the stability in vitro quality control and animal test are evaluated

  20. 177Lu-DOTA-HH1, a novel anti-CD37 radio-immunoconjugate: a study of toxicity in nude mice.

    Ada H V Repetto-Llamazares

    Full Text Available CD37 is an internalizing B-cell antigen expressed on Non-Hodgkin lymphoma (NHL and chronic lymphocytic leukemia cells (CLL. The anti-CD37 monoclonal antibody HH1 was conjugated to the bifunctional chelator p-SCN-Bn-DOTA and labelled with the beta-particle emitting radionuclide 177Lu creating the radio-immunoconjugate (RIC 177Lu-DOTA-HH1 (177Lu-HH1, trade name Betalutin. The present toxicity study was performed prior to initiation of clinical studies with 177Lu-HH1.Nude mice with or without tumor xenografts were treated with 50 to 1000 MBq/kg 177Lu- HH1 and followed for clinical signs of toxicity up to ten months. Acute, life threatening bone marrow toxicity was observed in animals receiving 800 and 1000 MBq/kg 177Lu-HH1. Significant changes in serum concentrations of liver enzymes were evident for treatment with 1000 MBq/kg 177Lu-HH1. Lymphoid depletion, liver necrosis and atrophy, and interstitial cell hyperplasia of the ovaries were also observed for mice in this dose group.177Lu-DOTA-HH1 was well tolerated at dosages about 10 times above those considered relevant for radioimmunotherapy in patients with B-cell derived malignancies.The toxicity profile was as expected for RICs. Our experimental results have paved the way for clinical evaluation of 177Lu-HH1 in NHL patients.

  1. Synthesis and evaluation of a new bifunctional NETA chelate for molecular targeted radiotherapy using90Y or177Lu

    Introduction: Therapeutic potential of β-emitting cytotoxic radionuclides 90Y and 177Lu has been demonstrated in numerous preclinical and clinical trials. A bifunctional chelate that can effectively complex with the radioisotopes is a critical component for molecular targeted radiotherapy 90Y and 177Lu. A new bifunctional chelate 5p-C-NETA with a relatively long alkyl spacer between the chelating backbone and the functional unit for conjugation to a tumor targeting moiety was synthesized. 5p-C-NETA was conjugated to a model targeting moiety, a cyclic Arg-Gly-Asp-D-Tyr-Lys (RGDyK) peptide binding integrin αvβ3 protein overexpressed on various cancers. 5p-C-NETA was conjugated to c(RGDyK) peptide and evaluated for potential use in molecular targeted radiotherapy of 90Y and 177Lu. Methods: 5p-C-NETA conjugated with c(RGDyK) was evaluated in vitro for radiolabeling, serum stability, binding affinity, and the result of the in vitro studies of 5p-C-NETA-c(RGDyK) was compared to that of 3p-C-NETA-c(RGDyK). 177Lu-5p-C-NETA-c(RGDyK) was further evaluated for in vivo biodistribution using gliobastoma bearing mice. Result: The new chelate rapidly and tightly bound to a cytotoxic radioisotope for cancer therapy, 90Y or 177Lu with excellent radiolabeling efficiency and maximum specific activity under mild condition (> 99%, RT, < 1 min). 90Y- and 177Lu-radiolabeled complexes of the new chelator remained stable in human serum without any loss of the radiolanthanide for 14 days. Introduction of the tumor targeting RGD moiety to the new chelator made little impact on complexation kinetics and stability with 90Y or 177Lu. 177Lu-radiolabeled 5p-C-NETA-c(RGDyK) conjugate was shown to target tumors in mice and produced a favorable in vivo stability profile. Conclusion: The results of in vitro and in vivo evaluation suggest that 5p-C-NETA is an effective bifunctional chelate of 90Y and 177Lu that can be applied for generation of versatile molecular targeted radiopharmaceuticals

  2. Comparative efficacy of 177Lu and 90Y for Anti-CD20 Pretargeted Radioimmunotherapy in Murine Lymphoma Xenograft Models

    Purpose Pretargeted radioimmunotherapy (PRIT) is a multi-step method of selectively delivering high doses of radiotherapy to tumor cells while minimizing exposure to surrounding tissues. Yttrium-90 (90Y) and lutetium-177 (177Lu) are two of the most promising beta-particle emitting radionuclides used for radioimmunotherapy, which despite having similar chemistries differ distinctly in terms of radiophysical features. These differences may have important consequences for the absorbed dose to tumors and normal organs. Whereas 90Y has been successfully applied in a number of preclinical and clinical radioimmunotherapy settings, there have been few published pretargeting studies with 177Lu. We therefore compared the therapeutic potential of targeting either 90Y or 177Lu to human B-cell lymphoma xenografts in mice. Methods Parallel experiments evaluating the biodistribution, imaging, dosimetry, therapeutic efficacy, and toxicity were performed in female athymic nude mice bearing either Ramos (Burkitt lymphoma) or Granta (mantle cell lymphoma) xenografts, utilizing an anti-CD20 antibodystreptavidin conjugate (1F5-SA) and an 90Y- or 177Lu-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-biotin second step reagent. Results The two radionuclides displayed comparable biodistributions in tumors and normal organs; however, the absorbed radiation dose delivered to tumor was more than twice as high for 90Y (1.3 Gy/MBq) as for 177Lu (0.6 Gy/MBq). More importantly, therapy with 90Y-DOTAbiotin was dramatically more effective than with 177Lu-DOTA-biotin, with 100% of Ramos xenograft-bearing mice cured with 37 MBq 90Y, whereas 0% were cured using identical amounts of 177Lu-DOTA-biotin. Similar results were observed in mice bearing Granta xenografts, with 80% of the mice cured with 90Y-PRIT and 0% cured with 177Lu-PRIT. Toxicities were comparable with both isotopes. Conclusion 90Y was therapeutically superior to 177Lu for streptavidin-biotin PRIT approaches in

  3. Comparative efficacy of 177Lu and 90Y for anti-CD20 pretargeted radioimmunotherapy in murine lymphoma xenograft models.

    Sofia H L Frost

    Full Text Available Pretargeted radioimmunotherapy (PRIT is a multi-step method of selectively delivering high doses of radiotherapy to tumor cells while minimizing exposure to surrounding tissues. Yttrium-90 (90Y and lutetium-177 (177Lu are two of the most promising beta-particle emitting radionuclides used for radioimmunotherapy, which despite having similar chemistries differ distinctly in terms of radiophysical features. These differences may have important consequences for the absorbed dose to tumors and normal organs. Whereas 90Y has been successfully applied in a number of preclinical and clinical radioimmunotherapy settings, there have been few published pretargeting studies with 177Lu. We therefore compared the therapeutic potential of targeting either 90Y or 177Lu to human B-cell lymphoma xenografts in mice.Parallel experiments evaluating the biodistribution, imaging, dosimetry, therapeutic efficacy, and toxicity were performed in female athymic nude mice bearing either Ramos (Burkitt lymphoma or Granta (mantle cell lymphoma xenografts, utilizing an anti-CD20 antibody-streptavidin conjugate (1F5-SA and an 90Y- or 177Lu-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA-biotin second step reagent.The two radionuclides displayed comparable biodistributions in tumors and normal organs; however, the absorbed radiation dose delivered to tumor was more than twice as high for 90Y (1.3 Gy/MBq as for 177Lu (0.6 Gy/MBq. More importantly, therapy with 90Y-DOTA-biotin was dramatically more effective than with 177Lu-DOTA-biotin, with 100% of Ramos xenograft-bearing mice cured with 37 MBq 90Y, whereas 0% were cured using identical amounts of 177Lu-DOTA-biotin. Similar results were observed in mice bearing Granta xenografts, with 80% of the mice cured with 90Y-PRIT and 0% cured with 177Lu-PRIT. Toxicities were comparable with both isotopes.90Y was therapeutically superior to 177Lu for streptavidin-biotin PRIT approaches in these human lymphoma

  4. Development of 177Lu-DOTA-anti-CD20 for radioimmunotherapy

    Rituximab was successively labeled with 177Lu-lutetium chloride. 177Lu chloride was obtained by thermal neutron flux (4 x 1013 n cm-2 s-1) of natural Lu2O3 sample with a specific activity of 2.6-3 GBq/mg. The macrocyclic bifunctional chelating agent, N-succinimidyl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA-NHS) was prepared at 25 deg C using DOTA, N-hydroxy succinimide (NHS) in CH2Cl2. DOTA-rituximab was obtained by the addition of 1 mL of a rituximab pharmaceutical solution (5 mg/mL, in phosphate buffer, pH 7.8) to a glass tube pre-coated with DOTA-NHS (0.01-0.1 mg) at 25 deg C with continuous mild stirring for 15 h. Radiolabeling was performed at 37 deg C in 24 h. Radio-thin layer chromatography showed an overall radiochemical purity of >98% at optimized conditions (specific activity = 444 MBq/mg, labeling efficacy; 82%). The final isotonic 177Lu-DOTA-rituximab complex was checked by gel electrophoresis for structure integrity control. Radio-TLC was performed to ensure that only one species was present after filtration through a 0.22 μm filter. Preliminary biodistribution studies in normal rats were carried out to determine complex distribution of the radioimmunoconjugate up to 168 h. The biodistribution data were in accordance with other antiCD20 radioimmunoconjugates already reported. (author)

  5. DNA damage in blood lymphocytes in patients after {sup 177}Lu peptide receptor radionuclide therapy

    Eberlein, Uta; Bluemel, Christina; Buck, Andreas Konrad; Werner, Rudolf Alexander; Lassmann, Michael [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Nowak, Carina; Scherthan, Harry [Bundeswehr Institute of Radiobiology affiliated to the University of Ulm, Munich (Germany)

    2015-10-15

    The aim of the study was to investigate DNA double strand break (DSB) formation and its correlation with the absorbed dose to the blood lymphocytes of patients undergoing their first peptide receptor radionuclide therapy (PRRT) with {sup 177}Lu-labelled DOTATATE/DOTATOC. The study group comprised 16 patients receiving their first PRRT. At least six peripheral blood samples were obtained before, and between 0.5 h and 48 h after radionuclide administration. From the time-activity curves of the blood and the whole body, residence times for blood self-irradiation and whole-body irradiation were determined. Peripheral blood lymphocytes were isolated, fixed with ethanol and subjected to immunofluorescence staining for colocalizing γ-H2AX/53BP1 DSB-marking foci. The average number of DSB foci per cell per patient sample was determined as a function of the absorbed dose to the blood and compared with an in vitro calibration curve established in our laboratory with {sup 131}I and {sup 177}Lu. The average number of radiation-induced foci (RIF) per cell increased over the first 5 h after radionuclide administration and decreased thereafter. A linear fit from 0 to 5 h as a function of the absorbed dose to the blood agreed with our in vitro calibration curve. At later time-points the number of RIF decreased, indicating progression of DNA repair. Measurements of RIF and the absorbed dose to the blood after systemic administration of {sup 177}Lu may be used to obtain data on the individual dose-response relationships in vivo. Individual patient data were characterized by a linear dose-dependent increase and an exponential decay function describing repair. (orig.)

  6. DNA damage in blood lymphocytes in patients after 177Lu peptide receptor radionuclide therapy

    The aim of the study was to investigate DNA double strand break (DSB) formation and its correlation with the absorbed dose to the blood lymphocytes of patients undergoing their first peptide receptor radionuclide therapy (PRRT) with 177Lu-labelled DOTATATE/DOTATOC. The study group comprised 16 patients receiving their first PRRT. At least six peripheral blood samples were obtained before, and between 0.5 h and 48 h after radionuclide administration. From the time-activity curves of the blood and the whole body, residence times for blood self-irradiation and whole-body irradiation were determined. Peripheral blood lymphocytes were isolated, fixed with ethanol and subjected to immunofluorescence staining for colocalizing γ-H2AX/53BP1 DSB-marking foci. The average number of DSB foci per cell per patient sample was determined as a function of the absorbed dose to the blood and compared with an in vitro calibration curve established in our laboratory with 131I and 177Lu. The average number of radiation-induced foci (RIF) per cell increased over the first 5 h after radionuclide administration and decreased thereafter. A linear fit from 0 to 5 h as a function of the absorbed dose to the blood agreed with our in vitro calibration curve. At later time-points the number of RIF decreased, indicating progression of DNA repair. Measurements of RIF and the absorbed dose to the blood after systemic administration of 177Lu may be used to obtain data on the individual dose-response relationships in vivo. Individual patient data were characterized by a linear dose-dependent increase and an exponential decay function describing repair. (orig.)

  7. Biological effective doses in 300 patients undergoing therapy with 177Lu-octreotate

    Full text of publication follows. Aim: fractionated therapy with 177Lu-octreotate has been reported to be an effective treatment option for patients with generalized neuroendocrine tumors. The main aim of this study was to calculate the biological effective dose (BED) to the kidneys using an individualized dosimetry protocol, and to assess differences in the number of possible treatment cycles based on BED compared to those based on absorbed dose. Methods: a total of 148 female and 152 male patients with neuroendocrine tumors with high somatostatin receptor expression (grade 3 or 4) were included. After infusion of 7.4 GBq of 177Lu-octreotate SPECT/CT images over the abdomen were acquired at 24, 96 and 168 h after infusion. Absorbed dose to kidneys was calculated based on pharmacokinetic data obtained from SPECT/CT. From this the effective half-life of 177Lu-octreotate in the kidneys was estimated, and BED was calculated using the equation described by Barone et al. (1). Results and discussion: for a single treatment cycle of 7.4 GBq, median (1:st-3:rd quartiles) BED was 5.0 Gy (3.9-6.1) in the right kidney and 4.7 Gy (3.7-5.8) in the left kidney. For the same treatment cycle, BED was 9.0% (7.1-11.3) and 8.7% (7.0-10.9) higher than absorbed dose in right and left kidneys, respectively. In patients with high absorbed doses, BED could be more than 20% higher than absorbed dose. Assuming an absorbed dose limit of 23 Gy and a BED limit of 45 Gy to the kidneys, the possible number of treatment cycles was 5.4 (4.5-6.8) based on absorbed dose while using BED increased the number of possible cycles to 9.8 (8.1-12.5). Conclusions: although biological effective dose to the kidneys is higher than absorbed dose, use of BED to estimate the number of possible treatment cycles in 177Lu-octreotate therapy may allow for more treatment cycles than the use of absorbed dose. Refs: 1) Barone, R. et al. Patient-specific dosimetry in predicting renal toxicity with (90)Y

  8. {sup 177}Lu-DOTMP: a viable agent for palliative radiotherapy of painful bone metastasis

    Das, T.; Chakraborty, S.; Banerjee, S. [Radiopharmaceuticals Div., Bhabha Atomic Research Centre, Mumbai (India); Sarma, H.D. [Radiation Biology and Health Sciences Div., Bhabha Atomic Research Centre, Mumbai (India)

    2008-07-01

    The suitable nuclear decay characteristics [T{sub 1/2} = 6.73 d, E{sub {beta}}{sub (max)} = 497 keV, E{sub {gamma}} = 113 keV (6.4%), 208 keV (11%)] as well as the feasibility of large-scale production with adequate specific activity and radionuclidic purity using a moderate flux reactor are important attributes towards {sup 177}Lu to be considered as a promising radionuclide for palliative care in painful bone metastasis. The present study describes the preparation of {sup 177}Lu complex of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene phosphonic acid (DOTMP) and its preliminary biological evaluation in animal models with an aim to proposing it as a viable radiopharmaceutical for bone pain palliation. The choice DOTMP as the polyaminophosphonic acid carrier ligand is based on the enhanced thermodynamic stability and kinetic inertness of the metal-ligand complexes with macrocyclic chelators. {sup 177}Lu was produced with a specific activity of {proportional_to} 12 GBq/mg ({proportional_to} 324 mCi/mg) and radionuclidic purity of 99.98% by irradiation of natural Lu{sub 2}O{sub 3} target at a thermal neutron flux of {proportional_to} 6 x 10{sup 13} n/cm{sup 2} s for 21 d. {sup 177}Lu-DOTMP complex was prepared in high yield and excellent radiochemical purity (> 99%) using DOTMP synthesized and characterized in-house. The complex exhibited excellent in-vitro stability at room temperature. Biodistribution studies in Wistar rats showed rapid skeletal accumulation of the injected activity [(1.60{+-}0.19)% per gram in femur at 3 h post-injection] with fast clearance from blood and minimal uptake in any of the major organs. Scintigraphic studies carried out in normal Wistar rats and New Zealand white rabbits also demonstrated significant accumulation of the agent in skeleton and almost no retention in any other vital organs. (orig.)

  9. Preparation and quality control of 177Lu-DOTA-anti-CD20 for Radio immunotherapy

    Hassan Yousefnia; Amir Reza Jalilian; Samaneh Zolghadri; Simindokht Shirvani-Arani; Ali Bahrami-Samani; Mohammad Ghannadi-Maragheh

    2010-01-01

    Introduction: The importance of existence and application of radiolabeled anti-CD20 monoclonal antibodies at nonmyeloablative doses in treating B-cell NHL is well recognized throughout the world. In this work, Rituximab was successively labeled with 177Lu-lutetium chloride. Methods: Lu-177 chloride was obtained by thermal neutron flux (4 × 1013 n.cm-2.s-1) of natural Lu2O3 sample with a specific activity of 2.6-3 GBq/mg. The macrocyclic bifunctional chelating agent, N-succinimidyl-1...

  10. Experimental study of the biological properties of 188Re-Hepama-1 biologic superparamagnetic nanoparticles

    Objective: To investigate a new biologic-superparamagnetic nanoparticles's characteristics of immunological activity, biological distributing in vivo, targeting and inhibiting tumor effect. Methods: The experimental group 188Re-Hepama-l-superparamagnetic nanoparticles, and control groups, including 188ReO4-, 188Re-Hepama-1, and 188Re-superparamagnetic nanoparticles, were set up. The distributions were measured after injection 4 h and 24 h by caudal vein of Kuming mice. The magnetic targeting experiments in vivo were clone with and without magnetic field in liver after injection in New Zealand rabbit. The inhibiting tumor effect on hepatic cancer cell lines SMMC-7721 of the above four 188Re labeled products were measured by mono nuclear cell direct cytotoxicity assay method. Results: After injection 4 h and 24 h by vein, the liver taking was highest in group 188Re-Hepama-l-superparamagnetic nanoparticles. The radiative activity in liver in magnetism zoo was higher than in non magnetism zoo in 188Re- Hepama-1-superparamagnetic nanoparticles after applying magnetic field in left lobe of liver, and the ratio of in magnetism zoo to non magnetism zoo was 1.87. And the half effective inhibition radioactive concentrations (IC50) in 188Re-Hepama-l-superparamagnetic nanoparticles was one forth of 188ReO4-. Conclusion: 188Re- Hepama-l-superparamagnetic nanoparticles showed its fine stability in intro, good immunological activity and significant liver target. (authors)

  11. Peptide labeling using 188Re, 188Re-MAG3 and 153Sm-H1ETA. A comparison on their in vitro lipophilicity

    Lanreotide peptide was labeled with 153Sm-H1ETA and 188Re-MAG3 in order to evaluate whether or not their conjugation to the peptide produce significant differences of the in vitro lipophilicity with respect to the 188Re-lanreotide prepared by the direct labeling method (highly lipophilic). The differences of lipophilicity between the complexes, were evaluated using a reverse phase HPLC system. The measured lipophilicity of 153Sm-H1ETA-lanreotide, 188Re-MAG3-lanreotide and 188Re-lanreotide was taken to be the capacity factor [k' = (tR - t0)/t0 where tR is the retention time and t0 is the dead time] for each of the complexes under identical chromatography conditions. Results showed that the in vitro lipophilicity decreased in the order 188Re-lanreotide (direct labeling), 188Re-MAG3-lanreotide and 153Sm-H1ETA-lanreotide. Since the last one has a capacity factor (k') similar to that of 188Re-MAG3, some renal elimination for 153Sm-H1ETA-lanreotide could be expected, which probably would reduce the unnecessary radiation dose to normal tissues. (author)

  12. Is 161Tb and alternative to 177Lu? In vitro and in vivo comparison using DOTA-Folate conjugates

    Full text of publication follows. Background: The radio-lanthanide 161Tb decays with a half-life of 165.4 h by emission of low energy β- particles and Auger-e- for therapeutic purposes and γ-radiation suitable for SPECT. 161Tb was recently proposed as a potential alternative to 177Lu for targeted radionuclide tumor therapy [Refs.1,2]. The goal of this study was to compare 161Tb and 177Lu using a tumor targeted DOTA-folate conjugate (cm09 [Ref.3]). Methods. 161Tb was produced by a previously published procedure at PSI [Refs.2,3]. 177Lu was obtained from ITG GmbH, Munich, Germany). Radiolabeling of cm09 was carried out by incubation of the reaction mixture at 95 C. degrees for 10 min. In vitro the effects of 161Tb-cm09 and 177Lu-cm09 were tested on folate receptor (FR)-positive KB cells using an MTT viability assay. In vivo the therapeutic effects of 161Tb-cm09 and 177Lu-cm09 (10 MBq, 0.5 nmol) were compared over 7 weeks in KB tumor bearing mice. Results: 161TbCl3 was prepared in an excellent quality and at high radioactivity concentration. Both, 161Tb-cm09 and 177Lu-cm09 were obtained at high purity (> 98%) at a specific activity of > 40 MBq/nmol. In KB tumor cells, 161Tb-cm09 reduced cell viability more effectively than 177Lu-cm09 (161Tb-cm09: IC50 ∼ 0.014 MBq/ml versus 177Lu-cm09: IC50: ∼ 0.063 MBq/ml). In vivo 161Tb-cm09 showed an increased therapeutic efficacy to reduce tumor growth compared to 177Lu-cm09 which was in agreement with an increased absorbed tumor dose (3.3 Gy/MBq for 161Tb-cm09 versus 2.4 Gy/MBq for 177Lu-cm09). Hence an increased average survival time was observed for mice treated with 161Tb-cm09 (54 d) compared to 177Lu-cm09 (35 d). Conclusions. In this study we demonstrated increased therapeutic efficacy of 161Tb-cm09 compared to 177Lu-cm09 to reduce tumor cell growth in vitro and in vivo. Further investigations with other tumor targeting agents will be necessary to draw final conclusions about the future clinical perspectives of 161Tb

  13. Comparative Efficacy of 177Lu and 90Y for Anti-CD20 Pretargeted Radioimmunotherapy in Murine Lymphoma Xenograft Models

    Frost, Sophia; Frayo, Shani; Miller, Brian W.; Orozco, Johnnie J.; Booth, Garrett C.; Hylarides, Mark; Lin, Yukang; Green, Damian J.; Gopal, Ajay K.; Pagel, John M.; Back, Tom; Fisher, Darrell R.; Press, Oliver W.

    2015-03-01

    Pretargeted radioimmunotherapy (PRIT) is a multi-step method of selectively delivering high doses of radiotherapy to tumor cells while minimizing exposure to surrounding tissues. Yttrium-90 (90Y) and lutetium-177 (177Lu) are two of the most promising beta-particle emitting radionuclides used for radioimmunotherapy, which despite having similar chemistries differ distinctly in terms of radiophysical features. These differences may have important consequences for the absorbed dose to tumors and normal organs. Whereas 90Y has been successfully applied in a number of preclinical and clinical radioimmunotherapy settings, there have been few published pretargeting studies with 177Lu. We therefore compared the therapeutic potential of targeting either 90Y or 177Lu to human B-cell lymphoma xenografts in mice.

  14. Application of single-vial ready-for-use formulation of 111In- or 177Lu-labelled somatostatin analogs

    For the sake of safety it would be desirable to store and transport the ready-for-use liquid formulation (diagnostics and therapeutics) of radiolabelled peptides. The use of ethanol, in combination with a mixture of gentisic- and ascorbic acid, has superior effects on stabilizing radiolabelled somatostatin analogs. As a consequence, 111In- and 177Lu-labelled somatostatin analogs can be stored and transported in a single-vial ready-for-use liquid formulation up to 7 days after radiolabelling. - Highlights: • Optimal quencher combination: ascorbic- and gentisic acid and ethanol. • Used quencher concentrations had no effect on pharmacokinetics. • Purging the reaction mixture with N2 after radiolabelling resulted in 10% higher RCP. • Quencher mixture stabilize 111In- and 177Lu-labelled SS-analogs during 7 days. • Enables to store and transport 111In- and 177Lu-labelled SS-analogs in a single-vial

  15. Uncertainty propagation for SPECT/CT-based renal dosimetry in 177Lu peptide receptor radionuclide therapy

    Gustafsson, Johan; Brolin, Gustav; Cox, Maurice; Ljungberg, Michael; Johansson, Lena; Sjögreen Gleisner, Katarina

    2015-11-01

    A computer model of a patient-specific clinical 177Lu-DOTATATE therapy dosimetry system is constructed and used for investigating the variability of renal absorbed dose and biologically effective dose (BED) estimates. As patient models, three anthropomorphic computer phantoms coupled to a pharmacokinetic model of 177Lu-DOTATATE are used. Aspects included in the dosimetry-process model are the gamma-camera calibration via measurement of the system sensitivity, selection of imaging time points, generation of mass-density maps from CT, SPECT imaging, volume-of-interest delineation, calculation of absorbed-dose rate via a combination of local energy deposition for electrons and Monte Carlo simulations of photons, curve fitting and integration to absorbed dose and BED. By introducing variabilities in these steps the combined uncertainty in the output quantity is determined. The importance of different sources of uncertainty is assessed by observing the decrease in standard deviation when removing a particular source. The obtained absorbed dose and BED standard deviations are approximately 6% and slightly higher if considering the root mean square error. The most important sources of variability are the compensation for partial volume effects via a recovery coefficient and the gamma-camera calibration via the system sensitivity.

  16. Uncertainty propagation for SPECT/CT-based renal dosimetry in (177)Lu peptide receptor radionuclide therapy.

    Gustafsson, Johan; Brolin, Gustav; Cox, Maurice; Ljungberg, Michael; Johansson, Lena; Gleisner, Katarina Sjögreen

    2015-11-01

    A computer model of a patient-specific clinical (177)Lu-DOTATATE therapy dosimetry system is constructed and used for investigating the variability of renal absorbed dose and biologically effective dose (BED) estimates. As patient models, three anthropomorphic computer phantoms coupled to a pharmacokinetic model of (177)Lu-DOTATATE are used. Aspects included in the dosimetry-process model are the gamma-camera calibration via measurement of the system sensitivity, selection of imaging time points, generation of mass-density maps from CT, SPECT imaging, volume-of-interest delineation, calculation of absorbed-dose rate via a combination of local energy deposition for electrons and Monte Carlo simulations of photons, curve fitting and integration to absorbed dose and BED. By introducing variabilities in these steps the combined uncertainty in the output quantity is determined. The importance of different sources of uncertainty is assessed by observing the decrease in standard deviation when removing a particular source. The obtained absorbed dose and BED standard deviations are approximately 6% and slightly higher if considering the root mean square error. The most important sources of variability are the compensation for partial volume effects via a recovery coefficient and the gamma-camera calibration via the system sensitivity. PMID:26458139

  17. Reducing Renal Uptake of {sup 177}Lu Labeled CCK Derivative using Basic Amino Acids

    Lee, Soyoung; Lim, Jaecheong; Joh, Eunha [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    Radiolabeled peptides have been designed to target the relative receptors overespressed in tumor cells, such as integrin αvβ3, gastrin-releasing peptide receptor (GRPR), melanocortin-1 receptor (MC1-R), glucagon-like peptide-a receptor (GLP-1R), and cholecystokinin (CCK) receptor. Most of these peptides are eliminated from the body via the kidney and are partly reabsorbed in the proximal tubular cells. However, the high renal uptake of the radiolabeled peptides may lead to renal toxicity. In this study we investigated various amino acid solutions to reduce the renal uptake of {sup 177}Lu-DOTA-CCK derivative. Renal uptake of {sup 177}Lu-DOTA-CCK derivative is effectively reduced by the administration of positively charged amino acids. The administration of 12 mg of L-lysine was as effective in reducing the renal uptake as 6 mg of lysine and 6 mg of arginine combinations. Further studies will be performed to identify the most potent inhibitor of renal reuptake of radiolabeled peptides and minimize the chance of unwanted side effects.

  18. Reducing Renal Uptake of 177Lu Labeled CCK Derivative using Basic Amino Acids

    Radiolabeled peptides have been designed to target the relative receptors overespressed in tumor cells, such as integrin αvβ3, gastrin-releasing peptide receptor (GRPR), melanocortin-1 receptor (MC1-R), glucagon-like peptide-a receptor (GLP-1R), and cholecystokinin (CCK) receptor. Most of these peptides are eliminated from the body via the kidney and are partly reabsorbed in the proximal tubular cells. However, the high renal uptake of the radiolabeled peptides may lead to renal toxicity. In this study we investigated various amino acid solutions to reduce the renal uptake of 177Lu-DOTA-CCK derivative. Renal uptake of 177Lu-DOTA-CCK derivative is effectively reduced by the administration of positively charged amino acids. The administration of 12 mg of L-lysine was as effective in reducing the renal uptake as 6 mg of lysine and 6 mg of arginine combinations. Further studies will be performed to identify the most potent inhibitor of renal reuptake of radiolabeled peptides and minimize the chance of unwanted side effects

  19. Targeted radiotherapy with 177 Lu-DOTA-TATE in athymic mice with induced pancreatic malignant tumours

    Malignant pancreas tumours induced in athymic mice are a good model for targeted radiotherapy. The objective of this research was to estimate pancreatic tumour absorbed radiation doses and to evaluate 177Lu-DOTA-TATE as a therapeutic radiopharmaceutical that could be used in humans. AR42J murine pancreas cancer cells, which over-express somatostatin receptors, were injected in athymic mice and 20 days later the mean tumour size was 3.08 square cm (n=3). A mean of 86.3 MBq 177Lu-DOTA-TATE, was injected in a tail vein and 19 days after therapy the size of the tumours was 0.81 square cm. There was a partial relapse and after 16 days, when sacrificed, the mean tumour size was 8.28 cubic cm. An epithelial and sarcoma mixed tumour in the kidney of one treated mouse was found. The tumour of the control mouse was 8.61 cubic cm when sacrificed 14 days after tumour induction. Radiotherapy estimates to the tumours was 35.9-39.7 Gy and the tumours might have been completely reduced with a second therapy dose. These preliminary studies justify further therapeutic and dosimetry estimations to ensure that Lu-177-DOTA-TATE will act as expected in man, considering kidney radiation. (Author)

  20. Amifostine protects rat kidneys during peptide receptor radionuclide therapy with [177Lu-DOTA0,Tyr3]octreotate

    In peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues, the kidneys are the major dose-limiting organs, because of tubular reabsorption and retention of radioactivity. Preventing renal uptake or toxicity will allow for higher tumour radiation doses. We tested the cytoprotective drug amifostine, which selectively protects healthy tissue during chemo- and radiotherapy, for its renoprotective capacities after PRRT with high-dose [177Lu-DOTA0,Tyr3]octreotate. Male Lewis rats were injected with 278 or 555 MBq [177Lu-DOTA0,Tyr3]octreotate to create renal damage and were followed up for 130 days. For renoprotection, rats received either amifostine or co-injection with lysine. Kidneys, blood and urine were collected for toxicity measurements. At 130 days after PRRT, a single-photon emission computed tomography (SPECT) scan was performed to quantify tubular uptake of 99mTc-dimercaptosuccinic acid (DMSA), a measure of tubular function. Treatment with 555 MBq [177Lu-DOTA0,Tyr3]octreotate resulted in body weight loss, elevated creatinine and proteinuria. Amifostine and lysine treatment significantly prevented this rise in creatinine and the level of proteinuria, but did not improve the histological damage. In contrast, after 278 MBq [177Lu-DOTA0,Tyr3]octreotate, creatinine values were slightly, but not significantly, elevated compared with the control rats. Proteinuria and histological damage were different from controls and were significantly improved by amifostine treatment. Quantification of 99mTc-DMSA SPECT scintigrams at 130 days after [177Lu-DOTA0,Tyr3]octreotate therapy correlated well with 1/creatinine (r 2 = 0.772, p 177Lu-DOTA0,Tyr3]octreotate. Besides lysine, amifostine might be used in clinical PRRT as well as to maximise anti-tumour efficacy. (orig.)

  1. Preparation and preliminary studies on 177Lu-labeled hydroxyapatite particles for possible use in the therapy of liver cancer

    Introduction: Intra-arterial administration of particulates labeled with suitable β--emitting radionuclides has emerged as one of the most successful modality for the treatment of primary and metastatic liver cancer. 177Lu [T1/2=6.73 d, Eβ(max)=0.49 MeV, Eγ=208 keV (11%)] could be envisaged as a viable radionuclide for use in liver cancer therapy with wider acceptability owing to its feasibility of production in large-scale and relatively longer half-life providing logistic advantages. Hydroxyapatite (HA) particles of 20-60 μm size range are chosen as the particulate carrier due to its excellent biocompatibility and ease of labeling with lanthanides. Methods: 177Lu was produced by thermal neutron bombardment on enriched Lu target. HA particles of desired size range were synthesized and characterized. Radiolabeling of HA particles was achieved at room temperatures within 30 min. The biological behavior of 177Lu-labeled HA particles prepared under optimized conditions was tested in Wistar rats. Results: 177Lu was produced with a specific activity of 444.2±41.8 GBq/mg and radionuclidic purity of 99.98%. 177Lu-HA was prepared with high radiochemical purity of >99%, and the radiolabeled agent showed excellent in vitro stability. The agent exhibited ∼73% retention of injected activity in liver after 14 days postadministration with insignificant uptake in any other major organ/tissue except skeleton in biodistribution and imaging studies. Conclusion: 177Lu-HA exhibited promising features in radiochemical studies. However, preliminary biodistribution studies in normal Wistar rats exhibited suboptimum liver retention and an undesirable skeletal uptake

  2. Preparation of 188W/188Re generator in a clinical-scale

    A 188W/188Re generator based on acid-treated alumina is prepared for medical application. 188Re can be eluted into vacuum vial with 0.9% NaCl solution in the presence or absence of ascorbic acid. The elution yield of 188Re is more than 70% during a period of three months. The 188W leakage is less than 10 - 4 %. Both the radiochemical purity and radionuclide purity are more than 99%

  3. Direct in vitro and in vivo comparison of 161Tb and 177Lu using a tumour-targeting folate conjugate

    The radiolanthanide 161Tb (T1/2 = 6.90 days, Eβ-av = 154 keV) was recently proposed as a potential alternative to 177Lu (T1/2 = 6.71 days, Eβ-av = 134 keV) due to similar physical decay characteristics but additional conversion and Auger electrons that may enhance the therapeutic efficacy. The goal of this study was to compare 161Tb and 177Lu in vitro and in vivo using a tumour-targeted DOTA-folate conjugate (cm09). 161Tb-cm09 and 177Lu-cm09 were tested in vitro on folate receptor (FR)-positive KB and IGROV-1 cancer cells using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) viability assay. In vivo 161Tb-cm09 and 177Lu-cm09 (10 MBq, 0.5 nmol) were investigated in two different tumour mouse models with regard to the biodistribution, the possibility for single photon emission computed tomography (SPECT) imaging and the antitumour efficacy. Potentially undesired side effects were monitored over 6 months by determination of plasma parameters and examination of kidney function with quantitative SPECT using 99mTc-dimercaptosuccinic acid (DMSA). To obtain half-maximal inhibition of tumour cell viability a 4.5-fold (KB) and 1.7-fold (IGROV-1) lower radioactivity concentration was required for 161Tb-cm09 (IC50 ∝0.014 MBq/ml and ∝2.53 MBq/ml) compared to 177Lu-cm09 (IC50 ∝0.063 MBq/ml and ∝4.52 MBq/ml). SPECT imaging visualized tumours of mice with both radioconjugates. However, in therapy studies 161Tb-cm09 reduced tumour growth more efficiently than 177Lu-cm09. These findings were in line with the higher absorbed tumour dose for 161Tb-cm09 (3.3 Gy/MBq) compared to 177Lu-cm09 (2.4 Gy/MBq). None of the monitored parameters indicated signs of impaired kidney function over the whole time period of investigation after injection of the radiofolates. Compared to 177Lu-cm09 we demonstrated equal imaging features for 161Tb-cm09 but an increased therapeutic efficacy for 161Tb-cm09 in both tumour cell lines in vitro and in vivo. Further preclinical

  4. Multispecies animal investigation on biodistribution, pharmacokinetics and toxicity of {sup 177}Lu-EDTMP, a potential bone pain palliation agent

    Mathe, Domokos [Department of Applied Radioisotopes and Animal Experimentation, National ' Frederic Joliot-Curie' Institute of Radiobiology and Radiohygiene, H-1221 Budapest (Hungary)], E-mail: mdomokos@hp.osski.hu; Balogh, Lajos; Polyak, Andras; Kiraly, Reka [Department of Applied Radioisotopes and Animal Experimentation, National ' Frederic Joliot-Curie' Institute of Radiobiology and Radiohygiene, H-1221 Budapest (Hungary); Marian, Terez [Institute of Nuclear Medicine, Debrecen University, Debrecen (Hungary); Pawlak, Dariusz [Institute of Atomic Energy, Radioisotope Centre POLATOM, Swierk-Otwock (Poland); Zaknun, John J.; Pillai, Maroor R.A. [International Atomic Energy Agency (IAEA), Vienna (Austria); Janoki, Gyozo A. [Department of Applied Radioisotopes and Animal Experimentation, National ' Frederic Joliot-Curie' Institute of Radiobiology and Radiohygiene, H-1221 Budapest (Hungary)

    2010-02-15

    Introduction: Radionuclide therapy (RNT) is an effective method for bone pain palliation in patients suffering from bone metastasis. Due to the long half-life, easy production and relatively low {beta}- energy, {sup 177}Lu [T{sub 1/2}=6.73 days, E{sub {beta}}{sub max}=497 keV, E{sub {gamma}}=113 keV (6.4%), 208 keV (11%)]-based radiopharmaceuticals offer logistical advantage for wider use. This paper reports the results of a multispecies biodistribution and toxicity studies of {sup 177}Lu-EDTMP to collect preclinical data for starting human clinical trials. Methods: {sup 177}Lu-EDTMP with radiochemical purity greater than 99% was formulated by using a lyophilized kit of EDTMP (35 mg of EDTMP, 5.72 g of CaO and 14.1 mg of NaOH). Biodistribution studies were conducted in mice and rabbits. Small animal imaging was performed using NanoSPECT/CT (Mediso, Ltd., Hungary) and digital autoradiography. Gamma camera imaging was done in rabbits and dogs. Four levels of activity (9.25 through 37 MBq/kg body weight) of {sup 177}Lu-EDTMP were injected in four groups of three dogs each to study the toxicological effects. Results: {sup 177}Lu-EDTMP accumulated almost exclusively in the skeletal system (peak ca. 41% of the injected activity in bone with terminal elimination half-life of 2130 and 1870 h in mice and rabbits, respectively) with a peak uptake during 1-3 h. Excretion of the radiopharmaceutical was through the urinary system. Imaging studies showed that all species (mouse, rat, rabbit and dog) take up the compound in regions of remodeling bone, while kidney retention is not visible after 1 day postinjection (pi). In dogs, the highest applied activity (37 MBq/kg body weight) led to a moderate decrease in platelet concentration (mean, 160 g/L) at 1 week pi with no toxicity. Conclusion: The protracted effective half-life of {sup 177}Lu-EDTMP in bone supports that modifying the EDTMP molecule by introducing {sup 177}Lu does not alter its biological behaviour as a specific bone

  5. Synthesis and primary biological evaluation of 188ReN-NEMPTDD

    A new nitrido-188Re complex, 188ReN-NEMPTDD, was synthesized through a modified method in high yield. This complex was stable in vitro. The biodistribution in normal mice showed that this ReN complex accumulated in the liver and was eliminated quickly from almost all organs. VX2 carcinoma was grown in the livers of rabbits. Transcatheter arterial embolization (TAE) was performed using 188ReN-NEMPTDD/lipiodol solution. The SPECT images showed that the lipiodol solution could be concentrated in the tumor for about 12 hours. These results indicated that 188ReN-NEMPTDD/lipiodol could be a potential radiopharmaceutical for liver cancer. (author)

  6. An alternative approach to the preparation of 188Re radiopharmaceuticals from generator-produced [188ReO4]-: efficient synthesis of 188Re(V)-meso-2,3-dimercaptosuccinic acid

    A new efficient approach for the preparation of 188Re radiopharmaceuticals starting from [188ReO4]-, produced at a carrier-free level through the 188W/188Re generator system, is described. The reaction procedure was based on the combined action of different reagents and has been applied in detail to the preparation of the therapeutic agent 188Re(V)-DMSA (H2DMSA [meso-2,3-dimercaptosuccinic acid]). The most efficient combination required the use of SnCl2, oxalate ions, and γ-cyclodextrin. These were reacted with [188ReO4]- and H2DMSA to afford the final radiopharmaceutical in high radiochemical purity, at room temperature, and in weakly acidic solution. The role played by the various reagents in the reaction was investigated. It was found that SnCl2 behaved as the actual reducing agent, whereas oxalate and γ-cyclodextrin greatly enhanced the ease of reduction of [188ReO4]- through the action of two hypothetical mechanisms. In the first step of the reaction, oxalate ions gave rise to the formation of Re(VII) complexes with the concomitant expansion of the coordination sphere of the metal. This process strongly favored the electron transfer between Sn2+ and Re+7 centers, giving rise to intermediate reduced rhenium complexes. These species were further stabilized by the formation of transient host-guest aggregates with γ-cyclodextrin and finally converted into 188Re(V)-DMSA through simple replacement of the coordinated ligands by H2DMSA

  7. Exploitation of nano alumina for the chromatographic separation of clinical grade 188Re from 188W: a renaissance of the 188W/188Re generator technology.

    Chakravarty, Rubel; Shukla, Rakesh; Ram, Ramu; Venkatesh, Meera; Tyagi, Avesh Kumar; Dash, Ashutosh

    2011-08-15

    The (188)W/(188)Re generator using an acidic alumina column for chromatographic separation of (188)Re has remained the most popular procedure world over. The capacity of bulk alumina for taking up tungstate ions is limited (∼50 mg W/g) necessitating the use of very high specific activity (188)W (185-370 GBq/g), which can be produced only in very few high flux reactors available in the world. In this context, the use of high-capacity sorbents would not only mitigate the requirement of high specific activity (188)W but also facilitate easy access to (188)Re. A solid state mechanochemical approach to synthesize nanocrystalline γ-Al(2)O(3) possessing very high W-sorption capacity (500 mg W/g) was developed. The structural and other investigations of the material were carried out using X-ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer Emmett Teller (BET) surface area analysis, thermogravimetric-differential thermal analysis (TG-DTA), and dynamic light scattering (DLS) techniques. The synthesized material had an average crystallite size of ∼5 nm and surface area of 252 ± 10 m(2)/g. Sorption characteristics such as distribution ratios (K(d)), capacity, breakthrough profile, and elution behavior were investigated to ensure quantitative uptake of (188)W and selective elution of (188)Re. A 11.1 GBq (300 mCi) (188)W/(188)Re generator was developed using nanocrystalline γ-Al(2)O(3), and its performance was evaluated for a period of 6 months. The overall yield of (188)Re was >80%, with >99.999% radionuclidic purity and >99% radiochemical purity. The eluted (188)Re possessed appreciably high radioactive concentration and was compatible for the preparation of (188)Re labeled radiopharmaceuticals. PMID:21726091

  8. Labeling Lanreotide with 125I and 188Re. China

    Lanreotide (D-β-Nal-Cys-Try-D-Trp-Lys-Val-Cys-Thr-NH2) is a new somatostatin analogue. It can bind to human somatostatin receptor (hSSTR) subtype 2 through 5 with high affinity and to hSSTR subtype 1 with low affinity. We investigate labeling condition, quality control and stability in vitro of 125I-Lanreotide and 188Re-lanreotide respectively. (A) Lanreotide is labeled with 125I using Chloramine T. The effect of reaction condition (such as reaction time, pH value, Lanreotide amount, quantity of Chloramine T and reaction volume) on labeling yield is investigated in detail. (B) The labeling yield and radiochemical purity (RP) is measured with paper chromatography (PC) and Sep-Pak C18 Cartridge. For PC method, 125I-Lanreotide is spotted on the Whatman No.1 paper and developed in the mixture of CH3CH2CH2CH2OH and CH3CH2OH and NH4OH (v/v/v=5:2:1), the Rf value of every component in the mobile phase is given in table 1. For Sep-Pak C18 Cartridge methods each cartridge is washed with 10 ml of ethanol followed by 10 ml of iso-CH3CH2CH2OH solution. Aliquots of 0.1 mI sample is loaded onto the cartridge, unbound peptide (sodium iodine-125) is eluted with 5 ml of 0.5mol/L sodium acetate solution, 125I-Lanreotide is eluted with 5 mI of 95% aqueous ethanol solution. (C) The stability of 125I-Lanreotide in vitro is investigated by labeling compound incubating for 48 hours at 37 deg. C in the 0.9% sodium chloride solution and RP is tested by PC at specific time intervals. (D) Lanreotide is labeled directly with 188Re via the mixture of citrate and tartate using stannous chloride as reduced agent. The influence of reaction conditions such as pH, temperature, amount of stannous chloride, amount of Lanreotide and reaction time on labeling yield is investigated in detail. At the time, the stability in vitro quality control and animal test are evaluated

  9. Hypocalcaemia after treatment with [177Lu-DOTA0,Tyr3]octreotate

    The aim of this study was to explore the possible mechanisms involved in an observed decline in serum calcium levels in patients with a neuroendocrine tumour (NET) treated with [177Lu-DOTA0,Tyr3]octreotate (177Lu-octreotate). In 47 patients with NET who were normocalcaemic at baseline, serum calcium, albumin, creatinine, alkaline phosphatase, gamma glutamyl transpeptidase, magnesium, phosphate and 25-hydroxyvitamin D were prospectively analysed at baseline and up to 6 months after treatment. Parathyroid hormone (PTH), 1,25-dihydroxyvitamin D3, type 1 aminoterminal propeptide of procollagen, bone-specific alkaline phosphatase, carboxyterminal crosslinking telopeptide of bone collagen, collagen type I crosslinked N-telopeptide, and creatinine and calcium in 24-h urine samples, were evaluated at baseline and at 3 and 6 months. Another 153 patients with NET were included in a retrospective study to estimate the occurrence of hypocalcaemia in a larger patient group. In the prospectively included patients, the mean serum calcium level decreased significantly after treatment (2.31 ± 0.01 to 2.26 ± 0.02 mmol/l, p = 0.02). Eight patients (17 %) showed a marked decrease in serum calcium levels with a nadir of ≤2.10 mmol/l. In five patients (11 %), calcium substitution therapy was prescribed. PTH increased significantly (5.9 ± 0.6 to 6.7 ± 0.8 pmol/l, p = 0.02), presumably in response to the decreasing serum calcium levels. 25-Hydroxyvitamin D remained stable after treatment. Creatinine levels increased significantly (73 ± 3 to 77 ± 3 μmol/l, p = 0.01), but not enough to explain the hypocalcaemia. Phosphate levels remained unaffected. In the retrospectively analysed patients, the mean serum calcium level decreased significantly from 2.33 ± 0.01 at baseline to a nadir of 2.24 ± 0.01 mmol/l at 18 months after treatment (p 177Lu-octreotate, resulting in mild hypocalcaemia in about 20 % of patients. We excluded several potential causes of this hypocalcaemia, so the

  10. Hypocalcaemia after treatment with [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate

    Vliet, Esther I. van; Kam, Boen L.R.; Teunissen, Jaap J.M.; Krenning, Eric P.; Kwekkeboom, Dik J. [Erasmus MC, University Medical Center, Department of Nuclear Medicine, Rotterdam (Netherlands); Herder, Wouter W. de; Zillikens, M.C.; Peeters, Robin P. [Erasmus MC, University Medical Center, Department of Internal Medicine, Rotterdam (Netherlands); Rijke, Yolanda B. de [Erasmus MC, University Medical Center, Department of Clinical Chemistry, Rotterdam (Netherlands)

    2013-12-15

    The aim of this study was to explore the possible mechanisms involved in an observed decline in serum calcium levels in patients with a neuroendocrine tumour (NET) treated with [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate ({sup 177}Lu-octreotate). In 47 patients with NET who were normocalcaemic at baseline, serum calcium, albumin, creatinine, alkaline phosphatase, gamma glutamyl transpeptidase, magnesium, phosphate and 25-hydroxyvitamin D were prospectively analysed at baseline and up to 6 months after treatment. Parathyroid hormone (PTH), 1,25-dihydroxyvitamin D{sub 3}, type 1 aminoterminal propeptide of procollagen, bone-specific alkaline phosphatase, carboxyterminal crosslinking telopeptide of bone collagen, collagen type I crosslinked N-telopeptide, and creatinine and calcium in 24-h urine samples, were evaluated at baseline and at 3 and 6 months. Another 153 patients with NET were included in a retrospective study to estimate the occurrence of hypocalcaemia in a larger patient group. In the prospectively included patients, the mean serum calcium level decreased significantly after treatment (2.31 {+-} 0.01 to 2.26 {+-} 0.02 mmol/l, p = 0.02). Eight patients (17 %) showed a marked decrease in serum calcium levels with a nadir of {<=}2.10 mmol/l. In five patients (11 %), calcium substitution therapy was prescribed. PTH increased significantly (5.9 {+-} 0.6 to 6.7 {+-} 0.8 pmol/l, p = 0.02), presumably in response to the decreasing serum calcium levels. 25-Hydroxyvitamin D remained stable after treatment. Creatinine levels increased significantly (73 {+-} 3 to 77 {+-} 3 {mu}mol/l, p = 0.01), but not enough to explain the hypocalcaemia. Phosphate levels remained unaffected. In the retrospectively analysed patients, the mean serum calcium level decreased significantly from 2.33 {+-} 0.01 at baseline to a nadir of 2.24 {+-} 0.01 mmol/l at 18 months after treatment (p < 0.001). Of the 153 patients, 33 (22 %) showed a serum calcium nadir of {<=}2.10 mmol/l, and 11

  11. Evaluation of radiation safety in (177)Lu-PSMA therapy and development of outpatient treatment protocol.

    Demir, Mustafa; Abuqbeitah, Mohammad; Uslu-Beşli, Lebriz; Yıldırım, Özlem; Yeyin, Nami; Çavdar, İffet; Vatankulu, Betül; Gündüz, Hüseyin; Kabasakal, Levent

    2016-06-01

    The aim of this study is to investigate the outpatient treatment protocol and radiation safety of a new-emerging lutetium-177 ((177)Lu) prostate specific membrane antigen (PSMA) therapy. This work analyzed the dose rate of 23 patients treated with 7400 MBq (177)Lu-PSMA at different distances (0, 0.25, 0.50, 1.0 and 2.0 m) and variable time marks (0, 1, 2, 4, 18, 24, 48 and 120 h) after the termination of infusion. Blood samples were withdrawn from 17 patients within the same group at 3, 10, 20, 40, 60 and 90 min and 2, 3, 24 h after termination of infusion. Seven different patients were asked to collect urine for 24 h and a gamma well counter was used for counting samples. Family members were invited to wear an optically stimulated luminescence dosimeter whenever they were in the proximity of the patients up to 4-5 d. The total dose of the medical team including the radiopharmacist, physicist, physician, nurse, and nuclear medicine technologist was estimated by an electronic personnel dosimeter. The finger dose was determined using a ring thermoluminescent dosimeter for the radiopharmacist and nurse. The mean dose rate at 1 m after 4 h and 6 h was 23  ±  6 μSv h(-1) and 15  ±  4 μSv h(-1) respectively. The mean total dose to 23 caregivers was 202.3  ±  42.7 μSv (range: 120-265 μSv). The radiation dose of the nurse and radiopharmacist was 6 and 4 μSv per patient, respectively, whereas the dose of the physicist and physician was 2 μSv. The effective half life of blood distribution and early elimination was 0.4  ±  0.1 h and 5  ±  1 h, respectively. Seven patients excreted a mean of 45% (range: 32%-65%) from the initial activity in 6 h. Our findings demonstrate that (177)Lu-PSMA is a safe treatment modality to be applied as an outpatient protocol, since the dose rate decreases below the determined threshold of  <30 μSv h(-1) after approximately 5 h and degrades to 20 μSv h(-1) after 6

  12. A comparative study of {sup 188}Re(V)-meso-DMSA and {sup 188}Re(V)-rac-DMSA: preparation and in vivo evaluation in nude mice xenografted with a neuroendocrine tumor

    Park, Jun-Young [Department of Biomedical Laboratory Science, College of Health Science, Yonsei University, Wonju 220-710 (Korea, Republic of); Department of Nuclear Medicine, Yonsei University Health System, Seoul 120-752 (Korea, Republic of); Lee, Tae-Sup; Choi, Tae-Hyun; Cheon, Gi-Jeong; Choi, Chang-Woon [Laboratory of Nuclear Medicine, Korea Institute of Radiological and Medical Science, Seoul 139-706 (Korea, Republic of); Awh, Ok-Doo [Department of Nuclear Medicine, Yonsei University Health System, Seoul 120-752 (Korea, Republic of)], E-mail: immunoch@yonsei.ac.kr

    2007-11-15

    Dimercaptosuccinic acid (DMSA) exists in meso and racemic (rac) forms. Unlike a meso isomer, rac-2,3-DMSA is very soluble in water, strongly acidic solutions and organic solvents. Despite these differences, rac-2,3-DMSA has not been studied as a radiopharmaceutical. In this study, {sup 188}Re complexes with diastereomeric DMSA were prepared to compare the properties of {sup 188}Re(V)-rac-DMSA with those of {sup 188}Re(V)-meso-DMSA in in vitro and in vivo models. Methods: rac-2,3-DMSA was synthesized and radiolabeled with {sup 188}Re. The biodistribution and gamma camera imaging of {sup 188}Re(V)-meso-DMSA and {sup 188}Re(V)-rac-DMSA were performed in nude mice subcutaneously implanted with PC-12 cell lines. Results and conclusions: Both {sup 188}Re(V)-meso-DMSA and {sup 188}Re(V)-rac-DMSA showed excellent radiochemical purity and stability at room temperature. Compared with {sup 188}Re(V)-meso-DMSA, {sup 188}Re(V)-rac-DMSA needed a higher concentration of rac-DMSA and metabisulfite for maximum yields. {sup 188}Re(V)-meso-DMSA showed high labeling efficiency at pH 2, whereas {sup 188}Re(V)-rac-DMSA showed maximum yields at pH 5. The tumor uptake of {sup 188}Re(V)-rac-DMSA was 3.5 times higher than that of {sup 188}Re(V)-meso-DMSA at 1 h (P<.01). Gamma camera images showed that {sup 188}Re(V)-rac-DMSA was more selectively localized than {sup 188}Re(V)-meso-DMSA at the tumor region in a xenograft model. These results demonstrate that {sup 188}Re(V)-rac-DMSA may have better potential than {sup 188}Re(V)-meso-DMSA as a therapeutic agent against neuroendocrine tumors.

  13. A comparative study of 188Re(V)-meso-DMSA and 188Re(V)-rac-DMSA: preparation and in vivo evaluation in nude mice xenografted with a neuroendocrine tumor

    Dimercaptosuccinic acid (DMSA) exists in meso and racemic (rac) forms. Unlike a meso isomer, rac-2,3-DMSA is very soluble in water, strongly acidic solutions and organic solvents. Despite these differences, rac-2,3-DMSA has not been studied as a radiopharmaceutical. In this study, 188Re complexes with diastereomeric DMSA were prepared to compare the properties of 188Re(V)-rac-DMSA with those of 188Re(V)-meso-DMSA in in vitro and in vivo models. Methods: rac-2,3-DMSA was synthesized and radiolabeled with 188Re. The biodistribution and gamma camera imaging of 188Re(V)-meso-DMSA and 188Re(V)-rac-DMSA were performed in nude mice subcutaneously implanted with PC-12 cell lines. Results and conclusions: Both 188Re(V)-meso-DMSA and 188Re(V)-rac-DMSA showed excellent radiochemical purity and stability at room temperature. Compared with 188Re(V)-meso-DMSA, 188Re(V)-rac-DMSA needed a higher concentration of rac-DMSA and metabisulfite for maximum yields. 188Re(V)-meso-DMSA showed high labeling efficiency at pH 2, whereas 188Re(V)-rac-DMSA showed maximum yields at pH 5. The tumor uptake of 188Re(V)-rac-DMSA was 3.5 times higher than that of 188Re(V)-meso-DMSA at 1 h (P188Re(V)-rac-DMSA was more selectively localized than 188Re(V)-meso-DMSA at the tumor region in a xenograft model. These results demonstrate that 188Re(V)-rac-DMSA may have better potential than 188Re(V)-meso-DMSA as a therapeutic agent against neuroendocrine tumors

  14. Preclinical Evaluation of (177)Lu-Nimotuzumab: A Potential Tool for Radioimmunotherapy of Epidermal Growth Factor Receptor-Overexpressing Tumors

    Beckford, Denis R.; Eigner, Sebastian; Beran, Miloš; Eigner-Henke, Kateřina; Lázníček, M.; Melichar, František; Chinol, M.

    2011-01-01

    Roč. 26, č. 3 (2011), s. 287-297. ISSN 1084-9785 R&D Projects: GA MŠk OE08018 Institutional research plan: CEZ:AV0Z10480505 Keywords : EGFR * (177)Lu * monoclonal antibodies * Nimotuzumab Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 1.787, year: 2011

  15. IMPROVED PLANAR KIDNEY ACTIVITY CONCENTRATION ESTIMATE BY THE POSTERIOR VIEW METHOD IN 177LU-DOTATATE TREATMENTS.

    Magnander, Tobias; Svensson, Johanna; Båth, Magnus; Gjertsson, Peter; Bernhardt, Peter

    2016-06-01

    The aims of this study were to determine how different background regions of interest (ROIs) around the kidney represent true background activity in over- and underlying tissues in (177)Lu-DOTA-octreatate ((177)Lu-DOTATATE) treatments and to determine the influence of the background positions on the kidney activity concentration estimates by the conjugate view (ConjV) and posterior view (PostV) methods. The analysis was performed in single-photon emission computed tomography (SPECT) images of 20 patients, acquired 24 h post injection of a (177)Lu-DOTATATE treatment, by a computer algorithm that created planar images from the SPECT data. The ratio between the activity concentration in the background and the true background varied from 0.36 to 2.08 [coefficient of variation (CV) = 25-181 %] and from 0.44 to 1.52 (CV = 16-70 %) for the right and left kidneys, respectively. The activity concentration estimate in the kidneys was most accurate with the PostV method using a background ROI surrounding the whole kidney, and this combination might be an alternative planar method for improved kidney dosimetry in the (177)Lu-DOTATATE treatments. PMID:27012883

  16. 177Lu-DTPA-BIS-BIOTIN Binding of Octreotide-dextran-avidinated PANC-1 Cell Lines in Vitro

    Tyr3-octreotide, dextran-40 and avidin were used to prepare octreotide-dextran-avidin (TOC-Dx40-Av). DTPA-BIS-BIOTIN was labelled with 177Lu. The in vitro somatostatin receptor binding study was carried out by pretargeted method using TOC-Dx40-Av and 177Lu-DTPA-BIS-BIOTIN. The 24 well cell culture plates were prepared with PANC-1 cell monolayer and then incubated with TOC-Dx40-Av. After two washed with PBS, the cells were incubated with different concentration of 177Lu-DTPA-BIS-BIOTIN (48.8 ∼ 391 pmol). Cells uptake was evaluated with γ counter. The results showed that the chemical purity of TOC-Dx40-Av was over 99%. The results also showed that TOC-Dx40-Av remained high receptor binding affinity to somatostatin receptor which indicated that TOC- Dx40-Av could bind to 177Lu-DTPA-BIS-BIOTIN with the molar ratio of 1 : 1 on the cell surface. (authors)

  17. Preparation, Characterization and Stability Test of 177Lu-CTMP as Palliative Agent For Bone Pain Metastases

    177Lu-CTMP is an ideal radiopharmaceutical for palliative agent on bone pain metastases. This radiopharmaceutical was synthesized from cyclic polyaminophosphonic ligand, known as 1,4,8,11-tetraazacycIotetradecane-l, 4,8,11 tetramethylene phosphonic acid (CTMP) and labeled with 177Lu radio nuclide, a beta emitter which has long enough half life (t1/2=6.71 days, E β-max= 497 KeV). The labeling method was modified from Tapas Das Method by changing buffer type. Ammonium carbonate buffer was changed by phosphate buffer. In this research some variables were used. such as mol comparison (Lu:CTMP), pH variation, and reaction temperature. The result, indicated that an optimum condition of 177Lu-ClMP preparation was at mol comparison Lu:CTMP= 1:20, pH=7, and at room temperature. Optimum labeling of 177Lu-CTMP has been tested using paper chromatography, giving 99.4 % of radiochemical purity. From the stability test, it was found that the radiopharmaceutical was stable until 10 days (when it stored in room temperature and 4°C). After 10 days, decreasing of radiochemical purity, was found if stored in room temperature ( below of the required radiochemical purity «95%)). However, when it was stored at 4°C, it was stable until 21 days with a good condition (radiochemical purity >95%). (author)

  18. Tumor response assessment to treatment with [177Lu-DOTA0,Tyr3]octreotate in patients with gastroenteropancreatic and bronchial neuroendocrine tumors: differential response of bone versus soft-tissue lesions.

    Vliet, E.I. van; Hermans, J.J.; Ridder, M.A. de; Teunissen, J.J.; Kam, B.L.; Krijger, R.R. de; Krenning, E.P.; Kwekkeboom, D.J.

    2012-01-01

    We have noted that bone lesions on CT respond differently from soft-tissue lesions to treatment with [(177)Lu-DOTA(0),Tyr(3)]octreotate ((177)Lu-octreotate). We therefore compared the response of bone lesions with that of soft-tissue lesions to treatment with (177)Lu-octreotate in patients with gast

  19. Anti-EGFRvIII monoclonal antibody armed with {sup 177}Lu: in vivo comparison of macrocyclic and acyclic ligands

    Hens, Marc; Vaidyanathan, Ganesan; Zhao Xiaoguang [Department of Radiology, Duke University Medical Center, Durham, NC 27710 (United States); Bigner, Darell D. [Department of Pathology, Duke University Medical Center, Durham, NC 27710 (United States); Zalutsky, Michael R., E-mail: zalut001@mc.duke.ed [Department of Radiology, Duke University Medical Center, Durham, NC 27710 (United States)

    2010-10-15

    Introduction: Monoclonal antibody (mAb) L8A4 binds specifically to the epidermal growth factor receptor variant III (EGFRvIII) that is present on gliomas but not on normal tissues, and is internalized rapidly after receptor binding. Because of the short range of its {beta}-emissions, labeling this mAb with {sup 177}Lu would be an attractive approach for the treatment of residual tumor margins remaining after surgical debulking of brain tumors. Materials and Methods: L8A4 mAb was labeled with {sup 177}Lu using the acyclic ligands [(R)-2-amino-3-(4-isothiocyanatophenyl)propyl]-trans-(S,S)-cyclohexane-1, 2-diamine-pentaacetic acid (CHX-A''-DTPA) and 2-(4-isothiocyanatobenzyl)-6-methyldiethylene-triaminepentaacetic acid (1B4M-DTPA), and the macrocyclic ligands S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane-tetraacetic acid (C-DOTA) and {alpha}-(5-isothiocyanato-2-methoxyphenyl)-1,4,7,10-tetraazacyclododecane-1,4,7, 10-tetraacetic acid (MeO-DOTA). Paired-label tissue distribution experiments were performed in athymic mice bearing subcutaneous EGFRvIII-expressing U87.{Delta}EGFR glioma xenografts over a period of 1 to 8 days to directly compare {sup 177}Lu-labeled L8A4 to L8A4 labeled with {sup 125}I using N-succinimidyl 4-guanidinomethyl-3-[{sup 125}I]iodobenzoate ([{sup 125}I]SGMIB). Results: Except with C-DOTA, tumor uptake for the {sup 177}Lu-labeled mAb was significantly higher than the co-administered radioiodinated preparation; however, this was also the case for spleen, liver, bone and kidneys. Tumor/normal tissue ratios for {sup 177}Lu-1B4M-DTPA-L8A4 and, to an even greater extent, {sup 177}Lu-MeO-DOTA-L8A4 were higher than those for [{sup 125}I]SGMIB-L8A4 in most other tissues. Conclusions: Tumor and normal tissue distribution patterns for this anti-EGFRvIII mAb were dependent on the nature of the bifunctional chelate used for {sup 177}Lu labeling. Optimal results were obtained with 1B4M-DTPA and MeO-DOTA, suggesting no clear advantage

  20. Anti-EGFRvIII monoclonal antibody armed with 177Lu: in vivo comparison of macrocyclic and acyclic ligands

    Introduction: Monoclonal antibody (mAb) L8A4 binds specifically to the epidermal growth factor receptor variant III (EGFRvIII) that is present on gliomas but not on normal tissues, and is internalized rapidly after receptor binding. Because of the short range of its β-emissions, labeling this mAb with 177Lu would be an attractive approach for the treatment of residual tumor margins remaining after surgical debulking of brain tumors. Materials and Methods: L8A4 mAb was labeled with 177Lu using the acyclic ligands [(R)-2-amino-3-(4-isothiocyanatophenyl)propyl]-trans-(S,S)-cyclohexane-1, 2-diamine-pentaacetic acid (CHX-A''-DTPA) and 2-(4-isothiocyanatobenzyl)-6-methyldiethylene-triaminepentaacetic acid (1B4M-DTPA), and the macrocyclic ligands S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane-tetraacetic acid (C-DOTA) and α-(5-isothiocyanato-2-methoxyphenyl)-1,4,7,10-tetraazacyclododecane-1,4,7, 10-tetraacetic acid (MeO-DOTA). Paired-label tissue distribution experiments were performed in athymic mice bearing subcutaneous EGFRvIII-expressing U87.ΔEGFR glioma xenografts over a period of 1 to 8 days to directly compare 177Lu-labeled L8A4 to L8A4 labeled with 125I using N-succinimidyl 4-guanidinomethyl-3-[125I]iodobenzoate ([125I]SGMIB). Results: Except with C-DOTA, tumor uptake for the 177Lu-labeled mAb was significantly higher than the co-administered radioiodinated preparation; however, this was also the case for spleen, liver, bone and kidneys. Tumor/normal tissue ratios for 177Lu-1B4M-DTPA-L8A4 and, to an even greater extent, 177Lu-MeO-DOTA-L8A4 were higher than those for [125I]SGMIB-L8A4 in most other tissues. Conclusions: Tumor and normal tissue distribution patterns for this anti-EGFRvIII mAb were dependent on the nature of the bifunctional chelate used for 177Lu labeling. Optimal results were obtained with 1B4M-DTPA and MeO-DOTA, suggesting no clear advantage for acyclic vs. macrocyclic ligands for this application.

  1. Treatment of neuroendocrine tumors (NETs) expressing SMT 90Y and 177Lu

    Neuroendocrine tumors (NETs) are a relatively rare and extremely heterogeneous group, essentially characterized by a different metabolism and endocrine histologically pattern. NETs are a challenge for physicians not only for diagnosis but also for early treatment. In addition to this, QT or RT treatments that require a high rate of cell proliferation to be effective, they are not in these tumors as slow growth. The primary treatment of NETs is surgery, either with a curative intent or tumor shrinkage. Peptide Receptors Radiotherapy (RTPR) consists of the administration for therapeutic purposes of Radiolabeled Synthetic Peptides that bind specifically and with high affinity to receptors of tumor cells. The RTPR of TNE with SMT analogues is effective for handling or metastizados inoperable patients. The Conference gives an accurate picture of the treatment of these tumors both 90Y as 177Lu. (author)

  2. Study On Preparation Of 177Lu-EDTMP For Metastatic Bone Pain Palliation Treatment

    Ethylene diamine tetramethylene phosphonate (EDTMP) is one of the most widely used ligands which forms stable complexes with various radionuclides and all the complexes showed high bone uptake in biodistribution studies. EDTMP has a high affinity to skeleton and osteoblastic bone metastases and many EDTMP chelates posses a considerably high stability.This stimulated application of the ligand as the in-vivo carrier of various radionuclides, intended for both therapy and diagnosis of osteoblastic lesions.The present study intends to formulate EDTMP kits, label them with 177Lu, quality control and in-vitro stability studies. This paper presents some research results on the optimal conditions for labeling EDTMP kit with Lu-177 of low specific activity that was produced on the IVV-9 reactor at the Nuclear Research Institute. (author)

  3. Effect of amplified spontaneous emission on selectivity of laser photoionisation of the 177Lu radioisotope

    D'yachkov, A. B.; Gorkunov, A. A.; Labozin, A. V.; Mironov, S. M.; Panchenko, V. Ya; Firsov, V. A.; Tsvetkov, G. O.

    2016-06-01

    A significant deselecting effect of amplified spontaneous emission has been observed in the experiments on selective laser photoionisation of the 177Lu radioisotope according to the scheme 5d6s2 2D3/2 → 5d6s6p 4Fo5/2 (18505 cm-1) → 5d6s7s 4D3/2(37194 cm-1) → autoionisation state (53375 cm-1). The effect is conditioned by involvement of non-target isotopes from the lower metastable level 5d6s2 2D5/2(1994 cm-1) into the ionisation process. Spectral filtering of spontaneous emission has allowed us to significantly increase the selectivity of the photoionisation process of the radioisotope and to attain a selectivity value of 105 when using saturating light intensities.

  4. Preparation and Evaluation of 177Lu Labeled Nitroimidazole Derivative for Targeting Tumor Hypoxia

    Hypoxia has been known be an important physiological parameter for tumor growth and has been reported to be the cause for poor response to chemotherapy. Mechanistically, tumor hypoxia results from an imbalance between oxygen delivery and oxygen consumption. The identification and quantification of tumor hypoxia may predict the out come and may identify patients who might benefit from concomitant radiosensitizing therapy to overcome the hypoxia effect. In nuclear medicine, there is an interesting observation that nitroimidazole derivatives can selectively accumulate in the hypoxic regions, a character of a good radiosensitizer. In this study, we have synthesized a 2-nitroimidazole derivative containing a DOTA chelator by using a solid phase reaction. The nitroimidazole analogue was radiolabeled with 177Lu. Furthermore biodistribution study was performed to evaluate its tissue uptake, in vivo

  5. Hydroxyapatite Based 99Mo-99mTc and 188W-188Re Generator Systems

    This paper describes studies evaluating the use of hydroxyapatite as the adsorbent material for both 99Mo-99mTc and 188W-188Re generator systems. Hydroxyapatite is an insoluble solid with anion exchange properties. A study of the sorption behaviour of 99Mo, 99mTc, 188W and 188Re on hydroxyapatite in NaCl medium was evaluated by batch experiments. The results demonstrated that while 99Mo, 99mTc and 188Re are not adsorbed by the hydroxyapatite in NaCl solutions (Kd 188W is strongly adsorbed (Kd >500). On the basis of these measurements, hydroxyapatite 188W-188Re generator systems were then constructed and eluted in NaCl solutions. The hydroxyapatite based 188W-188Re generator performances are presented

  6. In vitro characterization of 177Lu-radiolabelled chimeric anti-CD20 monoclonal antibody and a preliminary dosimetry study

    131I- and 90Y-labelled anti-CD20 antibodies have been shown to be effective in the treatment of low-grade, B-cell non-Hodgkin's lymphoma (NHL). However, the most appropriate radionuclide in terms of high efficiency and low toxicity has not yet been established. In this study we evaluated an immunoconjugate formed by the anti-CD20 antibody rituximab and the chelator DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid). DOTA-rituximab was prepared as a kit formulation and can be labelled in a short time (177Lu or 90Y. Immunoconjugates with different numbers of DOTA molecules per rituximab were prepared using p-SCN-Bz-DOTA. In vitro immunoreactivity and stability were tested and preliminary dosimetric results were acquired in two patients. The immunological binding properties of DOTA-rituximab to the CD20 antigen were found to be retained after conjugation with up to four chelators. The labelled product was stable against a 105 times excess of diethylenetriaminepentaacetic acid (DTPA, 37 C, 7 days). Two patients with relapsed NHL were treated with 740 MBq/m2 body surface 177Lu-DOTA-rituximab. Scintigraphic images showed specific uptake at tumour sites and acceptable dosimetric results. The mean whole-body dose was found to be 314 mGy. The administration of 177Lu-DOTA-rituximab was tolerated well. Our results show that DOTA-rituximab (4:1) can be labelled with 177Lu with sufficient stability while the immunoconjugate retains its immunoreactivity. 177Lu-DOTA-rituximab is an interesting, well-tolerated radiolabelled antibody with clinical activity in a low dose range, and provides an approach to the efficient treatment with few side effects for patients with relapsed NHL. (orig.)

  7. Pharmacokinetics of radioimmunotherapeutic agent of direct labeling mAb 188Re-HAb18

    Chao Lou; Zhi-Nan Chen; Hui-Jie Bian; Jie Li; Shou-Bo Zhou

    2002-01-01

    AIM: To labed Anti-hepatoma monoclonal antibody (mAb)fragment HAb18 F (ab')2 was labeled with 188 Re for thepharmacokinetic model of 188 Re-HAb18 F (ab')2 and toevaluate its pharmacokinetic parameters in hepatoma-bearing nude mice.METHODS: HAb18 F(ab')2 was directly labeled with 188Reusing 2-mercaptoethanol (2-ME) as reducing agents.Labeling efficiency and immunoreactivity of 188 Re-HAb18 F( ab')2 were evaluated by Whatman 3MM paperchromatography and live cell assay, respectively.Biodiatribution analysis was also conducted in nude micebearing human hepatoma in which animals were sacrificed atdifferent time points(1, 4, 18, 24 and 24h) after 188Re-HAb18F(ab' )2 was injected through tail-vein into hepatoma-bearingnude mice. The blood and radioactivity of organs and masswere measured. The concentrations of 188 Re-HAb18 F(ab')2were evaluated with a pharmacokinetic 3P97 software.RESULTS: The optimum labeling efficiency andimmunoreactive fraction were 91.7% and 0.78%,respectively. The parameters of 188Re-HAb18 F(ab')2 were:T1/2, 2.29h; Vd, 1.49 × 10-9L@ Bq- 1; AUC, 20.49 × 109Bq@ h@L-1 ;CL, 0.45 × 10-3L@ h- 1. 188Re- HAb18 F(ab')2 could locatespecially in hepatoma with high selective reactivity of HAb18F(ab')2. 188 Re-HAb18 F(ab')2 was mainly eliminated bykidney. The maximal tumor to blood ratio was at 48h, andmaximal tumor to liver ratio was at 18h.CONCLUTION: The pharmacokinetics of 188Re-HAb18 F(ab')2fit a I-compartment model. 188 Re-HAb18 F(ab')2 can beuptaken selectively at the hepatoma site.

  8. Formulation of a freeze-dried kit for 188Re-MAG3 and its quality control

    The synthesis of 188Re-MAG3 is described using 188Re, which was obtained from the alumina based 188W/188Re generator. Dependence of the radiolabeling yields of 188Re-MAG3 on reducing agent concentration, Bz-MAG3 concentration, pH, temperature and incubation time was examined. In the case of optimum conditions the yield of 188Re-MAG3 was 98%. TLC and HPLC techniques were employed to monitor the different species formed. Biodistribution study of 188Re-MAG3 was carried out in rats and compared with behavior of 99mTc-MAG3. (author)

  9. The in vivo disposition and in vitro transmembrane transport of two model radiometabolites of DOTA-conjugated receptor-specific peptides labelled with (177) Lu.

    Volková, Marie; Mandíková, Jana; Bárta, Pavel; Navrátilová, Lucie; Lázníčková, Alice; Trejtnar, František

    2015-01-01

    In vivo metabolism of the radiolabelled receptor-specific peptides has been described; however, information regarding the pharmacokinetic behaviour of the degradation products within the body is very scarce. The present study was designed to obtain new knowledge on the disposition and elimination of low-molecular radiometabolites of receptor-specific peptides in the organism and to reveal the potential involvement of selected membrane transport mechanisms in the cellular uptake of radiometabolites, especially in the kidney. The study compared pharmacokinetics of two radiometabolites: a final metabolite of somatostatin analogues, (177)Lu-DOTA-DPhe, and a tripeptide metabolite of (177)Lu-DOTA-minigastrin 11, (177)Lu-DOTA-DGlu-Ala-Tyr. Their pharmacokinetics was compared with that of respective parent (177)Lu-radiopeptide. Both radiometabolites exhibited relative rapid clearing from most body tissues in rats in vivo along with predominant renal excretion. The long-term renal retention of the smaller radiometabolite (177)Lu-DOTA-DPhe was lower than that of (177)Lu-DOTA-DGlu-Ala-Tyr. An uptake of (177)Lu-DOTA-DPhe by human renal influx transporter organic cation transporter 2 was found in vitro in a cellular model. The study brings the first experimental data on the in vivo pharmacokinetics of radiometabolites of receptor-specific somatostatin and gastrin analogues. The found results may indicate a negative correlation between the degree of decomposition of the parent peptide chain and the renal retention of the metabolite. PMID:26526343

  10. Production, quality control, biodistribution assessment and preliminary dose evaluation of [177Lu]-tetra phenyl porphyrin complex as a possible therapeutic agent

    Samaneh Zolghadri

    2015-06-01

    Full Text Available Due to interesting therapeutic properties of 177Lu and tumor avidity of tetraphenyl porphyrins (TPPs, 177Lu-tetraphenyl porphyrin was developed as a possible therapeutic compound. 177Lu of 2.6-3 GBq/mg specific activity was obtained by irradiation of natural Lu2O3sample with thermal neutron flux of 4 × 1013 n.cm-2.s-1. Tetraphenyl porphyrin was synthetized and labeled with 177Lu. Radiochemical purity of the complex was studied using Instant thin layer chromatography (ITLC method. Stability of the complex was checked in final formulation and human serum for 48 h. The biodistribution of the labeled compound in vital organs of wild-type rats was studied up to 7 d. The absorbed dose of each human organ was calculated by medical internal radiation dose (MIRD method. A detailed comparative pharmacokinetic study was performed for 177Lu cation and [177Lu]-TPP. The complex was prepared with a radiochemical purity: >97±1% and specific activity: 970-1000 MBq/mmol. Biodistribution data and dosimetric results showed that all tissues receive approximately an insignificant absorbed dose due to rapid excretion of the complex through the urinary tract. [177Lu]-TPP can be an interesting tumor targeting agent due to low liver uptake and very low absorbed dose of approximately 0.036 to the total body of human.

  11. Labelling of Dotatate with 177Lu and 131I for diagnosis and targeted therapy: In vitro and In vivo comparative evaluation

    The studies focused on the radiolabelling of DOTA-Tyr3-TATE (DOTATATE) with 177Lu and 131I, on the biological behaviour of 177Lu-DOTATATE and 131IDOTATATE and on comparative evaluation of the results obtained to select an appropriate radiopeptide for potential application in somatostatin receptor radionuclide therapy. The radiopeptides were obtained with high purities and specific activities, but with different stabilities, with the 177Lu-DOTATATE being more stable than the 131IDOTATATE. The results of competition and saturation binding experiments using rat brain cortex membrane homogenates show a high in vitro affinity (IC50: 4.74nM, Kd: 142.8 for 177Lu-DOTATATE; IC50: 1.28nM, Kd: 157.6 for 131I-DOTATATE). The biodistribution of each radiopeptide as well as the competitive biodistribution of 177Lu- DOTATATE and 131I-DOTATATE in rats bearing HRS1 (Hepatom RS1, a hepatocolangiom carcinoma) tumours illustrate that 177Lu-DOTATATE is more stable and shows better tumour uptake than 131I-DOTATATE, and that the competitive localization index of 177Lu-DOTATATE is three times higher than that of 131I-DOTATATE. The flow cytometry measurements of the HRS1 tumour samples from rats treated with multiple doses of 177Lu-DOTATATE in combination with absorbed dose data show decreases of both the tumour cell proliferation index and DNA ploidy. These data indicate that 177Lu- DOTATATE is a good option for application in somatostatin receptor radionuclide therapy. (author)

  12. 177Lu medical radioisotope separation from Yb-Lu matrix irradiated pass through ion exchanger resin by eluent of α-Hiba and HNO3 solution

    Since a few last year, Lutetium-177 ( 177Lu) have come to be one of lanthanide radioisotopes which is widely used for the purpose of therapy. Radioisotope of 177Lu emit β-radiation with energy of 497 keV ( 78 %) that is ideal for therapeutical treatment of soft-tissue tumor. It also emits γ-radiation energy of 208 keV (12 %) that is suitable for imaging technique. The characteristic of the emitted radiation energies are as well supported by its physical half live of 6.65 days that makes radioisotope 177Lu to be a choice in the field of nuclear medicine. The domestic capability on the production of carrier free 177Lu do not support yet the wide application of 177Lu. This present proposal is arrived to learn and to master the production of carrier free 177Lu based on nuclear reaction of 176Yb(n,γ) 177Yb. The production process method of carrier free 177Lu is involved separation technique of 177Lu from the matrix of post-irradiated natural Yb, will be performed based on column chromatographic separation using stationary phase of ion exchanger. Comparison Lu/Yb in the Yb-Lu bulk solution in fraction the introduction experiment from the A trial to the E trial that he thought between 0.137 s/he 0.0198 almost resemble the radioisotope comparison 177Lu/ 175Yb in the Yb-Lu bulk solution that he thought between 0.157 s/he 0.0211. Meaning that the introduction experiment of the above still cannot separate the species 177Lu radionuclides from solder Lu-Yb irradiated. In two trials of the optimisation is received by results of Lu/Yb comparison respectively of 18.794 and 25,537 respectively in the fraction 43 compared with Lu/Yb comparison in the Yb-Lu bulk solution that is their respective only of 0.0312. This shows the existence of the separation of the species 177Lu radionuclide from the matrix Yb-You irradiated. The condition for the trial of this optimisation must be evaluated further to receive the separation 177Lu radionuclide from the matrix Yb-Lu that is better

  13. Rhenium-188: Availability from the W-188/Re-188 Generator and Status of Current Applications

    Pillai, M R A [Bhabha Atomic Research Centre, Mumbai, India; Dash, A [Bhabha Atomic Research Centre, Mumbai, India; Knapp Jr, Russ F [ORNL

    2012-01-01

    Rhenium-188 is one of the most readily available generator derived and useful radionuclides for therapy emitting - particles (2.12 MeV, 71.1% and 1.965 MeV, 25.6%) and imageable gammas (155 KeV, 15.1%). The 188W/188Re generator is an ideal source for the long term (4-6 months) continuous availability of no carrier added (nca) 188Re suitable for the preparation of radiopharmaceuticals for radionuclide therapy. The challenges associated with the double neutron capture route of production of the parent 188W radionuclide have been a major impediment in the progress of application of 188Re. Tungsten-188 of adequate specific activity can be prepared only in 2-3 of the high flux reactors operating in the World. Several useful technologies have been developed for the preparation of clinical grade 188W/188Re generator. Since the specific activity of 188W used in the generator is relatively low (<5 Ci/g), the eluted 188ReO4- can have low radioactive concentration often insufficient for radiopharmaceutical preparation. However, several efficient post elution concentration techniques have been developed that yield clinically useful 188ReO4-. Rhenium-188 has been used for the preparation of therapeutic radiopharmaceuticals for the management of diseases such as bone metastasis, rheumatoid arthritis and primary cancers. Several early phase clinical studies using radiopharmaceuticals based on 188Re-labeled phosphonates, antibodies, peptides, lipiodol and particulates have been reported. This article reviews the availability, and use of188Re including a discussion of why broader use of 188Re has not progressed as ecpected as a popular radionuclide for therapy.

  14. Stability of 188Re Labeled antibody for radioimmunotherapy and the effect of stabilizing agents

    For clinical application of beta-emitter labeled antibody, high specific activity is important. Carrier-free 188Re from 188W/ 188Re generator is an ideal radionuclide for this purpose. However, low stability of 188Re labeled antibody, especially in high specific activity, due to radiolytic decomposition by high energy (2.1 MeV) beta ray was problem. We studied the stability of 188Re labeled antibody, and stabilizing effect of several stabilizers. Pre-reduced monoclonal antibody (CEA79.4) was labeled with 188Re by incubating with generator-eluted 188Re-perrhenate in the presence of stannous tartrate for 2 hr at room temperature. Radiochemical purity of each preparation was determined by chromatography. Human serum albumin was added to the labeled antibodies (2%). Stability of 188Re-CEA79.4 was investigated in the presence of ascorbic acid, ethanol, or Tween 80 as stabilizing agents. Labeling efficiencies were 88±4% (n=12). Specific activities of 1.25 ∼4.77 MBq/μg were obtained. If stored after purging with N2, all the preparations were stable for 10 hr. However, stability decreased in the presence of air. Perrhenate and 188Re-tartrate was major impurity in declined preparation. Colloid-formation was not a significant problem in all cases. Addition of ascorbic acid stabilized the labeled antibodies either under N2 or under air by reducing the formation of perrhenate. High specific activity 188Re labeled antibody is unstable, especially, in the presence of oxygen. Addition of ascorbic acid increased the stability

  15. Preparation and biodistribution of 188Re-labeled folate conjugated human serum albumin magnetic cisplatin nanoparticles (188Re-folate-CDDP/HSA MNPs in vivo

    Tang QS

    2011-11-01

    Full Text Available Qiu-Sha Tang1,*, Dao-Zhen Chen2,*, Wen-Qun Xue2, Jing-Ying Xiang2, Yong-Chi Gong1, Li Zhang2, Cai-Qin Guo21Department of Pathology and Pathophysiology, Medical College, Southeast University, Nanjing, Jiangsu; 2Central Laboratory, Wuxi Hospital for Maternal and Child Health Care, Affiliated Medical School of Nanjin, Wuxi, Jiangsu, China *Authors contributed equally to this workBackground: The purpose of this study was to develop intraperitoneal hyperthermic therapy based on magnetic fluid hyperthermia, nanoparticle-wrapped cisplatin chemotherapy, and magnetic particles of albumin. In addition, to combine the multiple-killing effects of hyperthermal targeting therapy, chemotherapy, and radiotherapy, the albumin-nanoparticle surfaces were linked with radionuclide 188Re-labeled folic acid ligand (188Re-folate-CDDP/HSA.Methods: Human serum albumin was labeled with 188Re using the pre-tin method. Reaction time and optimal conditions of labeling were investigated. The particles were intravenously injected into mice, which were sacrificed at different time points. Radioactivity per gram of tissue of percent injected dose (% ID/g was measured in vital organs. The biodistribution of 188Re-folate-CDDP/HAS magnetic nanoparticles was assessed.Results: Optimal conditions for 188Re-labeled folate-conjugated albumin combined with cisplatin magnetic nanoparticles were: 0.1 mL of sodium gluconate solution (0.3 mol/L, 0.1 mL of concentrated hydrochloric acid with dissolved stannous chloride (10 mg/mL, 0.04 mL of acetic acid buffer solution (pH 5, 0.2 mol/L, 30 mg of folate-conjugated albumin combined with cisplatin magnetic nanoparticles, and 188ReO4 eluent (0.1 mL. The rate of 188Re-folate-CDDP-HSA magnetic nanoparticle formation exceeded 90%, and radiochemical purity exceeded 95%. The overall labeling rate was 83% in calf serum at 37°C. The major uptake tissues were the liver, kidney, intestine, and tumor after the 188Re-folate-CDDP/HSA magnetic nanoparticles

  16. Automation of the synthesis of highly concentrated 188Re-MAG3 for intracoronary radiation therapy

    We have developed an efficient method and an automated synthetic system for the preparation of highly concentrated 188Re-MAG3. Routine production of 188Re-MAG3 for use in intracoronary radiation therapy was performed by compressed air driven semi-automated shielded system. 188Re-MAG3 was prepared with a commercial kit and reducing agents, purified and concentrated by C18 Sep-Pak cartridges to desired radioactivity and volume. Using this automated system, reproducible radiolabeling yields of 80-85% were obtained

  17. Production and purification of the {sup 161} Tb, {sup 149} Pm, {sup 166} Ho and {sup 177} Lu radioisotopes; Produccion y purificacion de los radioisotopos {sup 161} Tb, {sup 149} Pm, {sup 166} Ho y {sup 177} Lu

    Jaime S, E. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)

    2007-07-01

    The present thesis work this constituted by four chapters; the theoretical mark is the first of them, in this chapter an introduction it is presented where is showed the characteristics and importance of the study of the lanthanides in nuclear medicine, as well as the theoretical bases of the analytical methods and of characterization used in this work. The second chapter it describes the methodology followed in the experimental part; while the third chapter shows the obtained results in the separation and purification of the radioisotopes: {sup 149} Pm, {sup 161} Tb, {sup 166} Ho, and {sup 177} Lu. In the fourth chapter the obtained conclusions of this study work are presented where it was concluded that it can separate and to purify the radioisotopes: {sup 149} Pm, {sup 161}Tb, {sup 166} Ho and {sup 177} Lu using the column extraction chromatography. (Author)

  18. Fast voxel-level dosimetry for 177Lu labelled peptide treatments

    Hippeläinen, E.; Tenhunen, M.; Sohlberg, A.

    2015-09-01

    In peptide receptor radionuclide therapy (PRRT), voxel-level radiation absorbed dose calculations can be performed using several different methods. Each method has it strengths and weaknesses; however, Monte Carlo (MC) simulation is presently considered the most accurate method at providing absorbed dose distributions. Unfortunately MC simulation is time-consuming and often impractical to carry out in a clinical practice. In this work, a fast semi-Monte Carlo (sMC) absorbed dose calculation method for 177Lu PRRT dosimetry is presented. The sMC method is based on a local electron absorption assumption and fast photon MC simulations. The sMC method is compared against full MC simulation code built on PENELOPE (vxlPen) using digital phantoms to assess the accuracy of these assumptions. Due to the local electron absorption assumption of sMC, the potential errors in cross-fire dose from electrons and photons emitted by 177Lu were first evaluated using an ellipsoidal kidney model by comparing vxlPen and sMC. The photon cross-fire dose from background to kidney and kidney to background with varying kidney-to-background activity concentration ratios were calculated. In addition, kidney to kidney photon and electron cross-dose with different kidney to kidney distances were studied. Second, extended cardiac-torso (XCAT) phantoms were created with liver lesions and with realistic activity distributions and tissue densities. The XCAT phantoms were used to simulate SPECT projections and 3D activity distribution images were reconstructed using an OSEM algorithm. Image-based dose rate distributions were calculated using vxlPen and sMC. Total doses and dose rate volume histograms (DrVH) produced by the two methods were compared. The photon cross-fire dose from the kidney increased the background’s absorbed dose by 5% or more up to 5.8 cm distance with 20 : 1 kidney to background activity concentration ratio. On the other hand, the photon cross-fire dose from the background to

  19. Fast voxel-level dosimetry for 177Lu labelled peptide treatments

    In peptide receptor radionuclide therapy (PRRT), voxel-level radiation absorbed dose calculations can be performed using several different methods. Each method has it strengths and weaknesses; however, Monte Carlo (MC) simulation is presently considered the most accurate method at providing absorbed dose distributions. Unfortunately MC simulation is time-consuming and often impractical to carry out in a clinical practice. In this work, a fast semi-Monte Carlo (sMC) absorbed dose calculation method for 177Lu PRRT dosimetry is presented. The sMC method is based on a local electron absorption assumption and fast photon MC simulations. The sMC method is compared against full MC simulation code built on PENELOPE (vxlPen) using digital phantoms to assess the accuracy of these assumptions.Due to the local electron absorption assumption of sMC, the potential errors in cross-fire dose from electrons and photons emitted by 177Lu were first evaluated using an ellipsoidal kidney model by comparing vxlPen and sMC. The photon cross-fire dose from background to kidney and kidney to background with varying kidney-to-background activity concentration ratios were calculated. In addition, kidney to kidney photon and electron cross-dose with different kidney to kidney distances were studied. Second, extended cardiac-torso (XCAT) phantoms were created with liver lesions and with realistic activity distributions and tissue densities. The XCAT phantoms were used to simulate SPECT projections and 3D activity distribution images were reconstructed using an OSEM algorithm. Image-based dose rate distributions were calculated using vxlPen and sMC. Total doses and dose rate volume histograms (DrVH) produced by the two methods were compared.The photon cross-fire dose from the kidney increased the background’s absorbed dose by 5% or more up to 5.8 cm distance with 20 : 1 kidney to background activity concentration ratio. On the other hand, the photon cross-fire dose from the background to

  20. MicroSPECT/CT imaging and pharmacokinetics of 188Re-(DXR)-liposome in human colorectal adenocarcinoma-bearing mice.

    Chen, Min-Hua; Chang, Chih-Hsien; Chang, Ya-Jen; Chen, Liang-Cheng; Yu, Chia-Yu; Wu, Yu-Hsien; Lee, Wan-Chi; Yeh, Chung-Hsin; Lin, Feng-Huei; Lee, Te-Wei; Yang, Chung-Shi; Ting, Gann

    2010-01-01

    Nanoliposome can be designed as a drug delivery carrier to improve the pharmacological and therapeutic properties of drug administration. (188)Re-labeled nanoliposomes are useful for diagnostic imaging as well as for targeted radionuclide therapy. In this study, the in vivo nuclear imaging, pharmacokinetics and biodistribution of administered nanoliposomes were investigated as drug and radionuclide carriers for targeting solid tumor via intravenous (i.v.) administration. The radiotherapeutics ((188)Re-liposome) and radiochemotherapeutics ((188)Re-DXR-liposome) were i.v. administered to nude mice bearing human HT-29 colorectal adenocarcinoma xenografts. (188)Re-liposome and (188)Re-DXR-liposomes show similar biodistribution profile; both have higher tumor uptake, higher blood retention time, and lower excretion rate than (188)Re-N,N-bis(2-mercaptoethyl)-N',N'-diethylenediamine (BMEDA). In contrast to tumor uptake, the area under the curve (AUC) value of tumor for (188)Re-liposome and (188)Re-DXR-liposome was 16.5- and 11.5-fold higher than that of free (188)Re-BMEDA, respectively. Additionally, (188)Re-liposome and (188)Re-DXR-liposome had a higher tumor-to-muscle ratio at 24 h (14.4+/-2 .7 and 17.14+/-4.1, respectively) than (188)Re-BMEDA (1.6+/-0.1). The tumor targeting and distribution of (188)Re-(DXR)-liposome (representing (188)Re-DXR-liposome and (188)Re-liposome) can also be acquired by signal photon-emission computed tomography/computed tomography images as well as whole body autoradiograph. These results suggest that (188)Re-(DXR)-liposomes are potentially promising agents for passive targeting treatment of malignant disease. PMID:20150618

  1. Evaluation of the therapeutic efficacy and radiotoxicity of the conjugates 177Lu-DOTA-E-c(RGDfK)2 and 177Lu-DOTA-GGC-AuNP-c[RGDfk(C)] in a murine model and their relationship with the inhibition of the angiogenic factors VEGF and HIF-1α

    Molecular targeting therapy has become a relevant therapeutic strategy for cancer. The principle that peptide receptors can be used successfully for in vivo targeting of human cancers has been proven, and radiolabeled peptides have been demonstrated to be effective in patients with malignant tumors. Peptides based on the cyclic Arg-Gly-Asp (RGD) sequence have been designed to antagonize the function of α(v)β(3) integrin, thereby inhibiting angio genesis. The conjugation of RGD peptides to radiolabeled gold nanoparticles (AuNP) produces biocompatible and stable m ultimeric systems with target-specific molecular recognition. The aim of this research was to evaluate the therapeutic response of 177Lu-AuNP-RGD in athymic mice bearing α(v)β(3)-integrin-positive C6 gliomas and compare with that of 177Lu-AuNP or 177Lu-RGD. The radiation absorbed dose, metabolic activity (SUV, [18F]fluor-deoxy-glucose-micro PET/CT), renal radiotoxicity, renal and tumoral histological characteristics as well as tumoral VEGF and HIF-1? gene expression (by realtime polymerase chain reaction) following treatment with 177Lu-AuNP-RGD, 177Lu-AuNP or 177Lu-RGD were assessed. Of the radiopharmaceuticals evaluated, 177Lu-AuNP-RGD delivered the highest tumor radiation absorbed dose (63.8 ± 7.9 Gy) vs other treatments. These results correlated with the observed therapeutic response, in which 177Lu-AuNP-RGD significantly (p177Lu). There was a low uptake in non-target organs and no induction of renal toxicity. 177Lu-AuNP-RGD demonstrates properties suitable for use as an agent for molecular targeting radiotherapy. (Author)

  2. Formation of medical radioisotopes 111In, 117mSn, 124Sb, and 177Lu in photonuclear reactions

    The possibility of the photonuclear production of radioisotopes 111In, 117mSn, 124Sb, and 177Lu is discussed. Reaction yields were measured by the gamma-activation method. The enriched tin isotopes 112, 118Sn and Te and HfO2 of natural isotopic composition were used as targets. The targets were irradiated at the linear electron accelerator of Alikhanian National Science Laboratory (Yerevan) at the energy of 40 MeV. The experimental results obtained in this way reveal that the yield and purity of radioisotopes 111In and 117mSn are acceptable for their production via photonuclear reactions. Reactions proceeding on targets from Te and HfO2 of natural isotopic composition and leading to the formation of 124Sb and 177Lu have small yields and are hardly appropriate for the photoproduction of these radioisotopes even in the case of enriched targets

  3. Preparation of 188 Re-lanreotide as a potential tumor therapeutic agent

    Radiolabeled peptides hold unlimited potential in diagnostic applications and therapy of malignant tumor. Somatostatin analogue peptide (Lanreotide) is labeled directly with 188Re via the mixture of citrate and tartrate. The influences of reaction conditions such as pH, temperature, amount of stannous chloride, Lanreotide quantity, reaction time on labeling yield are investigated in detail. At the same time, the stability in vitro, quality control and animal test are evaluated. The experimental results show that Lanreotide reacts with 188Re for 40 min at pH 2 - 3 and 60 degree C, the labeling yield is at range of 88% - 94%. After purification of 188Re-Lanreotide with Sep-Pak C18 reverse phase extraction cartridge, the radiochemical purity (RP) is more than 95%. 188Re-Lanreotide is eliminated rapidly from the blood and is excreted through liver, the uptake of lung and intestine is high

  4. {sup 177}Lu-immunotherapy of experimental peritoneal carcinomatosis shows comparable effectiveness to {sup 213}Bi-immunotherapy, but causes toxicity not observed with {sup 213}Bi

    Seidl, Christof; Zoeckler, Christine; Beck, Roswitha; Senekowitsch-Schmidtke, Reingard [Technische Universitaet Muenchen, Department of Nuclear Medicine, Munich (Germany); Quintanilla-Martinez, Leticia [Universitaetsklinikum Tuebingen, Institute for Pathology, Tuebingen (Germany); Bruchertseifer, Frank [Institute for Transuranium Elements, European Commission, Joint Research Centre, Karlsruhe (Germany)

    2011-02-15

    {sup 213}Bi-d9MAb-immunoconjugates targeting gastric cancer cells have effectively cured peritoneal carcinomatosis in a nude mouse model following intraperitoneal injection. Because the {beta}-emitter {sup 177}Lu has proven to be beneficial in targeted therapy, {sup 177}Lu-d9MAb was investigated in this study in order to compare its therapeutic efficacy and toxicity with those of {sup 213}Bi-d9MAb. Nude mice were inoculated intraperitoneally with HSC45-M2 gastric cancer cells expressing d9-E-cadherin and were treated intraperitoneally 1 or 8 days later with different activities of specific {sup 177}Lu-d9MAb immunoconjugates targeting d9-E-cadherin or with nonspecific {sup 177}Lu-d8MAb. Therapeutic efficacy was evaluated by monitoring survival for up to 250 days. For evaluation of toxicity, both biodistribution of {sup 177}Lu-d9MAb and blood cell counts were determined at different time points and organs were examined histopathologically. Treatment with {sup 177}Lu-immunoconjugates (1.85, 7.4, 14.8 MBq) significantly prolonged survival. As expected, treatment on day 1 after tumour cell inoculation was more effective than treatment on day 8, and specific {sup 177}Lu-d9MAb conjugates were superior to nonspecific {sup 177}Lu-d8MAb. Treatment with 7.4 MBq of {sup 177}Lu-d9MAb was most successful, with 90% of the animals surviving longer than 250 days. However, treatment with therapeutically effective activities of {sup 177}Lu-d9MAb was not free of toxic side effects. In some animals lymphoblastic lymphoma, proliferative glomerulonephritis and hepatocarcinoma were seen but were not observed after treatment with {sup 213}Bi-d9MAb at comparable therapeutic efficacy. The therapeutic efficacy of {sup 177}Lu-d9MAb conjugates in peritoneal carcinomatosis is impaired by toxic side effects. Because previous therapy with {sup 213}Bi-d9MAb revealed comparable therapeutic efficacy without toxicity it should be preferred for the treatment of peritoneal carcinomatosis. (orig.)

  5. 177Lu-immunotherapy of experimental peritoneal carcinomatosis shows comparable effectiveness to 213Bi-immunotherapy, but causes toxicity not observed with 213Bi

    213Bi-d9MAb-immunoconjugates targeting gastric cancer cells have effectively cured peritoneal carcinomatosis in a nude mouse model following intraperitoneal injection. Because the β-emitter 177Lu has proven to be beneficial in targeted therapy, 177Lu-d9MAb was investigated in this study in order to compare its therapeutic efficacy and toxicity with those of 213Bi-d9MAb. Nude mice were inoculated intraperitoneally with HSC45-M2 gastric cancer cells expressing d9-E-cadherin and were treated intraperitoneally 1 or 8 days later with different activities of specific 177Lu-d9MAb immunoconjugates targeting d9-E-cadherin or with nonspecific 177Lu-d8MAb. Therapeutic efficacy was evaluated by monitoring survival for up to 250 days. For evaluation of toxicity, both biodistribution of 177Lu-d9MAb and blood cell counts were determined at different time points and organs were examined histopathologically. Treatment with 177Lu-immunoconjugates (1.85, 7.4, 14.8 MBq) significantly prolonged survival. As expected, treatment on day 1 after tumour cell inoculation was more effective than treatment on day 8, and specific 177Lu-d9MAb conjugates were superior to nonspecific 177Lu-d8MAb. Treatment with 7.4 MBq of 177Lu-d9MAb was most successful, with 90% of the animals surviving longer than 250 days. However, treatment with therapeutically effective activities of 177Lu-d9MAb was not free of toxic side effects. In some animals lymphoblastic lymphoma, proliferative glomerulonephritis and hepatocarcinoma were seen but were not observed after treatment with 213Bi-d9MAb at comparable therapeutic efficacy. The therapeutic efficacy of 177Lu-d9MAb conjugates in peritoneal carcinomatosis is impaired by toxic side effects. Because previous therapy with 213Bi-d9MAb revealed comparable therapeutic efficacy without toxicity it should be preferred for the treatment of peritoneal carcinomatosis. (orig.)

  6. Therapeutic Efficacy with Treatment-related Toxicities of 177Lu-labeled Bombesin Derivative for the Peptide Receptor Radiotherapy

    The gastrin-releasing peptide receptor (GRPR) has been shown to be overexpressed in many human tumours, including breast cancer, prostate cancer, small cell lung cancer, ovarian cancers, endometrial cancers, and gastrointestinal stromal tumors. In particular, GRPR expression is high in 83 % of invasive primary prostatic carcinomas. These results suggest that 177Lu-labeled bombesin derivative has promising characteristics as a novel nuclear medicine, especially for the treatment of GRPR over-expressing prostate tumors

  7. Improvement in the 111In-DTPA-TYR3-octreotide and 177Lu-DOTATYR3- octreotate production

    Recent advances in receptor mediated-tumor imaging have resulted in the development of somatostatin analogues, the biomolecular basis for the clinical use of these compounds in nuclear medicine for diagnostic and peptide receptor radionuclide therapy (PRRT). PRRT is a very good therapeutic option for patients with metastatic neuroendocrine gastroenteropancreatic (GEP) tumour. Clinical studies with different sst-positives tumors proved advantages of [177Lu-DOTA-Tyr3]octreotate (DOTATATE) for therapy. The aim of this work is to establish and validate the labeling, the quality control procedures of DTPA-Tyr3-Octreotide (DTPA-Oct) and DOTA-Tyr3-Octreotate (DOTATATE) labeled with In-111 and Lu-177, respectively, for routine production at Radiopharmacy Directory (DIRF) Brazil. Labeling were performed in a 'glove-box' using 111InCl3 (Nordion) and in hot-cell with 177LuCl3 (IDB-Holland) at pH 4.5; using DTPA-Oct (Pichem) and DOTATATE (IDBHolland) at room temperature and at 82-85 deg C for 30 minutes, respectively. The radiochemical purity was determined by ITLC-SG in 0.1 mol L-1 sodium citrate, pH 5.5 and by Sep-Pak silica cartridge. Sterility was performed by the microbiology procedures and pyrogen tests by the 'in-vitro' Limulus test (LAL). The stability of both radiolabeled peptides was high even 72 hours under refrigeration. The radiochemical purities of the labeled compounds were confirmed by HPLC. Sterility and pyrogen tests were negative in all delivered vials. The efficient procedure to obtain 111In-DTPA-Oct and 177Lu-DOTATATE was confirmed in the first comparative clinical groups. The methods were validated and 46.287 GMBq of 111In-DTPA-Oct and 1,193 GBq of 177Lu-DOTATATE were distributed in 2008, to nuclear medicine services in Brazil. (author)

  8. Therapeutic Efficacy with Treatment-related Toxicities of {sup 177}Lu-labeled Bombesin Derivative for the Peptide Receptor Radiotherapy

    Lim, Jae Cheong; Cho, Eun Ha; Lee, So Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    The gastrin-releasing peptide receptor (GRPR) has been shown to be overexpressed in many human tumours, including breast cancer, prostate cancer, small cell lung cancer, ovarian cancers, endometrial cancers, and gastrointestinal stromal tumors. In particular, GRPR expression is high in 83 % of invasive primary prostatic carcinomas. These results suggest that {sup 177}Lu-labeled bombesin derivative has promising characteristics as a novel nuclear medicine, especially for the treatment of GRPR over-expressing prostate tumors.

  9. Somatostatin-based radiopeptide therapy with [{sup 177}Lu-DOTA]-TOC versus [{sup 90}Y-DOTA]-TOC in neuroendocrine tumours

    Romer, A.; Seiler, D.; Brunner, P.; Ng, Q.K.T.; Mueller-Brand, J. [University Hospital Basel, Institute of Nuclear Medicine, Basel (Switzerland); Marincek, N.; Walter, M.A. [University Hospital Basel, Institute of Nuclear Medicine, Basel (Switzerland); University Hospital Bern, Institute of Nuclear Medicine, Bern (Switzerland); Koller, M.T. [University Hospital Basel, Basel Institute for Clinical Epidemiology and Biostatistics, Basel (Switzerland); Maecke, H.R. [University Hospital Basel, Division of Radiochemistry, Basel (Switzerland); Rochlitz, C. [University Hospital Basel, Department of Oncology, Basel (Switzerland); Briel, M. [University Hospital Bern, Institute of Nuclear Medicine, Bern (Switzerland); University Hospital Basel, Basel Institute for Clinical Epidemiology and Biostatistics, Basel (Switzerland); McMaster University, Department of Clinical Epidemiology and Biostatistics, Hamilton (Canada); Schindler, C. [University of Basel, Swiss Tropical and Public Health Institute, Basel (Switzerland)

    2014-02-15

    Somatostatin-based radiopeptide treatment is generally performed using the β-emitting radionuclides {sup 90}Y or {sup 177}Lu. The present study aimed at comparing benefits and harms of both therapeutic approaches. In a comparative cohort study, patients with advanced neuroendocrine tumours underwent repeated cycles of [{sup 90}Y-DOTA]-TOC or [{sup 177}Lu-DOTA]-TOC until progression of disease or permanent adverse events. Multivariable Cox regression and competing risks regression were employed to examine predictors of survival and adverse events for both treatment groups. Overall, 910 patients underwent 1,804 cycles of [{sup 90}Y-DOTA]-TOC and 141 patients underwent 259 cycles of [{sup 177}Lu-DOTA]-TOC. The median survival after [{sup 177}Lu-DOTA]-TOC and after [{sup 90}Y-DOTA]-TOC was comparable (45.5 months versus 35.9 months, hazard ratio 0.91, 95 % confidence interval 0.63-1.30, p = 0.49). Subgroup analyses revealed a significantly longer survival for [{sup 177}Lu-DOTA]-TOC over [{sup 90}Y-DOTA]-TOC in patients with low tumour uptake, solitary lesions and extra-hepatic lesions. The rate of severe transient haematotoxicities was lower after [{sup 177}Lu-DOTA]-TOC treatment (1.4 vs 10.1 %, p = 0.001), while the rate of severe permanent renal toxicities was similar in both treatment groups (9.2 vs 7.8 %, p = 0.32). The present results revealed no difference in median overall survival after [{sup 177}Lu-DOTA]-TOC and [{sup 90}Y-DOTA]-TOC. Furthermore, [{sup 177}Lu-DOTA]-TOC was less haematotoxic than [{sup 90}Y-DOTA]-TOC. (orig.)

  10. {sup 177}Lu-DOTATATE therapy in patients with neuroendocrine tumours: 5 years' experience from a tertiary cancer care centre in India

    Danthala, Madhav; Raghavendra Rao, M. [HCG Oncology Hospitals, Bangalore, Karnataka (India); Kallur, K.G.; Prashant, G.R.; Rajkumar, K. [HCG Oncology Hospitals, Department of Nuclear Medicine, Bangalore, Karnataka (India)

    2014-07-15

    The choice of an appropriate treatment option in patients with inoperable or metastatic neuroendocrine tumours (NETs) is limited, and approximately 50 % of patients have advanced NET at diagnosis, and 65 % die within 5 years. Treatment with {sup 177}Lu-DOTATATE ({sup 177}Lu-[DOTA{sup 0},Tyr{sup 3}] octreotate) is a promising new option in the treatment of metastatic NETs. Patients with metastatic NET who underwent {sup 177}Lu-DOTATATE during the period 2009 to 2013 were included in this retrospective study. Follow-up imaging studies including a {sup 68}Ga-DOTANOC PET/CT scan and a posttherapy {sup 177}Lu-DOTATATE scan were compared with baseline imaging to determine response to treatment. Progression-free survival (PFS) was calculated using the Kaplan-Meier method and Cox regression analysis was also done. Ten patients (25 %) had a minimal response, 13 (32.5 %) had a partial response and 9 (22.5 %) had stable disease. Progressive disease was seen in 8 patients (20 %), including 6 patients who died during or after the treatment period. The estimated mean PFS in those who received one or two cycles of {sup 177}Lu-DOTATATE was 8.3 months (95 % CI 6.2 to 10.3 months) compared to an estimated mean PFS of 45.6 months (95 % CI 40.9 to 50.2 months) in those who received more than two cycles of {sup 177}Lu-DOTATATE (log-rank Mantel-Cox Χ {sup 2} = 8.01, p = 0.005). Our study showed that treatment with {sup 177}Lu-DOTATATE should be considered in the management of NETs, considering the limited success of alternative treatment modalities. Treatment response and PFS is determined primarily by the dose delivered and best results are obtained when more than two cycles of {sup 177}Lu-DOTATATE are given, with careful monitoring for possible side effects. (orig.)

  11. Anti-CD45 Radioimmunotherapy with 90Y but Not 177Lu Is Effective Treatment in a Syngeneic Murine Leukemia Model

    Orozco, Johnnie J.; Ethan R. Balkin; Gooley, Ted A.; Kenoyer, Aimee; Hamlin, Donald K.; Wilbur, D. Scott; Fisher, Darrell R.; Hylarides, Mark D.; Shadman, Mazyar; Green, Damian J.; Gopal, Ajay K.; Press, Oliver W.; Pagel, John M.

    2014-01-01

    Radioimmunotherapy (RIT) for treatment of hematologic malignancies has primarily employed monoclonal antibodies (Ab) labeled with 131I or 90Y which have limitations, and alternative radionuclides are needed to facilitate wider adoption of RIT. We therefore compared the relative therapeutic efficacy and toxicity of anti-CD45 RIT employing 90Y and 177Lu in a syngeneic, disseminated murine myeloid leukemia (B6SJLF1/J) model. Biodistribution studies showed that both 90Y- and 177Lu-anti-murine CD4...

  12. Labeling procedures for the preparation of 188Re- DMSA(V)

    188Re has received a lot of attention in the past decade, due to its favorable nuclear characteristics [t1/2 16.9 h, Eβmax 2.12 MeV and Eγ 155 keV (15%) suitable for imaging], including the fact that it is carrier-free and can be obtained cost-effectively through the generator 188W-188Re. Besides the therapeutic usefulness of 188Re, the emission of the 155 keV gamma photon is an added advantage since the biodistribution of 188Re-labeled agents can be evaluated in vivo with a gamma camera. Biodistribution studies of 188Re-DMSA(V) have shown that its general pharmacokinetic properties are similar to that of 99mTc-DMSA(V), so this agent could be used for targeted radiotherapy of the same tumors, i.e., medullary thyroid carcinoma, bone metastases, soft tissue, head and neck tumors. The aim of this work is to evaluate two labeling procedures for the preparation of 188Re- DMSA(V). 188Re-DMSA(V) was prepared by two methods. The first method was prepared using a commercial kit of DMSA(III) for labeling with 99mTc, at high temperature (100 deg C). The second method was prepared in a vial containing 2.5 mg of DMSA, 1.00 mg of SnCl2.2H2O and 30 mg of sodium oxalate, in a total volume of 1.1 mL. The pH was adjusted to 5 with 37% HCl. After labeling the solution was stirred and incubated for 15 min at room temperature. The radiochemical purity was determined using TLC-SG developed with two different solvent systems. Preliminary results for both methods of labeling 188Re-DMSA(V) showed that the labeling yield was >90%. (author)

  13. Production of glass microspheres comprising 90Y and 177Lu for treating of hepatic tumors with SPECT imaging capabilities

    Our objective was to determine if glass microspheres impregnated with two radionuclides,90Y as source of therapeutic beta emissions and 177Lu as source of diagnostic gamma emissions can be useful for SPECT imaging during or after application of the 90Y microspheres for treating of hepatic tumors. The glass-based microspheres labeled with 89Y and lutetium (YAS (Lu)) or 89Y and ytterbium (YAS (Yb)) were prepared by the sol-gel process where sol droplets directly were formed to gel microspheres. Results of the neutron activation indicate that such a combination of glass, microspheres allow bio-distribution studies by SPECT imaging with high resolution. - Highlights: → A radioactive microsphere composed of glass was impregnated with two radionuclide 90Y and 177Lu. 177Lu is as a dopant for diagnostic gamma emissions. → The glass-based microspheres labeled with 89Y and lutetium (YAS (Lu)) or 89Y and ytterbium (YAS (Yb)) were prepared by the sol-gel process where gel microspheres directly were formed from sol droplets. → After neutron activation, such a combination of glass, allows SPECT imaging so bio-distribution is possible with better resolution.

  14. Biokinetics and dosimetry with 177Lu-DOTA-TATE in athymic mice with induced pancreatic malignant tumours

    Rodríguez-Cortés, J.; de Murphy, C. Arteaga; Ferro-Flores, Ge; Pedraza-López, M.; Murphy-Stack, E.

    Malignant pancreatic tumours induced in athymic mice are a good model for peptide receptor targeted radiotherapy. The objective of this research was to determine biokinetic parameters in mice, in order to estimate the induced pancreatic tumour absorbed doses and to evaluate an `in house' 177Lu-DOTA-TATE radiopharmaceutical as part of preclinical studies for targeted therapy in humans. AR42J murine pancreas cancer cells expressing somatostatin receptors, were implanted in athymic mice (nD22) to obtain biokinetic and dosimetric data of 177Lu-DOTA-TATE. The mean tumour uptake 2 h post injection was 14.76±1.9% I.A./g; kidney and pancreas uptake, at the same time, were 7.27±1.1% I.A./g (1.71±0.90%/organ) and 4.20±0.98% I.A./g (0.42±0.03%/organ), respectively. The mean absorbed dose to tumour, kidney and pancreas was 0.58±0.02 Gy/MBq; 0.23±0.01 Gy/MBq and 0.14±0.01 Gy/MBq, respectively. These studies justify further dosimetric estimations to ensure that 177Lu-DOTA-TATE will act as expected in humans.

  15. Targeted radiotherapy with {sup 177} Lu-DOTA-TATE in athymic mice with induced pancreatic malignant tumours

    Rodriguez C, J.; Murphy, C.A. de; Pedraza L, M. [Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Vasco de Quiroga No. 15, 14000 Mexico D.F. (Mexico); Ferro F, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Murphy S, E. [Hospital Santelena, 06000 Mexico D.F. (Mexico)

    2006-07-01

    Malignant pancreas tumours induced in athymic mice are a good model for peptide receptor targeted radiotherapy. The objective of this research was to estimate pancreatic tumour absorbed radiation doses after administration of {sup 177}Lu-DOTA-TATE in mice as a therapeutic radiopharmaceutical that could be used in humans. AR42J murine pancreas cancer cells expressing somatostatin receptors, were implanted in athymic mice (n=18) to obtain the {sup 177}Lu-DOTA-TATE biokinetics and dosimetry. To estimate its therapeutic efficacy 87 MBq were injected in a tail vein of 3 mice and 19 days p.i. there were a partial relapse. There was an epithelial and sarcoma mixed tumour in the kidneys of mouse III. The absorbed dose to tumour, kidney and pancreas was 50.5 {+-} 7.2 Gy, 17.5 {+-} 2.5 Gy and 12.6 {+-} 2.3 Gy respectively. These studies justify further therapeutic and dosimetry estimations to ensure that {sup 177}Lu-DOTA-TATE will act as expected in man considering its kidney radiotoxicity. (Author)

  16. Biokinetic and dosimetric study of a locally produced kit 177Lu-EDTMP for use as a pain palliative agent

    Bone-seeking radiopharmaceuticals like the ethylenediamine tetramethylene phosphonic acid (EDTMP) labeled with β--emitting radioisotopes have demonstrated their efficacy in the palliative treatment of skeletal metastasis. A biokinetic and dosimetric study of 177Lu-EDTMP in NIH mice was performed. The results obtained were extrapolated to human. We estimate the absorbed doses in organs for two models: an adult male and an adult female. 177Lu-EDTMP has a selective uptake in bone, a rapid elimination from blood and negligible uptake in non-skeletal tissues. The estimated dose in bone is between 14.7-15.3 cGy/mCi for men and between 19.6-20.4 cGy/mCi for women. Bone marrow toxicity represents the limiting factor in this kind of therapy, and to avoid exceed the maximum dose it can tolerate (200 cGy), it was found that the maximum safe activity of 177Lu-EDTMP to be injected to male (73.9 kg), corresponds to a value of 1.01 mCi/kg and a value of 1.25 mCi/kg for female (56.9 kg)

  17. Pharmacokinetic digital phantoms for accuracy assessment of image-based dosimetry in 177Lu-DOTATATE peptide receptor radionuclide therapy

    Patient-specific image-based dosimetry is considered to be a useful tool to limit toxicity associated with peptide receptor radionuclide therapy (PRRT). To facilitate the establishment and reliability of absorbed-dose response relationships, it is essential to assess the accuracy of dosimetry in clinically realistic scenarios. To this end, we developed pharmacokinetic digital phantoms corresponding to patients treated with 177Lu-DOTATATE. Three individual voxel phantoms from the XCAT population were generated and assigned a dynamic activity distribution based on a compartment model for 177Lu-DOTATATE, designed specifically for this purpose. The compartment model was fitted to time-activity data from 10 patients, primarily acquired using quantitative scintillation camera imaging. S values for all phantom source-target combinations were calculated based on Monte-Carlo simulations. Combining the S values and time-activity curves, reference values of the absorbed dose to the phantom kidneys, liver, spleen, tumours and whole-body were calculated. The phantoms were used in a virtual dosimetry study, using Monte-Carlo simulated gamma-camera images and conventional methods for absorbed-dose calculations. The characteristics of the SPECT and WB planar images were found to well represent those of real patient images, capturing the difficulties present in image-based dosimetry. The phantoms are expected to be useful for further studies and optimisation of clinical dosimetry in 177Lu PRRT. (paper)

  18. Pharmacokinetic digital phantoms for accuracy assessment of image-based dosimetry in 177Lu-DOTATATE peptide receptor radionuclide therapy

    Brolin, Gustav; Gustafsson, Johan; Ljungberg, Michael; Sjögreen Gleisner, Katarina

    2015-08-01

    Patient-specific image-based dosimetry is considered to be a useful tool to limit toxicity associated with peptide receptor radionuclide therapy (PRRT). To facilitate the establishment and reliability of absorbed-dose response relationships, it is essential to assess the accuracy of dosimetry in clinically realistic scenarios. To this end, we developed pharmacokinetic digital phantoms corresponding to patients treated with 177Lu-DOTATATE. Three individual voxel phantoms from the XCAT population were generated and assigned a dynamic activity distribution based on a compartment model for 177Lu-DOTATATE, designed specifically for this purpose. The compartment model was fitted to time-activity data from 10 patients, primarily acquired using quantitative scintillation camera imaging. S values for all phantom source-target combinations were calculated based on Monte-Carlo simulations. Combining the S values and time-activity curves, reference values of the absorbed dose to the phantom kidneys, liver, spleen, tumours and whole-body were calculated. The phantoms were used in a virtual dosimetry study, using Monte-Carlo simulated gamma-camera images and conventional methods for absorbed-dose calculations. The characteristics of the SPECT and WB planar images were found to well represent those of real patient images, capturing the difficulties present in image-based dosimetry. The phantoms are expected to be useful for further studies and optimisation of clinical dosimetry in 177Lu PRRT.

  19. Report on the 1. research coordination meeting on 'Development of therapeutic radiopharmaceuticals based on 177Lu for radionuclide therapy'

    Radionuclide therapy (RNT) employing radiopharmaceuticals labelled with emitting radionuclides is fast emerging as an important part of nuclear medicine. Radionuclide therapy is effectively utilized for bone pain palliation, thus providing significant improvement in quality of life of patients suffering from pain resulting from bone metastasis. Targeting primary diseases by using specific carrier molecules labelled with radionuclides is also widely investigated and efficacious products have been emerging for the treatment of Lymphoma and Neuroendocrine tumours. In order to ensure the wider use of radiopharmaceuticals, it is essential to carefully consider the choice of radionuclides that together with the carrier molecules will give suitable pharmacokinetic properties and therapeutic efficacy. The criteria for the selection of a radionuclide for radiotherapy are suitable decay characteristics and amenable chemistry. However, the practical considerations in selecting a radionuclide for targeted therapy are availability in high radionuclidic purity as well as high specific activity and low production cost and comfortable delivery logistics. 177Lu is one of the isotopes emerging as a clear choice for therapy. Worldwide, the isotope is under investigation for approximately 30 different clinical applications, including treatment of colon cancer, metastatic bone cancer, non-Hodgkin's lymphoma, and lung cancer. 177Lu decays with a half-life of 6.71 d by emission of particles with Emax of 497 keV (78.6%), 384 keV (9.1%) and 176 keV (12.2%). It also emits photons of 113 keV (6.4%) and 208 keV (11%), that are ideally suited for imaging the in-vivo localization and dosimetric calculations applying a gamma camera. The physical half-life of 177Lu is comparable to that of 131I, the most widely used therapeutic radionuclide. The long halflife of 177Lu provides logistic advantage for production, QA/QC of the products as well as feasibility to supply the products to places far away

  20. Complexes of low energy beta emitters {sup 47}Sc and {sup 177}Lu with zoledronic acid for bone pain therapy

    Majkowska, Agnieszka [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland)], E-mail: a.majkowska@ichtj.waw.pl; Neves, Maria; Antunes, Ines [Instituto Tecnologico e Nuclear, Estrada Nacional 10, 2686-953 Sacavem (Portugal); Bilewicz, Aleksander [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland)

    2009-01-15

    Targeted radiopharmaceuticals have been mostly developed to visualize and/or treat oncologic diseases. In targeted radiotherapy radionuclide selection is a key issue, because the radionuclide should provide the appropriate radiation absorbed dose, matching the desirable biologic effect, but at the same time it should preclude irradiation of surrounding healthy tissues. Among the last generation of bisphosphonates with cyclic side chains, zoledronic acid is the most potent bisphosphonate, described till now, which inhibits bone resorption. In this paper, we describe the synthesis, properties and hydroxyapatite binding of zoledronic acid labeled with two low energy beta emitters, {sup 47}Sc and {sup 177}Lu. Radiochemicals labeled with low energy electron emitters are preferred, because they deliver both a therapeutic dose to the bone and spare the bone marrow. Hydroxyapatite adsorption experiments have shown that the binding values obtained with complexes of zoledronic acid labeled with {sup 46}Sc and {sup 177}Lu are much higher than those of bisphosphonates labeled with {sup 153}Sm and {sup 166}Ho. Hence, complexes of zoledronic acid with either {sup 46}Sc or {sup 177}Lu seems to be a promising radiopharmaceutical for bone pain therapy.

  1. [177Lu-DOTA]0-D-Phe1-Tyr3-Octreotide (177Lu-DOTATOC) For Peptide Receptor Radiotherapy in Patients with Advanced Neuroendocrine Tumours: A Phase-II Study

    Baum, Richard P.; Kluge, Andreas W.; Kulkarni, Harshad; Schorr-Neufing, Ulrike; Niepsch, Karin; Bitterlich, Norman; van Echteld, Cees J.A.

    2016-01-01

    Purpose: To characterise efficacy and safety of 177Lu-DOTATOC as agent for peptide receptor radiotherapy (PRRT) of advanced neuroendocrine tumours (NET). Patients and methods: Fifty-six subjects with metastasized and progressive NET (50% gastroenteral, 26.8% pancreatic, 23.2% other primary sites) treated consecutively with 177Lu-DOTATOC were analysed retrospectively. Subjects were administered 177Lu-DOTATOC (mean 2.1 cycles; range 1-4) as 7.0GBq (median) doses at three-monthly intervals. Efficacy was analysed using CT and/or MRI according to RECIST 1.1 criteria and results were stratified for the number of administered cycles and the primary tumour origin. Results: In the total NET population (A), median progression-free (PFS) and overall survival (OS) were 17.4 and 34.2 months, respectively, assessed in a follow-up time (mean ± SD) of 16.1 ± 12.4 months. In patients receiving more than one cycle, mean follow-up time was 22.4 ± 11.0 months for all NETs (B) and PFS was 32.0 months for all NETs (B), 34.5 months for GEP-NET (C), and 11.9 months for other NETs (D). Objective response rates (Complete/Partial Responses) were 33.9%, 40.6%, 54.2%, and 0% for A, B, C, and D groups, respectively, while disease control rates in the same were 66.1%, 93.8%, 100%, and 75%. Complete responses (16.1%, 18.8% and 25.0% for groups A, B and C) were high, 78% of which were maintained throughout the follow up. There were no serious adverse events. One case of self-limiting grade 3 myelotoxicity was reported. Although 20% of patients had mild renal insufficiency at baseline, there was no evidence of exacerbated or de novo renal toxicity after treatment. Conclusion: 177Lu-DOTATOC is a novel agent for PRRT with major potential to induce objective tumour responses and sustained disease control in progressive neuroendocrine tumours, even when administered in moderate activities. The observed safety profile suggests a particularly favourable therapeutic index, including in patients with

  2. Intracoronary radionuclide therapy with liquid 188Re-filled balloons; radiopharmaceutical and dosimetric studies

    Percutaneous transluminal coronary angioplasty associated with radioactive liquid-filled balloons has demonstrated to be useful to inhibit the growth of neo intimal tissue. The present study pursued optimizing the relation risk/benefit during a procedure of brachytherapy with 188Re associated to angioplasty. Since the possibility of balloon rupture exists, to increase the security during the treatment different agents such as 188Re-DTPA, 188Re-Citrate and 188Re-EC vs 188ReO4 were evaluated. Dosimetric studies using Mirdose 3, after iv injection to Wistar rats, evaluation of a number of safety requirements in order to estimate radiation dose delivered to operating personnel and absorbed doses estimated by Monte Carlo method (PENELOPE). It is a safe procedure, both for the patient and the working staff; in case of ballon rupture the use of the above mentioned radiopharmaceuticals increases its security. 188Reβ emitor achieves a local dosis, diminishing the dose in healthy tissue (au)

  3. The challenges of treating paraganglioma patients with {sup 177}Lu-DOTATATE PRRT: Catecholamine crises, tumor lysis syndrome and the need for modification of treatment protocols

    Makis, William; Mccann, Karey; Mcewan, Alexander J. B. [Dept. of Diagnostic Imaging, Cross Cancer Institute, Alberta (China)

    2015-09-15

    A high percentage of paragangliomas express somatostatin receptors that can be utilized for targeted radioisotope therapy. The aim of this study was to describe and discuss the challenges of treating these tumors with {sup 177}Lu-[DOTA0,Tyr3]octreotate (DOTATATE) radioisotope therapy using established protocols. Three paraganglioma patients were treated with 4–5 cycles of {sup 177}Lu-DOTATATE and were evaluated for side effects and response to therapy. Two of the three patients developed severe adverse reactions following their first {sup 177}Lu-DOTATATE treatment. One patient developed a catecholamine crisis and tumor lysis syndrome within hours of treatment, requiring intensive care unit (ICU) support, and another developed a catecholamine crisis 3 days after treatment, requiring hospitalization. The treatment protocols at our institution were subsequently modified by increasing the radioisotope infusion time from 15 to 30 min, as recommended in the literature, to 2–4 h and by reducing the administered dose of {sup 177}Lu-DOTATATE. Subsequent {sup 177}Lu-DOTATATE treatments utilizing the modified protocols were well tolerated, and response to therapy was achieved in all three patients, resulting in significantly improved quality of life. {sup 177}Lu-DOTATATE is an exciting new therapeutic option in the management of paragangliomas; however, current treatment protocols described in the literature may need to be modified by lengthening the infusion time and/or lowering the initial treatment dose to prevent or reduce the severity of adverse reactions.

  4. The challenges of treating paraganglioma patients with 177Lu-DOTATATE PRRT: Catecholamine crises, tumor lysis syndrome and the need for modification of treatment protocols

    A high percentage of paragangliomas express somatostatin receptors that can be utilized for targeted radioisotope therapy. The aim of this study was to describe and discuss the challenges of treating these tumors with 177Lu-[DOTA0,Tyr3]octreotate (DOTATATE) radioisotope therapy using established protocols. Three paraganglioma patients were treated with 4–5 cycles of 177Lu-DOTATATE and were evaluated for side effects and response to therapy. Two of the three patients developed severe adverse reactions following their first 177Lu-DOTATATE treatment. One patient developed a catecholamine crisis and tumor lysis syndrome within hours of treatment, requiring intensive care unit (ICU) support, and another developed a catecholamine crisis 3 days after treatment, requiring hospitalization. The treatment protocols at our institution were subsequently modified by increasing the radioisotope infusion time from 15 to 30 min, as recommended in the literature, to 2–4 h and by reducing the administered dose of 177Lu-DOTATATE. Subsequent 177Lu-DOTATATE treatments utilizing the modified protocols were well tolerated, and response to therapy was achieved in all three patients, resulting in significantly improved quality of life. 177Lu-DOTATATE is an exciting new therapeutic option in the management of paragangliomas; however, current treatment protocols described in the literature may need to be modified by lengthening the infusion time and/or lowering the initial treatment dose to prevent or reduce the severity of adverse reactions

  5. External beam radiotherapy synergizes 188Re-liposome against human esophageal cancer xenograft and modulates 188Re-liposome pharmacokinetics

    Chang CH

    2015-05-01

    Full Text Available Chih-Hsien Chang,1,2 Shin-Yi Liu,3 Chih-Wen Chi,3 Hsiang-Lin Yu,1 Tsui-Jung Chang,1 Tung-Hu Tsai,4 Te-Wei Lee,1 Yu-Jen Chen3–5 1Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan; 2Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 3Department of Medical Research MacKay Memorial Hospital, 4Institute of Traditional Medicine, National Yang-Ming University, 5Department of Radiation Oncology, MacKay Memorial Hospital, Taipei, Taiwan Abstract: External beam radiotherapy (EBRT treats gross tumors and local microscopic diseases. Radionuclide therapy by radioisotopes can eradicate tumors systemically. Rhenium 188 (188Re-liposome, a nanoparticle undergoing clinical trials, emits gamma rays for imaging validation and beta rays for therapy, with biodistribution profiles preferential to tumors. We designed a combinatory treatment and examined its effects on human esophageal cancer xenografts, a malignancy with potential treatment resistance and poor prognosis. Human esophageal cancer cell lines BE-3 (adenocarcinoma and CE81T/VGH (squamous cell carcinoma were implanted and compared. The radiochemical purity of 188Re-liposome exceeded 95%. Molecular imaging by NanoSPECT/CT showed that BE-3, but not CE81T/VGH, xenografts could uptake the 188Re-liposome. The combination of EBRT and 188Re-liposome inhibited tumor regrowth greater than each treatment alone, as the tumor growth inhibition rate was 30% with EBRT, 25% with 188Re-liposome, and 53% with the combination treatment at 21 days postinjection. Combinatory treatment had no additive adverse effects and significant biological toxicities on white blood cell counts, body weight, or liver and renal functions. EBRT significantly enhanced the excretion of 188Re-liposome into feces and urine. In conclusion, the combination of EBRT with 188Re-liposome might be a potential treatment modality for esophageal cancer. Keywords: Radionuclide

  6. Imaging, Autoradiography, and Biodistribution of 188Re-Labeled PEGylated Nanoliposome in Orthotopic Glioma Bearing Rat Model

    Huang, Feng-Yun J.; LEE, TE-WEI; Kao, Chih-Hao K.; Chang, Chih-Hsien; Zhang, Xiaoning; Lee, Wan-Yu; Chen, Wan-Jou; Wang, Shu-Chi; Lo, Jem-Mau

    2011-01-01

    The 188Re-labeled pegylated nanoliposome (abbreviated as 188Re-Liposome) was prepared and evaluated for its potential as a theragnostic agent for glioma. 188Re-BMEDA complex was loaded into the pegylated liposome core with pH 5.5 ammonium sulfate gradient to produce 188Re-Liposome. Orthotopic Fischer344/F98 glioma tumor-bearing rats were prepared and intravenously injected with 188Re-Liposome. Biodistribution, pharmacokinetic study, autoradiography (ARG), histopathology, and nano-SPECT/CT ima...

  7. Comparative studies of antibody anti-CD20 labeled with {sup 188}Re; Estudo comparativo da marcacao do anticorpo anti-CD20 com {sup 188}Re

    Dias, Carla Roberta de Barros Rodrigues

    2010-07-01

    Nuclear Medicine is an unique and important modality in oncology and the development of new tumor-targeted radiopharmaceuticals for both diagnosis and therapy is an area of interest for researchers. Rituximab (RTX) is a quimeric monoclonal antibody (mAb) (IgG 1) that specifically binds to CD20 antigen with high affinity and has been successfully used for the treatment of Non-Hodgkin Lymphoma (NHL) of cell B. The CD20 antigen is expressed over more than 90% of cell B NHL. Technetium-99m ({sup 99m}Tc) and rhenium-188 ({sup 188}Re) are an attractive radionuclide pair for clinical use due to their favorable decay properties for diagnosis ({sup 99m}Tc: T{sub 1/2} = 6 h, {gamma} radiation = 140 keV) and therapy ({sup 188}Re: T{sub 1/2} = 17 h, maximum {beta} energy = 2.12 MeV) and to their availability in the form of {sup 99}Mo/{sup 99}mTc and {sup 188}W/{sup 188}Re generators. The radionuclides can be conjugated to mAb using similar chemical procedures. The aim of this work was to study the labeling of anti-CD20 mAb (RTX) with {sup 188}Re using two techniques: the direct labeling method [{sup 188}Re(V)] and the labeling method via the carbonyl nucleus [{sup 188}Re(I)]. Besides the quality control, the radiolabeled mAb was submitted to in vivo, in vitro and ex vivo biological studies. For the direct labeling, RTX was reducing by incubation with 2-mercaptoethanol for generating sulphydryl groups (-SH) and further labeled with {sup 188}Re(V), in a study of several parameters in order to reach an optimized formulation. The labeling via the carbonyl nucleus both {sup 99}mTc and {sup 188}Re were employed through 2 different procedures: (1) labeling of intact RTX with {sup 99}mTc(I) and (2) reduced RTX (RTX{sub red}) labeled with {sup 99}mTc(I)/{sup 188}Re(I). Also a parameter study was performed to obtain an optimized formulation. The quality control method for evaluating the radiochemical purity showed a good labeling yield (93%) for the direct method. The labeling method

  8. Dosimetry for {sup 177}Lu-DKFZ-PSMA-617: a new radiopharmaceutical for the treatment of metastatic prostate cancer

    Delker, Andreas; Fendler, Wolfgang Peter; Brunegraf, Anika; Gosewisch, Astrid; Gildehaus, Franz Josef; Bartenstein, Peter; Boening, Guido [Ludwig-Maximilians-University of Munich, Department of Nuclear Medicine, Munich (Germany); Kratochwil, Clemens; Haberkorn, Uwe [Heidelberg University Hospital, Department for Nuclear Medicine, Heidelberg (Germany); Tritschler, Stefan; Stief, Christian Georg [Ludwig-Maximilians-University of Munich, Department of Urology, Munich (Germany); Kopka, Klaus [German Cancer Research Center (dkfz), Division of Radiopharmaceutical Chemistry, Heidelberg (Germany)

    2016-01-15

    Dosimetry is critical to achieve the optimal therapeutic effect of radioligand therapy (RLT) with limited side effects. Our aim was to perform image-based absorbed dose calculation for the new PSMA ligand {sup 177}Lu-DKFZ-PSMA-617 in support of its use for the treatment of metastatic prostate cancer. Whole-body planar images and SPECT/CT images of the abdomen were acquired in five patients (mean age 68 years) for during two treatment cycles at approximately 1, 24, 48 and 72 h after administration of 3.6 GBq (range 3.4 to 3.9 GBq) {sup 177}Lu-DKFZ-PSMA-617. Quantitative 3D SPECT OSEM reconstruction was performed with corrections for photon scatter, photon attenuation and detector blurring. A camera-specific calibration factor derived from phantom measurements was used for quantitation. Absorbed doses were calculated for various organs from the images using a combination of linear approximation, exponential fit, and target-specific S values, in accordance with the MIRD scheme. Absorbed doses to bone marrow were estimated from planar and SPECT images and with consideration of the blood sampling method according to the EANM guidelines. The average (± SD) absorbed doses per cycle were 2.2 ± 0.6 Gy for the kidneys (0.6 Gy/GBq), 5.1 ± 1.8 Gy for the salivary glands (1.4 Gy/GBq), 0.4 ± 0.2 Gy for the liver (0.1 Gy/GBq), 0.4 ± 0.1 Gy for the spleen (0.1 Gy/GBq), and 44 ± 19 mGy for the bone marrow (0.012 Gy/GBq). The organ absorbed doses did not differ significantly between cycles. The critical absorbed dose reported for the kidneys (23 Gy) was not reached in any patient. At 24 h there was increased uptake in the colon with 50 - 70 % overlap to the kidneys on planar images. Absorbed doses for tumour lesions ranged between 1.2 and 47.5 Gy (13.1 Gy/GBq) per cycle. The salivary glands and kidneys showed high, but not critical, absorbed doses after RLT with {sup 177}Lu-DKFZ-PSMA-617. We suggest that {sup 177}Lu-DKFZ-PSMA-617 is suitable for radiotherapy, offering tumour

  9. Evaluation of the therapeutic efficacy and radiotoxicity of the conjugates {sup 177}Lu-DOTA-E-c(RGDfK){sub 2} and {sup 177}Lu-DOTA-GGC-AuNP-c[RGDfk(C)] in a murine model and their relationship with the inhibition of the angiogenic factors VEGF and HIF-1α; Evaluacion de la eficacia terapeutica y radiotoxicidad de los conjugados {sup 177}Lu-DOTA-E-c(RGDfK){sub 2} y {sup 177}Lu-DOTA-GGC-AuNP-c[RGDfK(C)] en un modelo murino y su relacion con la inhibicion de los factores angiogenicos VEGF y HIF-1α

    Vilchis J, A.

    2013-07-01

    Molecular targeting therapy has become a relevant therapeutic strategy for cancer. The principle that peptide receptors can be used successfully for in vivo targeting of human cancers has been proven, and radiolabeled peptides have been demonstrated to be effective in patients with malignant tumors. Peptides based on the cyclic Arg-Gly-Asp (RGD) sequence have been designed to antagonize the function of α(v)β(3) integrin, thereby inhibiting angio genesis. The conjugation of RGD peptides to radiolabeled gold nanoparticles (AuNP) produces biocompatible and stable m ultimeric systems with target-specific molecular recognition. The aim of this research was to evaluate the therapeutic response of {sup 177}Lu-AuNP-RGD in athymic mice bearing α(v)β(3)-integrin-positive C6 gliomas and compare with that of {sup 177}Lu-AuNP or {sup 177}Lu-RGD. The radiation absorbed dose, metabolic activity (SUV, [18F]fluor-deoxy-glucose-micro PET/CT), renal radiotoxicity, renal and tumoral histological characteristics as well as tumoral VEGF and HIF-1? gene expression (by realtime polymerase chain reaction) following treatment with {sup 177}Lu-AuNP-RGD, {sup 177}Lu-AuNP or {sup 177}Lu-RGD were assessed. Of the radiopharmaceuticals evaluated, {sup 177}Lu-AuNP-RGD delivered the highest tumor radiation absorbed dose (63.8 ± 7.9 Gy) vs other treatments. These results correlated with the observed therapeutic response, in which {sup 177}Lu-AuNP-RGD significantly (p<0.05) reduced tumor progression, tumor metabolic activity, intratumoral vessels and VEGF gene expression compared to the other radiopharmaceuticals. This was consequence of high tumor retention and a combination of molecular targeting therapy (m ultimeric RGD system) and radiotherapy ({sup 177}Lu). There was a low uptake in non-target organs and no induction of renal toxicity. {sup 177}Lu-AuNP-RGD demonstrates properties suitable for use as an agent for molecular targeting radiotherapy. (Author)

  10. Evaluation of 188Re-MAG2-RGD-bombesin for potential prostate cancer therapy

    Glu-RGD-bombesin (RGD-BBN) is a heterodimeric peptide that contains motifs recognizing both integrin αvβ3 and gastrin releasing peptide receptor (GRPR). We evaluated here 188Re (t1/2 = 16.9 h) labeled RGD-BBN as a potential agent for radionuclide therapy of prostate cancer. RGD-BBN was conjugated with S-benzoylmercaptoacetylglycylglycyl (MAG2), and then labeled with 99mTc or 188Re, respectively. The dual-receptor binding affinity of MAG2-RGD-BBN was investigated by a radioligand competition binding assay. Biodistribution study of 188Re-MAG2-RGD-BBN was carried out in normal BALB/c mice and PC-3 human prostate tumor-bearing nude mice. Gamma imaging studies were performed in PC-3 tumor-bearing nude mice. Biodistribution in normal mice showed that both 99mTc and 188Re-labeled MAG2-RGD-BBN possessed high pancreas uptake due to the high GRPR expression of this organ. Gamma imaging with both 99mTc and 188Re-labeled RGD-BBN in PC-3 tumor-bearing nude mice demonstrated high tumor uptake. The PC-3 tumors were clearly visible at 1 postinjection, with high contrast to the contralateral background. The use of chelator MAG2 enables successful and high-yield 99mTc and 188Re radiolabeling of RGD-BBN with favorable tumor targeting specificity. Further optimization may allow potential clinical application of 188Re-MAG2-RGD-BBN for tumor-targeted radionuclide therapy

  11. The involvement of selected membrane transport mechanisms in the cellular uptake of 177Lu-labeled bombesin, somatostatin and gastrin analogues

    Introduction: Radiolabeled receptor-targeting peptides are a useful tool for the diagnostic imaging and radiotherapy of some malignancies. However, the retention of radioactivity in the kidney may result in renal radiotoxic injury. This study seeks to evaluate the role of endocytic receptor megalin, renal SLC influx transporters and fluid phase endocytosis (FPE) in the cellular accumulation of radiolabeled peptides. Methods: In vitro transport cellular studies using megalin ligands (RAP, albumin), fluid phase endocytosis (FPE) inhibitor rottlerin and low temperature were employed to evaluate the transport mechanisms of the peptides. Cells transfected with hOAT1 or hOCT2 were used to analyze the role of these SLC transporters. Somatostatin (177Lu-DOTA-[Tyr3]octreotate, 177Lu-DOTA-[1-Nal3]octreotide), gastrin (177Lu-DOTA-sargastrin) and bombesin (177Lu-DOTA-[Pro1,Tyr4]bombesin, 177Lu-DOTA-[Lys3]bombesin, 177Lu-PCTA-[Lys3]bombesin) analogues were involved in the study. Results: RAP, albumin and low temperature decreased the accumulation of all the studied peptides significantly. With one exception, rottlerin caused the concentration dependent inhibition of the cellular accumulation of the radiopeptides. No significant differences in the uptake of the peptides between the control cells and those transfected with hOAT1 or hOCT2 were observed. Conclusion: The study showed that active transport mechanisms are decisive for the cellular accumulation in all tested 177Lu-labeled somatostatin, gastrin and bombesin analogues. Besides receptor-mediated endocytosis by megalin, FPE participates significantly in the uptake. The tested types of renal SLC transporters are not involved in this process

  12. Dosimetric evaluation of anti-CD20 labelled with 188Re

    Radioimmunotherapy has the potential to deliver lethal radiation energy directly to malignant cells via targeting of radioisotope-conjugated monoclonal antibodies (MAbs) to specific antigens. B-cell lymphoma is a particularly good candidate for radioimmunotherapy because the disease is inherently radiosensitive, malignant cells in the blood, bone marrow, spleen and lymphonodes are accessible, and MAbs have been developed to B-cell surface antigens that do not shed or modulate. Rituximab (RTX), the human IgG1-type chimeric form of the parent murine antibody ibritumomab, is specifically targeted against CD20, a surface antigen expressed by pre-B and mature human B lymphocytes. The use of rhenium-188 from a 188W/188Re generator system represents an attractive alternative radionuclide for therapy. 188Re is produced from beta decay of the 188W parent. In addition to the emission of high-energy electrons (Eβ= 2118 keV), 188Re also decays with emission of a gamma photon with an energy of 155 keV in 15% abundance. Besides the therapeutic usefulness of 188Re, the emission of gamma photon is an added advantage since the biodistribution of 188Re-labeled antibodies can be evaluated in vivo with a gamma camera. Also, rhenium has chemical properties similar to technetium. Thus, both can be conjugated to antibodies using similar chemistry methods. The objective of this work is to prove the usefulness of this radiopharmaceutical based on dosimetric studies, that are also required by the Brazilian Regulatory Agency (ANVISA). (author)

  13. A review on the current status and production technology for 188W-188Re generator system

    The current status of 188W-188Re generator production technology were reviewed in PART 1. Main interests were given to the aspects of 188W reactor production, irradiated targets reprocessing and generator loading technologies, such as alumina type and gel type generators. In order to develop the more convenient and advanced 188W-188Re generator, further studies must be carried out to get the precise evaluation of production and burn-up cross section of 188W, the more easily realizable generator loading procedure, and also to optimize the column and generator design to compensate the deterioration of generator performance because of parent radionuclide decay. By irradiation of 186W enriched sample, 188W-188Re generator production experiments were performed to evaluate the possibility of 188W-188Re generator production using HANARO, and PART 2 describes about the experiments. The experimental results shows the possibility of practical 188W-188Re generator production using of low-specific activity 188W produced in HANARO. (author). 79 refs., 4 tabs., 26 figs

  14. In vivo examination of 188Re(I)-tricarbonyl-labeled trastuzumab to target HER2-overexpressing breast cancer

    Introduction: Trastuzumab (Herceptin), a humanized IgG1 monoclonal antibody directed against the extracellular domain of the HER2 protein, acts as an immunotherapeutic agent for HER2-overexpressing human breast cancers. Radiolabeled trastuzumab with β- or α emitters can be used as radioimmunotherapeutic agent for the similar purpose but with additional radiation effect. Methods: In this study, trastuzumab was labeled with 188Re for radioimmunotherapy of HER2/neu-positive breast cancer. 188Re(I)-tricarbonyl ion, [188Re(OH2)3(CO)3]+, was employed as a precursor for directly labeling the monoclonal antibody with 188Re. The immunoreactivity of 188Re(I)-trastuzumab was estimated by competition receptor-binding assay using HER2/neu-overexpressive BT-474 human breast cancer cells. The localization properties of 188Re(I)-trastuzumab within both tumor and normal tissues of athymic mice bearing BT-474 human breast cancer xenografts (HER2/neu-overexpressive) and similar mice bearing MCF-7 human breast cancer xenografts (HER2/neu-low expressive) were investigated. Results: When incubated with human serum albumin and histidine at 25oC, 188Re(I)-trastuzumab was found to be stable within 24 h. The IC50 of 188Re(I)-trastuzumab was found to be 22.63±4.57 nM. 188Re(I)-trastuzumab was shown to accumulate specifically in BT-474 tumor tissue in in vivo biodistribution studies. By microSPECT/CT, the image of 188Re localized BT-474 tumor was clearly visualized within 24 h. In contrast, 188Re(I)-trastuzumab uptake in HER2-low-expressing MCF-7 tumor was minimal, and the 188Re image at the localization of the tumor was dim. Conclusion: These results reveal that 188Re(I)-trastuzumab could be an appropriate radioimmunotherapeutic agent for the treatment of HER2/neu-overexpressing cancers.

  15. Monomeric, dimeric and multimeric system of RGD peptides radiolabeled with 177Lu for tumors therapy that expressing αβ integrin s

    The conjugation of peptides to gold nanoparticles (AuNPs) produces biocompatible and stable multimeric systems with target-specific molecular recognition. Peptides based on the cyclic Arg-Gly-Asp (RGD) sequence have been reported as high affinity agents for the α(v)β(3) and α(v)β(5) integrin. The aim of this research was to prepare a multimeric system of 177Lu-labeled gold nanoparticles conjugated to c[RGDfK(C)] [cyclo(Arg-Gly-Asp-Phe-Lys(Cys)] peptides and to compare the radiation absorbed dose with that of 177Lu-labeled monomeric and dimeric RGD peptides to α(v)β(3) integrin-positive U87MG tumors in mice, as well as, evaluate the in vitro potential 177Lu-AuNP-c[RGDfK(C)] as a plasmonic photothermal therapy and targeted radiotherapy system in MCF7 breast cancer cells. DOTA-GGC (1,4,7,10-tetraaza cyclododecane-N,N,N-tetraacetic-Gly-Gly-Cys) and c[RGDfK(C)] peptides were synthesized and conjugated to AuNPs by the spontaneous reaction of the thiol groups. Tem, UV-Vis, XP S, Raman and Far-IR spectroscopy techniques demonstrated that AuNPs were functionalized with the peptides. To obtain 177Lu-AuNP-c[RGDfK(C)], the 177Lu-DOTA-GGC radio peptide was first prepared and added to a solution of AuNPs followed by c[RGDfK(C)] (25 μL, 5 μM) at 18 grades C for 15 min. 177Lu-DOTA-GGC, 177Lu- DOTA-cRGDfK and 177Lu-DOTA-E-c(RGDfK)2 were prepared by adding 177LuCl3 (370 MBq) to 5 μL (1 mg/ml) of the DOTA derivative diluted with 50 μL of 1 M acetate buffer at ph 5. The mixture was incubated at 90 grades C in a block heater for 30 min. Radiochemical purity was determined by ultrafiltration and HPLC analyses. After laser irradiation, the presence of c[RGDfK(C)]-AuNP in cells caused a significant increase in the temperature of the medium (50.5 grades C, compared to 40.3 grades C without AuNPs) resulting in a significant decrease in MCF7 cell viability down to 9 %. After treatment with 177Lu-AuNP-c[RGDfK(C)], the MCF7 cell proliferation was significantly inhibited. Biokinetic

  16. Application of analytic methodologies for image quantification in neuroendocrine tumor therapy with {sup 177}Lu-DOTA

    Kubo, T.T.A.; Oliveira, S.M.V. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Marco, L.; Mamede, M., E-mail: tadeukubo@gmail.com [Instituto Nacional do Cancer, Rio de Janeiro, RJ (Brazil)

    2012-07-01

    Neuroendocrine tumors have annual incidence of 1 to 2 cases per one hundred thousand inhabitants. The {sup 177}Lu-DOTA-octreotate treatments in 3 or 4 cycles has been effective in controlling disease progression and, in some cases, promote tumor remission. To estimate radiation side effects in healthy organs, image quantification techniques have been broadcast for individualized patient dosimetry. In this paper, image data processing methods are presented to allowing comparisons between different image conjugate views, combined with attenuation correction and system sensitivity. Images were acquired 24, 72 and 192 h after administration of 74 GBq of {sup 177}Lu-DOTA using a dual-head gamma camera detection system and they were evaluated with ImageJ software. 4 female patients underwent to two cycles of treatment. The kidneys, liver and whole-body regions of interest were separately assessed by 4 techniques for counts method and 12 techniques for pixel intensity method, considering the main photopeak separately and aided by the attenuation correction map and adjacent windows to photopeak energy. The pixel intensity method was combined with mathematical correction for pixels with null value. The results obtained by the two methods were strongly correlated (r>0.9) (p<0.001). The paired t-test accepted the null hypothesis of compatibility between the two methods (with and without attenuation correction map) (p<0.05), but rejected it when the adjacent windows were combined. No significant tumor reduction (p>0.05) was found between the treatment cycles. In conclusion, the pixel intensity method is faster and allows macros, minimizing operator error, and may optimize dosimetry in tumor therapies with {sup 177}Lu-DOTA-octreotate. (author)

  17. Optimising conditions for radiolabelling of DOTA-peptides with 90Y, 111In and 177Lu at high specific activities

    DOTA-conjugated peptides, such as [DOTA0,Tyr3]octreotide (DOTATOC) and [DOTA0,Tyr3]octreotate (DOTA-tate), can be labelled with radionuclides such as 90Y, 111In and 177Lu. These radiolabelled somatostatin analogues are used for peptide receptor radionuclide therapy (PRRT). Radioligands for PRRT require high specific activities. However, although these radionuclides are produced without addition of carrier, contaminants are introduced during production and as decay products. In this study, parameters influencing the kinetics of labelling of DOTA-peptides were investigated and conditions were optimised to obtain the highest achievable specific activity. The effects of contaminants were systematically investigated, concentration dependently, in a test model mimicking conditions for labelling with minimal molar excess of DOTA-peptides over radionuclide. Kinetics of labelling of DOTA-peptides were optimal at pH 4-4.5; pH 90Y and 177Lu was completed after 20 min at 80 C, while labelling with 111In was completed after 30 min at 100 C. The effects of contaminants were systematically categorised, e.g. Cd2+ is the target and decay product of 111In, and it was found to be a strong competitor with 111In for incorporation in DOTA. In contrast, Zr4+ and Hf4+, decay products of 90Y and 177Lu, respectively, did not interfere with the incorporation of these radionuclides. The following conclusions are drawn: (a) DOTA-peptides can be radiolabelled at high specific activity; (b) reaction kinetics differ for each radionuclide; and (c) reactions can be hampered by contaminants, such as target material and decay products. (orig.)

  18. Radionuclide therapy of HER2-positive microxenografts using a 177Lu-labeled HER2-specific Affibody molecule.

    Tolmachev, Vladimir; Orlova, Anna; Pehrson, Rikard; Galli, Joakim; Baastrup, Barbro; Andersson, Karl; Sandström, Mattias; Rosik, Daniel; Carlsson, Jörgen; Lundqvist, Hans; Wennborg, Anders; Nilsson, Fredrik Y

    2007-03-15

    A radiolabeled anti-HER2 Affibody molecule (Z(HER2:342)) targets HER2-expressing xenografts with high selectivity and gives good imaging contrast. However, the small size (approximately 7 kDa) results in rapid glomerular filtration and high renal accumulation of radiometals, thus excluding targeted therapy. Here, we report that reversible binding to albumin efficiently reduces the renal excretion and uptake, enabling radiometal-based nuclide therapy. The dimeric Affibody molecule (Z(HER2:342))(2) was fused with an albumin-binding domain (ABD) conjugated with the isothiocyanate derivative of CHX-A''-DTPA and labeled with the low-energy beta-emitter (177)Lu. The obtained conjugate [CHX-A''-DTPA-ABD-(Z(HER2:342))(2)] had a dissociation constant of 18 pmol/L to HER2 and 8.2 and 31 nmol/L for human and murine albumin, respectively. The radiolabeled conjugate displayed specific binding to HER2-expressing cells and good cellular retention in vitro. In vivo, fusion with ABD enabled a 25-fold reduction of renal uptake in comparison with the nonfused dimer molecule (Z(HER2:342))(2). Furthermore, the biodistribution showed high and specific uptake of the conjugate in HER2-expressing tumors. Treatment of SKOV-3 microxenografts (high HER2 expression) with 17 or 22 MBq (177)Lu-CHX-A''-DTPA-ABD-(Z(HER2:342))(2) completely prevented formation of tumors, in contrast to mice given PBS or 22 MBq of a radiolabeled non-HER2-binding Affibody molecule. In LS174T xenografts (low HER2 expression), this treatment resulted in a small but significant increase of the survival time. Thus, fusion with ABD improved the in vivo biodistribution, and the results highlight (177)Lu-CHX-A''-DTPA-ABD-(Z(HER2:342))(2) as a candidate for treatment of disseminated tumors with a high level of HER2 expression. PMID:17363599

  19. Phase II study of radiopeptide {sup 177}Lu-octreotate and capecitabine therapy of progressive disseminated neuroendocrine tumours

    Claringbold, Phillip G. [Fremantle Hospital, Department of Oncology, Fremantle, WA (Australia); Brayshaw, Paul A.; Turner, J.H. [University of Western Australia, Department of Nuclear Medicine, Fremantle Hospital, Fremantle, WA (Australia); Price, Richard A. [Fremantle Hospital, Department of Radiology, Fremantle, WA (Australia)

    2011-02-15

    In this phase II study we investigated the safety and efficacy of combination capecitabine and {sup 177}Lu-octreotate for the treatment of disseminated, progressive, unresectable neuroendocrine tumours (NETs). Enrolled in the study were 33 patients with biopsy-proven NETs, positive {sup 111}In-octreotide scintigraphy and progressive disease measurable by CT/MRI who were to receive four cycles of 7.8 GBq {sup 177}Lu-octreotate 8-weekly, with 14 days of 1,650 mg/m{sup 2} capecitabine per day. Of the 33 patients, 25 completed four cycles. Minimal transient myelosuppression at 3-4 weeks caused grade 3 thrombocytopenia in one patient but no neutropenia. Nephrotoxicity was absent. Critical organ radiation dosimetry provided median estimates of the dose per cycle to the kidneys of 2.4 Gy and to the liver of 4.8 Gy, and showed cumulative doses all below toxic thresholds. Objective response rates (ORR) were 24% partial response (PR), 70% stable disease (SD) and 6% progressive disease. Median progression-free survival and median overall survival had not been reached at a median follow-up of 16 months (range 5-33 months). Survival at 1 and 2 years was 91% (95% CI 75-98%) and 88% (95% CI 71-96%), respectively. The addition of capecitabine radiosensitizing chemotherapy does not increase the minimal toxicity of {sup 177}Lu-octreotate radiopeptide therapy and led to an ORR of 24% PR and 70% minor response or SD in patients with progressive metastatic NETs. Tumour control and stabilization of disease was obtained in 94% of these patients. (orig.)

  20. Study of 188Re(V)-DMSA for treatment of cancer: radiolabeling and biodistribution

    The purpose of this study was to examine the radiolabeling and biodistribution of 188Re(V)-DMSA as a therapeutic cancer radiopharmaceutical. We made a DMSA kit(NaHCO3 1.5 mg, meso-2,3-dimercaptosuccinic acid 1.0 mg, L(+)-ascorbic acid 0.7 mg, SnCl2·2H2O 0.34 mg, pH 2.9) for labeling with 188Re. In this kit, 188ReO4 5 mCi/2 ml added and boiled at 100 .deg. C for 3 hr in water bath. The final pH adjusted to 7.5 with 7% NaHCO3 solution. We checked the labelling efficacy with TLC-SG(n-butanol : acetic acid : H2O= 3 : 2: 3) and examined the stability both in room temperature and in serum at 37 .deg. C. Biodistribution (1, 3, 13, 24, 48 hr) of 188Re(V)-DMSA compound was evaluated in Sarcoma 180 tumor-bearing mice. Each labeling efficiency and stability at room temperature for 48 hours was over 98% and 95%, respectively. The stability in serum were 82% (6 hr) and 85% (48 hr). Tumor uptake of 188Re(V)-DMSA in Sarcoma 180-bearing mice were 0.66±0.15% (1 hr), 0.51±0.10% (3 hr), 0.19±0.05%(24 hr) and 0.13±0.02%(48 hr). These result are consistent with those of 99mTc(V)-DMSA which were reported previously. In conclusion, 188Re(V)-DMSA may be a useful therapeutic radiopharmaceutical for treating some cancers and metastatic bone lesion

  1. Alternative chromatographic processes for no-carrier added 177Lu radioisotope separation. Part 2. The conventional column chromatographic separation combined with HPLC for high purity

    HPLC technique combined with the simple conventional column solid phase extraction (SPE) chromatography using di-(2-ethylhexyl)orthophosphoric acid (HDEHP) impregnated OASIS-HLB sorbent based SPE resins (OASIS-HDEHP ) was developed for the separation of no-carrier added (n.c.a) 177Lu from the bulk quantity of ytterbium target. This combination strategy was based on combining the advantages of the better resolution of HPLC separation of n.c.a 177Lu from the few milligram level Yb target with the high capacity of the OASISHDEHP column for the separation of 177Lu from the bulk Yb target. The production batches of several hundred mCi activity of n.c.a 177Lu radioisotope separated from 50 mg Yb target activated in a nuclear reactor of medium neutron flux (Φ = 5 x 1013 n x cm-2 x s-1) were successfully performed using this combined separation technique. With the target irradiation in a reactor of higher thermal neutron flux or with the parallel run of several separation units, several Ci-s of n.c.a 177Lu can be profitably produced on a commercial production basis. (author)

  2. Report on short-term side effects of treatments with {sup 177}Lu-octreotate in combination with capecitabine in seven patients with gastroenteropancreatic neuroendocrine tumours

    Essen, Martijn van; Kam, Boen L.; Kwekkeboom, Dik J. [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands); Krenning, Eric P. [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands); Erasmus MC, Department of Internal Medicine, Rotterdam (Netherlands); Herder, Wouter W. de; Aken, Maarten O. van [Erasmus MC, Department of Internal Medicine, Rotterdam (Netherlands)

    2008-04-15

    Treatment with the radiolabelled somatostatin analogue {sup 177}Lu-octreotate results in tumour remission in 47% of patients with gastroenteropancreatic neuroendocrine tumours. Adding capecitabine to {sup 177}Lu-octreotate, as a radio-sensitiser, may enhance these anti-tumour effects. We now present the short-term toxicity profile of this novel combination. Seven patients were treated with 7.4 GBq {sup 177}Lu-octreotate and capecitabine (1650 mg/m{sup 2} per day) for 2 weeks with an intended number of four cycles. Toxicity, and especially haematological and renal parameters, were monitored on a weekly basis for the first two cycles and 4 and 6 weeks after subsequent cycles. None of the patients had hand-foot syndrome. One patient had grade 1 stomatitis occurring after one of four cycles. Grade 3 or 4 leukopenia or neutropenia did not occur. One patient had grade 3 anaemia, but none had grade 4 anaemia. One patient had grade 2 thrombocytopenia after the fourth cycle, and one had grade 3 thrombocytopenia. Grade 4 thrombocytopenia did not occur. No significant changes in serum creatinine levels were observed. None of the patients had symptoms of cardiac ischaemia. Treatment with the combination of {sup 177}Lu-octreotate and capecitabine was feasible and safe considering acute and subacute side effects. We therefore started a randomised, controlled clinical trial to compare this combination with {sup 177}Lu-octreotate as single agent with regard to anti-tumour effects and side effects. (orig.)

  3. MIRD Pamphlet No. 26: Joint EANM/MIRD Guidelines for Quantitative 177Lu SPECT Applied for Dosimetry of Radiopharmaceutical Therapy.

    Ljungberg, Michael; Celler, Anna; Konijnenberg, Mark W; Eckerman, Keith F; Dewaraja, Yuni K; Sjögreen-Gleisner, Katarina; Bolch, Wesley E; Brill, A Bertrand; Fahey, Frederic; Fisher, Darrell R; Hobbs, Robert; Howell, Roger W; Meredith, Ruby F; Sgouros, George; Zanzonico, Pat; Bacher, Klaus; Chiesa, Carlo; Flux, Glenn; Lassmann, Michael; Strigari, Lidia; Walrand, Stephan

    2016-01-01

    The accuracy of absorbed dose calculations in personalized internal radionuclide therapy is directly related to the accuracy of the activity (or activity concentration) estimates obtained at each of the imaging time points. MIRD Pamphlet no. 23 presented a general overview of methods that are required for quantitative SPECT imaging. The present document is next in a series of isotope-specific guidelines and recommendations that follow the general information that was provided in MIRD 23. This paper focuses on (177)Lu (lutetium) and its application in radiopharmaceutical therapy. PMID:26471692

  4. Labeling procedures for the preparation of {sup 188}Re- DMSA(V)

    Brambilla, Tania P.; Osso Junior, Joao A., E-mail: taniabrambilla@yahoo.com.b, E-mail: jaosso@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    {sup 188}Re has received a lot of attention in the past decade, due to its favorable nuclear characteristics [t{sub 1/2} 16.9 h, E{sub beta}{sub max} 2.12 MeV and E{sub gamma} 155 keV (15%) suitable for imaging], including the fact that it is carrier-free and can be obtained cost-effectively through the generator {sup 188}W-{sup 188}Re. Besides the therapeutic usefulness of {sup 188}Re, the emission of the 155 keV gamma photon is an added advantage since the biodistribution of {sup 188}Re-labeled agents can be evaluated in vivo with a gamma camera. Biodistribution studies of {sup 188}Re-DMSA(V) have shown that its general pharmacokinetic properties are similar to that of {sup 99}mTc-DMSA(V), so this agent could be used for targeted radiotherapy of the same tumors, i.e., medullary thyroid carcinoma, bone metastases, soft tissue, head and neck tumors. The aim of this work is to evaluate two labeling procedures for the preparation of {sup 188}Re- DMSA(V). {sup 188}Re-DMSA(V) was prepared by two methods. The first method was prepared using a commercial kit of DMSA(III) for labeling with {sup 99m}Tc, at high temperature (100 deg C). The second method was prepared in a vial containing 2.5 mg of DMSA, 1.00 mg of SnCl{sub 2}.2H2{sub O} and 30 mg of sodium oxalate, in a total volume of 1.1 mL. The pH was adjusted to 5 with 37% HCl. After labeling the solution was stirred and incubated for 15 min at room temperature. The radiochemical purity was determined using TLC-SG developed with two different solvent systems. Preliminary results for both methods of labeling {sup 188}Re-DMSA(V) showed that the labeling yield was >90%. (author)

  5. Sequential radioimmunotherapy with 177Lu- and 211At-labeled monoclonal antibody BR96 in a syngeneic rat colon carcinoma model

    Eriksson, Sophie E; Elgström, Erika; Bäck, Tom;

    2014-01-01

    UNLABELLED: Alpha-particle emitters, such as astatine-211 (211At), are generally considered suitable for the treatment of small cell clusters due to their short path length, while beta-particle emitters, for example, Lutetium-177 (177Lu), have a longer path length and are considered better for...... small, established tumors. A combination of such radionuclides may be successful in regimens of radioimmunotherapy. In this study, rats were treated by sequential administration of first a 177Lu-labeled antibody, followed by a 211At-labeled antibody 25 days later. METHODS: Rats bearing solid colon...... carcinoma tumors were treated with 400 MBq/kg body weight 177Lu-BR96. After 25 days, three groups of animals were given either 5 or 10 MBq/kg body weight of 211At-BR96 simultaneously with or without a blocking agent reducing halogen uptake in normal tissues. Control animals were not given any 211At-BR96...

  6. Targeted radiotherapy with {sup 177} Lu-DOTA-TATE in athymic mice with induced pancreatic malignant tumours

    Murphy, M. A de; Pedraza L, M. [Department of Nuclear Medicine, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico D.F. (Mexico); Rodriguez C, J. [Faculty of Medicine, UAEM, Toluca, Estado de Mexico (Mexico); Ferro F, G. [ININ, 52045 Estado de Mexico (Mexico); Murphy S, E. [Hospital Santelena, Mexico D.F. (Mexico)

    2006-07-01

    Malignant pancreas tumours induced in athymic mice are a good model for targeted radiotherapy. The objective of this research was to estimate pancreatic tumour absorbed radiation doses and to evaluate {sup 177}Lu-DOTA-TATE as a therapeutic radiopharmaceutical that could be used in humans. AR42J murine pancreas cancer cells, which over-express somatostatin receptors, were injected in athymic mice and 20 days later the mean tumour size was 3.08 square cm (n=3). A mean of 86.3 MBq {sup 177}Lu-DOTA-TATE, was injected in a tail vein and 19 days after therapy the size of the tumours was 0.81 square cm. There was a partial relapse and after 16 days, when sacrificed, the mean tumour size was 8.28 cubic cm. An epithelial and sarcoma mixed tumour in the kidney of one treated mouse was found. The tumour of the control mouse was 8.61 cubic cm when sacrificed 14 days after tumour induction. Radiotherapy estimates to the tumours was 35.9-39.7 Gy and the tumours might have been completely reduced with a second therapy dose. These preliminary studies justify further therapeutic and dosimetry estimations to ensure that Lu-{sup 177}-DOTA-TATE will act as expected in man, considering kidney radiation. (Author)

  7. Treatment with tandem [{sup 90}Y]DOTA-TATE and [{sup 177}Lu]DOTA-TATE of neuroendocrine tumours refractory to conventional therapy

    Seregni, E.; Maccauro, M.; Chiesa, C.; Pascali, C.; Lorenzoni, A.; Bogni, A.; Coliva, A.; Bombardieri, E. [Fondazione IRCCS Istituto Nazionale Tumori, Nuclear Medicine, Milan (Italy); Mariani, L.; Vullo, S.Lo [Fondazione IRCCS Istituto Nazionale Tumori, Statistics and Biometry Unit, Milan (Italy); Mazzaferro, V. [Fondazione IRCCS Istituto Nazionale Tumori, Surgery and Liver Transplantation, Milan (Italy); De Braud, F.; Buzzoni, R. [Fondazione IRCCS Istituto Nazionale Tumori, Medical Oncology, Milan (Italy); Milione, M. [Fondazione IRCCS Istituto Nazionale Tumori, Pathology Department, Milan (Italy)

    2014-02-15

    Peptide receptor radionuclide therapy (PRRT) with radiolabelled somatostatin analogues has been demonstrated to be an effective therapeutic option in patients with disseminated neuroendocrine tumours (NET). Treatment with tandem [{sup 90}Y]DOTA-TATE and [{sup 177}Lu]DOTA-TATE may improve the efficacy of PRRT without increasing the toxicity. In a phase II study we evaluated the feasibility of combined PPRT with a high-energy beta emitter ({sup 90}Y) and a medium-energy beta/gamma emitter ({sup 177}Lu) in patients with metastatic NET refractory to conventional therapy. A group of 26 patients with metastatic NET were treated with four therapeutic cycles of alternating [{sup 177}Lu]DOTA-TATE (5.55 GBq) and [{sup 90}Y]DOTA-TATE (2.6 GBq). A dosimetric evaluation was carried out after administration of [{sup 177}Lu]DOTA-TATE to calculate the absorbed doses in healthy organs. The acute and long-term toxicities of repeated treatment were analysed. PRRT efficacy was evaluated according to RECIST. Administration of tandem [{sup 90}Y]DOTA-TATE and [{sup 177}Lu]DOTA-TATE induced objective responses in 42.3 % of patients with metastatic NET with a median progression-free survival longer than 24 months. Of patients with pretreatment carcinoid syndrome, 90 % showed a symptomatic response or a reduction in tumour-associated pain. The cumulative biologically effective doses (BED) were below the toxicity limit in the majority of patients, in the absence of renal function impairment The results of our study indicates that combined [{sup 90}Y]DOTA-TATE and [{sup 177}Lu]DOTA-TATE therapy is a feasible and effective therapeutic option in NET refractory to conventional therapy. Furthermore, the absence of kidney damage and the evaluated cumulative BEDs suggest that increasing the number of tandem administrations is an interesting approach. (orig.)

  8. Pre-Clinical Assessment of 177Lu-Labeled Trastuzumab Targeting HER2 for Treatment and Management of Cancer Patients with Disseminated Intraperitoneal Disease

    Ray, Geoffrey L.; Baidoo, Kwamena E.; Keller, Lanea M. M.; Albert, Paul S.; Brechbiel, Martin W.; Milenic, Diane E.

    2011-01-01

    Studies from this laboratory have demonstrated the potential of targeting HER2 for therapeutic and imaging applications with medically relevant radionuclides. To expand the repertoire of trastuzumab as a radioimmunoconjugate (RIC) vector, use of 177Lu was investigated. The combination of a 6.7 d half-life, lower energy β−-emissions (500 keV max; 130 keV ave), and an imagable γ-emission make 177Lu an attractive candidate for radioimmunotherapy (RIT) regimens for treatment of larger tumor burdens not possible with α-particle radiation. Radiolabeling trastuzumab-CHX-A″-DTPA with 177Lu was efficient with a specific binding of 60.8 ± 6.8% with HER2 positive SKOV-3 cells. Direct quantitation of tumor targeting and normal tissue uptake was performed with athymic mice bearing subcutaneous and intraperitoneal LS-174T xenografts; a peak tumor %ID/g of 24.70 ± 10.29 (96 h) and 31.70 ± 16.20 (72 h), respectively, was obtained. Normal tissue uptake of the RIC was minimal. Tumor targeting was also demonstrated by γ-scintigraphy. A therapy study administeringescalating doses of 177Lu-trastuzumab to mice bearing three day LS-174T i.p. xenografts established the effective therapeutic dose of i.p. administered 177Lu-trastuzumab at 375 μCi with a median survival of 124.5 d while a median survival of 10 d was noted for the control (untreated) group. In conclusion, trastuzumab radiolabeled with 177Lu has potential for treatment of disseminated, HER2 positive, peritoneal disease. PMID:22229017

  9. Pre-Clinical Assessment of 177Lu-Labeled Trastuzumab Targeting HER2 for Treatment and Management of Cancer Patients with Disseminated Intraperitoneal Disease

    Diane E. Milenic

    2011-12-01

    Full Text Available Studies from this laboratory have demonstrated the potential of targeting HER2 for therapeutic and imaging applications with medically relevant radionuclides. To expand the repertoire of trastuzumab as a radioimmunoconjugate (RIC vector, use of 177Lu was investigated. The combination of a 6.7 d half-life, lower energy β−-emissions (500 keV max; 130 keV ave, and an imagable γ-emission make 177Lu an attractive candidate for radioimmunotherapy (RIT regimens for treatment of larger tumor burdens not possible with α-particle radiation. Radiolabeling trastuzumab-CHX-A″-DTPA with 177Lu was efficient with a specific binding of 60.8 ± 6.8% with HER2 positive SKOV-3 cells. Direct quantitation of tumor targeting and normal tissue uptake was performed with athymic mice bearing subcutaneous and intraperitoneal LS-174T xenografts; a peak tumor %ID/g of 24.70 ± 10.29 (96 h and 31.70 ± 16.20 (72 h, respectively, was obtained. Normal tissue uptake of the RIC was minimal. Tumor targeting was also demonstrated by γ-scintigraphy. A therapy study administering escalating doses of 177Lu-trastuzumab to mice bearing three day LS-174T i.p. xenografts established the effective therapeutic dose of i.p. administered 177Lu-trastuzumab at 375 μCi with a median survival of 124.5 d while a median survival of 10 d was noted for the control (untreated group. In conclusion, trastuzumab radiolabeled with 177Lu has potential for treatment of disseminated, HER2 positive, peritoneal disease.

  10. Treatment with tandem [90Y]DOTA-TATE and [177Lu]DOTA-TATE of neuroendocrine tumours refractory to conventional therapy

    Peptide receptor radionuclide therapy (PRRT) with radiolabelled somatostatin analogues has been demonstrated to be an effective therapeutic option in patients with disseminated neuroendocrine tumours (NET). Treatment with tandem [90Y]DOTA-TATE and [177Lu]DOTA-TATE may improve the efficacy of PRRT without increasing the toxicity. In a phase II study we evaluated the feasibility of combined PPRT with a high-energy beta emitter (90Y) and a medium-energy beta/gamma emitter (177Lu) in patients with metastatic NET refractory to conventional therapy. A group of 26 patients with metastatic NET were treated with four therapeutic cycles of alternating [177Lu]DOTA-TATE (5.55 GBq) and [90Y]DOTA-TATE (2.6 GBq). A dosimetric evaluation was carried out after administration of [177Lu]DOTA-TATE to calculate the absorbed doses in healthy organs. The acute and long-term toxicities of repeated treatment were analysed. PRRT efficacy was evaluated according to RECIST. Administration of tandem [90Y]DOTA-TATE and [177Lu]DOTA-TATE induced objective responses in 42.3 % of patients with metastatic NET with a median progression-free survival longer than 24 months. Of patients with pretreatment carcinoid syndrome, 90 % showed a symptomatic response or a reduction in tumour-associated pain. The cumulative biologically effective doses (BED) were below the toxicity limit in the majority of patients, in the absence of renal function impairment The results of our study indicates that combined [90Y]DOTA-TATE and [177Lu]DOTA-TATE therapy is a feasible and effective therapeutic option in NET refractory to conventional therapy. Furthermore, the absence of kidney damage and the evaluated cumulative BEDs suggest that increasing the number of tandem administrations is an interesting approach. (orig.)

  11. [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate: comparison with [{sup 111}In-DTPA{sup 0}]octreotide in patients

    Kwekkeboom, D.J.; Bakker, W.H.; Kooij, P.P.M.; De Jong, M. [Dept. of Nuclear Medicine, Univ. Hospital Rotterdam (Netherlands); Konijnenberg, M.W. [Mallinckrodt Medical, Petten (Netherlands); Srinivasan, A.; Erion, J.L.; Schmidt, M.A.; Bugaj, J.L. [Mallinckrodt Medical, St. Louis, MO (United States); Krenning, E.P. [Dept. of Nuclear Medicine, Univ. Hospital Rotterdam (Netherlands); Dept. of Internal Medicine, University Hospital Rotterdam (Netherlands)

    2001-09-01

    The somatostatin analogue [DOTA{sup 0},Tyr{sup 3}]octreotate has a nine-fold higher affinity for the somatostatin receptor subtype 2 as compared with [DOTA{sup 0},Tyr{sup 3}]octreotide. Also, labelled with the beta- and gamma-emitting radionuclide lutetium-177, this compound has been shown to have a very favourable impact on tumour regression and animal survival in a rat model. Because of these reported advantages over the analogues currently used for somatostatin receptor-mediated radiotherapy, we decided to compare [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate ({sup 177}Lu-octreotate) with [{sup 111}In-DTPA{sup 0}]octreotide ({sup 111}In-octreotide) in six patients with somatostatin receptor-positive tumours. Plasma radioactivity after {sup 177}Lu-octreotate expressed as a percentage of the injected dose was comparable with that after {sup 111}In-octreotide. Urinary excretion of radioactivity was significantly lower than after {sup 111}In-octreotide, averaging 64% after 24 h. The uptake after 24 h, expressed as a percentage of the injected dose of {sup 177}Lu-octreotate, was comparable to that after {sup 111}In-octreotide for kidneys, spleen and liver, but was three- to fourfold higher for four of five tumours. The spleen and kidneys received the highest absorbed doses. The doses to the kidneys were reduced by a mean of 47% after co-infusion of amino acids. It is concluded that in comparison with the radionuclide-coupled somatostatin analogues that are currently available for somatostatin receptor-mediated radiotherapy, {sup 177}Lu-octreotate potentially represents an important improvement. Higher absorbed doses can be achieved to most tumours, with about equal doses to potentially dose-limiting organs; furthermore, the lower tissue penetration range of {sup 177}Lu as compared with {sup 90}Y may be especially important for small tumours. (orig.)

  12. Mechanisms of Cell Killing Response from Low Linear Energy Transfer (LET) Radiation Originating from 177Lu Radioimmunotherapy Targeting Disseminated Intraperitoneal Tumor Xenografts

    Yong, Kwon Joong; Milenic, Diane E.; Baidoo, Kwamena E.; Brechbiel, Martin W.

    2016-01-01

    Radiolabeled antibodies (mAbs) provide efficient tools for cancer therapy. The combination of low energy β−-emissions (500 keVmax; 130 keVave) along with a γ-emission for imaging makes 177Lu (T1/2 = 6.7 day) a suitable radionuclide for radioimmunotherapy (RIT) of tumor burdens possibly too large to treat with α-particle radiation. RIT with 177Lu-trastuzumab has proven to be effective for treatment of disseminated HER2 positive peritoneal disease in a pre-clinical model. To elucidate mechanisms originating from this RIT therapy at the molecular level, tumor bearing mice (LS-174T intraperitoneal xenografts) were treated with 177Lu-trastuzumab comparatively to animals treated with a non-specific control, 177Lu-HuIgG, and then to prior published results obtained using 212Pb-trastuzumab, an α-particle RIT agent. 177Lu-trastuzumab induced cell death via DNA double strand breaks (DSB), caspase-3 apoptosis, and interfered with DNA-PK expression, which is associated with the repair of DNA non-homologous end joining damage. This contrasts to prior results, wherein 212Pb-trastuzumab was found to down-regulate RAD51, which is involved with homologous recombination DNA damage repair. 177Lu-trastuzumab therapy was associated with significant chromosomal disruption and up-regulation of genes in the apoptotic process. These results suggest an inhibition of the repair mechanism specific to the type of radiation damage being inflicted by either high or low linear energy transfer radiation. Understanding the mechanisms of action of β−- and α-particle RIT comparatively through an in vivo tumor environment offers real information suitable to enhance combination therapy regimens involving α- and β−-particle RIT for the management of intraperitoneal disease. PMID:27196891

  13. Preliminary study of metabolic radiotherapy with 188Re via small animal imaging

    Baldazzi, G; Muciaccio, A; Navarria, Francesco Luigi; Pancaldi, G; Perrotta, A; Zuffa, M; Boccaccio, P; Uzunov, N; Bello, M; Bernardini, D; Mazzi, U; Moschini, G; Riondato, M; Rosato, A; Garibaldi, F; Pani, R; Antoccia, A; De Notaristefani, F; Hull, G; Cencelli, V O; Sgura, A; Tanzarella, C

    2006-01-01

    188Re is a beta- (Emax = 2.12 MeV) and gamma (155 keV) emitter. Since its chemistry is similar to that of the largely employed tracer, 99mTc, molecules of hyaluronic acid (HA) have been labelled with 188Re to produce a target specific radiopharmaceutical. The radiolabeled compound, i.v. injected in healthy mice, is able to accumulate into the liver after a few minutes. To study the effect of metabolic radiotherapy in mice, we have built a small gamma camera based on a matrix of YAP:Ce crystals, with 0.6x0.6x10 mm**3 pixels, read out by a R2486 Hamamatsu PSPMT. A high-sensitivity 20 mm thick lead parallel-hole collimator, with hole diameter 1.5 mm and septa of 0.18 mm, is placed in front of the YAP matrix. Preliminary results obtained with various phantoms containing a solution of 188Re and with C57 black mice injected with the 188Re-HA solution are presented. To increase the space resolution and to obtain two orthogonal projections simultaneously we are building in parallel two new cameras to be positioned at...

  14. Preliminary study of metabolic radiotherapy with {sup 188}Re via small animal imaging

    Antoccia, A. [Dept. of Biology, Univ. Roma3, V.le G. Marconi, I-00146 Rome (Italy); INFN, Sezione Roma3, Via della Vasca Navale 84, I-00146 Rome (Italy); Baldazzi, G. [Dept. of Physics, Univ. Bologna, V.le C. Berti-Pichat 6/2, I-40127 Bologna (Italy); INFN, Sezione Bologna, V.le C. Berti-Pichat 6/2, I-40127 Bologna (Italy); Bello, M. [Dept. of Physics, Univ. Padova, Via F. Marzolo 8, I-35131 Padova (Italy); INFN - LNL, V.le dell' Universita 2, I-35020 Legnaro(Italy)

    2006-01-15

    {sup 188}Re is a {beta}{sup -} (Emax=2.12 MeV) and {gamma} (155 keV) emitter. Since its chemistry is similar to that of the largely employed tracer, {sup 99m}Tc, molecules of hyaluronic acid (HA) have been labelled with {sup 188}Re to produce a target specific radiopharmaceutical. The radiolabeled compound, i.v. injected in healthy mice, is able to accumulate into the liver after a few minutes. To study the effect of metabolic radiotherapy in mice, we have built a small gamma camera based on a matrix of YAP:Ce crystals, with 0.6x0.6x10 mm{sup 3} pixels, read out by a R2486 Hamamatsu PSPMT. A high-sensitivity 20 mm thick lead parallel-hole collimator, with hole diameter 1.5 mm and septa of 0.18 mm, is placed in front of the YAP matrix. Preliminary results obtained with various phantoms containing a solution of {sup 188}Re and with C57 black mice injected with the {sup 188}Re-HA solution are presented. To increase the space resolution and to obtain two orthogonal projections simultaneously we are building in parallel two new cameras to be positioned at 90 degrees. They use a CsI(Tl) matrix with 1x1x5 mm{sup 3} pixels read out by H8500 Hamamatsu Flat panel PMT.

  15. Synthesis of polyacrylamide modified magnetic nanoparticles and radiolabeling with 188Re for magnetically targeted radiotherapy

    Magnetic nanoparticles were synthesized, modified with polyacrylamide, and then characterized by TEM, FTIR, VSM and PCS. Rhenium-188 (188Re) was bound to the nanoparticles by imidazolyl groups of histidine immobilized on the surface. The labeling yield was about 90% with good in vitro stability. Such nanoparticles might be useful for magnetically targeted radiotherapy

  16. 188Re-ethylene dicysteine: a novel agent for possible use in endovascular radiation therapy.

    Das, T; Banerjee, S; Samuel, G; Sarma, H D; Ramamoorthy, N; Pillai, M R

    2000-10-01

    Several agents, such as 188ReO4-, 188Re-MAG3 and 188Re-DTPA are currently under investigation as radiation sources in liquid-filled balloons for prevention of restenosis following coronary angioplasty. Bearing in mind the risk factor associated with leakage of radioactivity in the event of balloon rupture, the criteria sought in selecting suitable agents for endovascular radiation therapy (EVRT) are rapid clearance and low dose to vital organs. Since 99Tcm labelled ethylene dicysteine (EC) is a well established agent for renal tubular function imaging, the use of 186Re-ethylene dicysteine as a potential agent for prevention of restenosis after angioplasty has been evaluated previously. Therefore, it was of interest to evaluate the applicability of the more potential isotope of rhenium, 188Re, a high energy beta-emitter (Ebetamax = 2.12 MeV) with a suitable T 1/2 = 16.9 h, obtainable carrier-free from the 188W-188Re generator, as an attractive and alternative radionuclide for labelling with L,L-EC. In this paper, the preparation and pharmacological behaviour of the 188Re complex of ethylene dicysteine are reported. The complex can be prepared in high yields (99.5%) under optimized conditions of pH 2-3, at a ligand concentration of 15 mM, 50 microg (0.18 mM) carrier rhenium and using 2 mg x mL(-1) stannous chloride. On storage at 4 degrees C, the RC purity was more than 97% after 48 h when prepared under optimum conditions. Biodistribution studies in Wistar rats showed the desired characteristics of fast blood clearance and low retention of activity in the vital organs (< 2% in intestine, < 1% in stomach, < 0.5% in liver) with a high renal excretion (90.65+/-0.6%) at 3 h post-injection. These results confirm the advantages of using the 188Re-EC complex compared with perrhenate and other rhenium radiopharmaceuticals currently being used in balloons for EVRT. PMID:11130335

  17. Very stable 188Re-S4 chelates for labelling biomolecules. Preparation with highly concentrated perrhenate eluates

    Aim: The preparation and stability of a new 188Re-S4-complex [S4 (1-aza-18-crown-6)(O)C-C(SH)-C(SH)-C(O)NH-(CH2)3-NH-(CH2)3-NHC(O)- = C(SH)- C(SH )-C(O)(1-aza-18-crown-6)] was studied at therapeutic relevant radioactive concentrations. The results were compared with 188Re-MAG3 (MAG3: mercaptoacetyltriglycine) and 188Re-DMSA preparations (DMSA: dimercaptosuccinic acid) performed with the same highly concentrated [188Re]perrhenate solution (12-15 GBq/ml). Methods: The 188Re complexes were prepared by direct reduction of perrhenate (188Re-S4-complex) as well as via the 188Re-EDTA precursor complex (188Re-MAG3, 188Re-DMSA). The preparations were stabilised with 15 mg of ascorbic acid and analysed after 1, 2, and 24 hours by TLC and HPLC. Additionally, in vitro and in vivo stability studies were performed with the purified complexes. Results: After stabilisation with 15 mg of ascorbic acid, all of the complexes were nearly stable under nitrogen for hours, and only 2-8% of perrhenate was observed after 24 h. In contrast, only the 188Re-S4 complex was completely stable in vitro and in all investigated in vivo samples after separation of ligand excess and reducing agent by HPLC. Conclusion: The bridging amine group or free carboxylic groups of the S4-ligand framework make available reactive positions for coupling biomolecules to the chelate. Thus it appears that the new 188Re-S4 complexes offer the possibility of stable and high specific activity labelling of biomolecules for therapeutic application. (orig.)

  18. Comparative studies of antibody anti-CD20 labeled with 188Re

    Nuclear Medicine is an unique and important modality in oncology and the development of new tumor-targeted radiopharmaceuticals for both diagnosis and therapy is an area of interest for researchers. Rituximab (RTX) is a quimeric monoclonal antibody (mAb) (IgG 1) that specifically binds to CD20 antigen with high affinity and has been successfully used for the treatment of Non-Hodgkin Lymphoma (NHL) of cell B. The CD20 antigen is expressed over more than 90% of cell B NHL. Technetium-99m (99mTc) and rhenium-188 (188Re) are an attractive radionuclide pair for clinical use due to their favorable decay properties for diagnosis (99mTc: T1/2 = 6 h, γ radiation = 140 keV) and therapy (188Re: T1/2 = 17 h, maximum β energy = 2.12 MeV) and to their availability in the form of 99Mo/99mTc and 188W/188Re generators. The radionuclides can be conjugated to mAb using similar chemical procedures. The aim of this work was to study the labeling of anti-CD20 mAb (RTX) with 188Re using two techniques: the direct labeling method [188Re(V)] and the labeling method via the carbonyl nucleus [188Re(I)]. Besides the quality control, the radiolabeled mAb was submitted to in vivo, in vitro and ex vivo biological studies. For the direct labeling, RTX was reducing by incubation with 2-mercaptoethanol for generating sulphydryl groups (-SH) and further labeled with 188Re(V), in a study of several parameters in order to reach an optimized formulation. The labeling via the carbonyl nucleus both 99mTc and 188Re were employed through 2 different procedures: (1) labeling of intact RTX with 99mTc(I) and (2) reduced RTX (RTXred) labeled with 99mTc(I)/188Re(I). Also a parameter study was performed to obtain an optimized formulation. The quality control method for evaluating the radiochemical purity showed a good labeling yield (93%) for the direct method. The labeling method via carbonyl group, the results showed that the - SH groups of RTXred are a possible way of labeling. The formulation of 99m

  19. Synthesis, stabilization and formulation of [177Lu]Lu-AMBA, a systemic radiotherapeutic agent for Gastrin Releasing Peptide receptor positive tumors

    A robust formulation was developed for [177Lu]Lu-AMBA (177Lu-DO3A-CH2CO-G-[4-aminobenzoyl]-QWAVGHLM-NH2), a Bombesin-like agonist with high affinity for Gastrin Releasing Peptide (GRP) receptors. During optimization of labeling, the effect of several radiostabilizers was evaluated; a combination of selenomethionine and ascorbic acid showed superiority over other tested radiostabilizers. The resulting two-vial formulation maintains a radiochemical purity (RCP) of >90% for at least 2 days at room temperature. The method of stabilization should be useful for other methionine-containing peptide radiopharmaceuticals in diagnostic and therapeutic applications

  20. High treatment efficacy by dual targeting of Burkitt's lymphoma xenografted mice with a 177Lu-based CD22-specific radioimmunoconjugate and rituximab

    Dual-targeted therapy has been shown to be a promising treatment option in recurrent and/or refractory B-cell non-Hodgkin's lymphoma (B-NHL). We generated radioimmunoconjugates (RICs) comprising either a novel humanized anti-CD22 monoclonal antibody, huRFB4, or rituximab, and the low-energy β-emitter 177Lu. Both RICs were evaluated as single agents in a human Burkitt's lymphoma xenograft mouse model. To increase the therapeutic efficacy of the anti-CD22 RIC, combination therapy with unlabelled anti-CD20 rituximab was explored. The binding activity of CHX-A''-DTPA-conjugated antibodies to target cells was analysed by flow cytometry. To assess tumour targeting of 177Lu-labelled antibodies, in vivo biodistribution experiments were performed. For radioimmunotherapy (RIT) studies, non-obese diabetic recombination activating gene-1 (NOD-Rag1null) interleukin-2 receptor common gamma chain (IL2r γ null) null mice (NRG mice) were xenografted subcutaneously with Raji Burkitt's lymphoma cells. 177Lu-conjugated antibodies were administered at a single dose of 9.5 MBq per mouse. For dual-targeted therapy, rituximab was injected at weekly intervals (0.5 - 1.0 mg). Tumour accumulation of RICs was monitored by planar scintigraphy. Conjugation of CHX-A''-DTPA resulted in highly stable RICs with excellent antigen-binding properties. Biodistribution experiments revealed higher tumour uptake of the 177Lu-labelled anti-CD22 IgG than of 177Lu-labelled rituximab. Treatment with 177Lu-conjugated huRFB4 resulted in increased tumour growth inhibition and significantly longer survival than treatment with 177Lu-conjugated rituximab. The therapeutic efficacy of the anti-CD22 RIC could be markedly enhanced by combination with unlabelled rituximab. These findings suggest that dual targeting with 177Lu-based CD22-specific RIT in combination with rituximab is a promising new treatment option for refractory B-NHL. (orig.)

  1. Labeling internalizing anti-epidermal growth factor receptor variant III monoclonal antibody with 177Lu: in vitro comparison of acyclic and macrocyclic ligands

    Introduction: The monoclonal antibody (mAb) L8A4, reactive with the epidermal growth factor receptor variant III (EGFRvIII), internalizes rapidly in glioma cells after receptor binding. Combining this tumor-specific mAb with the low-energy β-emitter 177Lu would be an attractive approach for brain tumor radioimmunotherapy, provided that trapping of the radionuclide in tumor cells after mAb intracellular processing could be maximized. Materials and Methods: L8A4 mAb was labeled with 177Lu using the acyclic ligands [(R)-2-amino-3-(4-isothiocyanatophenyl)propyl]-trans-(S,S) -cyclohexane-1,2-diamine-pentaacetic acid (CHX-A''-DTPA), 2-(4-isothiocyanatobenzyl)-diethylenetriaminepenta-acetic acid (pSCN-Bz-DTPA) and 2-(4-isothiocyanatobenzyl)-6-methyldiethylenetriaminepentaacetic acid (1B4M-DTPA), and the macrocyclic ligands S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane-tetraacetic acid (C-DOTA) and α-(5-isothiocyanato-2-methoxyphenyl)-1,4,7,10-tetraazacyclododecane-1,4,7, 10-tetraacetic acid (MeO-DOTA). Paired-label internalization and cellular processing assays were performed on EGFRvIII-expressing U87.ΔEGFR glioma cells over 24 h to directly compare 177Lu-labeled L8A4 to L8A4 labeled with 125I using either iodogen or N-succinimidyl 4-guanidinomethyl-3-[125I]iodobenzoate ([125I]SGMIB). In order to facilitate comparison of labeling methods, the primary parameter evaluated was the ratio of 177Lu to 125I activity retained in U87.ΔEGFR cells. Results: All chelates demonstrated higher retention of internalized activity compared with mAb labeled using iodogen, with 177Lu/125I ratios of >20 observed for the three DTPA chelates at 24 h. When compared to L8A4 labeled using SGMIB, except for MeO-DOTA, internalized activity for 125I was higher than 177Lu from 1-8 h with the opposite behavior observed thereafter. At 24 h, 177Lu/125I ratios were between 1.5 and 3, with higher values observed for the three DTPA chelates. Conclusions: The nature of the chelate used to

  2. Pharmacokinetics and biodistribution of 177Lu-labeled multivalent single-chain Fv construct of the pancarcinoma monoclonal antibody CC49

    Lutetium-177 (177Lu) is a radionuclide of interest for radioimmunoimaging (RII) and radioimmunotherapy (RIT) on account of its short half-life (161 h) and the ability to emit both β and γ radiation. Single-chain Fv (scFv) constructs have shown advancement in cancer diagnosis and therapy due to the pharmacokinetics advantage and seem to be intriguing tools in oncology. The objective of this study was to evaluate the pharmacokinetics and biodistribution characteristics of the 177Lu-labeled tetravalent scFv of CC49 MAb and intact CC49 IgG in vivo. Conjugation and labeling conditions of multivalent scFv with 177Lu were optimized without affecting integrity and immunoreactivity. For this purpose, multivalent scFv constructs dimer, sc(Fv)2; tetramer, [sc(Fv)2]2 of the MAb CC49 were expressed as secretory proteins in Pichia pastoris. The purified scFv constructs and IgG form of CC49 were conjugated with a bifunctional chelating agent, ITCB-DTPA, and labeled with 177Lu. The comparative biodistribution, blood clearance, and tumor-targeting characteristics of 177Lu-labeled tetravalent [sc(Fv)2 ]2 construct of CC49 MAb and intact CC49 IgG were investigated in the athymic mice bearing LS-174T xenografts. Approximately, 90% of 177Lu incorporation was achieved using ITCB-DTPA chelator, and the labeled immunoconjugates maintained integrity and immunoreactivity. Blood clearance studies demonstrated an alpha half-life (t1/2 α) of 177Lu-labeled [sc(Fv)2 ]2 and IgG of CC49 at 4.40 and 9.50 min and a beta half-life (t1/2 β) at 375 and 2,193 min, respectively. At 8 h post administration, the percent of the injected dose accumulated/gram (%ID/g) of the LS-174T tumor was 6.4 ±1.3 and 8.9 ±0.6 for 177Lu-labeled [sc(Fv)2 ]2 and IgG of CC49, respectively, in the absence of l-lysine. The corresponding values were 8.0 ±0.6 and 8.4 ±1.2 in the presence of l-lysine. Renal accumulation of [sc(Fv)2 ]2 was significantly (p <0.005) reduced in the presence of l-lysine. (orig.)

  3. Pharmacokinetics and biodistribution of {sup 177}Lu-labeled multivalent single-chain Fv construct of the pancarcinoma monoclonal antibody CC49

    Chauhan, Subhash C.; Jain, Maneesh; Moore, Erik D.; Wittel, Uwe A.; Batra, Surinder K. [University of Nebraska Medical Center, Department of Biochemistry and Molecular Biology, Omaha, NE (United States); Li, Jing; Gwilt, Peter R. [University of Nebraska Medical Center, College of Pharmacy, Omaha, NE (United States); Colcher, David [Beckman Research Institute at City of Hope National Medical Center, Department of Radioimmunotherapy, Duarte, CA (United States)

    2005-03-01

    Lutetium-177 ({sup 177}Lu) is a radionuclide of interest for radioimmunoimaging (RII) and radioimmunotherapy (RIT) on account of its short half-life (161 h) and the ability to emit both {beta} and {gamma} radiation. Single-chain Fv (scFv) constructs have shown advancement in cancer diagnosis and therapy due to the pharmacokinetics advantage and seem to be intriguing tools in oncology. The objective of this study was to evaluate the pharmacokinetics and biodistribution characteristics of the {sup 177}Lu-labeled tetravalent scFv of CC49 MAb and intact CC49 IgG in vivo. Conjugation and labeling conditions of multivalent scFv with {sup 177}Lu were optimized without affecting integrity and immunoreactivity. For this purpose, multivalent scFv constructs dimer, sc(Fv){sub 2}; tetramer, [sc(Fv){sub 2}]{sub 2} of the MAb CC49 were expressed as secretory proteins in Pichia pastoris. The purified scFv constructs and IgG form of CC49 were conjugated with a bifunctional chelating agent, ITCB-DTPA, and labeled with {sup 177}Lu. The comparative biodistribution, blood clearance, and tumor-targeting characteristics of {sup 177}Lu-labeled tetravalent [sc(Fv){sub 2} ]{sub 2} construct of CC49 MAb and intact CC49 IgG were investigated in the athymic mice bearing LS-174T xenografts. Approximately, 90% of {sup 177}Lu incorporation was achieved using ITCB-DTPA chelator, and the labeled immunoconjugates maintained integrity and immunoreactivity. Blood clearance studies demonstrated an alpha half-life (t{sub 1/2} {alpha}) of {sup 177}Lu-labeled [sc(Fv){sub 2} ]{sub 2} and IgG of CC49 at 4.40 and 9.50 min and a beta half-life (t{sub 1/2} {beta}) at 375 and 2,193 min, respectively. At 8 h post administration, the percent of the injected dose accumulated/gram (%ID/g) of the LS-174T tumor was 6.4 {+-}1.3 and 8.9 {+-}0.6 for {sup 177}Lu-labeled [sc(Fv){sub 2} ]{sub 2} and IgG of CC49, respectively, in the absence of l-lysine. The corresponding values were 8.0 {+-}0.6 and 8.4 {+-}1.2 in the

  4. High treatment efficacy by dual targeting of Burkitt's lymphoma xenografted mice with a {sup 177}Lu-based CD22-specific radioimmunoconjugate and rituximab

    Weber, Tobias; Boetticher, Benedikt; Keller, Armin; Schlegelmilch, Anne; Jaeger, Dirk; Krauss, Juergen [Heidelberg University Hospital, Department of Medical Oncology, National Center for Tumor Diseases, Heidelberg (Germany); Mier, Walter; Kraemer, Susanne; Leotta, Karin [Heidelberg University Hospital, Department of Nuclear Medicine, Heidelberg (Germany); Sauter, Max; Haberkorn, Uwe [Heidelberg University Hospital, Department of Nuclear Medicine, Heidelberg (Germany); German Cancer Research Center (DKFZ), Clinical Cooperation Unit Nuclear Medicine, Heidelberg (Germany); Grosse-Hovest, Ludger [University of Tuebingen, Department of Immunology, Tuebingen (Germany); Arndt, Michaela A.E. [Heidelberg University Hospital, Department of Medical Oncology, National Center for Tumor Diseases, Heidelberg (Germany); German Cancer Research Center (DKFZ), Immunotherapy Program, National Center for Tumor Diseases, Heidelberg (Germany)

    2016-03-15

    Dual-targeted therapy has been shown to be a promising treatment option in recurrent and/or refractory B-cell non-Hodgkin's lymphoma (B-NHL). We generated radioimmunoconjugates (RICs) comprising either a novel humanized anti-CD22 monoclonal antibody, huRFB4, or rituximab, and the low-energy β-emitter {sup 177}Lu. Both RICs were evaluated as single agents in a human Burkitt's lymphoma xenograft mouse model. To increase the therapeutic efficacy of the anti-CD22 RIC, combination therapy with unlabelled anti-CD20 rituximab was explored. The binding activity of CHX-A''-DTPA-conjugated antibodies to target cells was analysed by flow cytometry. To assess tumour targeting of {sup 177}Lu-labelled antibodies, in vivo biodistribution experiments were performed. For radioimmunotherapy (RIT) studies, non-obese diabetic recombination activating gene-1 (NOD-Rag1{sup null}) interleukin-2 receptor common gamma chain (IL2r γ {sup null}) null mice (NRG mice) were xenografted subcutaneously with Raji Burkitt's lymphoma cells. {sup 177}Lu-conjugated antibodies were administered at a single dose of 9.5 MBq per mouse. For dual-targeted therapy, rituximab was injected at weekly intervals (0.5 - 1.0 mg). Tumour accumulation of RICs was monitored by planar scintigraphy. Conjugation of CHX-A''-DTPA resulted in highly stable RICs with excellent antigen-binding properties. Biodistribution experiments revealed higher tumour uptake of the {sup 177}Lu-labelled anti-CD22 IgG than of {sup 177}Lu-labelled rituximab. Treatment with {sup 177}Lu-conjugated huRFB4 resulted in increased tumour growth inhibition and significantly longer survival than treatment with {sup 177}Lu-conjugated rituximab. The therapeutic efficacy of the anti-CD22 RIC could be markedly enhanced by combination with unlabelled rituximab. These findings suggest that dual targeting with {sup 177}Lu-based CD22-specific RIT in combination with rituximab is a promising new treatment option for

  5. Formulation, radiopharmaceutical kinetics and dosimetry of the {sup 188}Re(V)-DMSA complex; Formulacion, radiofarmacocinetica y dosimetria del complejo {sup 188}Re(V)-DMSA

    Garcia S, L.; Ferro F, G. [Departamento de Materiales Radiactivos. Instituto Nacional de Investigaciones Nucleares, C.P. 52045 Salazar, Estado de Mexico (Mexico); Murphy, C.A. de; Pedraza L, M. [Departamento de Medicina Nuclear, Instituto Nacional de la Nutricion, Salvador Zubiran, Mexico D.F. (Mexico); Azorin N, J. [Departamento de Fisica, Universidad Autonoma Metropolitana Iztapalapa, Mexico D.F. (Mexico)

    1999-07-01

    It was developed through experimental design (ANOVA), a formulation to prepare the {sup 188} Re(V)-Dmsa complex. Likewise, there were realized studies of radiopharmaceutical kinetics and internal dosimetry in animals, its normal and with induced tumors, considering an open bi compartmental model using the MIRD methodology. The {sup 188} Re(V)-Dmsa complex was obtained with a radiochemical purity greater than 95% incubating 30 min at 90 Centigrade under the following formulation: [SnCl{sub 2}] = 1.4 mg/ml, [ascorbic acid] = 0.5 mg/ml, p H = 2.0 - 3.0. The stability test of the formulation, shows that after 48 h of its preparation, does not produce radiolytic degradation neither chemical decomposition. The radiopharmaceutical kinetics data show an average residence time 7.2h, velocity constant {alpha} = 0.6508h{sup -1} and {beta} = 0.1046 h{sup -1} with an apparent distribution volume 6.9 l. The main elimination via was renal and it was observed osseous caption with an accumulated activity 522.049 {+-} 62 MBq h (residence time 14.1094 {+-} 1.69h). In according with the dosimetric calculations, by each 37 MBq injected, the equivalent dose at the tumor was 9.67{+-} 0.33 Sv/g, for an effective dose 0.292 {+-} 0.0017 mSv/MBq. The images obtained in the gamma camera of the mice with induced tumors, show that do not have significant accumulation in the metabolic organs. The caption in bone and in tumors induced of the {sup 188} Re(V)-Dmsa complex, show its potential for be used as a palliative agent for pain in patients with osseous metastasis and in the treatment of tumors of soft tissue. (Author)

  6. Labeling of MDP with {sup 188}Re for bone tumour therapy

    Barbezan, Angelica B.; Osso Junior, Joao A., E-mail: jaosso@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    {sup 188}Re is one of the most attractive radioisotopes for a variety of therapeutic applications in nuclear medicine, due to its physical decay properties, such as {beta}{sup -} emission of 2.12 MeV, {gamma} emission of 155 keV and half life of 16.9 hours. Biphosphonates are potent inhibitors of osteoclastic bone resorption and are effective in several diseases that cause bone fragility and bone metastases. Because of these characteristics, labeled biphosphonates have been studied for bone pathologies, also acting as palliation of bone pain in case of metastasis.The aim of this study was to optimize the labeling of a phosphonate-MDP (Sodium Methylene Diphosphonate) with {sup 188}Re for use in bone pain palliation. {sup 188}Re was obtained by eluting a {sup 188}W-{sup 188}Re generator from POLATOM. The labeling was performed at room temperature using MDP, SnCl{sub 2} as reducing agent and ascorbic acid. The variables studied were: Mass of ligand (3, 6 and 10 mg), reducing agent mass (5, 7, 10 and 11 mg), ascorbic acid mass (1, 3, 5 and 6 mg), pH (1 and 2) and time of reaction (15, 60, 120, 360 and 4320 minutes), that also reflected the stability of the radiopharmaceutical. The radiochemical control, that also measures the labeling efficiency was evaluated by paper chromatography using Whatman 3MM paper and the solvents acetone and 0.9%NaCl. The best formulation was the following: Mass of ligand MDP: 10 mg, mass of SnCl{sub 2}: 5 mg, ascorbic acid mass: 3 mg, time of reaction: 30 minutes, pH: 1. Under optimum conditions, {sup 188}Re MDP radiolabeling yield was 98,07% and the radiopharmaceutical was stable up to 72 h. (author)

  7. Intracoronary radionuclide therapy with liquid 188Re-filled balloons: Radiopharmaceutical and dosimetric studies

    Full text: Percutaneous transluminal coronary angioplasty (PCTA) associated with radioactive liquid-filled balloons has demostrated useful to inhibit the growth of neointimal tissue and as consequence offers a potential method to decrease restenosis rate. Near 40 to 60% of the patients suffered from restenosis, being necessary to reiterate angioplasty. The spectrum of late effects from the variety of sources types, dosimetric aspects and delivery systems has not became clear. An attractive radionucleid for this purpose is 188Re, that is eluated from a 188W/188Re generator. The generator can be used during 6 months, depending on the initial activity. The specific activity can be increased by a concentration system up to a maximum of 20 GBq/mL. The present study had the purpose of optimizing the relation risk/benefit during a procedure of brachytherapy with 188Re associated to angioplasty. The possibility of balloon rupture exists, with the passage of the radioactive solution towards the patient bloodstream. In order to increase the security during the treatment the evaluation of different agents such as 188Re- DTPA, 188Re-Citrate and 188Re-EC vs 188ReO4- (as the standard agent) was performed. Labelling procedures were optimized considering pH, temperature, reaction time and carrier adition. Dosimetric studies using Mirdose 3, after iv injection to Wistar rats of the three radiopharmaceuticals were performed. Biodistrubion at 1 and 3 hs post-administration and dose estimation showed no difference between all the radiopharmaceuticals, presenting low uptake in thyroid and stomach, and faster renal elimination than 188ReO4-, with smaller residence times in all the organs. As the preparation of 188Re-Citrate and 188Re-EC required less strong conditions than 188Re-DTPA, one of these radiopharmaceuticals could be selected to improve the security of the procedure. A second point of this study was the evaluation of a number of safety requirements in order to estimate

  8. Preparation of DOTA-TATE and DOTA-NOC freeze-dried kits for formulation of patient doses of 177Lu-labeled agents and their comparison for peptide receptor radionuclide therapy application

    The objective of the present work is to prepare freeze-dried DOTA-TATE and DOTA-NOC kits for the easy and convenient preparation of patient doses of 177Lu-DOTA-TATE and 177Lu-DOTA-NOC, respectively at the hospital radiopharmacy and to compare the radio-peptides with respect to their radiochemical and biological behaviors. Freeze-dried kits of DOTA-TATE and DOTA-NOC, comprising a lyophilized mixture of 200 μg of DOTA-peptide, 80 mg of gentisic acid and 13.9 mg of ammonium acetate were prepared. Therapeutic doses of 177Lu-labeled peptides (up to 200 mCi, 7.4 GBq) were prepared using these kits and 177Lu, produced in-house, with >99 % radiochemical purity and high stability following an easy and convenient protocol. Comparative pharmacokinetic behavior of the radio-peptides was studied by carrying out biodistribution studies in normal Wistar rats which revealed higher retention of activity in several major organs and slower renal clearance for 177Lu-DOTA-NOC compared to that of 177Lu-DOTA-TATE. Preliminary pharmacokinetic studies, carried out in limited number of patients suffering from cancers of neuroendocrine origins, showed lower accumulation of activity in vital organs and faster renal clearance of 177Lu-DOTA-TATE compared to that of 177Lu-DOTA-NOC. (author)

  9. Assessment of 188Re marked anti MHC class Ⅱ antibody by peripheral blood mononuclear cells stimulated by donor alloantigen

    DING Guo-ping; CAO Li-ping; LIU Jie; LIU Da-ren; QUE Ri-sheng; ZHU Lin-hua; ZHOU Yi-ming; MAO Ke-jie; HU Jun-an

    2011-01-01

    Background Previous studies showed that anti MHC-Ⅱ monoclone antibody (MAb) only had partial inhibiting effect of alloreactive mixed lymphocyte reaction (MLR) in vitro and it was unsteady and non-persistent. The aim of this research was to determine whether radioactive isotope 188Re marked MHC-Ⅱ antibody could benefit the allograft acceptance in transplantation as compared to normal MHC-Ⅱ antibody.Methods 188Re was incorporated to 2E9/13F(ab')2 which is against swine MHC class Ⅱ antigen (MAb-188Re). Porcine peripheral blood mononuclear (PBMC) cells were examined for proliferation and cytokine mRNA expression after stimulation with MHC-Ⅱ MAb or MAb-188Re.Results The proliferative response of recipient PBMCs in mixed lymphocyte reaction (MLR) to donor alloantigen showed that the stimulation index of MAb-188Re group was significantly lower than the MHC-Ⅱ MAb group and control (P<0.05). mRNA expression of interleukin 2, interferon Y and tumor necrosis factor α (type 1 cytokines) was lower in MAb-188Re group than the MHC-Ⅱ MAb group, while interleukin 10 (type 2 cytokines) was higher in MAb-188Re group in the first 24 hours.Conclusion MAb-188Re could help the graft acceptance by inhibiting T cell proliferation, lowering the expression of type 1 cytokines and elevating the type 2 cytokines produced by PBMC.

  10. Dosimetric evaluation of nanotargeted 188Re-liposome with the MIRDOSE3 and OLINDA/EXM programs

    The OLINDA/EXM computer code was created as a replacement for the widely used MIRDOSE3 code for radiation dosimetry in nuclear medicine. A dosimetric analysis with these codes was performed to evaluate nanoliposomes as carriers of radionuclides (188Re-liposomes) in colon carcinoma-bearing mice. Pharmacokinetic data for 188Re-N, N-bis (2-mercaptoethyl)-N', N'-diethylethylenediamine (188Re-BMEDA) and 188Re-liposome were obtained for estimation of absorbed doses in normal organs. Radiation dose estimates for normal tissues were calculated using the MIRDOSE3 and OLINDA/EXM programs for a colon carcinoma solid tumor mouse model. Mean absorbed doses derived from 188Re-BMEDA and 188Re-liposome in normal tissues were generally similar as calculated by MIRDOSE3 and OLINDA/EXM programs. One notable exception to this was red marrow, wherein MIRDOSE3 resulted in higher absorbed doses than OLINDA/EXM (1.53- and 1.60-fold for 188Re-BMEDA and 188Re-liposome, respectively). MIRDOSE3 and OLINDA have very similar residence times and organ doses. Bone marrow doses were estimated by designating cortical bone rather than bone marrow as a source organ. The bone marrow doses calculated by MIRDOSE3 are higher than those by OLINDA. If the bone marrow is designated as a source organ, the doses estimated by MIRDOSE3 and OLINDA programs will be very similar. (author)

  11. Comparative study on DOTA-derivatized bombesin analog labeled with 90Y and 177Lu: in vitro and in vivo evaluation

    Introduction: The aim of the study was to compare in vitro and in vivo a novel DOTA-chelated bombesin (BN) analog of the amino acid sequence, QRLGNQWAVGHLM-CONH2 (BN[2-14]NH2), labeled with 90Y and 177Lu, for its potential use in targeted radiotherapy of tumors expressing gastrin releasing peptide (GRP) receptors. The same amino acid sequence, but with different chelator, referred as BN1.1 (Gly-Gly-Cys-Aca-QRLGNQWAVGHLM-CONH2), has already been studied and reported; however, the DOTA-chelated one, suitable for labeling with M+3 type radiometals, was not yet described. Methods: The conditions for labeling of DOTA-BN[2-14]NH2 with noncarrier added 90Y and with 177Lu [specific activity (SA), 15 Ci/mg Lu] were investigated and optimized to provide 90Y-DOTA-BN[2-14]NH2 and 177Lu-DOTA-BN[2-14]NH2 of high SA. The stability of the radiolabeled compounds in human serum was evaluated over a period of 24 h. The human prostate cancer cell line PC-3, known to express GRP receptors, was used for in vitro evaluation of radiolabeled peptide affinity to GRP receptors and for assessment of cytotoxicity of both nonlabeled and radiolabeled peptide. Biodistribution accompanied by receptor blocking was studied in normal Swiss mice. Results: 90Y-DOTA-BN[2-14]NH2 and 177Lu-DOTA-BN[2-14]NH2 were obtained with radiochemical yield >98% and high SA (67.3 GBq 90Y/μmol and 33.6 GBq 177Lu/μmol, respectively). They were stable when incubated in human serum for up to 24 h. The binding affinities of DOTA-BN[2-14]NH2 and both natY- and natLu-labeled analogs to GRP receptors were high (IC50=1.78, 1.99, and 1.34 nM, respectively), especially for the natLu-DOTA-BN[2-14]NH2 complex. The cytotoxicity study of DOTA-BN[2-14]NH2 to PC-3 cells revealed an IC50=6300 nM after 72 h of exposition, while the labeled derivatives showed no significant cytotoxic effect. The internalization rate to PC-3 cells was more rapid for 177Lu-labeled peptide (84.87%) than for the 90Y-labeled one (80.79%), while the efflux

  12. Biological distribution of 51Cr-heparin

    The kinetics of heparin in normal Wistar rats using the radioactive tracer 51Cr, has been studied. The labeled and purified 51Cr-heparin was injected into rats intravenously and by intraperitoneal injection. In measuring the radioactivity of organs it was possible to conclude that the tissues rich in mast cells, liver and spleen, were found to take up the greater amounts of heparin. The curve that represents the logarithm of the concentration of heparin versus time is biexponential. The half-lives of the two exponential were determined. The volume of distribution, the rate constant and the renal clearance were determined by the values of the plasma levels and urinary excretions. The biological half-time, the turnover rate and the turnover time were determined by measuring the residual radioactivity of the total body and urinary excretions. With the data obtained from the mentioned experiments a compartmental model was performed in which the plasma is the central compartment for the distribution of the drug, exchanging with another extraplasmatic compartment and finally the drug being stored in reticulo endothelial system cells. (Author)

  13. Labelling of biorelated compounds and monoclonal antibodies with 188-Re,186-Re and 99mTc

    Some bio-related compounds were labelled with 188Re and 186Re 188Re was obtained from 188W/188Re generator which was produced by neutron irradiation of enriched 186WO3 target (99.79%) in JRR-2 and 186Re was supplied by Production Div., Department of Radioisotopes, JAERI, Japan. Rhenium labelling involved reduction of perrhenate with SnCl2.2H20 in HCI. Bio-related compounds citrate and gluconate were then labelled with reduced rhenium. The labelling yield of labelled compounds as determined by thin-layer chromatography were greater than 98% and 94% for 188Re-citrate and gluconate, respectively. Monoclonal antibodies (mouse,lgG2A and lgG;Fab'2, human lgG2A; anti-hepatoma and IgG) were also successfully labelled with 188Re, 186Re, and 99mTc by direct method using citrate and glucoheptonate as transchelating agents

  14. Experimental study on target treatment of nasopharyngeal carcinoma using 188Re-BAC5 combined with PYM-BAC5

    Objective: Combination of radiation and chemical agents was supposed to have better effect on nasopharyngeal cancer. This study compared the in vitro inhibiting effects of 188Re-monoclonal anti- body (BACs) with or without pingyangmycin conjugated BACs (PYM-BAC5) on nasopharyngeal carcinoma cells (CNE2). Methods: 188Re-BAC5 was prepared using 2-mereaptoethanol (ME), citric acid and tartaric acid as reducing and transchelation agents. Oxidized dextran T-40 (polyaldehyde dextran, PAD ) was used to conjugate PYM to BAC5. 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenylte-trazolium bromide (MTT) method was applied to assess anti-tumor effects of 188Re-BAC5 and PYM-BAC5 on CNE2 cells. Results: The labeling efficiency of 188Re-BACs was 92%-95% with a radioactive concentration of 5254 kBq/ml. The composition of PYM-BAC5 was m (PYM): m (BAC5)=1: 0.526, or n (PYM): n(BAC5)=1:51. The inhibition effects of each treatment regime were in a dose dependent manner. The 50% inhibition doses (IC50) of 188Re-BAC5, 188Re-mIgG and 188ReO4- were 264, 1062 and 882 kBq/ml, respectively. The IC50 of the PYM-BAC5 and free PYM were 10.07 and 63.60 μg/ml, respectively. Combining 188Re-BAC5 and PYM-BACs reduced the IC50 of 1'88Re-BAC5 and PYM-BACs down to 32.1 kBq/ml and 1.70 μg/ml. Conclusions: It was proved that targeted therapy had better anti-tumor effect. The combination of targeted radiation and chemical agents (188Re-BAC5 + PYM-BAC5) obtained the best therapeutic effect on cultured CNE2 cells. (authors)

  15. Renal function affects absorbed dose to the kidneys and haematological toxicity during {sup 177}Lu-DOTATATE treatment

    Svensson, Johanna; Berg, Gertrud [Sahlgrenska University Hospital, Department of Oncology, Goeteborg (Sweden); Waengberg, Bo [Sahlgrenska University Hospital, Department of Surgery, Goeteborg (Sweden); Larsson, Maria [University of Gothenburg, Department of Radiation Physics, Institute of Clinical Sciences, The Sahlgrenska Academy, Goeteborg (Sweden); Forssell-Aronsson, Eva; Bernhardt, Peter [University of Gothenburg, Department of Radiation Physics, Institute of Clinical Sciences, The Sahlgrenska Academy, Goeteborg (Sweden); Sahlgrenska University Hospital, Department of Medical Physics and Medical Bioengineering, Goeteborg (Sweden)

    2015-05-01

    Peptide receptor radionuclide therapy (PRRT) has become an important treatment option in the management of advanced neuroendocrine tumours. Long-lasting responses are reported for a majority of treated patients, with good tolerability and a favourable impact on quality of life. The treatment is usually limited by the cumulative absorbed dose to the kidneys, where the radiopharmaceutical is reabsorbed and retained, or by evident haematological toxicity. The aim of this study was to evaluate how renal function affects (1) absorbed dose to the kidneys, and (2) the development of haematological toxicity during PRRT treatment. The study included 51 patients with an advanced neuroendocrine tumour who received {sup 177}Lu-DOTATATE treatment during 2006 - 2011 at Sahlgrenska University Hospital in Gothenburg. An average activity of 7.5 GBq (3.5 - 8.2 GBq) was given at intervals of 6 - 8 weeks on one to five occasions. Patient baseline characteristics according to renal and bone marrow function, tumour burden and medical history including prior treatment were recorded. Renal and bone marrow function were then monitored during treatment. Renal dosimetry was performed according to the conjugate view method, and the residence time for the radiopharmaceutical in the whole body was calculated. A significant correlation between inferior renal function before treatment and higher received renal absorbed dose per administered activity was found (p < 0.01). Patients with inferior renal function also experienced a higher grade of haematological toxicity during treatment (p = 0.01). The residence time of {sup 177}Lu in the whole body (range 0.89 - 3.0 days) was correlated with grade of haematological toxicity (p = 0.04) but not with renal absorbed dose (p = 0.53). Patients with inferior renal function were exposed to higher renal absorbed dose per administered activity and developed a higher grade of haematological toxicity during {sup 177}Lu-DOTATATE treatment. The study confirms the

  16. Time- and dose rate-related effects of internal 177Lu exposure on gene expression in mouse kidney tissue

    Introduction: The kidneys are the dose-limiting organs in some radionuclide therapy regimens. However, the biological impact of internal exposure from radionuclides is still not fully understood. The aim of this study was to examine the effects of dose rate and time after i.v. injection of 177LuCl3 on changes in transcriptional patterns in mouse kidney tissue. Methods: To investigate the effect of dose rate, female Balb/c nude mice were i.v. injected with 11, 5.6, 1.6, 0.8, 0.30, and 0 MBq of 177LuCl3, and killed at 3, 6, 24, 48, 168, and 24 hours after injection, respectively. Furthermore, the effect of time after onset of exposure was analysed using mice injected with 0.26, 2.4, and 8.2 MBq of 177LuCl3, and killed at 45, 90, and 140 days after injection. Global transcription patterns of irradiated kidney cortex and medulla were assessed and enriched biological processes were determined from the regulated gene sets using Gene Ontology terms. Results: The average dose rates investigated were 1.6, 0.84, 0.23, 0.11 and 0.028 mGy/min, with an absorbed dose of 0.3 Gy. At 45, 90 and 140 days, the absorbed doses were estimated to 0.3, 3, and 10 Gy. In general, the number of differentially regulated transcripts increased with time after injection, and decreased with absorbed dose for both kidney cortex and medulla. Differentially regulated transcripts were predominantly involved in metabolic and stress response-related processes dependent on dose rate, as well as transcripts associated with metabolic and cellular integrity at later time points. Conclusion: The observed transcriptional response in kidney tissue was diverse due to difference in absorbed dose, dose rate and time after exposure. Nevertheless, several transcripts were significantly regulated in all groups despite differences in exposure parameters, which may indicate potential biomarkers for exposure of kidney tissue

  17. Accurate assessment of long-term nephrotoxicity after peptide receptor radionuclide therapy with {sup 177}Lu-octreotate

    Sabet, Amir; Ezziddin, Khaled; Reichman, Karl; Haslerud, Torjan; Ahmadzadehfar, Hojjat; Biersack, Hans-Juergen; Ezziddin, Samer [University Hospital Bonn, Department of Nuclear Medicine, Bonn (Germany); Pape, Ulrich-Frank [Charite, University Medicine Berlin, Campus Virchow Clinic, Department of Hepatology and Gastroenterology, Berlin (Germany); Nagarajah, James [University Hospital, Department of Nuclear Medicine, Essen (Germany)

    2014-03-15

    Renal radiation during peptide receptor radionuclide therapy (PRRT) may result in glomerular damage, a potential reduction of glomerular filtration rate (GFR) and ultimately lead to renal failure. While reported PRRT nephrotoxicity is limited to data derived from serum creatinine - allowing only approximate estimates of GFR - the aim of this study is to accurately determine PRRT-induced long-term changes of renal function and associated risk factors according to state-of-the-art GFR measurement. Nephrotoxicity was analysed using {sup 99m}Tc-diethylenetriaminepentaacetic acid (DTPA) clearance data of 74 consecutive patients with gastroenteropancreatic neuroendocrine tumours (GEP NET) undergoing PRRT with {sup 177}Lu-octreotate. The mean follow-up period was 21 months (range 12-50) with a median of five GFR measurements per patient. The change of GFR was analysed by linear curve fit. Potential risk factors including diabetes mellitus, arterial hypertension, previous chemotherapy, renal impairment at baseline and cumulative administered activity were analysed regarding potential impact on renal function loss. In addition, Common Terminology Criteria for Adverse Events (CTCAE) v3.0 were used to compare nephrotoxicity determined by {sup 99m}Tc-DTPA clearance versus serum creatinine. The alteration in GFR differed widely among the patients (mean -2.1 ± 13.1 ml/min/m{sup 2} per year, relative yearly reduction -1.8 ± 18.9 %). Fifteen patients (21 %) experienced a mild (2-10 ml/min/m{sup 2} per year) and 16 patients (22 %) a significant (>10 ml/min/m{sup 2} per year) decline of GFR following PRRT. However, 11 patients (15 %) showed an increase of >10 ml/min/m{sup 2} per year. Relevant nephrotoxicity according to CTCAE (grade ≥3) was observed in one patient (1.3 %) with arterial hypertension and history of chemotherapy. Nephrotoxicity according to serum creatinine was discordant to that defined by GFR in 15 % of the assessments and led to underestimation in 12 % of

  18. Peptide receptor radionuclide therapy with {sup 177}Lu-DOTATATE: the IEO phase I-II study

    Bodei, Lisa; Grana, Chiara M.; Baio, Silvia M.; Lombardo, Dario; Chinol, Marco; Paganelli, Giovanni [European Institute of Oncology, Division of Nuclear Medicine, Milan (Italy); Cremonesi, Marta; Ferrari, Mahila E. [European Institute of Oncology, Division of Medical Physics, Milan (Italy); Fazio, Nicola [European Institute of Oncology, Division of Medical Oncology, Milan (Italy); Iodice, Simona [European Institute of Oncology, Division of Epidemiology and Biostatistics, Milan (Italy); Bartolomei, Mirco [European Institute of Oncology, Division of Nuclear Medicine, Milan (Italy); M. Bufalini Hospital, Division of Nuclear Medicine, Cesena, FC (Italy); Sansovini, Maddalena [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori, Unit of Radiometabolic Medicine, Meldola, FC (Italy)

    2011-12-15

    Peptide receptor radionuclide therapy (PRRT) is used in tumours expressing type 2 somatostatin receptors (sst{sub 2}), mainly neuroendocrine. The aim of this prospective phase I-II study was to evaluate the toxicity and efficacy of {sup 177}Lu-DOTATATE in multiple cycles. Fifty-one consecutive patients with unresectable/metastatic sst{sub 2}-positive tumours, divided into two groups, received escalating activities (3.7-5.18 GBq/cycle, group 1; 5.18-7.4 GBq/cycle, group 2) of {sup 177}Lu-DOTATATE. Cumulative activities ranged from 3.7 to 29.2 GBq (median 26.4 GBq in median 6 cycles, group 1, 21 patients) and 5.55 to 28.9 GBq (median 25.2 GBq in 4 cycles, group 2, 30 patients), based on dosimetry. No major acute or delayed renal or haematological toxicity occurred (one grade 3 leukopenia and thrombocytopenia). Cumulative renal absorbed doses were 8-37 Gy (9-41 Gy bioeffective doses). A median decrease of creatinine clearance of 21.7% 6 months after PRRT, 23.9% after 1 year and 27.6% after 2 years was observed. Higher losses (>20%) occurred in patients with risk factors for renal toxicity, particularly hypertension and diabetes. Cumulative bone marrow doses were <1.5 Gy. Blood elements showed a progressive mild drop during cycles and recovered during follow-up (median 30 months). Thirty-nine patients were progressive at enrolment. Partial and complete responses occurred in 15 of 46 (32.6%) assessable patients. The median time to progression was 36 months. Overall survival was 68% at 36 months. Non-responders and patients with extensive tumour involvement had lower survival. {sup 177}Lu-DOTATATE was well tolerated up to 29 GBq cumulative activity (up to 7.4 GBq/cycle). The maximum tolerated dose/cycle was not reached. However, considering the individual bone marrow function and the presence of risk factors for kidney toxicity, it seems safer to divide cumulative activities into lower activity cycles. (orig.)

  19. Development of a technology for the preparation of 188W-188Re generators

    A big interest has recently arisen concerning the use of Rhenium-188 (188Re) for various medical applications. Tumor therapy with antibodies labeled with 188Re is the main application, but it is being studied its application in carcinomas of medullar thyroid, bone pain palliation and radionuclide synovectomy, among others. Rhenium-188 decays 79% to the ground state of stable 188Os (Eβ1max - 2,11 MeV) and 20% to the first excited state (Eβ2max = 1,97 MeV). The deexcitation of this state gives a 155 keV gamma ray (15r%) which can be detected by imaging. Another great advantage is the viability of carrier-free 188Re from the decay of 188W (t1/2 = 69.4 days) in a generator system. The objective of this work is the development of the technology for the preparation of 188W- 188Re generators. To accomplish this, the steps of the work are: preparation of the targets of W; irradiation of W targets in order to measure the activation and radionuclidic impurities; development of 188W-188Re generators; development of a method for the quality control of 188Re: chemical, radiochemical and radionuclidic purities. The study of alumina-based generators was performed with the irradiation of targets of natural metallic W and W03 and showed that this kind of generator will only be viable with the importation of 188W, due to the low neutron flux of the Reactor IEA-R1 Reactor for the commercial routine production of this radioisotope, but the technology of production and quality control were successful. The gel type chromatographic generators of WZr were produced with natural WO3 targets and showed that, if enriched targets are to be used and with the power upgrade of the IEA-R1 Reactor, they can be produced by the Radiopharmacy Center at IPEN-SP. The quality control methodology were determined and the results were inside the limits given by the Pharmacopoeia. (author)

  20. Improved conditions for labeling EDTMP with 188Re for bone pain palliation

    Introduction: Ethilenediamine tetramethylene phosphonate (EDTMP) is a tetraphosphonate ligand which, when labeled with 188Re, can be used for relief of metastatic bone pain. The preferential localization of phosphonate complexes in bone is attributed to their affinity for calcium, and tetraphosphonates may be equal or superior to diphosphonates in this regard. In the present study, it was aimed to determine optimal conditions for preparation of a kit of EDTMP to be labeled with 188Re. Methods: EDTMP was dissolved in NaOH 1N, and alkalinity was reversed with HCl till pH 2, when SnCl2. 2H20 and also ascorbic acid were introduced in the mixture, followed by Na188ReO4. The preparation was incubated in water bath for 30 minutes and after cooling radiochemical purity was assessed. Optimization of the process consisted in varying the values of EDTMP mass (20, 30, 40 mg) SnCl2.2H20 concentration (0.5, 1.0, 2.0 and 3.0 mg/mL), and reaction time (15 and 30 minutes). Radiochemical purity and stability were ascertained in vitro and also in Swiss mice. Bone/muscle uptake ratio was calculated from %ID/g of these organs. Results: The best 188Re-EDTMP complex was obtained with 40 mg of the ligand and 2 mg/mL of stannous chloride heated during 15 minutes, and the product was radiochemically stable during 24 hours. Kidney and bone uptake were very significant (respectively 4.5 ± 0.5% and 3.1 ± 0.3 %ID/g). Bone/muscle ratio observed four hours post-injection was also very adequate (28.5). Conclusions: A stable and biologically useful complex of 188Re-EDTMP can be prepared with high concentration of EDTMP and considerable uptake by bone. It compares favorably with 153Sm-EDTMP, as 188Re has more advantageous radioisotopic properties than 153Sm, and it can be recommended for further studies in conditions of painful bone metastases

  1. Monomeric, dimeric and multimeric system of RGD peptides radiolabeled with {sup 177}Lu for tumors therapy that expressing αβ integrin s; Sistema monomerico, dimerico y multimerico de peptidos de RGD radiomarcados con {sup 177}Lu para terapia de tumores que expresan integrinas αβ

    Luna G, M. A.

    2014-07-01

    The conjugation of peptides to gold nanoparticles (AuNPs) produces biocompatible and stable multimeric systems with target-specific molecular recognition. Peptides based on the cyclic Arg-Gly-Asp (RGD) sequence have been reported as high affinity agents for the α(v)β(3) and α(v)β(5) integrin. The aim of this research was to prepare a multimeric system of {sup 177}Lu-labeled gold nanoparticles conjugated to c[RGDfK(C)] [cyclo(Arg-Gly-Asp-Phe-Lys(Cys)] peptides and to compare the radiation absorbed dose with that of {sup 177}Lu-labeled monomeric and dimeric RGD peptides to α(v)β(3) integrin-positive U87MG tumors in mice, as well as, evaluate the in vitro potential {sup 177}Lu-AuNP-c[RGDfK(C)] as a plasmonic photothermal therapy and targeted radiotherapy system in MCF7 breast cancer cells. DOTA-GGC (1,4,7,10-tetraaza cyclododecane-N,N,N-tetraacetic-Gly-Gly-Cys) and c[RGDfK(C)] peptides were synthesized and conjugated to AuNPs by the spontaneous reaction of the thiol groups. Tem, UV-Vis, XP S, Raman and Far-IR spectroscopy techniques demonstrated that AuNPs were functionalized with the peptides. To obtain {sup 177}Lu-AuNP-c[RGDfK(C)], the {sup 177}Lu-DOTA-GGC radio peptide was first prepared and added to a solution of AuNPs followed by c[RGDfK(C)] (25 μL, 5 μM) at 18 grades C for 15 min. {sup 177}Lu-DOTA-GGC, {sup 177}Lu- DOTA-cRGDfK and {sup 177}Lu-DOTA-E-c(RGDfK){sub 2} were prepared by adding {sup 177}LuCl{sub 3} (370 MBq) to 5 μL (1 mg/ml) of the DOTA derivative diluted with 50 μL of 1 M acetate buffer at ph 5. The mixture was incubated at 90 grades C in a block heater for 30 min. Radiochemical purity was determined by ultrafiltration and HPLC analyses. After laser irradiation, the presence of c[RGDfK(C)]-AuNP in cells caused a significant increase in the temperature of the medium (50.5 grades C, compared to 40.3 grades C without AuNPs) resulting in a significant decrease in MCF7 cell viability down to 9 %. After treatment with {sup 177}Lu

  2. Organ doses from hepatic radioembolization with 90Y, 153Sm, 166Ho and 177Lu: A Monte Carlo simulation study using Geant4

    Hashikin, N. A. A.; Yeong, C. H.; Guatelli, S.; Abdullah, B. J. J.; Ng, K. H.; Malaroda, A.; Rosenfeld, A. B.; Perkins, A. C.

    2016-03-01

    90Y-radioembolization is a palliative treatment for liver cancer. 90Y decays via beta emission, making imaging difficult due to absence of gamma radiation. Since post-procedure imaging is crucial, several theranostic radionuclides have been explored as alternatives. However, exposures to gamma radiation throughout the treatment caused concern for the organs near the liver. Geant4 Monte Carlo simulation using MIRD Pamphlet 5 reference phantom was carried out. A spherical tumour with 4.3cm radius was modelled within the liver. 1.82GBq of 90Y sources were isotropically distributed within the tumour, with no extrahepatic shunting. The simulation was repeated with 153Sm, 166Ho and 177Lu. The estimated tumour doses for all radionuclides were 262.9Gy. Tumour dose equivalent to 1.82GBq 90Y can be achieved with 8.32, 5.83, and 4.44GBq for 153Sm, 166Ho and 177Lu, respectively. Normal liver doses by the other radionuclides were lower than 90Y, hence beneficial for normal tissue sparing. The organ doses from 153Sm and 177Lu were relatively higher due to higher gamma energy, but were still well below 1Gy. 166Ho, 177Lu and 153Sm offer useful gamma emission for post-procedure imaging. They show potential as 90Y substitutes, delivering comparable tumour doses, lower normal liver doses and other organs doses far below the tolerance limit.

  3. Radiolabelled of c-DOTA-RGD and c-DOTA-RGDf with 177Lu and evaluation in vitro and in vivo stability

    Integrin αvβ3 has a critical role in tumor angio genesis and metastasis. Radiolabelled peptides based on the Arg-Gly-Asp (RGD) sequence have been reported as radiopharmaceuticals with high affinity and selectivity for the αvβ3 integrin. The aim of this study was to label c-DOTA-RGD and c-DOTA-RGDf peptides with 177Lu and to evaluate their in vitro and in vivo stability as potential specific therapeutic radiopharmaceuticals. Labelled was carried out by direct reaction of 177LuCl3 with c-DOTA-RGD peptides in 1 M acetate buffer ph 5.5 at 90o C for 30 min. Radiochemical purity and stability studies were realized by reversed phase HPLC and I TLC-Sg analyses in human serum and saline solution. Biological recognition was performed using MCF7 tumor cells (positive αvβ3) and in athymic mice with induced MCF7 tumors. Molecular mechanics and quantum mechanics calculations were performed to explain experimental results associated with the molecular recognition. 177Lu-DOTA-RGD and 177Lu-DOTA-RGDf were obtained with radiochemical purities > 95%, showing adequate in vitro and in vivo stability and specific binding to □v□3 receptors. (Author)

  4. In vitro and in vivo studies in Balb-c and nude mice of a new 177Lu-Bombesin analog developed for prostate tumor diagnosis and treatment

    In this work we describe the radiolabeling with 177Lu and some properties of the novel bombesin analog BBNp6 - DOTA-X-BBN(6-14), where X is a spacer of six aminoacids. Bombesin (BBN) is an analog of human gastrin releasing peptide (GRP) isolated from the skin of the frog Bombina bombina in 1970. Development of radiolabeled BBN derivatives as agents for diagnostic imaging and systemic radiotherapy has increased considerable because of the observation that GRP receptors (GRPr) are over-expressed in a variety of human tumor cells, such as prostate tumor cells. 177Lu-labeled peptides are attractive due to the excellent radiophysical properties and commercial availability of the radiometal. BBNp6 was labeled with high yield after reacting with 92.5 MBq of 177LuCl3 at 90 deg C for 30 minutes and this mixture kept stable for more than 96 hours at 4 deg C and 1 hour in human plasma. In vivo studies showed a multicompartimental distribution model with fast blood clearance, mainly performed by renal pathway. In addition, 177Lu-BBNp6 showed high affinity for PC-3 tumor xenografts, but not for pancreas and intestine (GRP positive tissues), suggesting its specificity and usefulness for prostate tumor treatment. Moreover, scintigraphic images showed that this derivative can also be a tool in this tumor diagnosis. So, BBNp6 is a promising radiopharmaceutical for prostate tumor imaging and treatment. (author)

  5. An approach for conjugation of 177 Lu- DOTA-SCN- Rituximab (BioSim & its evaluation for radioimmunotherapy of relapsed & refractory B-cell non Hodgkins lymphoma patients

    Parul Thakral

    2014-01-01

    Interpretation & conclusions: A favourable radiochemical purity, stability and biodistribution of the radiolabelled immunoconjugate indicate that clinical trials for evaluation of toxicity and efficacy of 177 Lu-DOTA-antiCD20 antibody-Rituximab (BioSim in patients of relapsed and refractory non Hodgkin′s lymphoma can be considered.

  6. Comparison of 90Y/177Lu labeled DOTA-Bz-RGD tetramer and DOTA-RGD tetramer

    90Y/177Lu labeled DOTA-Bz-RGD tetramer and DOTA-RGD tetramer were prepared, and the effect of Bz-DOTA and DOTA on labeling conditions and in vitro stability of radiolabeled compounds was compared. The labeling conditions, including reaction pH, reaction temperature and reaction time, were investigated. ITLC and HPLC show that the labeling yields of four radiolabeled compounds are more than 95% under optimal conditions (pH=6.0, reacting at 100 degree C for 15-20 min); the four radiolabeled compounds show pretty good stability in saline and fetal bovine serum. Although introducing of Bz has no effect on labeling conditions and in vitro stability of radiolabeled compounds, it brings a little change on molecule polarity. HPLC analysis and lg P values reveal that introducing of Bz increases the lipophilicity of radiolabeled compounds. (authors)

  7. Effects of therapy with [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate on endocrine function

    Teunissen, Jaap J.M.; Kwekkeboom, Dik J. [Erasmus Medical Center, Department of Nuclear Medicine, Rotterdam (Netherlands); Krenning, Eric P. [Erasmus Medical Center, Department of Nuclear Medicine, Rotterdam (Netherlands); Erasmus Medical Center, Department of Internal Medicine, Rotterdam (Netherlands); Jong, Frank H. de; Feelders, Richard A.; Aken, Maarten O. van; Herder, Wouter W. de [Erasmus Medical Center, Department of Internal Medicine, Rotterdam (Netherlands); Rijke, Yolanda B. de [Erasmus Medical Center, Department of Clinical Chemistry, Rotterdam (Netherlands)

    2009-11-15

    Peptide receptor radionuclide therapy (PRRT) with radiolabelled somatostatin analogues is a novel therapy for patients with somatostatin receptor-positive tumours. We determined the effects of PRRT with [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate ({sup 177}Lu-octreotate) on glucose homeostasis and the pituitary-gonadal, pituitary-thyroid and pituitary-adrenal axes. Hormone levels were measured and adrenal function assessed at baseline and up to 24 months of follow-up. In 35 men, mean serum inhibin B levels were decreased at 3 months post-therapy (205 {+-} 16 to 25 {+-} 4 ng/l, p < 0.05) and follicle-stimulating hormone (FSH) levels increased (5.9 {+-} 0.5 to 22.7 {+-} 1.4 IU/l, p < 0.05). These levels returned to near baseline levels. Total testosterone and sex hormone binding globulin (SHBG) levels decreased (15.0 {+-} 0.9 to 10.6 {+-} 1.0 nmol/l, p < 0.05 and 61.8 {+-} 8.7 to 33.2 {+-} 3.7 nmol, p < 0.05), respectively, whereas non-SHBG-bound T did not change. An increase (5.2 {+-} 0.6 to 7.7 {+-} 0.7 IU/l, p < 0.05) of luteinizing hormone (LH) levels was found at 3 months of follow-up returning to baseline levels thereafter. In 21 postmenopausal women, a decrease in levels of FSH (74.4 {+-} 5.6 to 62.4 {+-} 7.7 IU/l, p < 0.05) and LH (26.8 {+-} 2.1 to 21.1 {+-} 3.0 IU/l, p < 0.05) was found. Of 66 patients, 2 developed persistent primary hypothyroidism. Free thyroxine (FT{sub 4}) levels decreased (17.7 {+-} 0.4 to 15.6 {+-} 0.6 pmol/l, p < 0.05), whereas thyroid-stimulating hormone (TSH) and triiodothyronine (T{sub 3}) levels did not change. Reverse triiodothyronine (rT{sub 3}) levels decreased (0.38 {+-} 0.03 to 0.30 {+-} 0.01 nmol/l, p < 0.05). Before and after therapy adrenocorticotropic hormone (ACTH) stimulation tests showed an adequate response of serum cortisol (> 550 nmol/l, n = 18). Five patients developed elevated HbA{sub 1c} levels (> 6.5%). In men {sup 177}Lu-octreotate therapy induced transient inhibitory effects on spermatogenesis, but non

  8. Radioimmunotherapy of fungal infection with 213-Bi- and 188-Re-labeled antibody

    Aim: Radioimmunotherapy (RIT) is a therapeutic modality that utilizes monoclonal antibodies (mAb) radiolabeled with therapeutic radioisotopes to selectively deliver lethal doses of radiation to cells. We hypothesized that 18B7 mAb (murine IgG1), specific for Cryptoccocus neoformans (CN) polysaccharide capsule, may be used to deliver fungicidal doses of radioisotopes to the sites of CN infection in vitro and in vivo. Materials and Methods: 18B7 mAb was radiolabeled with either the beta-emitter 188-Rhenium (188Re) or with the alpha-emitter 213-Bismuth (213Bi). The biodistribution of radiolabeled 18B7 was measured in BALB/c mice with and without intratracheal CN infection. For in vitro killing assays 105 CN cells/well were treated with 0-3.2 μCi 213Bi-18B7 (3 h incubation), 32 μCi 188Re-18B7 (48 h incubation) or with radiolabeled IgG1 MOPC21 as a control and minimal inhibitory concentrations (MIC) were determined. To compare the activity of radiolabeled mAb's against CN infection with an established antifungal drug, we evaluated the susceptibility of CN strain to Amphoterecin B. In vivo therapy of CN was conducted in groups of 10 A/JCr mice infected intravenously with 105 CN cells 24 h prior to treatment with 50-200 μCi 213Bi- or 188Re-18B7, 213Bi- or 188Re-MOPC21, unlabeled 18B7 or saline. Student's t test for unpaired data was used to analyze in vitro data, and log-rank test - for animal survival data. Results: MAb 18B7 preserved its immunoreactivity post-labeling and delivered 10% ID/g to the lungs of the CN-infected BALB/c mice in 24 h after injection. Two-log reduction in colony forming units (CFU) was achieved in treatment of CN with 213Bi-18B7 and 188Re-18B7, which compared favorably with Amphoterecin B. MIC's were determined to be 0.4 μCi/1.5 mg and 4 μCi/1.25 mg mAb for 213Bi-18B7 and 188Re-18B7, respectively. The fungicidal activity of irrelevant mAb 213Bi-or 188Re-MOPC21 was negligible (P213Bi-18B7 and of 100 μCi 188Re-18B7 significantly (P<0

  9. Vascular responses to endovascular irradiation of 188Re in the rabbit model after angioplasty

    The effects on vascular restenosis of intravascular radiation delivery from 188Rhenium (Re)-perrhenate liquid-filled balloon through beta-particle radiation are controversial. To determine the effect of beta-radiation on vascular injury in hypercholesterolemic rabbits, thirty rabbits fed with a high cholesterol diet were enrolled into this study. All the rabbits underwent percutaneous transluminal balloon overstretch over left iliac artery. After balloon overstretch, the catheter was withdrawn and immediately followed by irradiation using low dose 188Re solution (10 Gray) in the vascular wall 0.5 mm distal to intimal surface. After 2 and 6 weeks, arteries were harvested for histological and immunological analysis. This rabbit study suggest that endovascular 188Re low dose irradiation at the non-injury segment of iliac artery may enhance intima hyperplasia and smooth muscle cell proliferation. (author)

  10. Synthesis and in Vitro evaluation of ''1''8''8Re-biotinyl-hydrazino-etda

    Pretargeting strategies have overcome many drawbacks associated with the use of directly labelled MoAbs in the diagnosis / treatment of various solid tumors. In particular the avidin-biotin system has received much attention due to extremely high affinity between avidin and biotin. An EDTA derivative of biotin has been synthesized (yield-35%). In order or label biotin derivative (biotinyl-hydrazino-EDTA) , stannous ion was used to reduce ''1''8''8ReO4 (VII) to lower oxidation state and weak chelating agent glucoheptonate as stabilizer and trans chelating agent. Thin layer chromatography and high performance liquid chromatography techniques were employed to monitor the radiolabeling efficiency. The radiolabeling yield of ''1''8''8Re-EDTAB1 was >95%. The radiolabeled product was found to bind to avidin (70-80%), thereby demonstrating retention of its biological integrity

  11. Development of methods of labeling pentavalent DMSA with 99mTc and 188Re

    Technetium-99 m is the most useful radionuclide in diagnostic imaging procedures in Nuclear Medicine, more than 80 percent of radiopharmaceuticals are 99mTc-labeled compounds. 99mTc-DMSA(V) has been used for imaging of soft tissue, head and neck tumors. It shows a particularly high specificity for medullary thyroid carcinoma and bone metastases in a variety of cancers. Biodistribution studies of 188Re-DMSA(V) have shown that its general pharmacokinetic properties are similar to that of 99mTc-DMSA(V), so this agent could be used for targeted radiotherapy of these tumors. The aim of this work is the development of methods of labeling DMSA(V) with 99mTc and 188Re. 99mTc-DMSA(V) can be prepared by two methods. One of them is the indirect one, through the use of a commercial kit of DMSA (III), by adjusting the pH from 2.5 to ∼ 8.5 with NaHCO3. This method was evaluated and optimized presenting high labeling yields. The other method is the direct one, through the preparation of a lyophilised kit ready for labeling with 99mTc, being the method of interest of this work, due to the easy of its clinical use. The most adequate formulation of the kit was: 1.71 mg of DMSA, 0.53 mg of SnCl2.2H2O and 0.83 mg of ascorbic acid (pH 9). Labeling yields higher than 95% were achieved labeling this kit with 1 to 2 m L of 99mTc with activities up to 4736 MBq (128 mCi). The kit was stable up to 6 months and biodistribution studies confirmed the quality of the DMSA (V) labeled with 99mTc using this kit. The reduction potential of Re is lower than the one for Tc, so the labeling conditions of 188Re-DMSA(V) are different from the ones used for 99mTc- DMSA(V). 188Re-DMSA(V) is prepared in acid solution, that makes it possible to use the DMSA (III) commercial kit developed for labeling with 99mTc, prepared in pH 2.5, for labeling with 188Re. Labeling yields higher than 95% were achieved with this methodology, with a rection time of 30 minutes at 100 deg C using no more than 1 m L of 188ReO4

  12. Targeted antisense radiotherapy and dose fractionation using a 177Lu-labeled anti-bcl-2 peptide nucleic acid-peptide conjugate

    Introduction: The overall goal of these studies was to test the hypothesis that simultaneous down-regulation of a tumor survival gene and delivery of internally emitted cytotoxic radiation will be more effective than either treatment modality alone. The objectives were to evaluate the therapeutic efficacy of a 177Lu-labeled anti-bcl-2-PNA-Tyr3-octreotate antisense conjugate in a mouse model bearing human non-Hodgkin’s lymphoma (NHL) tumor xenografts and to optimize targeted antisense radiotherapy by dose fractionation. Methods: In the initial therapy studies, tumor-bearing mice were given saline, nonradioactive DOTA-anti-bcl-2-PNA-Tyr3-octreotate, 177Lu-DOTA-Tyr3-octreotate, 177Lu-DOTA-PNA-peptide alone, or 177Lu-DOTA-PNA-peptide followed by a chase dose of nonradioactive PNA-peptide. The MTD of 177Lu-DOTA-anti-bcl-2-PNA-Tyr3-octreotate was then determined. Subsequently single dose MTD and four weekly fractionated doses were directly compared, followed by histopathologic evaluation. Results: Antisense radiotherapy using 4.44 MBq of the 177Lu-DOTA-PNA-peptide followed by nonradioactive PNA-peptide was significantly more effective than other low dose treatment regimens. A dose of 18.5 MBq of 177Lu-DOTA-PNA-peptide was determined to be the approximate maximum tolerated dose (MTD). The median times to progression to a 1 cm3 tumor volume were 32 and 49 days for single dose MTD and fractionated dose (4 × 4.63 MBq) groups, respectively. Histopathology revealed metastases in the single dose groups, but not in the dose fractionation group. Conclusions: Targeted antisense radiotherapy using 177Lu-DOTA-anti-bcl-2-PNA-Tyr3-octreotate and DOTA-PNA-peptide conjugate effectively inhibited tumor progression in a mouse model of NHL. Furthermore, a dose fractionation regimen had a significant advantage over a single high dose, in terms of tumor growth inhibition and prevention of metastasis. Advances in knowledge and implications for patient care: Down-regulating bcl-2, an anti

  13. Anti-CD45 radioimmunotherapy with 90Y but not 177Lu is effective treatment in a syngeneic murine leukemia model.

    Johnnie J Orozco

    Full Text Available Radioimmunotherapy (RIT for treatment of hematologic malignancies has primarily employed monoclonal antibodies (Ab labeled with 131I or 90Y which have limitations, and alternative radionuclides are needed to facilitate wider adoption of RIT. We therefore compared the relative therapeutic efficacy and toxicity of anti-CD45 RIT employing 90Y and 177Lu in a syngeneic, disseminated murine myeloid leukemia (B6SJLF1/J model. Biodistribution studies showed that both 90Y- and 177Lu-anti-murine CD45 Ab conjugates (DOTA-30F11 targeted hematologic tissues, as at 24 hours 48.8 ± 21.2 and 156 ± 14.6% injected dose per gram of tissue (% ID/g of 90Y-DOTA-30F11 and 54.2 ± 9.5 and 199 ± 11.7% ID/g of 177Lu-DOTA-30F11 accumulated in bone marrow (BM and spleen, respectively. However, 90Y-DOTA-30F11 RIT demonstrated a dose-dependent survival benefit: 60% of mice treated with 300 µCi 90Y-DOTA-30F11 lived over 180 days after therapy, and mice treated with 100 µCi 90Y-DOTA-30F11 had a median survival 66 days. 90Y-anti-CD45 RIT was associated with transient, mild myelotoxicity without hepatic or renal toxicity. Conversely, 177Lu- anti-CD45 RIT yielded no long-term survivors. Thus, 90Y was more effective than 177Lu for anti-CD45 RIT of AML in this murine leukemia model.

  14. 177Lu-EDTMP for palliation of pain from bone metastases in patients with prostate and breast cancer: a phase II study

    The purpose of this study was to evaluate the efficacy and safety of 177Lu-EDTMP for pain palliation in patients with bone metastases from castration-resistant prostate and breast cancer. The secondary objective was to compare low-dose and high-dose 177Lu-EDTMP in bone pain palliation. Included in the study were 44 patients with documented breast carcinoma (12 patients; age 47 ± 13 years) or castration-resistant prostate carcinoma (32 patients; age 66 ± 9 years) and skeletal metastases. Patients were randomized into two equal groups treated with 177Lu-EDTMP intravenously at a dose of 1,295 MBq (group A) or 2,590 MBq (group B). Pain palliation was evaluated using a visual analogue score (VAS), analgesic score (AS) and Karnofsky performance score (KPS) up to 16 weeks. Toxicity was assessed in terms of haematological and renal parameters. The overall response rate (in all 44 patients) was 86 %. Complete, partial and minimal responses were seen in 6 patients (13 %), 21 patients (48 %) and 11 patients (25 %), respectively. A favourable response was seen in 27 patients (84 %) with prostate cancer and in 11 patients (92 %) with breast cancer. There was a progressive decrease in the VAS from baseline up to 4 weeks (p 177Lu-EDTMP was found to be a safe and effective radiopharmaceutical for bone pain palliation in patients with metastatic prostate and breast carcinoma. There were no differences in efficacy or toxicity between patients receiving low-dose and high-dose 177Lu-EDTMP. (orig.)

  15. Synthesis, analysis, purification and biodistribution in an animal model of radiopharmaceutical 177Lu3+ -dotatato for diagnostic and therapeutic use in neuroendocrine tumors

    The aim of this work was to propose rationalization in the synthesis, analysis and purification of radiopharmaceutical 177 Lu3+ - DOTATATO for diagnostic and therapeutic use in neuroendocrine tumors, as well as for evaluation g biodistribution of this radiopharmaceutical an animal-mode. The complexation reaction for the synthesis of radiopharmaceutical was carried out in ammonium acetate buffer 0.5 M, p H 7.0, for 30 minutes at 95 deg C. The radiochemical purity was > 95%, according to analysis by chromatography in ITLC-SG, when using the sodium citrate buffer 0,1 M, p H 5.0, as the mobile phase. The molar-limit ratio 177Lu3+:DOTATATO, in ammonium acetate buffer 0.5 M, p H 7.0, for 30 minutes at 95 deg C, was dependent on the specific activity and origin of the radioisotope, this being 1:3.5 (370 MBq : 26μg) for that from the Oak Ridge National Laboratory /USA, and 1:16 (370 MBq: 11.8 μg) for that from Nuclear Analytical and Medical Services/Holland, when considering a decay of five days from the production date of te radioisotopes. This rationalization in the synthesis of radiopharmaceutical 177Lu3+ - DOTATATO permits high economy in production costs. Chemical studies on the synthesis of radiopharmaceuticals also placed in evidence the interference of 177Hf4+, the decay product of 177Lu3=, as the 177 Lu3= competitor for DOTATATO. Radiopharmaceutical preparation proved to be stable during 24 hours, at an activity rate of 2775 MBq, with the addition of 0.6 mg/mL of gentisic acid and when kept in dry ice. In biodistribution studies on Swiss and Nuce mice, the specificity of radiopharmaceutical for somatostatin positive-receptor tissues, such as the pancreas, stomach, lungs, adrenal glands, kidneys and the cell tumor AR42J was demonstrated. (author)

  16. Somatostatin-receptor-targeted {alpha}-emitting {sup 213}Bi is therapeutically more effective than {beta}{sup -}-emitting {sup 177}Lu in human pancreatic adenocarcinoma cells

    Nayak, Tapan K. [Radiopharmaceutical Sciences Program, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001 (United States); Department of Cell Biology and Physiology, School of Medicine, University of New Mexico, Albuquerque, NM 87131 (United States); Norenberg, Jeffrey P. [Radiopharmaceutical Sciences Program, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001 (United States)]. E-mail: jpnoren@unm.edu; Anderson, Tamara L. [Radiopharmaceutical Sciences Program, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001 (United States); Prossnitz, Eric R. [Department of Cell Biology and Physiology, School of Medicine, University of New Mexico, Albuquerque, NM 87131 (United States); Stabin, Michael G. [Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN 37232 (United States); Atcher, Robert W. [Radiopharmaceutical Sciences Program, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001 (United States); Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2007-02-15

    Introduction: Advance clinical cancer therapy studies of patients treated with somatostatin receptor (sstr)-targeted [DOTA{sup 0}-Tyr{sup 3}]octreotide (DOTATOC) labeled with low-linear-energy-transfer (LET) {beta}{sup -}-emitters have shown overall response rates in the range of 15-33%. In order to improve outcomes, we sought to compare the therapeutic effectiveness of sstr-targeted high-LET {alpha}-emitting {sup 213}Bi to that of low-LET {beta}{sup -}-emitting {sup 177}Lu by determining relative biological effectiveness (RBE) using the external {gamma}-beam of {sup 137}Cs as reference radiation. Methods: Sstr-expressing human pancreatic adenocarcinoma Capan-2 cells and A549 control cells were used for this study. The effects of different radiation doses of {sup 213}Bi and {sup 177}Lu labeled to 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid and sstr-targeted DOTATOC were investigated with a clonogenic cell survival assay. Apoptosis was measured using the Cell Death Detection ELISA{sup PLUS} 10x kit. Results: Using equimolar DOTATOC treatment with concurrent irradiation with a {sup 137}Cs source as reference radiation, the calculated RBE of [{sup 213}Bi]DOTATOC was 3.4, as compared to 1.0 for [{sup 177}Lu]DOTATOC. As measured in terms of absorbance units, [{sup 213}Bi]DOTATOC caused a 2.3-fold-greater release of apoptosis-specific mononucleosomes and oligonucleosomes than [{sup 177}Lu]DOTATOC at the final treatment time of 96 h (P<.001) in sstr-expressing Capan-2 cells. Conclusions: In conclusion, at the same absorbed dose, [{sup 213}Bi]DOTATOC is therapeutically more effective in decreasing survival than is [{sup 177}Lu]DOTATOC in human pancreatic adenocarcinoma cells due to its comparatively higher RBE.

  17. Dosimetry of [177Lu]-DO3A-VS-Cys40-Exendin-4 – impact on the feasibility of insulinoma internal radiotherapy

    Velikyan, Irina; Bulenga, Thomas N; Selvaraju, Ramkumar; Lubberink, Mark; Espes, Daniel; Rosenström, Ulrika; Eriksson, Olof

    2015-01-01

    [68Ga]-DO3A-VS-Cys40-Exendin-4 has been shown to be a promising imaging candidate for targeting glucagon like peptide-1 receptor (GLP-1R). In the light of radiotheranostics and personalized medicine the 177Lu-labelled analogue is of paramount interest. In this study we have investigated the organ distribution of [177Lu]-DO3A-VS-Cys40-Exendin-4 in rat and calculated human dosimetry parameters in order to estimate the maximal acceptable administered radioactivity, and thus potential applicability of [177Lu]-DO3A-VS-Cys40-Exendin-4 for internal radiotherapy of insulinomas. Nine male and nine female Lewis rats were injected with [177Lu]-DO3A-VS-Cys40-Exendin-4 for ex vivo organ distribution study at nine time points. The estimation of human organ/total body absorbed and total effective doses was performed using Organ Level Internal Dose Assessment Code software (OLINDA/EXM 1.1). Six more rats (male: n = 3; female: n = 3) were scanned by single photon emission tomography and computed tomography (SPECT-CT). The renal function and potential cell dysfunction were monitored by creatinine ISTAT and glucose levels. The fine uptake structure of kidney and pancreas was investigated by ex vivo autoradiography. Blood clearance and washout from most of the organs was fast. The kidney was the dose-limiting organ with absorbed dose of 5.88 and 6.04 mGy/MBq, respectively for female and male. Pancreatic beta cells demonstrated radioactivity accumulation. Renal function and beta cell function remained unaffected by radiation. The absorbed dose of [177Lu]-DO3A-VS-Cys40-Exendin-4 to kidneys may limit the clinical application of the agent. However, hypothetically, kidney protection and peptidase inhibition may allow reduction of kidney absorbed dose and amplification of tumour absorbed doses. PMID:25973333

  18. Biological behavior of 188Re-biotin chelate for multistep therapy with the avidin-biotin system

    The purpose of this study was to test the three-step targeting of tumors in mice using biotinylated antibody, streptavidin and radiolabeled biotin for radioimmunotherapy (RAIT). Three-step pretargetting can potentially decreases harmful radiation to normal tissues in radioimmunotherapy. 188Re from 188W-188Re generator, is recently introduced in therapeutic nuclear medicine and made it possible to use whenever needed. We studied biotin-chelates MGB for use in the avidin/biotin pretargetting system. Chelates that hold radiometals with high stability under physiological conditions are essential to avoid excessive radiation damage to non-target cells. We synthesized MAG2GABA-Biocytin (MGB), labeled with 188Re and evaluated biological behavior of 188Re-MGB. biotinyl MAG2GABA bind the therapeutic radiometal 188Re with excellent in vitro stability and have the required physiological properties for pretargetted therapy. In normal mice, 188Re-MGB was excreted via hepatobiliary pathway, %ID/g of GI tract was 52.1 at 120min. In Raji cells tumor bearing nude mice, liver and colon were higher than those of normal mouse. Tumor uptake at 120min was 0.05%ID/g. 188Re-MGB may have a role in pretargetted radioimmunotherapy

  19. Therapeutic Radionuclide Generators: 90Sr/90Y and 188W/188Re Generators

    Radionuclide therapy using radiopharmaceuticals has been in existence for over 60 years and offers substantial benefits to cancer patients, in particular, patients suffering from thyroid cancer. Numerous clinical trials for treating other types of cancer using therapeutic radiopharmaceuticals are in progress, and their success will increase the demand for therapeutic radionuclides in the coming years. Those radioisotopes having short physical half-lives ranging from a few hours to a few days are useful for radionuclide therapy. The use of short lived radioisotopes for radionuclide therapy involves important challenges including the transport of the radionuclides and the need for frequent shipments. Radionuclide generators represent an efficient means for making short lived therapeutic radionuclides more widely available throughout the world. To meet the requirements for sustained growth and future expansion of the application of therapeutic radiopharmaceuticals in nuclear medicine, particularly in oncology, it is important to develop and maintain a constant and reliable supply of therapeutic radionuclides of the required quality in the desired quantities. The IAEA has several activities to support programmes that foster the enhanced availability of therapeutic radionuclides and radiopharmaceuticals in Member States. One such activity was the coordinated research project (CRP) on the development of generator technologies for therapeutic radionuclides, which ran from 2004 to 2007, in which participants from 13 countries worked to develop generator technologies for the preparation of 90Y and 188Re usable for radionuclide therapy. The objectives of the CRP were: (a) To develop reproducible methodologies for the preparation of 90Sr/90Y and 188W/188Re generators; (b) To standardize quality control techniques for generator eluted therapeutic radionuclides; (c) To optimize technologies for post-elution concentration of 188Re; (d) To prepare chromatography adsorbents having

  20. Amifostine protects rat kidneys during peptide receptor radionuclide therapy with [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate

    Rolleman, Edgar J.; Forrer, Flavio; Bernard, Bert; Bijster, Magda; Valkema, Roelf; Krenning, Eric P.; Jong, Marion de [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands); Vermeij, Marcel [Erasmus MC, Department of Pathology, Rotterdam (Netherlands)

    2007-05-15

    In peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues, the kidneys are the major dose-limiting organs, because of tubular reabsorption and retention of radioactivity. Preventing renal uptake or toxicity will allow for higher tumour radiation doses. We tested the cytoprotective drug amifostine, which selectively protects healthy tissue during chemo- and radiotherapy, for its renoprotective capacities after PRRT with high-dose [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate. Male Lewis rats were injected with 278 or 555 MBq [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate to create renal damage and were followed up for 130 days. For renoprotection, rats received either amifostine or co-injection with lysine. Kidneys, blood and urine were collected for toxicity measurements. At 130 days after PRRT, a single-photon emission computed tomography (SPECT) scan was performed to quantify tubular uptake of {sup 99m}Tc-dimercaptosuccinic acid (DMSA), a measure of tubular function. Treatment with 555 MBq [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate resulted in body weight loss, elevated creatinine and proteinuria. Amifostine and lysine treatment significantly prevented this rise in creatinine and the level of proteinuria, but did not improve the histological damage. In contrast, after 278 MBq [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate, creatinine values were slightly, but not significantly, elevated compared with the control rats. Proteinuria and histological damage were different from controls and were significantly improved by amifostine treatment. Quantification of {sup 99m}Tc-DMSA SPECT scintigrams at 130 days after [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate therapy correlated well with 1/creatinine (r {sup 2} = 0.772, p < 0.001). Amifostine and lysine effectively decreased functional renal damage caused by high-dose [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate. Besides lysine, amifostine might be used in clinical PRRT as well

  1. Design and optimization of the production process of radiopharmaceutical 177Lu-DOTA-Nal3-Octreotide for the treatment of gastro-entero-pancreatic tumors

    The radiolabel peptides are molecules of interest in nuclear medicine for their therapeutic and diagnostic application in cancer. Among an impressing group of relevant peptides, those similar of the somatostatin, as the Nal3-Octreotide (NOC), have established as potential radiopharmaceuticals when presenting significant affinity for the receptors of this peptide hormone that are over expressed and broadly distributed in tumors of neuroendocrine origin, as the gastro-entero-pancreatic tumors. On the other hand, the Lutetium-177 (177Lu) is an ideal candidate for the peptides radiolabel and has favorable characteristics to be used in radionuclide therapy. The objective of this work was designing, optimizing and to document the production process of the radiopharmaceutical 177Lu-DOTA-Nal3-Octreotide (177Lu-DOTANOC) for the solicitude of its sanitary registration before the Comision Federal contra Riesgos Sanitarios (COFEPRIS). For the optimization of the production process a factorial design of three variables was evaluated with mixed levels (18 combinations), where the dependent variable is the radiochemical purity and the analytic method used to determine this parameter (High Performance Liquid Chromatography) was validated. Later on, by means of the production of 3 lots of the optimized formula of the radiopharmaceutical 177Lu-DOTANOC the production process was validated and the stability long term study to determine the period of useful life was carried out. The following pharmaceutical formulation was adopted as good: 1.85 GBq (0.5μg) of 177Lu, 250 μg of DOTANOC and 150 μL of acetates Buffer 1 M ph 5 in 5 m L of the medium. The analytic method used to determine the radiochemical purity of the formulation satisfied the requirements for the wished analytic application. We can conclude that the 3 validation lots prepared under protocols of Good Production Practices, in the Plant of Radiopharmaceuticals Production of the Instituto Nacional de Investigaciones

  2. Targeted radionuclide therapy with RAFT-RGD radiolabelled with {sup 90}Y or {sup 177}Lu in a mouse model of αvβ3-expressing tumours

    Bozon-Petitprin, A.; Bacot, S.; Ahmadi, M.; Marti-Batlle, D.; Perret, P.; Broisat, A.; Riou, L.M. [INSERM, U1039, Grenoble (France); Universite de Grenoble, UMR-S1039, Grenoble (France); Gauchez, A.S.; Bourre, J.C.; Fagret, D.; Vuillez, J.P. [INSERM, U1039, Grenoble (France); Universite de Grenoble, UMR-S1039, Grenoble (France); CHRU Grenoble, Hopital Michallon, Service de Medecine Nucleaire, Grenoble (France); Claron, M.; Boturyn, D. [CNRS, UMR 5250, Departement de Chimie Moleculaire, Grenoble (France); Ghezzi, Catherine [INSERM, U1039, Grenoble (France); Universite de Grenoble, UMR-S1039, Grenoble (France); INSERM U1039, Radiopharmaceutiques biocliniques, Batiment Jean Roget, Domaine de la Merci, Faculte de Medecine, La Tronche (France)

    2014-08-28

    The αvβ3 integrin plays an important role in tumour-induced angiogenesis, tumour proliferation, survival and metastasis. The tetrameric RGD-based peptide, regioselectively addressable functionalized template-(cyclo-[RGDfK]){sub 4} (RAFT-RGD), specifically targets the αvβ3 integrin in vitro and in vivo. The aim of this study was to evaluate the therapeutic potential of RAFT-RGD radiolabelled with β{sup -} emitters in a nude mouse model of αvβ3 integrin-expressing tumours. Biodistribution and SPECT/CT imaging studies were performed after injection of {sup 90}Y-RAFT-RGD or {sup 177}Lu-RAFT-RGD in nude mice subcutaneously xenografted with αvβ3 integrin-expressing U-87 MG cells. Experimental targeted radionuclide therapy with {sup 90}Y-RAFT-RGD or {sup 177}Lu-RAFT-RGD and {sup 90}Y-RAFT-RAD or {sup 177}Lu-RAFT-RAD (nonspecific controls) was evaluated by intravenous injection of the radionuclides into mice bearing αvβ3 integrin-expressing U-87 MG tumours of different sizes (small or large) or bearing TS/A-pc tumours that do not express αvβ3. Tumour volume doubling time was used to evaluate the efficacy of each treatment. Injection of 37 MBq of {sup 90}Y-RAFT-RGD into mice with large αvβ3-positive tumours or 37 MBq of {sup 177}Lu-RAFT-RGD into mice with small αvβ3-positive tumours caused significant growth delays compared to mice treated with 37 MBq of {sup 90}Y-RAFT-RAD or 37 MBq of {sup 177}Lu-RAFT-RAD or untreated mice. In contrast, injection of 30 MBq of {sup 90}Y-RAFT-RGD had no effect on the growth of αvβ3-negative tumours. {sup 90}Y-RAFT-RGD and {sup 177}Lu-RAFT-RGD are potent agents targeting αvβ3-expressing tumours for internal targeted radiotherapy. (orig.)

  3. Rhenium-188 Production in Hospitals, by W-188/Re-188 Generator, for Easy Use in Radionuclide Therapy

    Maria Argyrou; Alexia Valassi; Maria Andreou; Maria Lyra

    2013-01-01

    Rhenium-188 (Re-188) is a high energy β-emitting radioisotope obtained from the tungsten-188/rhenium-188 (W-188/Re-188) generator, which has shown utility for a variety of therapeutic applications in nuclear medicine, oncology, and interventional radiology/cardiology. Re-188 decay is accompanied by a 155 keV predominant energy γ-emission, which could be detected by γ-cameras, for imaging, biodistribution, or absorbed radiation dose studies. Its attractive physical properties and its potential...

  4. Novel and efficient preparation of precursor [188Re(OH2)3(CO)3]+ for the labeling of biomolecules.

    Park, Sang Hyun; Seifert, Sepp; Pietzsch, Hans-Jurgen

    2006-01-01

    A novel and efficient method for preparing 188Re(I) tricarbonyl precursor [188Re(OH2)3(CO)3]+ has been developed by reacting [188Re]perrhenate with Schibli's kit in the presence of borohydride exchange resin (BER) as a reducing agent and an anion scavenger. The precursor was produced in more than 97% yield by reacting a solution of tetrahydroborate exchange resin (BER, 3 mg), borane-ammonia (BH3.NH3, 3 mg), and potassium boranocarbonate (K2[H3BCO2], 3 mg) in 0.9% saline with a solution of sodium perrhenate (Na188ReO4) with up to 50 MBq and concentrated phosphoric acid (85%, 7 microL) at 60 degrees C for 15 min. HPLC and TLC revealed 0% unreacted [188Re]perrhenate ion and <3% of colloidal 188ReO2. Since the precursor is produced with high radiochemical purity and labeling efficiency under the milder conditions than those required for the conventional reducing agents, the latter can be replaced. PMID:16417272

  5. Formulation, radiopharmaceutical kinetics and dosimetry of the 188Re(V)-DMSA complex

    It was developed through experimental design (ANOVA), a formulation to prepare the 188 Re(V)-Dmsa complex. Likewise, there were realized studies of radiopharmaceutical kinetics and internal dosimetry in animals, its normal and with induced tumors, considering an open bi compartmental model using the MIRD methodology. The 188 Re(V)-Dmsa complex was obtained with a radiochemical purity greater than 95% incubating 30 min at 90 Centigrade under the following formulation: [SnCl2] = 1.4 mg/ml, [ascorbic acid] = 0.5 mg/ml, p H = 2.0 - 3.0. The stability test of the formulation, shows that after 48 h of its preparation, does not produce radiolytic degradation neither chemical decomposition. The radiopharmaceutical kinetics data show an average residence time 7.2h, velocity constant α = 0.6508h-1 and β = 0.1046 h-1 with an apparent distribution volume 6.9 l. The main elimination via was renal and it was observed osseous caption with an accumulated activity 522.049 ± 62 MBq h (residence time 14.1094 ± 1.69h). In according with the dosimetric calculations, by each 37 MBq injected, the equivalent dose at the tumor was 9.67± 0.33 Sv/g, for an effective dose 0.292 ± 0.0017 mSv/MBq. The images obtained in the gamma camera of the mice with induced tumors, show that do not have significant accumulation in the metabolic organs. The caption in bone and in tumors induced of the 188 Re(V)-Dmsa complex, show its potential for be used as a palliative agent for pain in patients with osseous metastasis and in the treatment of tumors of soft tissue. (Author)

  6. Specific efficacy of peptide receptor radionuclide therapy with 177Lu-octreotate in advanced neuroendocrine tumours of the small intestine

    Increasing evidence supports the value of peptide receptor radionuclide therapy (PRRT) in patients with metastatic neuroendocrine tumours (NET), but there are limited data on its specific efficacy in NET of small intestinal (midgut) origin. This study aims to define the benefit of PRRT with 177Lu-octreotate for this circumscribed entity derived by a uniformly treated patient cohort. A total of 61 consecutive patients with unresectable, advanced small intestinal NET G1-2 stage IV treated with 177Lu-octreotate (4 intended cycles at 3-month intervals, mean activity per cycle 7.9 GBq) were analysed. Sufficient tumour uptake on baseline receptor imaging and either documented tumour progression (n = 46) or uncontrolled symptoms (n = 15) were prerequisites for treatment. Response was evaluated according to modified Southwest Oncology Group (SWOG) criteria and additionally with Response Criteria in Solid Tumors (RECIST) 1.1. Assessment of survival was performed using Kaplan-Meier curves and Cox proportional hazards model for uni- and multivariate analyses. Toxicity was assessed according to standardized follow-up laboratory work-up including blood counts, liver and renal function, supplemented with serial 99mTc-diethylenetriaminepentaacetic acid (DTPA) clearance measurements. The median follow-up period was 62 months. Reversible haematotoxicity (≥ grade 3) occurred in five patients (8.2 %). No significant nephrotoxicity (≥ grade 3) was observed. Treatment response according to modified SWOG criteria consisted of partial response in 8 (13.1 %), minor response in 19 (31.1 %), stable disease in 29 (47.5 %) and progressive disease in 5 (8.2 %) patients. The disease control rate was 91.8 %. Median progression-free survival (PFS) and overall survival (OS) was 33 [95 % confidence interval (CI) 25-41] and 61 months (95 % CI NA), respectively. Objective response was associated with longer survival (p = 0.005). Independent predictors of shorter PFS were functionality [hazard

  7. Outcome of peptide receptor radionuclide therapy with 177Lu-octreotate in advanced grade 1/2 pancreatic neuroendocrine tumours

    The clinical benefit of peptide receptor radionuclide therapy (PRRT) in patients with pancreatic neuroendocrine tumours (pNET) has not yet been well described and defined in its full extent due to limited data in this tumour subgroup. This study was intended to obtain robust, comparative data on the outcome and toxicity of standardized PRRT with 177Lu-octreotate in a well-characterized population of patients with advanced pNET of grade 1/2 (G1/2). We retrospectively analysed a cohort of 68 pNET patients with inoperable metastatic disease consecutively treated with 177Lu-octreotate (four intended cycles at 3-monthly intervals; mean activity per cycle 8.0 GBq). Of these 68 patients, 46 (67.6 %) had documented morphological tumour progression during the 12 months before initiation of treatment, and PRRT was the first-line systemic therapy in 35 patients (51.5 %). Response was evaluated according to modified Southwest Oncology Group (SWOG) criteria and additionally with Response Criteria in Solid Tumors (RECIST) 1.1. Survival was analysed using Kaplan-Meier curves and Cox proportional hazards model for univariate and multivariate analyses. Toxicity was assessed by standard follow-up laboratory work-up including blood count, and liver and renal function, supplemented with serial 99mTc-DTPA clearance measurements. The median follow-up period was 58 months (range 4 - 112). Reversible haematotoxicity (grade 3 or more) occurred in four patients (5.9 %). No significant nephrotoxicity (grade 3 or more) was observed. Treatment responses (SWOG criteria) consisted of a partial response in 41 patients (60.3 %), a minor response in 8 (11.8 %), stable disease in 9 (13.2 %), and progressive disease in 10 (14.7 %). Median progression-free survival (PFS) and overall survival (OS) were 34 (95 % CI 26 - 42) and 53 months (95 % CI 46 - 60), respectively. A G1 proliferation status was associated with longer PFS (p = 0.04) and OS (p = 0.044) in the multivariate analysis. Variables linked

  8. Automation of labelling of Lipiodol with high-activity generator-produced {sup 188}Re

    Lepareur, Nicolas, E-mail: n.lepareur@rennes.fnclcc.f [Service de Medecine Nucleaire, Centre Regional de Lutte Contre le Cancer Eugene Marquis, CS 44229, 35042 Rennes (France); INSERM U-991, Foie, Metabolismes et Cancer, 35033 Rennes (France); Universite Europeenne de Bretagne, Rennes (France); Ardisson, Valerie [Service de Medecine Nucleaire, Centre Regional de Lutte Contre le Cancer Eugene Marquis, CS 44229, 35042 Rennes (France); INSERM U-991, Foie, Metabolismes et Cancer, 35033 Rennes (France); Universite Europeenne de Bretagne, Rennes (France); Noiret, Nicolas [Universite Europeenne de Bretagne, Rennes (France); Ecole Nationale Superieure de Chimie de Rennes, UMR CNRS 6226, Chimie Organique et Supramoleculaire, Avenue du General Leclerc, CS 50837, 35708 Rennes Cedex 7 (France); Boucher, Eveline; Raoul, Jean-Luc [INSERM U-991, Foie, Metabolismes et Cancer, 35033 Rennes (France); Universite Europeenne de Bretagne, Rennes (France); Service d' Oncologie Digestive, Centre Regional de Lutte Contre le Cancer Eugene Marquis, CS 44229, 35042 Rennes (France); Clement, Bruno [INSERM U-991, Foie, Metabolismes et Cancer, 35033 Rennes (France); Garin, Etienne [Service de Medecine Nucleaire, Centre Regional de Lutte Contre le Cancer Eugene Marquis, CS 44229, 35042 Rennes (France); INSERM U-991, Foie, Metabolismes et Cancer, 35033 Rennes (France); Universite Europeenne de Bretagne, Rennes (France)

    2011-02-15

    This work describes optimisation of the kit formulation for labelling of Lipiodol with high-activity generator-produced rhenium-188. Radiochemical purity (RCP) was 92.52{+-}2.3% and extraction yield was 98.56{+-}1.2%. The synthesis has been automated with a TADDEO module (Comecer) giving a mean final yield of 52.68{+-}9.6%, and reducing radiation burden to the radiochemist by 80%. Radiolabelled Lipiodol ({sup 188}Re-SSS/Lipiodol) is stable for at least 7 days (RCP=91.07{+-}0.9%).

  9. The tolerance to 188Re-HEDP treatment in patients with bone pain from osseous metastases

    Objective: To study the tolerance to 188Re-1-hydroxy-1 ,1-ethylidene disodium phosphonate (HEDP) in patients with bone pain caused by osseous metastases. Methods: Thirty-one patients (10 with prostate cancer, 9 with breast cancer, 3 with lung cancer, 5 with liver cancer, 2 with rectal cancer, 1 with esophageal cancer and 1 with renal cancer) received a single injection dose of 188Re-HEDP. The patients were divided into four groups according to the injection dose: 20 MBq/kg (6 patients), 30 MBq/kg(6 patients), 40 MBq/kg (9 patients), and 50 MBq/kg (10 patients). Haematological toxicity (WHO grading) of grade III- IV was considered unacceptable. Vital signs and adverse effects after injection were recorded for 8 weeks. Blood counts were measured weekly during a period of 8 weeks. Biochemical parameters and electrocardiogram were assayed at week 4 and 8. Statistical analysis was performed for per-protocol (pp) population (t-test). Results: Twenty-seven patients belonged to PP population with 5 in the group of 20 MBq/kg, 5 in the group of 30 MBq/kg, 8 in the group of 40 MBq/kg and 9 in the group of 50 MBq/kg. No obvious adverse effects and no significant change of vital signs, electrocardiogram, liver and renal function were found after injection. Alkaline phosphatase was slightly higher than baseline at week 4 and 8 after therapy, but the difference was not statistically significant. In the 20 MBq/kg group, reversible grade I leucopenia was noted in 1 patient. In the 30 MBq/kg group, 2 patients showed reversible grade I leucopenia including 1 alone with reversible grade III thrombopenia. In the 40 MBq/kg group, reversible grade I leucopenia and thrombopenia was observed in 1 patient and reversible grade II leucopenia and thrombopenia in another patient. In the 50 MBq/kg group, 3 patients showed reversible grade II leucopenia. The lowest level of thrombopenia was at week 4(143.5 x 109/L), leucopenia at week 6 (5.4 x 109/L) and anaemia at week 8 (t =3.1325, 3.3156, 3

  10. The Dresden in-stent restenosis radiation trial (DIRRT) with liquid-filled 188Re balloon

    Full text: In some studies intracoronary radiation therapy (IRT) to minimize the restenosis rate after PTCA proved to be effective. We evaluated the performance, safety and effectiveness of IRT with 188Re-perrhenate filled into a standard PTCA balloon. This kind of IRT allows a self-centering homogenous dose distribution to the vessel wall. 107 patients (pts) with a mean age of 63 years (81 m, 26 fin) with in-stent restenosis (type B in 39 %, type C in 61 %) and proven ischemia were included. After routine re-PTCA with or without additional stent implantation a second standard balloon was placed into the PTCA area and filled with β--emitting liquid 188Re at 3 atm. Irradiation time was 525 ± 167 sec to achieve a dose of 30 Gy at 0.5 mm depth of the vessel wall. In only one procedure there was a disconnection of the 188Re containing system and the catheter but no contamination of the cath table or lab was measured. In 16 coronaries 21 stents were additionally implanted. In the follow-up 4 stent thromboses (1 day, 37 days, 2 x 6 months) with subsequent myocardial infarction were noticed, all in pts with additionally implanted stents. 57 pts had control angiography after 4 to 6 months after therapy and 41 after one year. Restenosis (stenosis > 50 % of luminal diameter) was shown in 9 out of 12 pts (75 %) with additionally implanted stents but only in 4 out of 24 pts (17 %) with PTCA alone. Reocclusion was noticed in 3 (25 %) pts with additional stent but only in 1 pt (4 %) without. No re-restenosis occurred in 20 patients which were without finding after 6 months. Intracoronary radiation therapy (IRT) with β--emitting liquid-filled 188Re balloon is a safe and effective therapy method which might be used routinely. Long-term results seem satisfactory in a patient group with in-stent restenosis and high risk of re-restenosis. But the positive effect of irradiation is abolished if an additional stent after PTCA is needed. (author)

  11. Effect of 188Re-IGF-1 analogue in proliferation inhibition and apoptosis induction in pancreatic carcinoma cells

    Objective: To investigate the effect of 188Re-IGF-1 analogue (IGF-1A) in proliferation inhibition and apoptosis induction in human pancreatic carcinoma cell line Patu8988. Methods: IGF-1A was labeled with 188Re. Patu8988 cells were divided into an un-treated control group, IGF-1A group (1, 5, 10, 20 μg), 188ReO4-group (0.37, 1.85, 3.70, 7.40 MBq) and 188Re-IGF-1A group (0.37, 0.74, 1.85 MBq). The cell proliferation inhibition effects by the 188Re-IGF-1A and 188ReO4--were detected every day by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) test from 1 d to 7 d after administration, while the IGF-1 A group was tested every day from 1 d to 6 d after treatment. Inhibition rates were calculated. At 3 d after treatment with 188ReO4-and 188Re-IGF-1A (1.85, 3.70, 7.40 MBq), cell apoptosis was detected by flow cytometry. For biodistribution studies of 188Re-IGF-1A, 36 nude mice bearing Patu8988 cell xenografts were divided into 6 groups. At different time points (15 min, 1 h, 4 h, 1 d, 3 d and 5 d), 36 mice (n=6 per time point) were sacrificed and organs of interest were removed, weighted and measured for radioactivity by a gamma counter. The absorbed doses of organs were calculated as % ID/g. One-way analysis of variance was used. Results: After 4 d, inhibition rate of Patu8988 cell proliferation in the 188Re-IGF-1A group (1.85 MBq) was (90.75 ±5.20)%,higher than that in 188ReO4-group or IGF-1A group ((49.50±2.39)%, (23.00±4.21)%; F=554.724, P<0.01). At 3 d after treatment with different doses of 188Re-IGF-1A (1.85, 3.70, 7.40 MBq), floating cell ratios were (16.56 ± 0.95)%, (33.39 ±5.93)% and (43.76 ± 1.38)%, respectively. Apoptosis ratios in the floating cells treated by 188Re-IGF-1A (1.85, 3.70, 7.40 MBq) were (12.70±2.27)%, (17.80±1.51)% and (23.23 ±1.22)%, respectively. Distribution in tumors was (39.30 ± 17.98), (10.59 ± 9.39), (5.32 ± 1.53) and (5.30 ±2.28)% ID/g at the 15 min, 1 d, 3 d, and 5 d time points after intratumoral

  12. Pharmacokinetics, micro-SPECT/CT imaging and therapeutic efficacy of 188Re-DXR-liposome in C26 colon carcinoma ascites mice model

    The pharmacokinetics and internal radionuclide therapy of intraperitoneally administrated 188Re-N,N-bis(2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA)-labeled pegylated liposomal doxorubicin (188Re-DXR-liposome) were investigated in the C26 murine colon carcinoma ascites mouse model. After intraperitoneal administration of the nanotargeted bimodality 188Re-DXR-liposome, the ascites and tumor accumulation of the radioactivity were observed, the levels of radioactivity within the ascites were maintained at relatively higher levels before 48 h and the levels of radioactivity in the tumor were maintained at steady levels after 4 h. The AUC(o→∞) of 188Re-DXR-liposome in blood, ascites and tumor was 9.3-, 4.2- and 4.7-fold larger than that of 188Re-BMEDA, respectively. The maximum tolerated dose of intraperitoneally administrated 188Re-DXR-liposome was determined in normal BALB/c mice. The survival, tumor and ascites inhibition of mice after 188Re-DXR-liposome (22.2 MBq of 188Re, 5 mg/kg of DXR) treatment were evaluated. Consequently, radiochemotherapeutics of 188Re-DXR-liposome attained better survival time, tumor and ascites inhibition (decreased by 49% and 91% at 4 days after treatment; P188Re-liposome or chemotherapeutics of Lipo-Dox did. Therefore, intraperitoneal administration of novel 188Re-DXR-liposome could provide a benefit and promising strategy for delivery of passive nanotargeted bimodality radiochemotherapeutics in oncology applications

  13. Lessons on Tumour Response: Imaging during Therapy with 177Lu-DOTA-octreotate. A Case Report on a Patient with a Large Volume of Poorly Differentiated Neuroendocrine Carcinoma

    Ulrike Garske, Mattias Sandström, Silvia Johansson, Dan Granberg, Hans Lundqvist, Mark Lubberink, Anders Sundin, Barbro Eriksson

    2012-01-01

    Full Text Available Favourable outcomes of peptide receptor radiotherapy (PRRT of neuroendocrine tumours have been reported during the last years. Still, there are uncertainties on the radionuclides to be used, the treatment planning, and the indication in patients with a high proliferation rate.This case report describes a patient with a high tumour burden of poorly differentiated neuroendocrine carcinoma of unknown primary with a proliferation rate in liver metastases up to 50%, undergoing fractionated treatment with 7 cycles of 177Lu-DOTA-octreotate (7.4 GBq each after disease progression on two different chemotherapy regiments. Based on initial staging scintigraphy, somatostatin receptor expression was very high.Longitudinal dosimetry studies during therapy indicated ongoing increases in tumour-to-organ ratios that coincided with an objective response.We conclude that fractionated therapy with 177Lu-DOTA-octreotate should be considered a treatment option also for those patients with large tumours, high proliferation, and high receptor expression.

  14. Direct in vitro and in vivo comparison of {sup 161}Tb and {sup 177}Lu using a tumour-targeting folate conjugate

    Mueller, Cristina; Reber, Josefine; Haller, Stephanie [Paul Scherrer Institute, Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Villigen (Switzerland); Dorrer, Holger; Tuerler, Andreas [Paul Scherrer Institute, Laboratory of Radiochemistry and Environmental Chemistry, Villigen (Switzerland); University of Bern, Laboratory of Radiochemistry and Environmental Chemistry, Department of Chemistry and Biochemistry, Bern (Switzerland); Bernhardt, Peter [The Sahlgrenska Academy, University of Gothenburg, Department of Radiation Physics, Gothenburg (Sweden); Sahlgrenska University Hospital, Department of Medical Physics and Medical Bioengeneering, Gothenburg (Sweden); Zhernosekov, Konstantin [Paul Scherrer Institute, Laboratory of Radiochemistry and Environmental Chemistry, Villigen (Switzerland); Schibli, Roger [Paul Scherrer Institute, Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Villigen (Switzerland); ETH Zurich, Department of Chemistry and Applied Biosciences, Zurich (Switzerland)

    2014-03-15

    The radiolanthanide {sup 161}Tb (T{sub 1/2} = 6.90 days, Eβ{sup -}{sub av} = 154 keV) was recently proposed as a potential alternative to {sup 177}Lu (T{sub 1/2} = 6.71 days, Eβ{sup -}{sub av} = 134 keV) due to similar physical decay characteristics but additional conversion and Auger electrons that may enhance the therapeutic efficacy. The goal of this study was to compare {sup 161}Tb and {sup 177}Lu in vitro and in vivo using a tumour-targeted DOTA-folate conjugate (cm09). {sup 161}Tb-cm09 and {sup 177}Lu-cm09 were tested in vitro on folate receptor (FR)-positive KB and IGROV-1 cancer cells using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) viability assay. In vivo {sup 161}Tb-cm09 and {sup 177}Lu-cm09 (10 MBq, 0.5 nmol) were investigated in two different tumour mouse models with regard to the biodistribution, the possibility for single photon emission computed tomography (SPECT) imaging and the antitumour efficacy. Potentially undesired side effects were monitored over 6 months by determination of plasma parameters and examination of kidney function with quantitative SPECT using {sup 99m}Tc-dimercaptosuccinic acid (DMSA). To obtain half-maximal inhibition of tumour cell viability a 4.5-fold (KB) and 1.7-fold (IGROV-1) lower radioactivity concentration was required for {sup 161}Tb-cm09 (IC{sub 50} ∝0.014 MBq/ml and ∝2.53 MBq/ml) compared to {sup 177}Lu-cm09 (IC{sub 50} ∝0.063 MBq/ml and ∝4.52 MBq/ml). SPECT imaging visualized tumours of mice with both radioconjugates. However, in therapy studies {sup 161}Tb-cm09 reduced tumour growth more efficiently than {sup 177}Lu-cm09. These findings were in line with the higher absorbed tumour dose for {sup 161}Tb-cm09 (3.3 Gy/MBq) compared to {sup 177}Lu-cm09 (2.4 Gy/MBq). None of the monitored parameters indicated signs of impaired kidney function over the whole time period of investigation after injection of the radiofolates. Compared to {sup 177}Lu-cm09 we demonstrated equal imaging

  15. Prediction of the correct measured activity of 186Re and 188Re from reactor produced natural rhenium using an artificial neural network

    To optimize the cost effectiveness of 186Re and 188Re production, which have recently been used as radio pharmaceuticals for therapeutic purposes, we designed an artificial neural network (ANN) to evaluate the activity of combined 186Re + 188Re. One of the production ways is the (n,γ) reaction of natural rhenium which leads to combined 186Re + 188Re. Using the counted activity of 186Re + 188Re mixtures by a well type isotope calibrator, the precise activity of 186Re and 188Re is obtained by the ANN. A back-propagation ANN was trained using 30 activities of mixed 186Re + 188Re. The performance of the ANN was tested by Early-Stopping validation method, and the ANN was optimized with respect to its architecture. The response of the ANN shows significant precision that may be used for medical application of 186Re + 188Re mixtures.

  16. Ectopic Corticotropin-Producing Neuroendocrine Tumor of the Pancreas Treated With 177Lu DOTATATE Induction and Maintenance Peptide Receptor Radionuclide Therapy.

    Makis, William; McCann, Karey; Riauka, Terence A; McEwan, Alexander J B

    2016-01-01

    A 57-year-old woman diagnosed with ectopic Cushing syndrome was found to have a 111In-octreotide-avid corticotropin-producing pancreatic neuroendocrine tumor with liver metastases. She was treated with 4 induction and 4 maintenance cycles of 177Lu-DOTATATE, which normalized her serum corticotropin levels and dramatically reduced the size of the pancreatic primary and liver metastases. PMID:26359569

  17. Sci—Thur AM: YIS - 03: irtGPUMCD: a new GPU-calculated dosimetry code for {sup 177}Lu-octreotate radionuclide therapy of neuroendocrine tumors

    Montégiani, Jean-François; Gaudin, Émilie; Després, Philippe [Physics, Engineering Physics and Optics, Université Laval, Quebec City, QC (Canada); Jackson, Price A. [Molecular Imaging and Targeted Therapeutics, Peter MacCallum Cancer Centre, Melbourne, VIC (Australia); Beauregard, Jean-Mathieu [Radiology, Université Laval, Quebec City, QC (Canada)

    2014-08-15

    In peptide receptor radionuclide therapy (PRRT), huge inter-patient variability in absorbed radiation doses per administered activity mandates the utilization of individualized dosimetry to evaluate therapeutic efficacy and toxicity. We created a reliable GPU-calculated dosimetry code (irtGPUMCD) and assessed {sup 177}Lu-octreotate renal dosimetry in eight patients (4 cycles of approximately 7.4 GBq). irtGPUMCD was derived from a brachytherapy dosimetry code (bGPUMCD), which was adapted to {sup 177}Lu PRRT dosimetry. Serial quantitative single-photon emission computed tomography (SPECT) images were obtained from three SPECT/CT acquisitions performed at 4, 24 and 72 hours after {sup 177}Lu-octreotate administration, and registered with non-rigid deformation of CT volumes, to obtain {sup 177}Lu-octreotate 4D quantitative biodistribution. Local energy deposition from the β disintegrations was assumed. Using Monte Carlo gamma photon transportation, irtGPUMCD computed dose rate at each time point. Average kidney absorbed dose was obtained from 1-cm{sup 3} VOI dose rate samples on each cortex, subjected to a biexponential curve fit. Integration of the latter time-dose rate curve yielded the renal absorbed dose. The mean renal dose per administered activity was 0.48 ± 0.13 Gy/GBq (range: 0.30–0.71 Gy/GBq). Comparison to another PRRT dosimetry code (VRAK: Voxelized Registration and Kinetics) showed fair accordance with irtGPUMCD (11.4 ± 6.8 %, range: 3.3–26.2%). These results suggest the possibility to use the irtGPUMCD code in order to personalize administered activity in PRRT. This could allow improving clinical outcomes by maximizing per-cycle tumor doses, without exceeding the tolerable renal dose.

  18. Clinical results of radionuclide therapy of neuroendocrine tumours with 90Y-DOTATATE and tandem 90Y/177Lu-DOTATATE: which is a better therapy option?

    Peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues is a treatment option for patients with disseminated neuroendocrine tumours (NET). A combination treatment using the high-energy 90Y beta emitter for larger lesions and the lower energy 177Lu for smaller lesions has been postulated in the literature.The aim of the study was to evaluate combined 90Y/177Lu-DOTATATE therapy in comparison to 90Y-DOTATATE alone. Fifty patients with disseminated NET were included in the study prospectively and divided into two groups: group A (n = 25) was treated with 90Y-DOTATATE, whereas group B (n = 25) received the 1:1 90Y/177Lu-DOTATATE. The administered activity was based on 3.7 GBq/m2 body surface area in three to five cycles, with amino acid infusion for nephroprotection. The median overall survival time in group A was 26.2 months while in group B median survival was not reached. Overall survival was significantly higher in group B (p = 0.027). Median event-free survival time in group A was 21.4 months and in group B 29.4 months (p > 0.1). At the 12-month follow-up, comparison of group A vs group B showed stable disease (SD) in 13 vs 16 patients, disease regression (RD) in 5 vs 3 patients and disease progression (PD) in 3 vs 4 patients; 4 and 2 patients died, respectively. The 24-month follow-up results were SD in nine vs ten patients, RD in one patient vs none and PD in four patients in both groups; three and four patients died, respectively. Side effects were rare and mild. The results indicate that therapy with tandem radioisotopes (90Y/177Lu-DOTATATE) provides longer overall survival than with a single radioisotope (90Y-DOTATATE) and the safety of both methods is comparable. (orig.)

  19. Production of carrier free 188Re radioisotope generator based on aluminum tungstate matrix

    Improved radionuclide generator include a substantially insoluble salt of a radioactive parent which may be directly packed in column for subsequent elution of the daughter radionuclide. An improved 188Re generator was prepared by reacting a radioactive tungsten (188W) as parent radionuclide incorporated with aluminum chloride to obtain an insoluble radioactive aluminum tungstate matrix. The investigated matrix was characterized on the basis of the chemical composition, IR, thermal analysis and mechanical stabilities. The factors affecting the elution performance were studied such as influence of pH, molar ratio and drying temperature. From the obtained data, the molar ratio W:Al was 1.5:1 at pH = 4, the matrix dried at 105 deg C for 2 h. Chromatographic and multichannel analysis has been currently used to investigate the radiochemical and radionuclidic purity respectively on eluted 188Re. An elution yield more than 80%, with radiochemical purity 188W break through >10-4% of the column. The Al+3 and W contents value were about 2 and 3 μg/mL eluate. The obtained data approved the stability of the prepared generator and its suitability for medical application. (author)

  20. PRODUCTION OF CARRIER-FREE 188Re RADIOISOTOPE GENERATOR BASED ON ALUMINUM TUNGSTATE MATRIX

    An improved 188Re generator was prepared by reacting solutions of radioactive tungsten (188 W as parent radionuclide) with aluminum chloride to obtain an insoluble radioactive aluminum tungstate incorporated-188W matrix. The investigated matrix was characterized on the basis of the chemical composition, IR, thermal analysis and physical analysis. The factors affecting the elution performance were studied such as influence of pH, molar ratio and drying temperature. From the obtained data, the W : Al molar ratio was 1.5:1 at pH=4 for the matrix dried at 1050C for 2 hr. Chromatographic and multichannel analysis have been currently used to investigate the radiochemical and radionuclidic purity, respectively, of eluted 188Re. An elution yield more than 80% with radiochemical purity ≥ 98 % and radionuclidic purity ≥ 99.99% with a 188 W break through ≤ 10-4 % of the column tungsten activity. The values of Al3+ and W contents were about 2 and 3μg/ml elute

  1. Radiolabeling and biodistribution of RGD peptide with 188Re-tricarbonyl complex

    Three amino acids residues of Arg-Gly-Asp (RGD) are often the primary site of recognition by integrins which are responsible for tumor invasion and metastasis. In this research, one peptides containing RGD: HCRGD(D)FC were radiolabeled with 188Re-tricarbonyl complex. High radiolabeling ratios (>90%) were achieved under the reaction condition of 75 degree C, 30 min. The radiolabeled peptide got high stability in PBS at room temperature for 4 hours. The hemolysis of red blood cells was not observed during incubation at at 37 degree C for 3 hours. Biodistribution studies were performed in normal male mice and S180-bearing mice, respectively. the radioactivities were rapidly eliminated by the hepatobiliary and urinary systems. Tumor/Muscle ratios were 4.4075 ± 0.1139, 5.1510 ± 0.5375, 4.4727 ± 0.4895 and 4.8788 ± 3.16 at 1h, 4h, 24h and 48h after injection. The results showed that 188Re-tricarbonyl peptide containing RGD was a potential agent for tumor treatment. (authors)

  2. 188Re-labelled anti-CD20 monoclonal antibody: Labelling and quality control studies

    Immunotherapy with human chimeric antibody rituximab (Rituxan, IDEC pharmaceuticals) has been a major advance in treatments of patients with CD20-positive B-cell non Hodgkin's lymphoma (NHL). Radioimmunotherapy (RIT) uses the targeting features of monoclonal antibody to deliver radiation from an attached readionuclide and it is an appeling concept that has received widespread attention. Here, we report our experience using rhenium-188 (188Re)- radiolabeled chimeric anti-CD20 antibody (rituximab). A stable antibody-labeling technique had been developed for 188Re. The 188Re-direct labeling of anti-CD20 monoclonal antibody, the methods for quality control: paper chromatography, instant thin layer chromatographysilica gel (ITLC-SG) and HPLC technique, the immunoreactivity and biological recognition of the target antigen assessment of the radiolabeled molecule, in vitro stability and the assessment of in vivo stability through biodistribution studies in normal WISTAR rats are described. For the direct radiolabeling, the reduction of monoclonal antibody (mAb) was performed with 2-mercaptoethanol (2-ME), based on Schwarz's method at a molar ratio 2000:1 (2- ME:mAb). By means of this method some of the disulfide bonds of the antibody are reduced to sulfhydryl groups (we obtained 4-5 groups) and these groups provide sites for the formation of very strong bond between the reduced rhenium and the antibody. The methodology used in this work has been tested in a phase I radioimmunotherapy clinical trial using the humanized mAb hR3 for loco-regional treatment of brain tumours. The labeling efficiency (> 95 %) of this method showed that the final product needs no further purification for clinical purposes (low level formation of colloidal species). In vitro stability studies of the labeled anti-CD20 were performed at room temperature at 4 h, 24 h and 48 h in cysteine, human serum and saline. In the presence of normal human serum, during the first 4h, transchelation of about 15

  3. Analysis of effectiveness of the palliative treatment of metastatic bone's pain with 188Re-HEDP

    The objective of the study was to evaluate the treatment effectiveness with 188Re-HEDP in a group of 27 patients, who had received 36 doses. A pharmaceutical care programme was also added in order to improve drug follow-up after treatment. Two levels of doses were administered: 30 or 60 mCi. Initially a trace dose was given in order to estimate the therapeutic dose, which was individualise according to bone uptake of the radiopharmaceutical. Bone uptake was determined measuring radioactivity in urine samples (0, 1, 2, 4 and 6 hs), because the radiopharmaceutical showed only renal elimination. Multiple dose schedules with with 3 months between both doses were also tried. Seventy two percent showed an algesic effect during the first week post-treatment, with was kept during one month, while seven tenn (17%) percent of the patients the effect was kept for two of more months. Opioid analgesic (third level of OMS scale) were diminished in eighty two percent of the patients and AINES drugs in seventy one percent. The pharmaceutical care programme also showed the importance of the radio pharmacist role to improve treatment outcomes. 188Re-HEDP effectiveness was achieved in 100% of the patients, but with different pain palliation response in time and/or drug intake, with a suitable radiological safety

  4. Preparation and Preliminary Biological Evaluation of {sup 177}Lu-DOTA folate as Potential Folate Receptor Targeting Therapeutic Agent

    Choi, Kang-Hyuk; Hong, Young-Don; Pyun, Mi-Sun; Lee, So-Young; Felipe, Fenelope; Yoon, Sun-Ha; Choi, Sun-Ju [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2008-10-15

    Folic Acid (FA) and FA derivatives are overexpressed on several tumor cells. The cell-membrane folic acid receptors are known to be responsible for the cellular accumulation of FA and FA analogs, such as methotrexate and folic acid. Folate has been characterized to have high affinity for the folate-receptor positive cells and tissues and considered to be useful as diagnostic imaging and therapeutic agent. In 1940s, Folate analogue, aminopterin, was first used for treatment of leukemia and recently, many folate derivatives were tried for cancer-treatment agent as well as visualization of folate receptor. Many researchers tried to conjugate folic acid with macromolecules or low molecular weight chelators through its alpha or gamma carboxylate. However, despite the reduced binding affinity, FAs are still recognized by the folate receptor. Therefore, we focused to develop folate-based radiopharmaceutical that has the potential to be used as a therapeutic agent. We report here the synthesis and the radiolabeling of {sup 177}Lu-DOTA as well as the biodistribution data of our developed compound.

  5. Synthesis and biological evaluation of 177Lu-DOTA-porphyrin conjugate: a potential agent for targeted tumor radiotherapy

    A novel unsymmetrically substituted water soluble porphyrin derivative namely, 5-(p-aminopropylene-oxyphenyl)-10,15,20-tris-(p-carboxymetylene-oxyphenyl) porphyrin was synthesized and coupled with a bifunctional chelating agent, viz. p-NCS-benzyl-DOTA (p-isothiocyanatobenzyl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) for developing a suitable conjugate for use in targeted tumor therapy. The porphyrin-p-NCS-benzyl-DOTA conjugate was radiolabeled with 177Lu in good radiolabeling yield. Biodistribution studies performed in Swiss mice bearing fibrosarcoma tumors revealed high tumor uptake (5.33±1.11% injected activity per gm of tumor) within 30 min post-injection. The complex exhibited favorable tumor to blood and tumor to muscle ratios at various post-administration time points. Fast clearance of the non-accumulated activity was observed mostly through the renal pathway. Scintigraphic imaging studies performed in Swiss mice bearing fibrosarcoma tumors also exhibited selective accumulation of activity in the tumor.

  6. In-vitro tests of the labeled peptide 177Lu-DOTA-Substance P and evaluation of the dosimetric calculations in the preclinical stage

    Introduction: Substance P (SP) is the main ligand of neurokin type 1 receptors, which are consistently over expressed in malignant gliomas. Method: 177Lu-DOTA-SP was obtained with high radiochemical purity. Biodistribution in normal mice at different times, were done. Absorbed doses were calculated for different mice organs (cGy/μCi). Absorbed doses in human organs were calculated using two different methods, time scaling (A) and data extrapolation (B). Maximum tolerated doses were calculated according to critical organs (mCi/kg). Results: Maximum tolerated dose that can be injected without kidney toxicity is 11,2 mCi/kg (adult man) and 11,4 mCi/kg (adult woman) according to method A and 47,2 mCi/kg, 56,2 mCi/kg, respectively according to method B. Conclusion: So far, 177Lu-DOTA-SP was achieved with a specific activity (S.a) of 0,05 mCi/ μg of peptide. This S.a can be increased using 177LuCl3 of higher specific activity

  7. Alternative chromatographic processes for no-carrier added 177Lu radioisotope separation. Part 1. Multi-column chromatographic process for clinically applicable

    The conventional multi-column solid phase extraction (SPE) chromatography technique using di-(2-ethylhexyl)orthophosphoric acid (HDEHP) impregnated OASIS-HLB sorbent based SPE resins (OASIS-HDEHP) was developed for the separation of no-carrier added (n.c.a) 177Lu from the bulk quantity of ytterbium target. This technique exploited the large variation of lutetium metal ion distribution coefficients in the varying acidity of the HCl solution-OASIS-HDEHP resin systems for the consecutive loading-eluting cycles performed on different columns. The production batches of several hundred mCi n.c.a 177Lu radioisotope separated from 50 mg Yb target activated in a nuclear reactor of medium neutron flux (Φ = 5 x 1013 n x cm-2 x s-1) were successfully performed using the above mentioned separation technique. With the target irradiation in a reactor of thermal neutron flux Φ = 2 x 1014 n x cm-2 x s-1 or the parallel run of several separation units, many Ci-s of n.c.a 177Lu can be profitably produced. The OASIS-HDEHP resin based multi-column SPE chromatography technique makes the separation process simple and economic and offers an automation capability for operation in highly radioactive hazardous environments. (author)

  8. {sup 177}Lu-labeled-VG76e monoclonal antibody in tumor angiogenesis: a comparative study using DOTA and DTPA chelating systems

    Fani, M.; Psimadas, D. [Inst. of Radioisotopes and Radiodiagnostic Products, National Centre for Scientific Research ' ' Demokritos' ' , Athens (Greece); Biomedica Life Sciences S.A., Athens (Greece); Bouziotis, P.; Gourni, E.; Varvarigou, A.D. [Inst. of Radioisotopes and Radiodiagnostic Products, National Centre for Scientific Research ' ' Demokritos' ' , Athens (Greece); Harris, A.L. [Weatherall Inst. of Molecular Medicine, Cancer Research U.K., Univ. of Oxford (United Kingdom); Loudos, G. [Biomedical Simulations and Imaging Lab., National Technical Univ. of Athens (Greece); Maecke, H.R. [Div. of Radiological Chemistry, Univ. Hospital Basel (Switzerland)

    2007-07-01

    Vascular endothelial growth factor (VEGF) is one of the molecules which regulate angiogenesis, a phenomenon observed in many diseases, including cancer. VG76e, an anti-VEGF monoclonal antibody, was labeled with {sup 177}Lu via p-SCN-Bz-DOTA and CHX-A''-DTPA chelating systems, in order to investigate its possible therapeutic use. Labeling was performed by a 30 min incubation of {sup 177}LuCl{sub 3} and each immunoconjugate, at 37 C. Radiochemical analysis showed the formation of a single radioactive species, at a yield higher than 98%, for both immunoconjugates. Kits have been formulated for both VG76e-DOTA and VG76e-DTPA. Stability studies, in the presence of a competitor excess, showed that both radiolabeled species remained sufficiently stable (95%) for at least 48 h. Biodistribution results in normal mice were similar for both radioimmunoconjugates, with no significant bone uptake. Gamma camera images of tumor-bearing mice showed satisfactory visualization of the tumor 24 h p.i., while a higher uptake was observed at 48 h p.i. Our findings indicate that both the bifunctional chelating agents p-SCN-Bz-DOTA and CHX-A''-DTPA can be used for the labeling of VG76e with {sup 177}Lu, with high labeling yield and stability. Their in vivo behaviour in normal and tumor-bearing mice looks promising and they can be successfully used for tumor imaging studies. (orig.)

  9. Biokinetic and dosimetric studies of {sup 188}Re-hyaluronic acid: a new radiopharmaceutical for treatment of hepatocellular carcinoma

    Melendez-Alafort, Laura [Dipartimento di Scienze Farmaceutiche, Universita degli Studi di Padova, 35131 Padua (Italy)], E-mail: laura.melendez@unipd.it; Nadali, Anna; Zangoni, Elena [Dipartimento di Scienze Farmaceutiche, Universita degli Studi di Padova, 35131 Padua (Italy); Banzato, Alessandra; Rondina, Maria [Dipartimento di Scienze Oncologiche e Chirurgiche, Universita degli Studi di Padova, Padua (Italy); Rosato, Antonio [Dipartimento di Scienze Oncologiche e Chirurgiche, Universita degli Studi di Padova, Padua (Italy); Istituto Oncologico Veneto, IOV, Padova, Padua (Italy); Mazzi, Ulderico [Dipartimento di Scienze Farmaceutiche, Universita degli Studi di Padova, 35131 Padua (Italy)

    2009-08-15

    Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has very limited therapeutic options. Recently, it has been found that hyaluronic acid (HA) shows selective binding to CD44 receptors expressed in most cancer histotypes. Since the trend in cancer treatment is the use of targeted radionuclide therapy, the aim of this research was to label HA with rhenium-188 and to evaluate its potential use as a hepatocarcinoma therapeutic radiopharmaceutical. Methods: {sup 188}Re-HA was prepared by a direct labelling method to produce a ReO(O-COO){sub 2}-type coordination complex. {sup 188}Re-HA protein binding and its stability in saline, phosphate buffer, human serum and cysteine solutions were determined. Biokinetic and dosimetric data were estimated in healthy mice (n=60) using the Medical Internal Radiation Dose methodology and mouse model beta-absorbed fractions. To evaluate liver toxicity, alanine aminotranferase (AST) and aspartate aminotranferase (ALT) levels in mice were assessed and the liver maximum tolerated dose (MTD) of {sup 188}Re-HA was determined. Results: A stable complex of {sup 188}Re-HA was obtained with high radiochemical purity (>90%) and low serum protein binding (2%). Biokinetic studies showed a rapid blood clearance (T{sub 1/2}{alpha}=21 min). Four hours after administration, {sup 188}Re-HA was almost totally removed from the blood by the liver due to the selective uptake via HA-specific receptors (73.47{+-}5.11% of the injected dose). The liver MTD in mice was {approx}40 Gy after 7.4 MBq of {sup 188}Re-HA injection. Conclusions: {sup 188}Re-HA complex showed good stability, pharmacokinetic and dosimetric characteristics that confirm its potential as a new agent for HCC radiation therapy.

  10. Biokinetic and dosimetric studies of 188Re-hyaluronic acid: a new radiopharmaceutical for treatment of hepatocellular carcinoma

    Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has very limited therapeutic options. Recently, it has been found that hyaluronic acid (HA) shows selective binding to CD44 receptors expressed in most cancer histotypes. Since the trend in cancer treatment is the use of targeted radionuclide therapy, the aim of this research was to label HA with rhenium-188 and to evaluate its potential use as a hepatocarcinoma therapeutic radiopharmaceutical. Methods: 188Re-HA was prepared by a direct labelling method to produce a ReO(O-COO)2-type coordination complex. 188Re-HA protein binding and its stability in saline, phosphate buffer, human serum and cysteine solutions were determined. Biokinetic and dosimetric data were estimated in healthy mice (n=60) using the Medical Internal Radiation Dose methodology and mouse model beta-absorbed fractions. To evaluate liver toxicity, alanine aminotranferase (AST) and aspartate aminotranferase (ALT) levels in mice were assessed and the liver maximum tolerated dose (MTD) of 188Re-HA was determined. Results: A stable complex of 188Re-HA was obtained with high radiochemical purity (>90%) and low serum protein binding (2%). Biokinetic studies showed a rapid blood clearance (T1/2α=21 min). Four hours after administration, 188Re-HA was almost totally removed from the blood by the liver due to the selective uptake via HA-specific receptors (73.47±5.11% of the injected dose). The liver MTD in mice was ∼40 Gy after 7.4 MBq of 188Re-HA injection. Conclusions: 188Re-HA complex showed good stability, pharmacokinetic and dosimetric characteristics that confirm its potential as a new agent for HCC radiation therapy.

  11. DNA damage in lymphocytes after irradiation with 211At and 188Re. Quantification by alkaline and neutral comet assay

    Aim: Ionising radiation produces many types of DNA lesions of different complexity. High linear energy transfer (LET) types of radiation are biological more effective than low LET radiation. In the present work we applied the single cell gel electrophoreses (comet assay) to study the induction of initial DNA damage, efficiency of repair and residual DNA damage in lymphocytes after treatment with 211At and 188Re. Methods: Peripheral blood mononuclear cells (PBMC) were isolated from heparinized blood of healthy donors and irradiated with 211At and 188Re at different doses. The comet assay was performed under alkaline and neutral conditions in order to detect the initial DNA damage and its repair. The measure of damage was% tail DNA (percentage of DNA in the tail). Results: After treatment of cells with 188Re the initial DNA damage (% tail DNA) detected with the alkaline comet assay was higher than the damage measured for 21lAt. The neutral comet assay estimated higher tail intensities for 211At in contrast to 188Re. Compared with the complete repair (10%) after irradiation with 188Re, the radiotoxicity of alpha particles indicated reduced rejoining of DNA strand breaks (60-80% residual damage). Rejoining of DNA damage measured by the neutral comet method detected about 70% unrepaired strand breaks for 211At and 188Re. Conclusions: There are major differences between the repair of strand breaks caused by 188Re and 211At detected by the alkaline comet assay. The DNA-damage induced by the high LET Emitter 211At remains nearly unrepaired detected by both alkaline and neutral comet assay. Represented data following irradiation of lymphocytes with alpha and beta particles demonstrated higher biological effectiveness of 211At by factors of 2.0-2.5. (orig.)

  12. New peptide receptor radionuclide therapy of invasive cancer cells: in vivo studies using 177Lu-DOTA-AE105 targeting uPAR in human colorectal cancer xenografts

    The proposition of uPAR as a potential target in cancer therapy is advanced by its predominant expression at the invasive front of colorectal cancer (CRC) and its value as prognostic biomarker for poor survival in this disease. In this study, we provide the first in vivo proof-of-concept for a theranostic approach as treatment modality in a human xenograft colorectal cancer model. Methods: A DOTA-conjugated 9-mer high affinity uPAR binding peptide (DOTA-AE105) was radiolabeled with 64Cu and 177Lu, for PET imaging and targeted radionuclide therapy study, respectively. Human uPAR-positive CRC HT-29 cells were inoculated in Nude mice and treated with 177Lu-DOTA-AE105 once a visible tumor had formed. To evaluate the true effect of the targeted radiotherapy, two controls groups were included in this study, one receiving a 177Lu-labeled non-binding control peptide and one receiving vehicle. All animals were treated day 0 and 7. A parallel 18F-FLT PET/CT study was performed on day 0, 1, 3 and 6. Dosimetry calculations were based on a biodistribution study, where organs and tissue of interest were collected 0.5, 1.0, 2.0, 4.0 and 24 h post injection of 177Lu-DOTA-AE105. Toxicity was assessed by recording mouse weight and by H and E staining of kidneys in each treatment group. Results: uPAR-positive HT-29 xenograft was clearly visualized by PET/CT imaging using 64Cu-DOTA-AE105. Subsequently, these xenograft transplants were locally irradiated using 177Lu-DOTA-AE105, where a significant effect on tumor size and the number of uPAR-positive cells in the tumor was found (p 18F-FLT PET/CT imaging study revealed a significant correlation between 18F-FLT tumor uptake and efficacy of the radionuclide therapy. A histological examination of the kidneys from one animal in each treatment group did not reveal any gross abnormalities and the general performance of all treated animals also showed no indications of radioactivity-induced toxicity. Conclusion: These findings document for the

  13. 177Lu-octreotate, alone or with radiosensitising chemotherapy, is safe in neuroendocrine tumour patients previously treated with high-activity 111In-octreotide

    The aim of this retrospective study was to determine whether patients with previous peptide receptor radionuclide therapy using high-activity 111In-pentetreotide can be safely treated with 177Lu-octreotate and whether addition of radiosensitising chemotherapy increases the toxicity of this agent. Records of 27 patients (aged 17-75) who received 69 (median 3 per patient) 177Lu-octreotate administrations, including 29 in conjunction with radiosensitising infusional 5-fluorouracil (5-FU) (n = 27), or capecitabine (n = 2), between October 2005 and July 2007 subsequent to 1-8 prior cycles of 111In-pentetreotide therapy were analysed. Toxicity was assessed during and at 8-12 weeks post-treatment, with further long-term assessments including survival status reviewed till death or study close-out date of 1 November 2009. Reduction in blood counts was most marked following the first dose of 177Lu-octreotate but at early follow-up the only major haematological toxicity was a single case of grade 4 lymphopaenia. Both the presence of bone metastases and the administration of chemotherapy tended to result in greater reduction in blood counts, but these differences did not reach statistical significance. On long-term follow-up, 16 patients (59%) are alive with median overall survival of 36 months (32-44 months from first 177Lu-octreotate therapy). None of the recorded deaths was directly related to treatment toxicity. One patient had late grade 4 anaemia and thrombocytopaenia secondary to bone marrow failure from progressive infiltration by tumour. No other significant long-term haematological toxicities were recorded and no leukaemia was observed. No renal toxicity was observed on serial serum creatinine or radionuclide glomerular filtration rate (GFR) determination on initial or long-term follow-up. 177Lu-octreotate is a safe and well-tolerated therapy for patients who have previously been treated with 111In-pentetreotide and can be safely combined with radiosensitising

  14. {sup 177}Lu-octreotate, alone or with radiosensitising chemotherapy, is safe in neuroendocrine tumour patients previously treated with high-activity {sup 111}In-octreotide

    Hubble, Daniel; Kong, Grace; Michael, Michael; Johnson, Val; Ramdave, Shakher; Hicks, Rodney John [Peter MacCallum Cancer Centre, Centre for Molecular Imaging, East Melbourne, VIC (Australia)

    2010-10-15

    The aim of this retrospective study was to determine whether patients with previous peptide receptor radionuclide therapy using high-activity {sup 111}In-pentetreotide can be safely treated with {sup 177}Lu-octreotate and whether addition of radiosensitising chemotherapy increases the toxicity of this agent. Records of 27 patients (aged 17-75) who received 69 (median 3 per patient) {sup 177}Lu-octreotate administrations, including 29 in conjunction with radiosensitising infusional 5-fluorouracil (5-FU) (n = 27), or capecitabine (n = 2), between October 2005 and July 2007 subsequent to 1-8 prior cycles of {sup 111}In-pentetreotide therapy were analysed. Toxicity was assessed during and at 8-12 weeks post-treatment, with further long-term assessments including survival status reviewed till death or study close-out date of 1 November 2009. Reduction in blood counts was most marked following the first dose of {sup 177}Lu-octreotate but at early follow-up the only major haematological toxicity was a single case of grade 4 lymphopaenia. Both the presence of bone metastases and the administration of chemotherapy tended to result in greater reduction in blood counts, but these differences did not reach statistical significance. On long-term follow-up, 16 patients (59%) are alive with median overall survival of 36 months (32-44 months from first {sup 177}Lu-octreotate therapy). None of the recorded deaths was directly related to treatment toxicity. One patient had late grade 4 anaemia and thrombocytopaenia secondary to bone marrow failure from progressive infiltration by tumour. No other significant long-term haematological toxicities were recorded and no leukaemia was observed. No renal toxicity was observed on serial serum creatinine or radionuclide glomerular filtration rate (GFR) determination on initial or long-term follow-up. {sup 177}Lu-octreotate is a safe and well-tolerated therapy for patients who have previously been treated with {sup 111}In-pentetreotide and can

  15. {sup 177}Lu-EDTMP for palliation of pain from bone metastases in patients with prostate and breast cancer: a phase II study

    Agarwal, Krishan Kant; Singla, Suhas; Arora, Geetanjali; Bal, Chandrasekhar [All India Institute of Medical Sciences, Department of Nuclear Medicine, Ansari Nagar, New Delhi (India)

    2015-01-15

    The purpose of this study was to evaluate the efficacy and safety of {sup 177}Lu-EDTMP for pain palliation in patients with bone metastases from castration-resistant prostate and breast cancer. The secondary objective was to compare low-dose and high-dose {sup 177}Lu-EDTMP in bone pain palliation. Included in the study were 44 patients with documented breast carcinoma (12 patients; age 47 ± 13 years) or castration-resistant prostate carcinoma (32 patients; age 66 ± 9 years) and skeletal metastases. Patients were randomized into two equal groups treated with {sup 177}Lu-EDTMP intravenously at a dose of 1,295 MBq (group A) or 2,590 MBq (group B). Pain palliation was evaluated using a visual analogue score (VAS), analgesic score (AS) and Karnofsky performance score (KPS) up to 16 weeks. Toxicity was assessed in terms of haematological and renal parameters. The overall response rate (in all 44 patients) was 86 %. Complete, partial and minimal responses were seen in 6 patients (13 %), 21 patients (48 %) and 11 patients (25 %), respectively. A favourable response was seen in 27 patients (84 %) with prostate cancer and in 11 patients (92 %) with breast cancer. There was a progressive decrease in the VAS from baseline up to 4 weeks (p < 0.05). Also, AS decreased significantly from 1.8 ± 0.7 to 1.2 ± 0.9 (p < 0.0001). There was an improvement in quality of life of the patients as reflected by an increase in mean KPS from 56 ± 5 to 75 ± 7 (p < 0.0001). The overall response rate in group A was 77 % compared to 95 % in group B (p = 0.188). There was a significant decrease in VAS and AS accompanied by an increase in KPS in both groups. Nonserious haematological toxicity (grade I/II) was observed in 15 patients (34 %) and serious toxicity (grade III/IV) occurred in 10 patients (23 %). There was no statistically significant difference in haematological toxicity between the groups. {sup 177}Lu-EDTMP was found to be a safe and effective radiopharmaceutical for bone pain

  16. Tissue distribution and excretion pattern of 51Cr in animals

    To study distribution and excretion pattern of chromium, 51CrCl3 was orally administered in doses of 66.6 μCi to each rat. Lungs, liver and testis accumulated relatively higher radioactivity earlier and this accumulation persisted in liver and testis for 192 hr. The lungs, heart muscles and gall bladder showed a gradual decline after initial uptake whereas in kidney and spleen it continued to increase as a function of time. Uptake of 51Cr per unit weight of the small intestine was greater than the stomach and the large intestine. On an average, 70.15 percent of the orally administered 51Cr was excreted in faeces within 192 hr of dosing. In the second experiment, six male kids weighing 23.87 kg, on an average, were given orally 500 μCi of 51Cr. Kids were maintained on concentrate mixture and green berseem which contained 0.43 ppm and 0.195 ppm chromium, respectively. The balance studies revealed that 94.93 percent of the total 51Cr dose was excreted in the faeces and 1.93 percent in the urine during 7 day period. Net absorption of 51Cr was, however, only 9.0 percent. (auth.)

  17. A review on the current status and production technology for {sup 188}W-{sup 188}Re generator system

    Kuznetsov, R. A.; Han, H. S.; Cho, W. K.; Park, U. J.; Kim, Y. M

    1998-11-01

    The current status of {sup 188}W-{sup 188}Re generator production technology were reviewed in PART 1. Main interests were given to the aspects of {sup 188}W reactor production, irradiated targets reprocessing and generator loading technologies, such as alumina type and gel type generators. In order to develop the more convenient and advanced {sup 188}W-{sup 188}Re generator, further studies must be carried out to get the precise evaluation of production and burn-up cross section of {sup 188}W, the more easily realizable generator loading procedure, and also to optimize the column and generator design to compensate the deterioration of generator performance because of parent radionuclide decay. By irradiation of {sup 186}W enriched sample, {sup 188}W-{sup 188}Re generator production experiments were performed to evaluate the possibility of {sup 188}W-{sup 188}Re generator production using HANARO, and PART 2 describes about the experiments. The experimental results shows the possibility of practical {sup 188}W-{sup 188}Re generator production using of low-specific activity {sup 188}W produced in HANARO. (author). 79 refs., 4 tabs., 26 figs.

  18. {sup 188}Re-labeled bisphosphonates as potential bifunctional agents for therapy in patients with bone metastases

    El-Mabhouh, Amal [Faculty of Pharmacy and Pharmaceutical Sciences, 3118 Dentistry Pharmacy Center, University of Alberta, Edmonton Alta, T6G-2N8 (Canada); Mercer, John R. [Faculty of Pharmacy and Pharmaceutical Sciences, 3118 Dentistry Pharmacy Center, University of Alberta, Edmonton Alta, T6G-2N8 (Canada); Faculty of Medicine, 3118 Dentistry Pharmacy Center, University of Alberta, Edmonton Alta, T6G-2N8 (Canada)]. E-mail: john.mercer@ualberta.ca

    2005-04-01

    Two new bisphosphonates have been examined for their ability to bind {sup 188}Re and deliver it selectively to bone. The bisphosphonates are prototype compounds with potential to deliver rhenium radionuclides and a second therapy modality to bone metastases. A conjugate between diethylenetriaminepentaacetic acid and bisphosphonate (DTPA/BP) and a conjugate between 5-fluorouracil and bisphosphonate (5-FU/BP) were prepared and labeled at high radiochemical purity with {sup 188}Re and biodistribution studies were carried out in normal Balb/C mice. The compounds showed rapid blood clearance and elimination from soft tissues with substantial retention of activity in the bone comparable to {sup 188}Re-hydroxyethylidine diphosphonate used as a control. At 8 h bone activity was 3.51% of injected dose for {sup 188}Re-DTPA/BP and 6.38% of injected dose for {sup 188}Re-5-FU/BP representing 69.6% and 80.6% of total body radioactivity, respectively. The two compounds show the potential for combination therapy of painful bone metastases.

  19. Synergistic anti-cancer response to chemotherapy and 177Lu-labelled APOMABR radioimmunotherapy in a preclinical model of lung cancer

    Full text of publication follows. Aim: We have identified a murine monoclonal antibody (APOMABR) which targets the La antigen. La is a ribonucleoprotein which is over-expressed in malignancy and is only accessible to antibody binding when tumour cells die, making APOMABR a dead tumour cell-specific marker. We hypothesise that APOMABR radio-labelled with the β-particle emitting radionuclide Lutetium-177 (177Lu) will be an effective anti-tumour treatment in vivo, particular after chemotherapy, as the targeting of radio-labelled APOMABR specifically to dead tumour cells within the tumour tissue will result in the surrounding viable tumour cells being irradiated with a therapeutic dose of β-radiation. Material and Methods: The binding of APOMABR to viable and dead murine Lewis Lung cells (LL2) was examined in vitro by flow cytometry. Subsequently, C57Bl/6 mice bearing syngeneic LL2 tumours were treated with chemotherapy (gemcitabine/cisplatin) and the tumour uptake of biotinylated APOMABR was determined. We then administered escalating activities of 177Lu-labelled APOMABR or a 177Lu-labelled iso-type control antibody either alone or 24 hours after chemotherapy and monitored tumour growth and survival. We also analysed the bio-distribution of 177Lu-labelled APOMABR in LL2 tumour-bearing mice which had or had not been treated with chemotherapy to determine whether the uptake of APOMABR after chemotherapy treatment was tumour-specific. Results: In vitro analysis revealed that APOMABR did not bind viable LL2 cells, but bound with high avidity to cisplatin-treated, dead LL2 cells. Chemotherapy increased tumour cell death in vivo, and was associated with increased tumour uptake of APOMABR compared to LL2 tumour-bearing mice that did not receive chemotherapy. Administration of escalating doses of 177Lu-labelled APOMABR alone to tumour-bearing mice was well tolerated but showed only modest anti-tumour activity which was comparable to the response seen after chemotherapy

  20. Synthesis, characterization and biological evaluation of [{sup 188}Re(N)(cys{approx})(PNP)]{sup +/0} mixed-ligand complexes as prototypes for the development of {sup 188}Re(N)-based target-specific radiopharmaceuticals

    Thieme, Stefan [Institute of Radiopharmacy, Forschungszentrum Dresden Rossendorf, P.O. Box 510 119, 01314 Dresden (Germany); Agostini, Stefania [Department of Pharmaceutical Sciences, University of Padua, Via Marzolo 5, 35131 Padova (Italy); Bergmann, Ralf; Pietzsch, Jens; Pietzsch, Hans-Juergen [Institute of Radiopharmacy, Forschungszentrum Dresden Rossendorf, P.O. Box 510 119, 01314 Dresden (Germany); Carta, Davide; Salvarese, Nicola [Department of Pharmaceutical Sciences, University of Padua, Via Marzolo 5, 35131 Padova (Italy); Refosco, Fiorenzo [ICIS-CNR, Corso Stati Uniti 4, 35127 Padova (Italy); Bolzati, Cristina, E-mail: bolzati@icis.cnr.i [Department of Pharmaceutical Sciences, University of Padua, Via Marzolo 5, 35131 Padova (Italy); ICIS-CNR, Corso Stati Uniti 4, 35127 Padova (Italy)

    2011-04-15

    We report on an efficient procedure for the preparation of [{sup 188}Re(N)(PNP)]-based complexes (where PNP is diphosphinoamine) useful in the development of target-specific radiopharmaceuticals. The radiochemical yield of the compounds was optimized considering such reaction parameters as nature of the nitrido nitrogen donor, reaction times and pH level. The chemical identity of the {sup 188}Re agents was determined by high-performance liquid chromatography comparison with the corresponding well-characterized cold Re compounds. {sup 188}Re(N) mixed compounds have been evaluated with regard to stability toward transchelation with GSH and degradation by serum enzymes. The clearance of selected radiocompounds from normal tissues and their in vivo stability were evaluated in rats by biodistribution and imaging studies. [{sup 188}Re(N)(cys{approx})(PNP)]{sup +/0} mixed-ligand compounds were efficiently prepared in aqueous solution from perrhenate using a multistep procedure based on the preliminary formation of the labile {sup 188}Re{sup III}-EDTA species, which easily undergo oxidation/ligand exchange reaction to afford the [{sup 188}Re{sup V{identical_to}}N]{sup 2+} core in the presence of dithiocarbazate. The final mixed-ligand compounds were obtained, at 100{sup o}C, by adding the two bidentate ligands to the buffered [{sup 188}Re{sup V{identical_to}}N]{sup 2+} solution (pH 3.2-3.6). However, a relatively high amount of cys{approx} ligand was required to obtain a quantitative radiochemical yield. The complexes were stable toward reoxidation to perrhenate and ligand exchange reactions. In vivo studies showed rapid distribution and elimination of the complexes from the body. No specific uptakes in sensitive tissues/organs were detected. A positive correlation of the distribution of the complexes estimated with biodistribution studies (%ID) and with micro-SPECT semiquantification imaging analysis (standard uptake values) was observed. These results support the

  1. Stability of 186Re- and 188Re-DMSAs and removal of impurity in the product

    Complex compound of 186Re- and 188Re with meso-2,3-dimercaptosuccinic acid (DMSA) is expected to be effective against cancerous disease. This compound is synthesized with high radiochemical yield by use of SnCl2 as reducing reagent. However, the product contains a large amount of SnCl2 which is harmful to humans body. The removal of tin impurity was tested with cation exchange resin. 186Re-DMSA complex was also obtained with high radiochemical yield by use of other harmless reducing agents (L-ascorbic acid, Na2-SO3, H3PO3). Synthesized 186Re-DMSA by use of SnCl2 was stable in sodium acetate buffer for 5 hours, while survival amount of 186Re-DMSA synthesized by other reducing agents decreased in a short time. (author)

  2. Radiolabeling RGD-peptide using fac-[188Re(CO)3(H2O)3]+

    Integrin αvβ3 is a member of the integrin family, which plays an important role in angiogenesis and tumour metastasis. The peptides containing arginine-glycine-aspartic acid(RGD) sequence can bind to integrin αvβ3 selectively. In the present study, we labeled two RGD-peptides via fac-[188Re(CO)3(H2O)3]+. The results show that the labeling yields are more than 90% for both of radiolabeled compounds, and they are all stable in phosphate buffered saline and new-born calf serum, even challenged in histidine or cysteine solution. We will evaluate their biological properties to develop radiolabeled agents for tumor therapy. (authors)

  3. Research on labelling chemistry of o-phenanthroline with 99mTc, 188Re and stable Re

    With SnCl2 as reductant, tartrate as intermediate ligand, and with the aid of paper chromatography on three kinds of developing agents, the 99mTc, 188Re and stable rhenium labelling chemistry with regard to o-phenanthroline (Phen) have been studied. The labelling ratio of 99mTc-Phen can reach to 95%. For different pH values of media and at different labelling temperatures, the 99mTc-Phen products cna be different, and they can have different paper chromatographic behavior in some developing agents. The labelling of 188Re and stable rhenium is more difficult than that of 99mTc. Even if large quantity of SnCl2 is used, the labelling ratio of 188Re-phen is significantly lower than 99mTc-Phen: the highest labelling ratio is only 50%

  4. Bifunctional Bisphosphonate Complexes of 99mTc and 188Re for Diagnosis and Therapy of Bone Metastases. Chapter 13

    A simple method to purify the rhenium tricarbonyl precursor for labelling small molecules and biomolecules with 188Re is reported in this chapter. The synthesis of a new radiopharmaceutical for the radionuclide therapy of bone metastases and of the corresponding 99mTc analogue is also described. In contrast with the clinically approved 186/188Re HEDP, this new 188Re agent forms an inert, single species that has been well characterized and displays superior stability, selective bone targeting and retention properties. Similarly, a new bone seeking 99mTc tracer prepared using the 99mTc nitrido core as a prereduced intermediate shows prolonged retention in bone and higher stability and binding to serum proteins compared to 99mTc MDP. (author)

  5. Animal experiment on 188Re-radioactive nanometre particle esophageal stent

    Objective: To investigate the mechanism and clinical reliability of applying 188Re-radioactive nanometre particle esophageal stent. Methods: An elastic meshed esophageal stent made of double membranous nickel-titanium alloy and loaded with 188Re-radioactive nanometre particles was used . The stent was introduced into the esophagus of eight experimental pigs and fixed in place. Two pigs served as controls. With the pig aneasthetized, the stent with good expandability was placed in the proper position. Radioactive MBq was applied to the 8 experiment pigs while the two control pigs received only the stent without the radioactive material. Three hours after the insertion of the stent, the pigs were allowed to feed, without any choking observed. Results: Seven days after the treatment of pathologic experiment pigs showed infla mmatory celluar infilfration, congestion and edema in the mucosa and submucous layer. After 21 days, some parts of the esophageal mucosa showed thickening of the vascular layer of the blood vessels and scanty fibrous hyperplasia. Seven days after application of larger dose of 259 MBq stent, pathology examination carried out in the experiment pigs showed extensive infla mmatory cellular infilfration, edema and congestion in the muscles and submucosa, and patch-like necrosis. Twenty-one days after application, repairing fibrous hyperplasia appeared. In the control pigs, not even any traumatic damage was observed. Periodic checking of the stool did not show any leakage of radioactivity and there was no displacement of the stents as confirmed by X-ray exam. Conclusions: The stent is effective to maintain an unobstructed passage of food . The loaded radioactive particles can be concentrated in the target area and adjusted by a body surface magnetic modulation and inhibit the intraluminal epithelial growth of esophageal mucosa without any severe radiation reaction or damage. It is quite promising to resolve the obstruction of advanced esophageal cancer

  6. 177 Lu-Dota-octreotate radionuclide therapy of advanced gastrointestinal neuroendocrine tumors: results from a phase II study

    Paganelli, Giovanni; Sansovini, Maddalena; Ambrosetti, Alice; Severi, Stefano; Ianniello, Annarita; Matteucci, Federica [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Nuclear Medicine and Radiometabolic Units, Meldola, FC (Italy); Monti, Manuela; Scarpi, Emanuela [IRST IRCCS, Unit of Biostatistics and Clinical Trials, Meldola (Italy); Donati, Caterina [IRST IRCCS, Oncology Pharmacy Laboratory, Meldola (Italy); Amadori, Dino [IRST IRCCS, Department of Medical Oncology, Meldola (Italy)

    2014-10-15

    We evaluated the activity and safety profile of {sup 177}Lu-Dotatate peptide receptor radionuclide therapy (Lu-PRRT) in patients with advanced, well-differentiated (G1-G2) gastrointestinal neuroendocrine tumors (GI-NETs). Forty-three patients with radiological tumor progression at baseline and a positive Octreoscan registered completed the treatment with Lu-PRRT, resulting in the cumulative activity of 18.5 or 27.8 GBq in five cycles. Total activity was scheduled on the basis of kidney function or bone marrow reserve. Twenty-five (58 %) patients were treated with a ''standard'' Lu-PRRT full dosage (FD) of 25.7 GBq (range 22.2-27.8), while the remaining 18 patients (42 %) who, at enrolment, showed a higher probability of developing kidney or bone marrow toxicity received a reduced dosage (RD) of 18.4 GBq (range 14.4-20.4). According to SWOG criteria, the overall response was complete response (CR) in (7 %) cases and stable disease (SD) in 33 (77 %), with a disease control rate (DCR) of 84 %. Median response duration was 25 months (range 7-50). Median progression-free survival (PFS) was 36 months (95 % CI 24-nr), and median overall survival (OS) has not yet been reached. Remarkably, none of the patients, including those at a higher risk of toxicity, showed side-effects after either dosage of Lu-PRRT. Lu-PRRT was shown to be an effective therapeutic option in our patients with advanced progressive GI-NETs, showing an 84 % DCR (95 % CI 73-95) that lasted for 25 months and a PFS of 36 months. Both activities of 27.8 GBq and 18.5 GBq proved safe and effective in all patients, including those with a higher probability of developing kidney or bone marrow toxicity. (orig.)

  7. 177 Lu-Dota-octreotate radionuclide therapy of advanced gastrointestinal neuroendocrine tumors: results from a phase II study

    We evaluated the activity and safety profile of 177Lu-Dotatate peptide receptor radionuclide therapy (Lu-PRRT) in patients with advanced, well-differentiated (G1-G2) gastrointestinal neuroendocrine tumors (GI-NETs). Forty-three patients with radiological tumor progression at baseline and a positive Octreoscan registered completed the treatment with Lu-PRRT, resulting in the cumulative activity of 18.5 or 27.8 GBq in five cycles. Total activity was scheduled on the basis of kidney function or bone marrow reserve. Twenty-five (58 %) patients were treated with a ''standard'' Lu-PRRT full dosage (FD) of 25.7 GBq (range 22.2-27.8), while the remaining 18 patients (42 %) who, at enrolment, showed a higher probability of developing kidney or bone marrow toxicity received a reduced dosage (RD) of 18.4 GBq (range 14.4-20.4). According to SWOG criteria, the overall response was complete response (CR) in (7 %) cases and stable disease (SD) in 33 (77 %), with a disease control rate (DCR) of 84 %. Median response duration was 25 months (range 7-50). Median progression-free survival (PFS) was 36 months (95 % CI 24-nr), and median overall survival (OS) has not yet been reached. Remarkably, none of the patients, including those at a higher risk of toxicity, showed side-effects after either dosage of Lu-PRRT. Lu-PRRT was shown to be an effective therapeutic option in our patients with advanced progressive GI-NETs, showing an 84 % DCR (95 % CI 73-95) that lasted for 25 months and a PFS of 36 months. Both activities of 27.8 GBq and 18.5 GBq proved safe and effective in all patients, including those with a higher probability of developing kidney or bone marrow toxicity. (orig.)

  8. A YAP camera for the biodistribution of 188Re conjugated with Hyaluronic-Acid in 'in vivo' systems

    The aim of the SCINTIRAD experiment is to determine the radio-response of 188Rhenium (Re) in in vitro cells and the biodistribution in different organs of in vivo mice, and subsequently to assess the therapeutic effect on liver tumours induced in mice. Both the γ- and β- emissions of 188Re have been exploited in the experiment. The in vivo biodistribution in mice was studied also with a γ-camera using different parallel hole collimators. In the 188Re spectrum, while the 155 keV γ-peak is useful for imaging, the photons emitted at larger energies and the β-particles act as noise in the image reconstruction. The γ-cameras previously used to image biodistributions obtained with 99Tc are, therefore, not optimized for use with 188Re. A new setup of the γ-camera has been studied for 188Re: 66x66 YAP:Ce crystals (0.6x0.6x10 mm3, 5 μm optical insulation) guarantee a FOV of 40x40 mm2, a Hamamatsu R2486 PSPMT, 3 in. diameter, converts their light into an electrical signal and allows reconstructing the spatial coordinates of the light spot; incoming photon directions are selected through a lead collimator with 1.5 mm diameter hexagonal holes, 0.18 mm septa, 40 mm thickness. Using this setup, results have been obtained both with 99Tc filled and 188Re filled capillaries and wells. The energy spectrum of the collected photons and the spatial resolutions obtainable with the 188Re source will be presented

  9. Evaluating the potential of {sup 188}Re-SOCTA-trastuzumab as a new radioimmunoagent for breast cancer treatment

    Luo, T.-Y. [Isotope Application Division, Institute of Nuclear Energy Research, P.O. Box 3-27, Longtan, Taoyuan 325, Taiwan (China)], E-mail: tylo@iner.gov.tw; Tang, I-C.; Wu, Y.-L.; Hsu, K.-L. [Isotope Application Division, Institute of Nuclear Energy Research, P.O. Box 3-27, Longtan, Taoyuan 325, Taiwan (China); Liu, S.-W. [Chemistry Division, Institute of Nuclear Energy Research, Taoyuan 325, Taiwan (China); Kung, H.-C. [Department of Electrical Engineering, Tung Nan University, Taipei 222, Taiwan (China); Lai, P.-S. [Department of Chemistry, National Chung Hsing University, Taichung 402, Taiwan (China); Lin, W.-J. [Isotope Application Division, Institute of Nuclear Energy Research, P.O. Box 3-27, Longtan, Taoyuan 325, Taiwan (China)

    2009-01-15

    Introduction: Radioimmunotherapy, which utilizes monoclonal antibodies and therapeutic radioisotopes against antigen-expressing tumor tissues, is an attractive therapeutic approach for cancer therapy. Trastuzumab (Herceptin) is a humanized anti-HER-2/neu monoclonal antibody for breast cancer treatment. In this paper, we introduce a new radioimmunoagent, {sup 188}Re-trastuzumab, via a bifunctional ligand, succinimidyl 3,6-diaza-5-oxo-3-[2-((triphenylmethyl)thio)ethyl] -8-[(triphenylmethyl)thio]octanoate (SOCTA), and evaluate its potential to be a therapeutic radiopharmaceutical for breast cancer treatment. Methods: Equimolar amounts of SOCTA and trastuzumab were selected to react, and the conjugation ratio of SOCTA-trastuzumab was evaluated by the MALDI-TOF method. The immunoreactivity of SOCTA-trastuzumab was compared with nonconjugated trastuzumab in HER-2/neu overexpressing human breast cancer cell BT-474. Biodistribution experiment and microSPECT/CT images of {sup 188}Re-SOCTA-trastuzumab being administered intravenously to SCID mice bearing xenografted BT-474 breast cancer were investigated to evaluate the tumor-targeting capability. Results: The covalent attachment of SOCTA to trastuzumab (at 1:1 molar ratio) resulted in the averaged conjugation ratio of 0.27{+-}0.06 (n=3). The complex could easily be labeled with {sup 188}Re and achieve 95% radiochemical purity (RCP) after 1 h of reaction at room temperature. The in vitro stability study also revealed that the RCP of {sup 188}Re-SOCTA-trastuzumab was at a value of more than 85% after 48 h of incubation with human serum. The immunoreactivity evaluation showed that SOCTA-trastuzumab and nonconjugated trastuzumab had similar binding capacity (B{sub max}) to HER-2/neu receptor in BT-474 cells. The animal experiments showed that {sup 188}Re-SOCTA-trastuzumab accumulated more intensively in the tumor site as compared to normal tissue. Conclusion: We suggest that {sup 188}Re-SOCTA-trastuzumab could be a potential

  10. Design and optimization of the production process of radiopharmaceutical {sup 177}Lu-DOTA-Nal{sup 3}-Octreotide for the treatment of gastro-entero-pancreatic tumors; Diseno y optimizacion del proceso de produccion del radiofarmaco {sup 177}Lu-DOTA-Nal{sup 3}-Octreotido para el tratamiento de tumores gastroenteropancreaticos

    Sanchez G, M. F.

    2013-07-01

    The radiolabel peptides are molecules of interest in nuclear medicine for their therapeutic and diagnostic application in cancer. Among an impressing group of relevant peptides, those similar of the somatostatin, as the Nal{sup 3}-Octreotide (NOC), have established as potential radiopharmaceuticals when presenting significant affinity for the receptors of this peptide hormone that are over expressed and broadly distributed in tumors of neuroendocrine origin, as the gastro-entero-pancreatic tumors. On the other hand, the Lutetium-177 ({sup 177}Lu) is an ideal candidate for the peptides radiolabel and has favorable characteristics to be used in radionuclide therapy. The objective of this work was designing, optimizing and to document the production process of the radiopharmaceutical {sup 177}Lu-DOTA-Nal{sup 3}-Octreotide ({sup 177}Lu-DOTANOC) for the solicitude of its sanitary registration before the Comision Federal contra Riesgos Sanitarios (COFEPRIS). For the optimization of the production process a factorial design of three variables was evaluated with mixed levels (18 combinations), where the dependent variable is the radiochemical purity and the analytic method used to determine this parameter (High Performance Liquid Chromatography) was validated. Later on, by means of the production of 3 lots of the optimized formula of the radiopharmaceutical {sup 177}Lu-DOTANOC the production process was validated and the stability long term study to determine the period of useful life was carried out. The following pharmaceutical formulation was adopted as good: 1.85 GBq (0.5μg) of {sup 177}Lu, 250 μg of DOTANOC and 150 μL of acetates Buffer 1 M ph 5 in 5 m L of the medium. The analytic method used to determine the radiochemical purity of the formulation satisfied the requirements for the wished analytic application. We can conclude that the 3 validation lots prepared under protocols of Good Production Practices, in the Plant of Radiopharmaceuticals Production of the

  11. Development of a 188W/188Re Generator, Post-Elution Concentration of 99mTc and Evaluation of High Capacity Adsorbents

    The objective of the coordinated research project was the development of techniques for the preparation of 90Sr/90Y and 188W/188Re generators. The research at IPEN-CNEN/SP focused on developing a generator technology using high specific activity 188W imported from the Russian Federation. The development of a 188Re gel type generator, using the experience acquired by IPEN in recent years through the 99mTc gel generator project, is discussed. Quality control procedures were developed to ensure the purity of the eluted 188Re, and special attention was given to post-elution concentration of 188Re. (author)

  12. 188Re-HTDD-lipiodol solution as a new therapeutic agent for transhepatic arterial administration in liver cancer: a preclinical study using liver-cancer model in rabbit

    188Re-HTDD-lipiodol solution was developed and reported to be a new therapeutic material for transhepatic arterial embolization (TAE) of liver cancer. In this study we compared the tissue retention of 188Re-HTDD-lipiodol with that of 188Re-TDD-lipiodol using liver-cancer model in rabbit. Cancer cell line VX2 was inoculated into 7 rabbits and grown up to larger than 3 cm. TAE was performed with 188Re-TDD-lipiodol in 3 rabbits and with 188Re-HTDD-lipiodol in 4 rabbits. Conjugated planar scans were performed at 1, 2, 6, 24, 48 hours after TAE. From these images, the mean life of radioactivity retention in tumor was calculated, and the required dose for human application as also calculated from the mean life and MIRDOSE3 software. The mean lifes of radioactivity in liver were 10.2±1.0 hr in TDD group and 17.6±0.8 hr in HTDD group (p188Re-HTDD-lipiodol for 5.7 cm-sized tumor and 88 mCi for 9,7 cm-sized tumor. By the introduction of long chain alkyl group, 188Re-HTDD-lipiodol showed significantly better tumor retention than that of 188Re-TDD-lipiodol. And the required dose of radiation for human application was calculated to be 18 ∼ 88 mCi when using 188Re-HTDD-lipiodol

  13. Pharmacokinetics, micro-SPECT/CT imaging and therapeutic efficacy of (188)Re-DXR-liposome in C26 colon carcinoma ascites mice model.

    Chen, Liang-Cheng; Chang, Chih-Hsien; Yu, Chia-Yu; Chang, Ya-Jen; Wu, Yu-Hsien; Lee, Wan-Chi; Yeh, Chung-Hsin; Lee, Te-Wei; Ting, Gann

    2008-11-01

    The pharmacokinetics and internal radionuclide therapy of intraperitoneally administrated (188)Re-N,N-bis(2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA)-labeled pegylated liposomal doxorubicin ((188)Re-DXR-liposome) were investigated in the C26 murine colon carcinoma ascites mouse model. After intraperitoneal administration of the nanotargeted bimodality (188)Re-DXR-liposome, the ascites and tumor accumulation of the radioactivity were observed, the levels of radioactivity within the ascites were maintained at relatively higher levels before 48 h and the levels of radioactivity in the tumor were maintained at steady levels after 4 h. The AUC((o-->infinity)) of (188)Re-DXR-liposome in blood, ascites and tumor was 9.3-, 4.2- and 4.7-fold larger than that of (188)Re-BMEDA, respectively. The maximum tolerated dose of intraperitoneally administrated (188)Re-DXR-liposome was determined in normal BALB/c mice. The survival, tumor and ascites inhibition of mice after (188)Re-DXR-liposome (22.2 MBq of (188)Re, 5 mg/kg of DXR) treatment were evaluated. Consequently, radiochemotherapeutics of (188)Re-DXR-liposome attained better survival time, tumor and ascites inhibition (decreased by 49% and 91% at 4 days after treatment; Ppassive nanotargeted bimodality radiochemotherapeutics in oncology applications. PMID:19026950

  14. Somatostatin receptor expression in the human spleen - Answer to an enigma by ex-vivo and in-vitro autoradiography after 177Lu-DOTA-octreotate administration

    Full text of publication follows. Aim: radiolabelled somatostatin analogues are being used for diagnostic and therapeutic (PRRT) purposes in patients with somatostatin receptor (SSTR) expressing tumours. During PRRT a significant spleen uptake may lead to radiation doses of > 20 Gy. Yet, the threshold dose for spleen radiation induced toxicity is currently unknown. Based on previous 68Ga-DOTATOC PET/CT studies, demonstrating higher uptake in spleen than in splenosis, white pulp (WP) localization of radioactivity was suggested. This hypothesis was investigated in the current pilot study using the longer lived 177Lu-DOTA-octreotate. Methods: a patient diagnosed with neuroendocrine neoplasm of the pancreatic tail (SUVmax on 68Ga-DOTATOC PET/CT 100.4) with liver metastasis (SUV 47.3, normal liver SUV 12.5) and uptake in the spleen (SUV 41.0) received 1 GBq 177Lu-DOTA-octreotate. 2 h after administration whole-body planar scintigraphy and SPECT/CT of the upper abdomen was performed, followed by laparoscopic resection of the pancreatic tumour and splenectomy the next day. After spleen transport from Bad Berka to Rotterdam ex-vivo micro-SPECT of the removed spleen was acquired for 73 min using 2.5 mm diameter pinholes. Spleen fragments (∼10 * 10 * 5 mm) were either snap-frozen in liquid nitrogen or fixed in 10% formalin and paraffin embedded. Ex-vivo autoradiography of 10 μm cryo-sections was performed and serial sections were used for 111In-DOTA-octreotate in-vitro autoradiography after decay of 177Lu. FFPE sections were used for HE- and immunostaining for SSTR2A and cell subsets CD4 (Th-cell), CD8 (Ts-cell), CD20 (B-cell) and CD68 (macrophage). Results: 177Lu-DOTA-octreotate scintigraphy and SPECT/CT demonstrated high uptake in the pancreatic tumor, hepatic metastasis and homogeneously in the normal spleen. High resolution micro-SPECT imaging of the isolated spleen also revealed a relatively homogeneous uptake (calculated rest activity 60 MBq 177Lu). The vast

  15. Nuclear model calculations on cyclotron production of 51Cr

    51Cr (T1/2 = 27.7 d), which decays via electron capture (100 %) with 320 keV gamma emission (9.8 %), is a radionuclide with still a large application in biological studies. In this work, ALICE/ASH and TALYS nuclear model codes along with some adjustments are used to calculate the excitation functions for proton, deuteron, α-particle and neutron induced on various targets leading to the production of 51Cr radioisotope. The production yields of 51Cr from various reactions are determined using the excitation function calculations and stopping power data. The results are compared with corresponding experimental data and discussed from point of view of feasibility.

  16. Nuclear model calculations on cyclotron production of {sup 51}Cr

    Kakavand, Tayeb [Imam Khomeini International Univ., Qazvin (Iran, Islamic Republic of). Dept. of Physics; Aboudzadeh, Mohammadreza [Nuclear Science and Technology Research Institute/AEOI, Karaj (Iran, Islamic Republic of). Agricultural, Medical and Industrial Research School; Farahani, Zahra; Eslami, Mohammad [Zanjan Univ. (Iran, Islamic Republic of). Dept. of Physics

    2015-12-15

    {sup 51}Cr (T{sub 1/2} = 27.7 d), which decays via electron capture (100 %) with 320 keV gamma emission (9.8 %), is a radionuclide with still a large application in biological studies. In this work, ALICE/ASH and TALYS nuclear model codes along with some adjustments are used to calculate the excitation functions for proton, deuteron, α-particle and neutron induced on various targets leading to the production of {sup 51}Cr radioisotope. The production yields of {sup 51}Cr from various reactions are determined using the excitation function calculations and stopping power data. The results are compared with corresponding experimental data and discussed from point of view of feasibility.

  17. Multimodal Somatostatin Receptor Theranostics Using [64Cu]Cu-/[177Lu]Lu-DOTA-(Tyr3)octreotate and AN-238 in a Mouse Pheochromocytoma Model

    Ullrich, Martin; Bergmann, Ralf; Peitzsch, Mirko; Zenker, Erik F.; Cartellieri, Marc; Bachmann, Michael; Ehrhart-Bornstein, Monika; Block, Norman L.; Schally, Andrew V.; Eisenhofer, Graeme; Bornstein, Stefan R.; Pietzsch, Jens; Ziegler, Christian G.

    2016-01-01

    Pheochromocytomas and extra-adrenal paragangliomas (PHEO/PGLs) are rare catecholamine-producing chromaffin cell tumors. For metastatic disease, no effective therapy is available. Overexpression of somatostatin type 2 receptors (SSTR2) in PHEO/PGLs promotes interest in applying therapies using somatostatin analogs linked to radionuclides and/or cytotoxic compounds, such as [177Lu]Lu-DOTA-(Tyr3)octreotate (DOTATATE) and AN-238. Systematic evaluation of such therapies for the treatment of PHEO/PGLs requires sophisticated animal models. In this study, the mouse pheochromocytoma (MPC)-mCherry allograft model showed high tumor densities of murine SSTR2 (mSSTR2) and high tumor uptake of [64Cu]Cu-DOTATATE. Using tumor sections, we assessed mSSTR2-specific binding of DOTATATE, AN-238, and somatostatin-14. Therapeutic studies showed substantial reduction of tumor growth and tumor-related renal monoamine excretion in tumor-bearing mice after treatment with [177Lu]Lu-DOTATATE compared to AN-238 and doxorubicin. Analyses did not show agonist-dependent receptor downregulation after single mSSTR2-targeting therapies. This study demonstrates that the MPC-mCherry model is a uniquely powerful tool for the preclinical evaluation of SSTR2-targeting theranostic applications in vivo. Our findings highlight the therapeutic potential of somatostatin analogs, especially of [177Lu]Lu-DOTATATE, for the treatment of metastatic PHEO/PGLs. Repeated treatment cycles, fractionated combinations of SSTR2-targeting radionuclide and cytotoxic therapies, and other adjuvant compounds addressing additional mechanisms may further enhance therapeutic outcome. PMID:27022413

  18. Thermodynamic evaluation of the stability of the bone-seeking radiopharmaceutical [177Lu]Lu(III)–DOTP under simulated blood plasma conditions

    Highlights: ► Thermodynamic blood plasma model supports in vivo biodistribution of [177Lu]Lu–DOTP. ► Lu3+ remains predominantly complexed (98.1%) with the DOTP under simulated physiological conditions. ► Thermodynamic and kinetic stability [177Lu]Lu–DOTP in blood plasma facilitates selectivity of the proposed radiopharmaceutical for bone. - Abstract: The stability and in vivo robustness of [177Lu]Lu–DOTP as a potential bone-targeting radiopharmaceutical was determined with the aid of thermodynamic blood plasma modeling simulations. Glass electrode potentiometry was employed to measure the stability constants of the complexes of Lu3+ with DOTP. Similarly, the complexes of DOTP with a selection of the important physiological metal ions: Ca2+, Mg2+, and Cu2+ were determined, representing the typical interactions that the ligand would encounter upon administration. This made possible the construction of a blood plasma model of DOTP, aiding in establishing the potential susceptibility of the radiopharmaceutical. The ligand binds predominantly to calcium in vivo, accounting for 59.6% of that initially introduced as a component of the Lu–DOTP complex. Furthermore, due to a preference of the DOTP to bind to Cu2+ it causes mobilization of the ions in blood plasma, and would therefore indicate a deficiency if the ligand is administered at a concentration of 8.5 × 10−5 mol dm−3. The lutetium-ions are preferentially bound to DOTP, with as much as 98.1% of the Lu3+ occupying the ligand under physiological conditions.

  19. The efficacy of {sup 177}Lu-labelled peptide receptor radionuclide therapy in patients with neuroendocrine tumours: a meta-analysis

    Kim, Seong-Jang; Pak, Kyoungjune [Pusan National University Hospital, Department of Nuclear Medicine and Biomedical Research Institute, Busan (Korea, Republic of); Koo, Phillip J.; Kwak, Jennifer J.; Chang, Samuel [University of Colorado School of Medicine, Department of Radiology, Aurora, CO (United States)

    2015-12-15

    This study was performed to evaluate the efficacy of {sup 177}Lu-labelled peptide receptor radionuclide therapy (PRRT) in patients with inoperable or metastatic neuroendocrine tumours (NETs). Systematic searches of MEDLINE and EMBASE databases were performed using the keywords of ''neuroendocrine'', ''{sup 177}Lu'' and ''prognosis''. All published studies of neuroendocrine tumours treated with {sup 177}Lu-labelled radiopharmaceuticals and evaluated with either Response Evaluation Criteria in Solid Tumours (RECIST) 1.0 or Southwest Oncology Group (SWOG) criteria or both were included. If there was more than one published study from the same institution, only one report with the information most relevant to this study was included. Each response criteria group was analysed for disease response rates and disease control rates, defined as the percentages of patients with complete response (CR) + partial response (PR), and CR + PR + stable disease (SD), respectively, to a therapeutic intervention in clinical trials of anticancer agents. The pooled proportions are presented with both a fixed-effects model and random-effects model. Six studies with 473 patients (4 in RECIST criteria group with 356 patients, 3 in SWOG criteria group with 375 patients and 1 in both groups) were included. The RECIST criteria group demonstrated disease response rates ranging between 17.6 and 43.8 % with a pooled effect of 29 % [95 % confidence interval (CI) 24-34 %]. Disease control rates ranged from 71.8 to 100 %. The random-effects model showed an average disease control rate of 81 % (95 % CI 71-91 %). The SWOG criteria group demonstrated disease response rates ranging between 7.0 and 36.5 % with a pooled effect of 23 % (95 % CI 11-38 %). Disease control rates ranged from 73.9 to 89.1 %. The random-effects model showed an average disease control rate of 82 % (95 % CI 71-91 %). {sup 177}Lu-labelled PRRT is an effective treatment

  20. Specific energy from Auger and conversion electrons of 131I, 188Re-anti-CD20 to a lymphocyte's nucleus

    Torres-García, E.; Carrillo-Cazares, T. A.

    2011-01-01

    The typical radionuclides used to label anti-CD20 in the treatment of non-Hodgkin's lymphoma are 90Y, 131I, and 188Re, with the emission of beta particles, Auger electrons, and conversion electrons for the latter two. The aim of the present work was to calculate the contribution of high linear energy transfer radiation as Auger electrons (AE) and conversion electrons (CE) of 131I and 188Re-anti-CD20 to mean specific energy into the cell nucleus by Monte Carlo simulation (MCS), so as to infer therapeutic effectiveness on a dosimetric basis. MCS was used to quantify the frequency-mean specific energy into the cell nucleus, where the cell was modeled by two concentric spheres, considering two cell models. The results showed that 10% and 33% of the mean-specific energies (z¯) per disintegration imparted to the cell nucleus for both geometries are due to AE and CE; on the other hand, if the hit of AE and CE occurs, the contribution to (z¯) is about 64% and 86% for 131I and 188Re, respectively. According to the amount of specific energy from AE and CE into the cell nucleus by positive event, they can cause catastrophic effects in the nuclear DNA in the treatment of non-Hodgkin's lymphoma with 131I, 188Re-anti-CD20.

  1. Intravascular β-irradiation with a liquid 188Re-filled balloon for the prevention of restenosis in rabbit model

    Objective: To investigate the effects of intravascular β-irradiation with a liquid 188Re-filled balloon on restenosis in rabbit model, and to evaluate the feasibility of the intravascular irradiation. Methods: The bilateral iliac arteries of 14 rabbits were injured by catheter balloon overdilation. A random side iliac artery of the rabbit was irradiated by a liquid 188Re-filled balloon with the radioactivity of 15 Gy at a depth of 0.5 mm beneath the skin close to the artery, and the other iliac artery served as a control. At 12 weeks after operation, quantitative angiography, histopathology and immunohistochemistry analysis were performed in the injured iliac arteries to evaluate the effects of irradiation. Results: There was significant increase in iliac artery diameter [(1.94 +- 0.19) vs (1.77 +- 0.28) mm, P2, P188Re-filled balloon irradiation group compared with control group. Conclusions: Intravascular β-irradiation by a liquid 188Re-filled balloon with 15 Gy at 0.5 mm tissue depth beneath the skin close to the artery in rabbit model could inhibit neointimal proliferation and prevent restenosis. The intravascular brachytherapy with irradiation for prevention of restenosis is technically feasible

  2. Pharmacokinetics, micro-SPECT/CT imaging and therapeutic efficacy of {sup 188}Re-DXR-liposome in C26 colon carcinoma ascites mice model

    Chen, L.-C.; Chang, C.-H.; Yu, C.-Y.; Chang, Y.-J.; Wu, Y.-H.; Lee, W.-C.; Yeh, C.-H.; Lee, T.-W. [Institute of Nuclear Energy Research, Taoyuan, Taiwan (China); Ting Gann [National Institute of Cancer Research, National Health Research Institutes, Miaoli, Taiwan (China)], E-mail: gann.ting@msa.hinet.net

    2008-11-15

    The pharmacokinetics and internal radionuclide therapy of intraperitoneally administrated {sup 188}Re-N,N-bis(2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA)-labeled pegylated liposomal doxorubicin ({sup 188}Re-DXR-liposome) were investigated in the C26 murine colon carcinoma ascites mouse model. After intraperitoneal administration of the nanotargeted bimodality {sup 188}Re-DXR-liposome, the ascites and tumor accumulation of the radioactivity were observed, the levels of radioactivity within the ascites were maintained at relatively higher levels before 48 h and the levels of radioactivity in the tumor were maintained at steady levels after 4 h. The AUC{sub (o{yields}{infinity})} of {sup 188}Re-DXR-liposome in blood, ascites and tumor was 9.3-, 4.2- and 4.7-fold larger than that of {sup 188}Re-BMEDA, respectively. The maximum tolerated dose of intraperitoneally administrated {sup 188}Re-DXR-liposome was determined in normal BALB/c mice. The survival, tumor and ascites inhibition of mice after {sup 188}Re-DXR-liposome (22.2 MBq of {sup 188}Re, 5 mg/kg of DXR) treatment were evaluated. Consequently, radiochemotherapeutics of {sup 188}Re-DXR-liposome attained better survival time, tumor and ascites inhibition (decreased by 49% and 91% at 4 days after treatment; P<.05) in mice than radiotherapeutics of {sup 188}Re-liposome or chemotherapeutics of Lipo-Dox did. Therefore, intraperitoneal administration of novel {sup 188}Re-DXR-liposome could provide a benefit and promising strategy for delivery of passive nanotargeted bimodality radiochemotherapeutics in oncology applications.

  3. Peptide receptor radionuclide therapy with 90Y/177Lu-labelled peptides for inoperable head and neck paragangliomas (glomus tumours)

    Head and neck paragangliomas (HNPGLs) are rare tumours arising from autonomic nervous system ganglia. Although surgery offers the best chance of complete cure, there is associated morbidity due to the crucial location of these tumours. Radiotherapy arrests tumour growth and provides symptomatic improvement, but has long-term consequences. These tumours express somatostatin receptors (SSTR) and hence peptide receptor radionuclide therapy (PRRT) is now a treatment option. We assessed the molecular, morphological and clinical responses of inoperable HNPGLs to PRRT. Nine patients with inoperable HNPGL assessed between June 2006 and June 2014 were included. Four patients had a solitary lesion, four had multifocal involvement and one had distant metastases (bone and lungs). The patients were treated with PRRT using 90Y/177Lu-labelled peptides after positive confirmation of SSTR expression on 68Ga-DOTATOC PET/CT. All patients received two to four courses of PRRT. Subsequent serial imaging with 68Ga-DOTATOC PET/CT was carried out every 6 months to assess response to treatment. Clinical (symptomatic) response was also assessed. Based on molecular response (EORTC) criteria, four of the nine patients showed a partial molecular response to treatment seen as significant decreases in SUVmax, accompanied by a reduction in tumour size. Five patients showed stable disease on both molecular and morphological criteria. Six out of nine patients were symptomatic at presentation with manifestations of cranial nerve involvement, bone destruction at the primary site and metastatic bone pain. Molecular responses were correlated with symptomatic improvement in four out of these six patients; while two patients showed small reductions in tumour size and SUVmax. The three asymptomatic patients showed no new lesions or symptomatic worsening. PRRT was effective in all patients, with no disease worsening seen, either in the form of neurological symptoms or distant spread. Though these are

  4. Intratumoral injection with [188Re]rhenium sulfide suspension for treatment of transplanted human liver carcinoma in nude mice

    Hepatocellular carcinoma (HCC) is one of the most common malignancies in China. Direct intratumoral injection of non removable radioactive material has been widely studied because it could deliver high doses of radiation to target sites and minimize radiation leakage to non-target organs or tissues. Thirty nude mice bearing SMMC 7721 human liver carcinoma were used for the biodistribution study after intratumoral injection of [188Re]rhenium sulfide suspension or sodium [188Re]perrhenate solution. Another 30 tumor-bearing mice were divided into six groups, four groups of which were treated with a 0.1 ml [188Re]rhenium sulfide suspension at doses of 3.7, 7.4, 18.5, 29.6 MBq by a single intratumoral injection. For control studies, to study the tumor inhibiting ratio, the remaining two groups were injected with nonradioactive rhenium sulfide suspension and Hanks' balanced salt solution, respectively. The injections were repeated 6 days later. The retention percentages of radioactivity (%ID) in tumors injected with [188Re]rhenium sulfide suspension were 90.96 ± 6.63%, 86.09 ± 22.58% and 87.62 ± 13.97% at 1, 24 and 48 h, respectively. Tumor inhibition ratios are as high as 89% when the outer space of tumor (0.5-0.6 cm from center) received about 507.6 Gy doses. Intratumoral injection of [188Re]rhenium sulfide suspension results in high tumor retention indicating this approach has strong potential for the treatment of hepatic carcinoma

  5. Development of 188Re-HEDP as radiopharmaceutical for palliative bone pain

    Full text: The optimized condition for labeling HEDP with Re-188 was assessed by wet labeling. The mixture solution of 10 mg HEDP, 3 mg SnCl2.2H2O, 4 mg Gentisic acid and 50 ?g of NH4ReO4 was labeled with 3- 10 mCi ReO-4 at pH1 with heating temperature at 100 ?C for 15 minutes. After adjusting pH to 5-6 with 0.3 M NaOAc pH 8 and NaOH, radiochemical purity of the labeled product was checked by TLC. Labeling efficiency was high as 98.88%. The HEDP ligand was prepared in form of lyophilized kits then labeled and controlled for labeling efficiency. Labeling yield of labeled HEDP kits were more than 94% for 5 months storage. Biodistribution of 188Re-HEDP in rat measured in % injected dose/g of bone at time 2, 4 and 24 hours was 1.372%, 1.302% and 1.154%, respectively

  6. Decay of 188Re and TRS calculations for its daughter nuclide 188Os

    The γ-ray spectra of 188Re decay have been studied by using a Compton-suppressed spectrometer and a three parameters γ-γ-T list coincidence system. Experimental data analysis demonstrated that six γ-rays at 557, 810, 1463, 1867, 1936 and 2022 keV and three levels at 1443, 1936 and 2022 keV are confirmed again. Seven new γ-rays at 309.60±0.04, 826.90±0.02, 979.29±0.08, 1103.7±0.4, 1828.2±0.1, 1842.5±0.2 and 1982.5±0.2 keV have been identified, three new levels at 309.60, 1828.2 and 1982.5 keV are assigned. The β- decay branching ratio is deduced. In addition, in order to study this γ-unstable nucleus, shape calculations using the Hartree–Fock–Bogoliubov-like formalism were carried out for positive-parity states in 188Os. The TRS plots reveal that, as the spin increases up the band, the triaxiality parameter γ changes. (author)

  7. Microwave assisted facile one-pot synthesis of 188Re-complex using a tetrahydroborate exchange resin. A bifunctional chelating agent for radiopharmaceuticals

    A facile one-pot synthesis of 188Re-complex as a bifunctional chelating agent for the preparation of therapeutic radiopharmaceuticals was accomplished with good labeling yields and radiochemical purity by using a tetrahydroborate exchange resin as a reducing agent for a disulfide ligand as well as the [188Re] perrhenate ion under microwave irradiation. (author)

  8. Preparation, biodistribution, and dosimetry of 188Re-Labeled MoAb ior cea1 and its f(ab')2 fragments by avidin-biotin strategy

    The biotinylated monoclonal antibody (MoAb) ior cea1 and its F(ab')2 fragments were labeled with Re-188 by combination of avidin-biotin strategy. 188Re-MoAb, 188Re-MoAb-biotin, 188Re-F(ab')2, and 188Re-F(ab')2-biotin preparations were produced for these studies with specific activities of 1.30±0.18 GBq/mg and from instant freeze-dried kit formulations using ethane-1-hydroxy-1,1-diphosphonic acid (EHDP) as a weak competing ligand. There were no significant differences (p>0.05) between the biodistribution in mice of biotinylated and unbiotinylated 188Re-labeled immunoconjugates. When avidin was injected as a chase after injection of 188Re-MoAb-biotin or 188Re-F(ab')2-biotin, the blood radioactivity level decreased approximately 75% (cumulated activity) and the effective dose decreased almost 25% with respect to that of the radioimmunoconjugates in which the chase effect was not used. Our results suggest that 188Re-labeled biotinylated MoAb ior cea1 and its F(ab')2 fragments prepared by this method are stable complexes in vivo

  9. Survival curves study of platelet labelling with 51Cr

    Platelet kinetics and idiopathic thrombocytopenic purpura were researched in the literature. An 'in vitro' platelet labelling with 51Cr procedure in implementation has been evaluated in human beings. Functions used for fitting considered the cases whether the curve was linear or exponential as well as the presence of hematies. (author)

  10. 51Cr diffusion in Zr-Sn alloys

    The 51Cr volume diffusion in Zr-Sn alloys is measured in polycrystals with big grains by the thin-film method. The Sn content in the alloys ranges from 0.39% at to 6.66 % at. In the beta-phase the analysed temperature range is 982 deg C-1240 deg C. The Sn dehances the 51Cr diffusion in beta-Zr, the effect being small but well defined. Assuming the formation of Sn-Cr dimers, the linear dehancement coefficient b and the parameters for the variation of b with temperature were calculated. The parameters Q and Do were calculated for the more diluted alloys and, upon application of the Zener theory for Do, a negative contribution to the activation entropy is found. Three experiments at different temperatures were performed in the alpha-phase. 51Cr diffuses very fast in alpha-Zr-Sn. No definite correlation is found between the 51Cr diffusivity and the increasing Sn concentration, probably due to the anisotropy of the alfa-phase. (M.E.L.)

  11. A comparative study of preliminary dosimetry for human based on distribution data in rats with 111In, 90Y, 153Sm, and 177Lu labeled rituximab

    Radfar Edalat

    2012-01-01

    Full Text Available Radio immunotherapy is one of the most important and effective therapies for B-cell non Hoddgkin’s lymphoma treatment. Today, anti CD-20 antibodies labeled with beta emitter radionuclides are used in radio immunotherapy. Various radionuclides for labeling anti CD-20 antibodies have been studied and developed for the treatment and diagnosis of malignancies. This paper describes the preparation, bio-distribution and absorbed dose rate of 111In, 90Y, 177Lu, and 153Sm labeled anti CD-20 antibodies (rituximab in human organs, after injection to rats. The macro cyclic bifunctional chelating agent, N-succinimidyl-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA-NHS for conjugation to antibody, was used to prepare DOTA-rituximab. The conjugates were purified by molecular filtration, the average number of DOTA conjugated per mAb was calculated and total concentration was determined by spectrophotometric method. Radio-labeling was performed at 40 °C for 24 hours. After the quality control studies, the final radioactive solution was injected intravenously into rats through their tail vein. The tissue uptakes of each injection were measured. Then we calculated S values for 177Lu and 153Sm by using specific absorbed fractions and data used in the manner of radio-labeled analysis and dosimetry for humans. The absorbed dose rate of each organ was calculated in the specific time by medical internal radiation dose method with linear approximation in the activity measurements.

  12. Development of {sup 177}Lu-DTPA-SPIO conjugates for potential use as a dual contrast SPECT/MRI imaging agent

    Shanehsazzadeh, Saeed; Yousefnia, Hassan [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Gruettner, Cordula [Micromod Partikeltechnologie GmbH, Rostock (Germany); and others

    2016-08-01

    This study describes the preparation, biodistribution of {sup 177}Lu-DTPA-SPIO after intravenous injection in rats. The chelator DTPA dianhydride was conjugated to SPIO NPs using a small modification of the well-known cyclic anhydride method. Conjugation was done at a 1:2 (SPIO:ccDTPA) molar ratio. Conjugation reaction was purified with Magnetic assorting column (MACs) using high gradient magnetic field following incubation, the radio labeled conjugate was checked using RTLC method for labeling and purity checked. The RTLC showed that labeling yield was above 99% after purification and the compound have good in-vitro stabilities until 48 h post injection in the presence of human serum. The biodistribution of {sup 177}Lu-DTPA-SPIO in rats showed dramatic uptake in the reticuloendothelial system (RES) and their clearance is so fast in other organs especially in the blood. In conclusion, due to high uptakes of this radiotracer in the liver and spleen and their fast clearance from other tissues, especially in blood, it is suggested that this radiotracer would be suitable for RES studies.

  13. Individualized dosimetry in patients undergoing therapy with {sup 177}Lu-DOTA-D-Phe{sup 1}-Tyr{sup 3}-octreotate

    Sandstroem, Mattias [Uppsala University Hospital, Department of Oncology, Radiology and Clinical Immunology, Division of Medical Physics, Uppsala (Sweden); Uppsala University Hospital, Department of Hospital Physics, Uppsala (Sweden); Garske, Ulrike [Uppsala University Hospital, Department of Medical Sciences, Division of Nuclear Medicine, Uppsala (Sweden); Granberg, Dan [Uppsala University Hospital, Department of Medical Sciences, Division of Endocrine Oncology, Uppsala (Sweden); Sundin, Anders [Karolinska University Hospital, Department of Molecular Medicine and Surgery, Division of Diagnostic Radiology, Stockholm (Sweden); Lundqvist, Hans [Uppsala University, Department of Oncology, Radiology and Clinical Immunology, Rudbeck Laboratory, Uppsala (Sweden)

    2010-02-15

    In recent years, targeted radionuclide therapy with [{sup 177}Lu-DOTA{sup 0}, Tyr{sup 3}]octreotate for neuroendocrine tumours has yielded promising results. This therapy may be further improved by using individualized dosimetry allowing optimization of the absorbed dose to the tumours and the normal organs. The aim of this study was to investigate the feasibility and reliability of individualized dosimetry based on SPECT in comparison to conventional planar imaging. Attenuation-corrected SPECT data were analysed both by using organ-based volumes of interest (VOIs) to obtain the total radioactivity in the organ, and by using small VOIs to measure the tissue radioactivity concentration. During the first treatment session in 24 patients, imaging was performed 1, 24, 96 and 168 h after [{sup 177}Lu-DOTA{sup 0}, Tyr{sup 3}]octreotate infusion. Absorbed doses in non tumour-affected kidney, liver and spleen were calculated and compared for all three methods (planar imaging, SPECT organ VOIs, SPECT small VOIs). Planar and SPECT dosimetry were comparable in areas free of tumours, but due to overlap the planar dosimetry highly overestimated the absorbed dose in organs with tumours. Furthermore, SPECT dosimetry based on small VOIs proved to be more reliable than whole-organ dosimetry. We conclude that SPECT dosimetry based on small VOIs is feasible and more accurate than conventional planar dosimetry, and thus may contribute towards optimising targeted radionuclide therapy. (orig.)

  14. Formation of medical radioisotopes {sup 111}In, {sup 117m}Sn, {sup 124}Sb, and {sup 177}Lu in photonuclear reactions

    Danagulyan, A. S.; Hovhannisyan, G. H., E-mail: hov-gohar@ysu.am; Bakhshiyan, T. M. [Yerevan State University (Armenia); Avagyan, R. H.; Avetisyan, A. E.; Kerobyan, I. A.; Dallakyan, R. K. [A.I. Alikhanian National Science Laboratory (Yerevan Physics Institute) (YerPhI) (Armenia)

    2015-06-15

    The possibility of the photonuclear production of radioisotopes {sup 111}In, {sup 117m}Sn, {sup 124}Sb, and {sup 177}Lu is discussed. Reaction yields were measured by the gamma-activation method. The enriched tin isotopes {sup 112,} {sup 118}Sn and Te and HfO{sub 2} of natural isotopic composition were used as targets. The targets were irradiated at the linear electron accelerator of Alikhanian National Science Laboratory (Yerevan) at the energy of 40 MeV. The experimental results obtained in this way reveal that the yield and purity of radioisotopes {sup 111}In and {sup 117}mSn are acceptable for their production via photonuclear reactions. Reactions proceeding on targets from Te and HfO{sub 2} of natural isotopic composition and leading to the formation of {sup 124}Sb and {sup 177}Lu have small yields and are hardly appropriate for the photoproduction of these radioisotopes even in the case of enriched targets.

  15. Synthesis and evaluation of Lys{sup 1}(α, γ-Folate)Lys{sup 3}({sup 177}Lu-DOTA)-Bombesin(1-14) as a potential theranostic radiopharmaceutical for breast cancer

    Aranda L, L.; Ferro F, G.; Azorin V, E.; Ramirez, F. M.; Ocampo G, B.; Santos C, C.; Jimenez M, N. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Issac O, K. [Universidad Autonoma del Estado de Mexico, Facultad de Medicina, 50180 Toluca, Estado de Mexico (Mexico)

    2015-10-15

    Full text: Lutetium-177 labeled hetero bivalent molecules that interact with different targets on tumor cells have been proposed as a new class of theranostic radiopharmaceuticals. The aim of this work was to synthesize Lys{sup 1} (α,γ-Folate)-Lys{sup 3}({sup 177}Lu-DOTA)-Bombesin (1-14) ({sup 177}LuFolate-Bn), as well as to assess its in vitro and in vivo potential for molecular imaging and targeted radiotherapy of breast tumors expressing folate receptors (Fr) and gastrin releasing peptide receptors (GRPR). Lys{sup 1} Lys{sup 3} (DOTA)-Bombesin (1-14) was conjugated to the terminal carboxylic group of the folic acid and the product purified by size-exclusion HPLC. Chemical characterization was carried out by UV-vis, Ft-IR spectroscopies and MALDI-TOF mass spectrometry. {sup 177}Lu labeling was performed by reaction of {sup 177}LuCl{sub 3} with the Lys{sup 1} (α,γ-Folate)-Lys{sup 3} (DOTA)-Bombesin (Folate-Bn) conjugate. In vitro binding studies were carried out in T47D breast cancer cells (positive to Fr and GRPR). Biokinetic studies and micro-SPECT/CT images were obtained using athymic mice with T47D induced tumors. Spectroscopic studies and HPLC analyses indicated that the conjugate was obtained with high chemical and radiochemical purity (98 ± 1.3%). T47D-tumors were clearly visible with high contrast at 2 h after radiopharmaceutical administration. The {sup 177}Lu-absorbed dose delivered to tumors was 23.9 ± 2.1 Gy (74 MBq, intravenously administered) {sup 177}Lu-Folate-Bn demonstrated properties suitable as a theranostic radiopharmaceutical for breast tumors expressing Fr s and GRPR s. (Author)

  16. Synthesis and evaluation of Lys1(α, γ-Folate)Lys3(177Lu-DOTA)-Bombesin(1-14) as a potential theranostic radiopharmaceutical for breast cancer

    Full text: Lutetium-177 labeled hetero bivalent molecules that interact with different targets on tumor cells have been proposed as a new class of theranostic radiopharmaceuticals. The aim of this work was to synthesize Lys1 (α,γ-Folate)-Lys3(177Lu-DOTA)-Bombesin (1-14) (177LuFolate-Bn), as well as to assess its in vitro and in vivo potential for molecular imaging and targeted radiotherapy of breast tumors expressing folate receptors (Fr) and gastrin releasing peptide receptors (GRPR). Lys1 Lys3 (DOTA)-Bombesin (1-14) was conjugated to the terminal carboxylic group of the folic acid and the product purified by size-exclusion HPLC. Chemical characterization was carried out by UV-vis, Ft-IR spectroscopies and MALDI-TOF mass spectrometry. 177Lu labeling was performed by reaction of 177LuCl3 with the Lys1 (α,γ-Folate)-Lys3 (DOTA)-Bombesin (Folate-Bn) conjugate. In vitro binding studies were carried out in T47D breast cancer cells (positive to Fr and GRPR). Biokinetic studies and micro-SPECT/CT images were obtained using athymic mice with T47D induced tumors. Spectroscopic studies and HPLC analyses indicated that the conjugate was obtained with high chemical and radiochemical purity (98 ± 1.3%). T47D-tumors were clearly visible with high contrast at 2 h after radiopharmaceutical administration. The 177Lu-absorbed dose delivered to tumors was 23.9 ± 2.1 Gy (74 MBq, intravenously administered) 177Lu-Folate-Bn demonstrated properties suitable as a theranostic radiopharmaceutical for breast tumors expressing Fr s and GRPR s. (Author)

  17. Pharmacokinetics, dosimetry and comparative efficacy of 188Re-liposome and 5-FU in a CT26-luc lung-metastatic mice model.

    Chen, Liang-Cheng; Wu, Yu-Hsien; Liu, I-Hshiang; Ho, Chung-Li; Lee, Wan-Chi; Chang, Chih-Hsien; Lan, Keng-Li; Ting, Gann; Lee, Te-Wei; Shien, Jui-Hung

    2012-01-01

    The biodistribution, pharmacokinetics, dosimetry and comparative therapeutic efficacy of intravenously administrated (188)Re-N,N-bis(2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA)-labeled pegylated liposome ((188)Re-liposome) and 5-FU were investigated in a CT26-luc lung-metastatic model. After intravenous administration of (188)Re-liposome, tumor accumulation from the radioactivity was observed. Levels of radioactivity in tumors were maintained at steady levels (from 5.40 to 5.67 %ID/g) after 4 to 24 h. In pharmacokinetics, the AUC((0→∞)), MRT((0→∞)) and Cl of (188)Re-liposome in blood via intravenous route were 998 h %ID/ml, 28.7 h and 0.1 ml/h, respectively. The total excreted fractions of feces and urine were 0.61 and 0.26, respectively. Absorbed doses for (188)Re-liposome in the liver and red marrow were 0.31 and 0.08 mSv/MBq, respectively. Tumor-absorbed doses for (188)Re-liposome ranged from 48.4 to 1.73 mGy/MBq at 10 to 300 g tumor spheres. In therapeutic efficacy, the survival times of mice after (188)Re-liposome [80% maximum tolerated dose (MTD); 29.6 MBq], 5-FU (80% MTD; 144 mg/kg), liposome or normal saline treatments were evaluated. Consequently, radiotherapeutics of (188)Re-liposome attained a longer lifespan (increase of 34.9%; P=.005) in mice than in the normal saline group. The increase in lifespan of the (188)Re-liposome group was 2.5-fold greater than that of the 5-FU group. Therefore, intravenous administration of (188)Re-liposome could provide a benefit and it is a promising strategy for delivery of passive nanotargeted radiotherapeutics in oncology applications. PMID:21958858

  18. Pharmacokinetics, dosimetry and comparative efficacy of 188Re-liposome and 5-FU in a CT26-luc lung-metastatic mice model

    The biodistribution, pharmacokinetics, dosimetry and comparative therapeutic efficacy of intravenously administrated 188Re-N,N-bis(2-mercaptoethyl)-N′,N′-diethylethylenediamine (BMEDA)-labeled pegylated liposome (188Re-liposome) and 5-FU were investigated in a CT26-luc lung-metastatic model. After intravenous administration of 188Re-liposome, tumor accumulation from the radioactivity was observed. Levels of radioactivity in tumors were maintained at steady levels (from 5.40 to 5.67 %ID/g) after 4 to 24 h. In pharmacokinetics, the AUC(0→∞), MRT(0→∞) and Cl of 188Re-liposome in blood via intravenous route were 998 h %ID/ml, 28.7 h and 0.1 ml/h, respectively. The total excreted fractions of feces and urine were 0.61 and 0.26, respectively. Absorbed doses for 188Re-liposome in the liver and red marrow were 0.31 and 0.08 mSv/MBq, respectively. Tumor-absorbed doses for 188Re-liposome ranged from 48.4 to 1.73 mGy/MBq at 10 to 300 g tumor spheres. In therapeutic efficacy, the survival times of mice after 188Re-liposome [80% maximum tolerated dose (MTD); 29.6 MBq], 5-FU (80% MTD; 144 mg/kg), liposome or normal saline treatments were evaluated. Consequently, radiotherapeutics of 188Re-liposome attained a longer lifespan (increase of 34.9%; P=.005) in mice than in the normal saline group. The increase in lifespan of the 188Re-liposome group was 2.5-fold greater than that of the 5-FU group. Therefore, intravenous administration of 188Re-liposome could provide a benefit and it is a promising strategy for delivery of passive nanotargeted radiotherapeutics in oncology applications.

  19. Biodistribution of 188Re-labeled stannic sulfur colloid in rabbit orthotopic liver cancer model by intratumoral injection

    Objective: To study the biodistribution of 188Re-labeled stannic sulfur colloid in rabbit orthotopic VX2 liver cancer model by intratumoral injection and to evaluate its potential for endoradiotherapy. Methods: 188Re-labeled stannic sulfur colloid was prepared with direct labeling method. The labeling efficiency and radiochemical purity were measured. Twelve rabbits xenografted by orthotopic VX2 liver cancer were used to determine the biodistribution of 188Re-labeled stannic sulfur colloid. Under CT guidance, 37 MBq (0.1 ml) 188Re-labeled stannic sulfur colloid was injected directly into the center of the tumor. Four rabbits were sacrificed after gamma imaging at 1, 24, 48 h post injection. The organ uptake was calculated as %ID/g, the absorbed dose and T/NT ratio were calculated. One-way analysis of variance was used to analyze the data. Results: The labeling efficiency of 188Re-labeled stannic sulfur colloid was (98.23±0.25)%. The radiochemical purity was (94.23±0.54) % at 48 h. The radioactivity essentially accumulated in the tumor area and remained trapped up to 48 h. The radioactivity in other organs was at background level. The T/NT ratios were 88.22± 11.57, 32.87±9.13 and 31.65± 10.11 at 1, 24 and 48 h post injection respectively, with the corresponding tumor uptakes of (43.318±11.931) %ID/g, (39.875±9.290) %ID/g and (37.761±6.849) %ID/g, which were much higher than those in normal tissues (F=77.350, 97.577, 417.072, all P<0.01). Radiation dose to the tumor was (88.12 ± 12.21) Gy. Conclusions: 188Re-labeled stannic sulfur colloid may have a stable distribution at the site of orthotopic VX2 liver cancer after intratumoral injection. Thus it may have potential for the endoradiotherapy of liver cancer. (authors)

  20. Development of methods of labeling pentavalent DMSA with {sup 99m}Tc and {sup 188}Re; Desenvolvimento de metodos para marcacao de DMSA pentavalente com {sup 99m}Tc e {sup 188}Re

    Brambilla, Tania de Paula, email: jtoniolo@ipen.br

    2009-07-01

    Technetium-99 m is the most useful radionuclide in diagnostic imaging procedures in Nuclear Medicine, more than 80 percent of radiopharmaceuticals are {sup 99m}Tc-labeled compounds. {sup 99m}Tc-DMSA(V) has been used for imaging of soft tissue, head and neck tumors. It shows a particularly high specificity for medullary thyroid carcinoma and bone metastases in a variety of cancers. Biodistribution studies of {sup 188}Re-DMSA(V) have shown that its general pharmacokinetic properties are similar to that of {sup 99m}Tc-DMSA(V), so this agent could be used for targeted radiotherapy of these tumors. The aim of this work is the development of methods of labeling DMSA(V) with {sup 99m}Tc and {sup 188}Re. {sup 99m}Tc-DMSA(V) can be prepared by two methods. One of them is the indirect one, through the use of a commercial kit of DMSA (III), by adjusting the pH from 2.5 to {approx} 8.5 with NaHCO{sub 3}. This method was evaluated and optimized presenting high labeling yields. The other method is the direct one, through the preparation of a lyophilised kit ready for labeling with {sup 99m}Tc, being the method of interest of this work, due to the easy of its clinical use. The most adequate formulation of the kit was: 1.71 mg of DMSA, 0.53 mg of SnCl{sub 2}.2H{sub 2}O and 0.83 mg of ascorbic acid (pH 9). Labeling yields higher than 95% were achieved labeling this kit with 1 to 2 m L of {sup 99m}Tc with activities up to 4736 MBq (128 mCi). The kit was stable up to 6 months and biodistribution studies confirmed the quality of the DMSA (V) labeled with {sup 99m}Tc using this kit. The reduction potential of Re is lower than the one for Tc, so the labeling conditions of {sup 188}Re-DMSA(V) are different from the ones used for {sup 99m}Tc- DMSA(V). {sup 188}Re-DMSA(V) is prepared in acid solution, that makes it possible to use the DMSA (III) commercial kit developed for labeling with {sup 99m}Tc, prepared in pH 2.5, for labeling with {sup 188}Re. Labeling yields higher than 95% were

  1. Studies on biodistribution and imaging of 188Re labeled insulin-like growth factor-1 analogue in nude mice bearing human pancreatic carcinoma

    Objective: To evaluate the biodistribution and planar gamma camera imaging characteristics of 188Re labeled insulin-like growth factor 1 analogue (188Re-IGF-1A) in tumor-bearing mice. Methods: (1)To label IGF-1A with 188Re directly and to determine the labeling efficiency. (2)To establish nude mice model which bearing human pancreatic carcinoma cell Patu8988. (3)To scan those nude mice at 15 min, 1 h, 4 h, 24 h, 3 d and 5 d after intratumor injection with 188Re-IGF-1A into their tumors. (4)To scan those nude mice at 15 min, 1 h, 2 h, 4 h and 24 h after intratumor injection with 188ReO4- into their tumors. To calculate the tumor to normal tissue ratio (T/NT) and the percentages of injected dose per gram tissue (%ID/g) of different organs. Results: (1)The labeling efficiency of 188Re-IGF-1A was (94.07 ± 0.32)%. (2)The largest uptake of tumors was (42.38 ± 17.82)%ID/g at 4 h after injection of 188Re-IGF-1A. Then the tumor to normal tissue ratios 5ncreased and the largest tumor to muscle ratio was 6531.79 ± 4930.26 at 5 d after injection. (3) 188ReO4- was major distributed in thyroid glands, stomachs, tumors and blood in nude mice after injection at first. Then %ID/g decreased rapidly in tumors. (4) The difference of %ID/g was significant (t=5.877, t=13.287, P188Re-IGF-1A group than in 188ReO4- group. The largest ratio of tumors in the two groups was 74.10 at 24 h after injection. (5) After being injected, 188Re-IGF-1A formed clear images in tumors, 5 d later, nothing but tumors can be seen. Conclusions: 188Re-IGF-1A has good affinity with human pancreatic cancer, and the tumor to muscle ratios in nude mice is high. So 188Re-IGF-1A is expected to be used for targeting therapy of human pancreatic carcinoma. (authors)

  2. Comparison of sequential planar {sup 177}Lu-DOTA-TATE dosimetry scans with {sup 68}Ga-DOTA-TATE PET/CT images in patients with metastasized neuroendocrine tumours undergoing peptide receptor radionuclide therapy

    Sainz-Esteban, Aurora; Carril, Jose Manuel [Hospital Universitario Marques de Valdecilla, Department of Nuclear Medicine, Santander (Spain); Prasad, Vikas; Schuchardt, Christiane; Zachert, Carolin; Baum, Richard P. [Zentralklinik Bad Berka, Department of Nuclear Medicine and Centre for PET/CT, Bad Berka (Germany)

    2012-03-15

    The aim of the study was to compare sequential {sup 177}Lu-DOTA-TATE planar scans ({sup 177}Lu-DOTA-TATE) in patients with metastasized neuroendocrine tumours (NET) acquired during peptide receptor radionuclide therapy (PRRT) for dosimetry purposes with the pre-therapeutic {sup 68}Ga-DOTA-TATE positron emission tomography (PET)/CT ({sup 68}Ga-DOTA-TATE) maximum intensity projection (MIP) images obtained in the same patients concerning the sensitivity of the different methods. A total of 44 patients (59 {+-} 11 years old) with biopsy-proven NET underwent {sup 68}Ga-DOTA-TATE and {sup 177}Lu-DOTA-TATE imaging within 7.9 {+-} 7.5 days between the two examinations. {sup 177}Lu-DOTA-TATE planar images were acquired at 0.5, 2, 24, 48 and 72 h post-injection; lesions were given a score from 0 to 4 depending on the uptake of the radiopharmaceutical (0 being lowest and 4 highest). The number of tumour lesions which were identified on {sup 177}Lu-DOTA-TATE scans (in relation to the acquisition time after injection of the therapeutic dose as well as with regard to the body region) was compared to those detected on {sup 68}Ga-DOTA-TATE studies obtained before PRRT. A total of 318 lesions were detected; 280 (88%) lesions were concordant. Among the discordant lesions, 29 were {sup 68}Ga-DOTA-TATE positive and {sup 177}Lu-DOTA-TATE negative, whereas 9 were {sup 68}Ga-DOTA-TATE negative and {sup 177}Lu-DOTA-TATE positive. The sensitivity, positive predictive value and accuracy for {sup 177}Lu-DOTA-TATE as compared to {sup 68}Ga-DOTA-TATE were 91, 97 and 88%, respectively. Significantly more lesions were seen on the delayed (72 h) {sup 177}Lu-DOTA-TATE images (91%) as compared to the immediate (30 min) images (68%). The highest concordance was observed for bone metastases (97%) and the lowest for head/neck lesions (75%). Concordant lesions (n = 77; mean size 3.8 cm) were significantly larger than discordant lesions (n = 38; mean size 1.6 cm) (p < 0.05). No such significance was

  3. Uptake of the 188Re(V)-DMSA complex by cervical carcinoma cells in nude mice: pharmacokinetics and dosimetry

    The uptake of the rhenium-188 (188Re(V)-DMSA) complex of dimercaptosuccinic acid by cervical carcinoma cells in nude mice was evaluated. The pharmacokinetics and dosimetry calculations in normal rats were also evaluated. The images obtained in mice did not show significant accumulation in metabolic organs and the biodistribution studies showed that 3.52±0.76% of the injected activity per gram (n=4) was taken up by the tumor. This percentage produces a cumulated activity of 35.63±8.40 MBq h and an equivalent dose per injected activity of 260±8.91 mSv/MBq. Pharmacokinetics and dosimetry of the 188Re(V)-DMSA complex indicate that this radiopharmaceutical could be evaluated in patients with soft tissue tumors, since the risk of radiation damage to the kidney or red bone marrow could not be an obstacle for its application in therapeutic nuclear medicine

  4. Studies of gel metal-oxide composite samples as filling materials for W-188/Re-188 generator column

    Iller, E.; Polkowska-Motrenko, H.; Lada, W.; Wawszczak, D.; Sypula, M.; Doner, K.; Konior, M.; Milczarek, J.; Zoladek, J.; Ráliš, Jan

    2009-01-01

    Roč. 281, č. 1 (2009), s. 83-86. ISSN 0236-5731. [9th International Conference on Nuclear Analytical Methods in the Life Sciences. Lisbon, 07.09.2008-12.09.2008] Institutional research plan: CEZ:AV0Z10480505 Keywords : W-188/Re-188 generator * W-Zr gels * W-Zr composites * Sol-gel process Subject RIV: CH - Nuclear ; Quantum Chemistry Impact factor: 0.631, year: 2009

  5. Anisotropic diffusion of 51Cr in Zr-α monocrystals

    The volume diffusion coefficients of the fast-diffusing solute 51Cr were obtained in oriented α-Zr single-crystals, in the directions parallel and perpendicular to the c axis. The dependence of those diffusion coefficients with temperature was also measured between 7500C and 8480C. Single-crystals were grown by thermal cycling through the transformation αβ (8630C). Diffusion coefficients were measured using the 'thin film' method. In some experiments non-gaussian penetration profiles were obtained and this behaviour is analyzed in the Appendix. The diffusion of 51Cr is faster in the c axis direction, with Q sub(//) (1.59 eV) < Q perpendicular to (1.69 eV). The anisotropy factor f sub(a)=D sub(//)/D perpendicular or approx. = 3. This factor, the activation energies and frequency factores are discussed in comparison with other solutes. (Author)

  6. 188Re-labelled McAb 3H11 used as preventive for the peritoneal micro-metastasis of gastric cancer

    In advancing gastric cancer, especially when the serous is invaded, the plantation of cancer cells in peritoneal is common and it affects patients' survival time severely. Based on successfully labelled McAb (monoclonal antibody) 3H11 with 188Re, the authors investigated the effect of RIT (Radio-immuno-Therapy) with 188Re-3H11 on preventing the peritoneal micro-metastasis of gastric cancer cells in nude mice to increase the survival time. After 1 x 106 BGC-823 gastric cancer cells were injected into the peritoneal cavity of each mouse, 45BABL/C nude mice were divided into 9 groups. Each group received different doses of 188Re-3H11 or 188Re-IgG, or saline I.P.16 hours post operation. The injected volume of each mouse was 1.0 mL. The results showed that the survival time depended on the injected dose during 0 to 37 MBq. The survival time was 170 +- 25.3 d after 37 MBq 188Re-3H11 were treated. It was over 5 times more than that for the saline group and about 3 times more than that for 37 MBq 188-Re IgG group (p 188Re-3H11 I.P. is effective and safe for the prevention of intra-peritoneal injected gastric cancer cells from surviving, growing and disseminating in nude mice

  7. Prediction of the correct measured activity of {sup 186}Re and {sup 188}Re from reactor produced natural rhenium using an artificial neural network

    Leila Moghaddam, B., E-mail: lmoghaddam@aut.ac.i [Faculty of Nuclear Engineering and Physics, Amirkabir Technical University (Tehran Polytechnic), Hafez Street, Tehran (Iran, Islamic Republic of); Setayeshi, Saeed; Maragheh, Mohammad G.; Gholipour, Reza [Faculty of Nuclear Engineering and Physics, Amirkabir Technical University (Tehran Polytechnic), Hafez Street, Tehran (Iran, Islamic Republic of)

    2009-11-15

    To optimize the cost effectiveness of {sup 186}Re and {sup 188}Re production, which have recently been used as radio pharmaceuticals for therapeutic purposes, we designed an artificial neural network (ANN) to evaluate the activity of combined {sup 186}Re + {sup 188}Re. One of the production ways is the (n,gamma) reaction of natural rhenium which leads to combined {sup 186}Re + {sup 188}Re. Using the counted activity of {sup 186}Re + {sup 188}Re mixtures by a well type isotope calibrator, the precise activity of {sup 186}Re and {sup 188}Re is obtained by the ANN. A back-propagation ANN was trained using 30 activities of mixed {sup 186}Re + {sup 188}Re. The performance of the ANN was tested by Early-Stopping validation method, and the ANN was optimized with respect to its architecture. The response of the ANN shows significant precision that may be used for medical application of {sup 186}Re + {sup 188}Re mixtures.

  8. Genotoxic evaluation of [DOTA,Tyr3]octreotate labeled with 131I and 177Lu in human peripheral lymphocytes in vitro by micronucleus assay

    The radiolabeled receptor-binding peptides have being used for cancer diagnosis and therapy. The octreotate, a somatostatin analogue peptide, bound to various tumors expressing sst receptors (thyroid, pancreas, prostrate, melanoma and lymphomas). The amount and the type of receptors for somatostatin influence the tissue uptake. The [DOTA, Tyr3]octreotate has been used because of its high affinity to somatostatin subtype receptors sstr2 and sstr5. The pharmacokinetic study showed that the blood clearance is rapid and only 9% of the intravenous injected activity remains in human blood after one hour. The aim of this study was to evaluate the cytogenetic effect of radiolabeled [DOTA, Tyr3]octreotate in blood cells in vitro, using the cytokinesis-block micronucleus (MN) assay. This technique allows evaluating the mutagenic effects of both endogenous and exogenous agents at chromosome level. Blood samples of healthy donors were collected in heparinized syringes and exposed to different activities of [DOTA, Tyr3]octreotate labeled with with 131I (n=3) and 177Lu (n=3), where radioactive concentration ranged from 600 to 5600 kBq/mL, corresponding to an injected activity of 3.1 to 28.9 GBq in a reference man of 70 kg weight. 131I and 177Lu are beta- and gamma-emitters. After one-hour exposition to radiopharmaceuticals at 37 deg C, the cells were washed with culture medium for removing the non internalised octreotate and cultivated for 72 hours, according to criteria adopted by the IAEA. The results showed a positive correlation between radioactive concentrations (X) and the frequency of binucleated cells with micronuclei (Y) (P131I-DOTA, Tyr3]octreotate was Y = (1.634 ± 0.236) + (0.912 ± 0.137) 10-3 X and for [177Lu-DOTA, Tyr3]octreotate was Y = (1.715 ± 0.342) + (0.743 ± 0.135) 10-3 X. The non labeled molecule, [DOTA, Tyr3]octreotate, has no influence in the induction of cytogenetic damage. The micronucleus assay with rat pancreatic tumor cells (AR42J) that express the

  9. {sup 99m}Tc/{sup 188}Re-labelled lipid nanocapsules as promising radiotracers for imaging and therapy: formulation and biodistribution

    Ballot, Sandrine; Noiret, Nicolas; Rajerison, Holisoa [Institut de Chimie de Rennes, Ecole Nationale Superieure de Chimie de Rennes UMR CNRS 6052 ' Syntheses et Activations de Biomolecules' , Rennes-Beaulieu (France); Hindre, Francois; Denizot, Benoit; Benoit, Jean-Pierre [Ingenierie de la Vectorisation Particulaire' , Inserm U 646, Angers (France); Garin, Etienne [Centre Eugene Marquis, Service de Medecine Nucleaire, Rennes (France)

    2006-05-15

    This study focusses on a promising carrier system for imaging and therapeutic purposes using lipid nanocapsules. To assess their potential for clinical use, we labelled nanocapsules with {sup 99m}Tc and {sup 188}Re and analysed some kinetic biodistribution parameters after intravenous injection in rats. Lipophilic complexes [{sup 99m}Tc/{sup 188}Re(S{sub 3}CPh){sub 2}(S{sub 2}CPh)] ({sup 99m}Tc/{sup 188}Re-SSS) were encapsulated within the nanoparticles during their manufacture with quantitative yield and satisfactory radiochemical purity. Rats were injected intravenously with 3.7 MBq {sup 99m}Tc/{sup 188}Re-labelled nanocapsules and sacrificed at 5, 15 and 30 min and 1, 2, 4, 8, 12, 16, 20 and 24 h. Dynamic scintigraphic acquisitions showed predominant hepatic uptake, and ex vivo counting indicated a long circulation time of labelled nanocapsules, with a half-life of 21{+-}1 min for {sup 99m}Tc and 22{+-}2 min for {sup 188}Re. Very weak urinary elimination was observed, indicating good stability of {sup 99m}Tc and {sup 188}Re labelling. {sup 99m}Tc/{sup 188}Re-SSS nanocapsules can be obtained with high yield and satisfactory radiochemical purity. The biodistributions of {sup 99m}Tc/{sup 188}Re-labelled nanocapsules are close to those of classical PEG-coated particles and show good stability of {sup 188}Re/{sup 99m}Tc-SSS labelling. (orig.)

  10. {sup 177}Lu- labeled MOv18 as compared to {sup 131}I- or {sup 90}Y-labeled MOv18 has the better therapeutic effect in eradication of alpha folate receptor-expressing tumor xenografts

    Zacchetti, Alberto [Unit of Molecular Therapies, Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan 20133 (Italy); Coliva, Angela [Department of Imaging and Nuclear Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan 20133 (Italy); Luison, Elena [Unit of Molecular Therapies, Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan 20133 (Italy); Seregni, Ettore; Bombardieri, Emilio [Department of Imaging and Nuclear Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan 20133 (Italy); Giussani, Augusto [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, Neuherberg (Germany); Figini, Mariangela [Unit of Molecular Therapies, Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan 20133 (Italy); Canevari, Silvana [Unit of Molecular Therapies, Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan 20133 (Italy)], E-mail: silvana.canevari@istitutotumori.mi.it

    2009-10-15

    Introduction: The mouse monoclonal antibody MOv18, directed against the {alpha}-isoform of folate receptor (FR), was investigated to identify the optimal radioconjugate for radioimmunotherapy of minimal residual disease in ovarian cancer. Methods: Pharmacokinetics, biodistribution, long-term therapeutic efficacy and toxicity of MOv18, labeled with the beta-emitters {sup 131}I, {sup 90}Y and {sup 177}Lu, were compared in a xenografted mouse model, composed by two cell lines, A431FR and A431MK, differing only for FR expression. Results: A shorter blood clearance and a higher tumor uptake were observed for {sup 90}Y- and {sup 177}Lu- compared to {sup 131}I-MOv18, and a shorter blood pharmacokinetics was recorded in A431FR-bearing animals. At equitoxic maximum tolerable doses, the general irradiation by {sup 131}I- and {sup 90}Y-MOv18 gives rise to strong targeted effects on A431FR and nontargeted effects on A431MK tumors, while {sup 177}Lu-MOv18 was able to eradicate small size tumor masses expressing the antigen of interest exerting only mild non-targeted effects. Conclusion: {sup 177}Lu-MOv18 at the maximal tolerated dose is the immunoradioconjugate with the best therapeutic window in experimental conditions of small tumor volume.

  11. 177Lu- labeled MOv18 as compared to 131I- or 90Y-labeled MOv18 has the better therapeutic effect in eradication of alpha folate receptor-expressing tumor xenografts

    Introduction: The mouse monoclonal antibody MOv18, directed against the α-isoform of folate receptor (FR), was investigated to identify the optimal radioconjugate for radioimmunotherapy of minimal residual disease in ovarian cancer. Methods: Pharmacokinetics, biodistribution, long-term therapeutic efficacy and toxicity of MOv18, labeled with the beta-emitters 131I, 90Y and 177Lu, were compared in a xenografted mouse model, composed by two cell lines, A431FR and A431MK, differing only for FR expression. Results: A shorter blood clearance and a higher tumor uptake were observed for 90Y- and 177Lu- compared to 131I-MOv18, and a shorter blood pharmacokinetics was recorded in A431FR-bearing animals. At equitoxic maximum tolerable doses, the general irradiation by 131I- and 90Y-MOv18 gives rise to strong targeted effects on A431FR and nontargeted effects on A431MK tumors, while 177Lu-MOv18 was able to eradicate small size tumor masses expressing the antigen of interest exerting only mild non-targeted effects. Conclusion: 177Lu-MOv18 at the maximal tolerated dose is the immunoradioconjugate with the best therapeutic window in experimental conditions of small tumor volume.

  12. Enhancement of somatostatin-receptor-targeted 177Lu-[DOTAdeg. C, -Tyr3]-octreotide therapy by gemcitabine pretreatment-mediated receptor uptake, up-regulation and cell cycle modulation

    Introduction: Clinical studies of patients treated with somatostatin-receptor (sstr)-targeted [DOTAdeg. C, -Tyr3]-octreotide (DOTATOC) labeled with 177Lu and 9deg. C, Y have shown overall response rates in the range of 9-33%. This study evaluates the potential for combination therapy with gemcitabine in an effort to improve clinical outcomes. Methods: Human pancreatic adenocarcinoma Capan-2, rat pancreatic cancer AR42J and human small cell lung cancer NCI-H69 cells were each treated with 1 μg/ml gemcitabine for 4 days followed by replacement of the medium alone for four additional days. Cell cycle and direct receptor-uptake studies were performed with 177Lu-DOTATOC after the total 8-day treatment as described. Cell viability and apoptosis experiments were performed to study the effects of gemcitabine pretreatment and 177Lu-DOTATOC radionuclide therapy. Parallel control studies were performed with receptor-non-targeted 177Lu-DOTA and DOTATOC. Results: Cells treated with gemcitabine for 4 days showed a down-regulation of sstr expression as determined by 177Lu-DOTATOC uptake. However, after 4 days of additional growth in absence of gemcitabine, the uptake of 177Lu-DOTATOC was 1.5-3 times greater than that of the untreated control cells. In gemcitabine-pretreated Capan-2 cells, 84% of the cell population was in the G2M phase of the cell cycle. Due to sstr up-regulation and cell cycle modulations, synergistic effects of gemcitabine pretreatment were observed in cell viability and apoptosis assays. 177Lu-DOTATOC resulted in two to three times greater apoptosis in gemcitabine-pretreated Capan-2 cells compared to the untreated cells. Conclusion: Gemcitabine pretreatment up-regulates sstr expression and acts as a radiosensitizer through cell cycle modulation. The rational combination of gemcitabine and sstr-targeted radiopharmaceuticals represents a promising chemoradiation therapeutic tool with great potential to improve clinical outcomes and, thus, merits further study

  13. Induction of Anti-Tumor Immune Responses by Peptide Receptor Radionuclide Therapy with 177Lu-DOTATATE in a Murine Model of a Human Neuroendocrine Tumor

    Michael Bzorek

    2013-10-01

    Full Text Available Peptide receptor radionuclide therapy (PRRT is a relatively new mode of internally targeted radiotherapy currently in clinical trials. In PRRT, ionizing radioisotopes conjugated to somatostatin analogues are targeted to neuroendocrine tumors (NETs via somatostatin receptors. Despite promising clinical results, very little is known about the mechanism of tumor control. By using NCI-H727 cells in an in vivo murine xenograft model of human NETs, we showed that 177Lu-DOTATATE PRRT led to increased infiltration of CD86+ antigen presenting cells into tumor tissue. We also found that following treatment with PRRT, there was significantly increased tumor infiltration by CD49b+/FasL+ NK cells potentially capable of tumor killing. Further investigation into the immunomodulatory effects of PRRT will be essential in improving treatment efficacy.

  14. Preparation and quality control of 177Lu-DOTA-Rituximab for radioimmunotherapy of relapsed and refractory B-cell NHL patients

    Full text of publication follows. Background: the prerequisite of radioimmunotherapy is stable binding of a radionuclide to monoclonal antibodies, which are specific to the tumor-associated antigen. Most B-cell lymphomas express CD20 antigen on the surface of the tumor cells, making it a suitable target for therapeutic radioactive monoclonal antibodies. In the present study, the immuno-conjugate of Rituximab and macrocyclic chelator, p-SCN-Bz-DOTA, was prepared and radiolabelled with Lutetium-177 followed by quality control procedures. Methods: Rituximab was desalted with sodium bi-carbonate (0.1 M, pH 9.0) and incubated with DOTA-SCN (1:50). The effectiveness of the conjugation was evaluated by determining the number of chelators per antibody molecule. This conjugate was radiolabelled with Lutetium-177 and purified using PD10 column. The quality control parameters like pH, clarity, radiochemical purity, in-vitro stability and pyrogenicity were studied. Immunoreactivity of 177Lu-DOTA-Rituximab was assessed using RAMOS cells. The radio-immuno-conjugate (RIC) after stringent quality assurance was injected in three patients and the biodistribution profile was analysed. Results: an average of 4.02 ± 1.04 p-SCN-Bz-DOTA molecules could be randomly conjugated to a single Rituximab antibody. The radiochemical purity of the labelled antibody was >95 % with preserved affinity for CD20 antigen. The final preparation was stable up to ∼120 hours when tested under different conditions. Bacterial endotoxin level in the sample was less than the permissible levels(<0.2 EU/ml). A favourable biodistribution profile was observed with liver showing the maximum uptake of the RIC. Conclusion: a favorable radiochemical purity, stability and biodistribution of the radiolabelled immuno-conjugate indicated that 177Lu-DOTA-antiCD20 antibody-Rituximab might be a promising therapeutic agent for the treatment of relapsed and refractory Non Hodgkin's Lymphoma. (authors)

  15. Radiochemical investigations of 177Lu-DOTA-8-Aoc-BBN[7-14]NH2: an in vitro/in vivo assessment of the targeting ability of this new radiopharmaceutical for PC-3 human prostate cancer cells

    Bombesin (BBN), a 14 amino acid peptide, is an analogue of human gastrin releasing peptide (GRP) that binds to GRP receptors (GRPr) with high affinity and specificity. The GRPr is over expressed on a variety of human cancer cells including prostate, breast, lung, and pancreatic cancers. The specific aim of this study was to identify a BBN analogue that can be radiolabeled with 177Lu and maintains high specificity for GRPr positive prostate cancer tumors in vivo. A preselected synthetic sequence via solid phase peptide synthesis (SPPS) was designed to produce a DOTA-BBN (DOTA 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) conjugate with the following general structure: DOTA-X-Q-W-A-V-G-H-L-M-(NH2), where the spacer group, X = ω-NH2(CH2)7COOH (8-Aoc). The BBN-construct was purified by reversed phase-HPLC (RP-HPLC). Electrospray Mass Spectrometry (ES-MS) was used to characterize both metallated and non-metallated BBN-conjugates. The new DOTA-conjugate was metallated with 177Lu(III)Cl3 or non-radioactive Lu(III)Cl3. The 177Lu(III)- and non-radiolabeled Lu(III)-conjugates exhibit the same retention times under identical RP-HPLC conditions. The 177Lu-DOTA-8-Aoc-BBN[7-14]NH2 conjugate was found to exhibit optimal pharmacokinetic properties in CF-1 normal mice. In vitro and in vivo models demonstrated the ability of the 177Lu-DOTA-8-Aoc-BBN[7-14]NH2 conjugate to specifically target GRP receptors expressed on PC-3 human prostate cancer cells

  16. Dosimetric evaluation of 153Sm-EDTMP, 177Lu-EDTMP and 166Ho-EDTMP for systemic radiation therapy: Influence of type and energy of radiation and half-life of radionuclides

    In radiopharmaceutical therapy, delivered doses to critical organs must be below a certain threshold therefore internal radiation dosimetry of radiopharmaceuticals is essential. Advantages and disadvantages of radionuclides with different characteristics were evaluated for selection of appropriate radionuclide. The Monte Carlo MCNPX simulation program was used to obtain radial dose and cumulative dose of 153Sm, 177Lu and 166Ho used in radiotherapy of bone metastases. A cylindrical geometry with constant density materials was supposed for simulation of femur bone. The radius of bone marrow, bone, and surrounding soft tissue was considered 0.6 cm, 1.3 cm and 4 cm, respectively. It was assumed that the radionuclides were uniformly distributed throughout the tumor. “continuous energy spectrum” of beta particle was used instead of mean beta energy. Our simulations show that absorbed dose in target organ (bone) is greater than other organs and 166Ho gives a higher dose to the critical organ of bone marrow than either 153Sm or 177Lu. Absorbed dose versus time demonstrate faster dose delivery for the short half-life radionuclides (153Sm and 166Ho). These results are in good agreement with clinical observations which show a pain relief within 1 week after intravenous administration of 153Sm-EDTMP, whereas it occurs within 2 week in the case of 177Lu-EDTMP. According to the results, combination of different radionuclides with different characteristics such as 153Sm-EDTMP and 177Lu-EDTMP could be more advantageous to patients with painful bone metastasis. - Highlights: • The radial dose and cumulative dose of 153Sm, 177Lu and 166Ho are calculated. • The effect of half-life of the radionuclide on the suitable activity for injection is studied. • Dose delivery is fast for the short half-life radionuclides (153Sm and 166Ho). • The results are in good accordance with clinical observations. • The combination of different radionuclides with different characteristics

  17. Study on radiolabeling of 1, 2, 3-triazole analogs with fac-[188Re(CO)3(H2O)3]+ via click chemistry

    Click chemistry was used to study on radiolabeling of 1, 2, 3-triazole analogs with. fac-[188Re(CO)3(H2O)3]+. CuSO4/L-sodium ascorbate was chosen as the catalyst system, three terminal alkynes were conjugated with two different azides respectively, and then the new prepared fac-[188Re(CO)3(H2O)3]+ was coordinated to the six triazoles. The results showed that the radiochemical yields (RCY) of the conjugation of fac-[188Re(CO)3]+ with six triazoles were over 90%, and the triazoles showed high stability in phosphate-buffered saline and new-born calf serum. The preliminary biological evaluation results showed that the new 188Re-labeling method via click chemistry could have general application in labeling bioactive molecules in high radiochemical yield and high specific activity for further SPECT research. (authors)

  18. Evaluation of 188Re-labeled PEGylated nanoliposome as a radionuclide therapeutic agent in an orthotopic glioma-bearing rat model

    Huang FYJ

    2015-01-01

    Full Text Available Feng-Yun J Huang,1 Te-Wei Lee,2 Chih-Hsien Chang,2 Liang-Cheng Chen,2 Wei-Hsin Hsu,2 Chien-Wen Chang,1 Jem-Mau Lo1 1Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan; 2Institute of Nuclear Energy Research, Longtan, Taiwan Purpose: In this study, the 188Re-labeled PEGylated nanoliposome (188Re-liposome was prepared and evaluated as a therapeutic agent for glioma.Materials and methods: The reporter cell line, F98luc was prepared via Lentivector expression kit system and used to set up the orthotopic glioma-bearing rat model for non-invasive bioluminescent imaging. The maximum tolerated dose applicable in Fischer344 rats was explored via body weight monitoring of the rats after single intravenous injection of 188Re-liposome with varying dosages before the treatment study. The OLINDA/EXM 1.1 software was utilized for estimating the radiation dosimetry. To assess the therapeutic efficacy, tumor-bearing rats were intravenously administered 188Re-liposome or normal saline followed by monitoring of the tumor growth and animal survival time. In addition, the histopathological examinations of tumors were conducted on the 188Re-liposome-treated rats.Results: By using bioluminescent imaging, the well-established reporter cell line (F98luc showed a high relationship between cell number and its bioluminescent intensity (R2=0.99 in vitro; furthermore, it could also provide clear tumor imaging for monitoring tumor growth in vivo. The maximum tolerated dose of 188Re-liposome in Fischer344 rats was estimated to be 333 MBq. According to the dosimetry results, higher equivalent doses were observed in spleen and kidneys while very less were in normal brain, red marrow, and thyroid. For therapeutic efficacy study, the progression of tumor growth in terms of tumor volume and/or tumor weight was significantly slower for the 188Re-liposome-treated group than the control group (P<0.05. As a result, the

  19. Radiosynthesis and evaluation of 188Re-c(RGDyK)-His as a novel radiotherapeutic agent for integrin αvβ3 targeting tumour

    The successes of noninvasive methods to visualize and quantify integrin αvβ3 expression in vivo have paved the way for radiolabeling anti-integrin therapy in clinic. Arginine-glycine-aspartice (RGD) peptide and related derivatives labeled with radionuclides for radio-therapy, which specifically targeting integrin αvβ3-positive tumors, could be used to treat these tumors. We have labeled c(RGDyK)-His, a RGD derivative, with 188Re and the radio-therapy efficiency has been evaluated in model nude mice. c(RGDyK)-His was labeled with 188Re by chelating with [188Re(CO)3(H2O)3]+ under a slightly basic condition. The in vitro specific binding affinity to U87 MG cell lines and the biodistribution of 188Re-c(RGDyK)-His in the animal tumor models was measured. The inhibitory effects of 188Re-c(RGDyK)-His were observed more than 1 month, and evaluated by microPET/CT imaging with 18F-FDG. Results of in vivo, cell uptake demonstrated 188Re-c(RGDyK)-His had a high specific binding affinity to receptor integrin αvβ3. In biodistribution experiment, 188Re-c(RGDyK)-His was accumulated in the tumor and cleared fast from the normal tissues. In radiotherapy study, tumor growth inhibition was significantly higher in the treatment groups than in the control groups. These studies showed that 188Re-c(RGDyK)-His could be effectively used for integrin αvβ3 targeting therapy. This may offer a potential therapeutic strategy for the treatment of integrin-positive tumors in clinic. (author)

  20. Assessment of canine intestinal permeability, using 51Cr-labeled ethylenediaminetetraacetate

    The 51Cr-labeled EDTA was validated as a suitable permeability probe in dogs for measurement of passive, unmediated diffusion across intestinal mucosa via intercellular pathways. The 51Cr-labeled EDTA was stable in aqueous solution and did not bind to biologic tissue and fluids. After incubation of 51Cr-labeled EDTA in isolated jejunal loops, analytic subcellular fractionation of jejunal mucosa on reorientating sucrose-density gradients was performed, and no association of 51Cr-labeled EDTA with particulate intracellular organelles was detected. Intravenously administered 51Cr-labeled EDTA was rapidly and completely excreted in urine. Intestinal permeability to 51Cr-labeled EDTA after oral administration was assessed in healthy dogs. The percentage of the administered dose of 51Cr-labeled EDTA excreted in the urine in 24 hours ranged from 2.3 to 17.6% (median, 13%)

  1. Erythrokinetics examination using 59Fe and 51Cr isotopes

    The results are discussed of 55 case studies of various hematological diseases in which 59Fe was used as a tracer in studying iron kinetics, simultaneously with 51Cr as a tracer in studying erythrocyte survival and the localization of erythrocyte destruction. The values of iron metabolism are graphically presented, while erythropoiesis data is tabulated. The method was especially beneficial in conditions that could not easily be diagnosed using laboratory techniques. They included osteomyelofibrosis, polycythemia vera, aplastic anemia, and the myelodysplastic syndrome. The method allows quantitative assessment of erythropoiesis, thus facilitating differential diagnosis in clinical practice. (L.O.). 3 figs., 1 tab., 22 refs

  2. 51Cr release and oxidative stress in the lens

    Examination of the opaque areas of human cortical cataracts has shown that a large portion of the opacity could be attributed to the globules found there. We tested models involving globule formation as a result of oxidative damage to rat lens cells in culture and whole chick embryo lenses. When cell monolayers from a lens cell line were exposed to oxidizing conditions they developed globules on the cell surface. The cells were protected from damage by the addition of glutathione and vitamin C. Thirteen-day chick embryo lenses were also incubated in oxidizing conditions and the amount of cellular damage was assessed using a chromium-51 release assay we have developed. After 24 hr the percent 51Cr in the medium increased by an average of 20% as a result of 10 mM hydrogen peroxide treatment. The addition of the 10 mM vitamin C to the hydrogen peroxide significantly reduced the 51Cr leakage to the control level. Light microscopy of sections of the lens showed a breakdown of the equatorial fibre arrangement in the presence of H2O2, while addition of vitamin C restored the fibre organization to almost normal. The findings suggest that oxidative stress is an important step in cataractogenesis and point towards the use of water soluble antioxidants as protective agents

  3. Therapeutic efficacy and microSPECT/CT imaging of {sup 188}Re-DXR-liposome in a C26 murine colon carcinoma solid tumor model

    Chang, Y.-J.; Chang, C.-H.; Yu, C.-Y.; Chang, T.-J.; Chen, L.-C. [Institute of Nuclear Energy Research, Taoyuan, Taiwan (China); Chen, M.-H. [National Health Research Institutes, Miaoli, Taiwan (China); Lee, T.-W. [Institute of Nuclear Energy Research, Taoyuan, Taiwan (China); Ting Gann [National Health Research Institutes, Miaoli, Taiwan (China)], E-mail: gann.ting@msa.hinet.net

    2010-01-15

    Nanocarriers can selectively target cancer sites and carry payloads, thereby improving diagnostic and therapeutic effectiveness and reducing toxicity. The objective of this study was to investigate the therapeutic efficacy of a new co-delivery radiochemotherapeutics of {sup 188}Re-N,N-bis (2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA)-labeled pegylated liposomal doxorubicin (DXR) ({sup 188}Re-DXR-liposome) in a C26 murine colon carcinoma solid tumor model. To evaluate the targeting and localization of {sup 188}Re-DXR-liposome in C26 murine tumor-bearing mice, biodistribution, microSPECT/CT imaging and pharmacokinetic studies were performed. The antitumor effect of {sup 188}Re-DXR-liposome was assessed by tumor growth inhibition, survival ratio and histopathological hematoxylin-eosin staining. The tumor target and localization of the nanoliposome delivery radiochemotherapeutics of {sup 188}Re-DXR-liposome were demonstrated in the biodistribution, pharmacokinetics and in vivo nuclear imaging studies. In the study on therapeutic efficacy, the tumor-bearing mice treated with bimodality radiochemotherapeutics of {sup 188}Re-DXR-liposome showed better mean tumor growth inhibition rate (MGI) and longer median survival time (MGI=0.048; 74 days) than those treated with radiotherapeutics of {sup 188}Re-liposome (MGI=0.134; 60 days) and chemotherapeutics of Lipo-Dox (MGI=0.413; 38 days). The synergistic tumor regression effect was observed with the combination index (CI) exceeding 1 (CI=1.145) for co-delivery radiochemotherapeutics of {sup 188}Re-DXR-liposome. Two (25%) of the mice treated with radiochemotherapeutics were completely cured after 120 days. The therapeutic efficacy of radiotherapeutics of {sup 188}Re-liposome and the synergistic effect of the combination radiochemotherapeutics of {sup 188}Re-DXR-liposome have been demonstrated in a C26 murine solid tumor animal model, which pointed to the potential benefit and promise of the co-delivery of

  4. Monte Carlo microdosimetry of {sup 188}Re- and {sup 131}I-labelled anti-CD20

    Torres-GarcIa, E [Coordinacion de Posgrado, Facultad de Medicina, Universidad Autonoma del Estado de Mexico, Paseo Tollocan S/N, Toluca, Estado de Mexico 50180 (Mexico); Garnica-Garza, H M [Coordinacion de Posgrado, Facultad de Medicina, Universidad Autonoma del Estado de Mexico, Paseo Tollocan S/N, Toluca, Estado de Mexico 50180 (Mexico); Ferro-Flores, G [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca, Ocoyoacac, Estado de Mexico 52750 (Mexico)

    2006-10-07

    The radiolabelled monoclonal antibody anti-CD20 has the property of binding to the CD20 antigen expressed on the cell surface of B-lymphocytes, thus making it a useful tool in the treatment of non-Hodgkin's lymphoma. In this work, the event-by-event Monte Carlo code NOREC is used to calculate the single-event distribution function f{sub 1}(z) in the cell nucleus using the beta spectra of the {sup 188}Re and {sup 131}I radionuclides. The simulated geometry consists of two concentric spheres representing the nucleus and the cell surface embedded in a semi-infinite water medium. An isotropic point source was placed on the cell surface to simulate the binding of the anti-CD20 labelled with either {sup 188}Re or {sup 131}I. The simulations were carried out for two combinations of cell surface and nucleus radii. A method was devised that allows one to calculate the contribution of betas of energy greater than 1 MeV, which cannot be simulated by the NOREC code, to the single-event distribution function. It is shown that disregarding this contribution leads to an overestimation of the frequency-mean specific energy of the order of 9-12%. In general, the antibody radiolabelled with {sup 131}I produces single-event distribution functions that yield higher frequency-mean specific energies. (note)

  5. A Freeze-Dried Kit for the Preparation of (188)Re-HEDP for Bone Pain Palliation: Preparation and Preliminary Clinical Evaluation.

    Mallia, Madhava B; Shinto, Ajit Sugunan; Kameswaran, Mythili; Kamaleshwaran, Koramadai Karuppusamy; Kalarikal, Radhakrishnan; Aswathy, K K; Banerjee, Sharmila

    2016-05-01

    (188)Re-HEDP is an established radiopharmaceutical used for pain palliation in patients with osseous metastasis. Considering commercial availability of (188)W/(188)Re generator, the accessibility to a lyophilized kit would make preparation of this radiopharmaceutical feasible at the hospital radiopharmacy having access to a generator. A protocol for the preparation of a single-vial lyophilized hydroxyethane 1,1-diphosphonic acid (HEDP) kit was developed and its consistency was checked by preparing six batches. Each sterile lyophilized kit prepared as per the protocol contained 9 mg of HEDP, 3 mg of gentisic acid, and 4 mg of SnCl2.2H2O. Randomly selected kits from all six batches were subjected to thorough quality control tests that were passed by all batches. (188)Re-HEDP could be prepared by addition of 1 mL of freshly eluted Na(188)ReO4 (up to 3700 MBq) containing 1 μmol of carrier ReO4(-) (perrhenate) and heating at 100°C for 15 minutes. (188)Re-HEDP with >95% radiochemical purity could be consistently prepared using the lyophilized kits. Sterile (188)Re-HEDP prepared using the lyophilized kit was evaluated in patients with osseous metastasis. Post-therapy images of the patient were compared with (99m)Tc-MDP bone scan and found to be satisfactory. The bone-to-background as well as tumor-to-normal bone uptake ratio was found to be significant. All patients who received therapy reported significant pain relief within a week to 10 days post-administration of (188)Re-HEDP. PMID:27183437

  6. An experimental study on the treatment of nude mice with liver carcinoma by intratumoral injection with 188Re rhenium sulfide suspension

    Objective: To prepare a [188Re] rhenium sulfide suspension and to evaluate its therapeutic effects on liver carcinoma by intratumoral injection. Methods: 30 nude mice bearing SMMC-7721 human liver carcinoma were used for the biodistribution study after intratumoral injection of [188Re] rhenium sulfide suspension or sodium [188Re] perrhenate solution. Another 30 tumor-bearing nude mice were divided into six groups, four groups of them were treated with a 0.1 mL [188Re] rhenium sulfide suspension at doses of 3.7, 7.4, 18.5, 29.6 MBq by a single intratumoral injection. For control studies, the remaining two groups were injected with nonradioactive rhenium sulfide suspension and Hanks' balanced salt solution, respectively. Every injection was repeated 6 days later. Results: The retention percentages of radioactivity (% ID) in tumors injected with [188Re] rhenium sulfide suspension were (90.96 +- 6.63)%, (86.09 +- 22.58)% and (87.62 +- 13.97)% at 1, 24 and 48 h, respectively, which were much higher than retention in normal organs evaluated. In the case of sodium 188Re-perrhenate solution, the % ID values were only (1.66 +- 0.35)%, (0.02 +- 0.01)% and (0.01 +- 0.01)%, respectively. Tumor inhibition ratios were as high as 89% when the peripheral portion of tumor (0.5 - 0.6 cm from center) absorbed an activity share of about 507.6 Gy . Conclusion: Intratumoral injection of [188Re] rhenium sulfide suspension results in significant tumor restraint and it is indicated that this is a highly potential approach to the treatment of hepatic carcinoma

  7. {sup 188}Re-HEDP combined with capecitabine in hormone-refractory prostate cancer patients with bone metastases: a phase I safety and toxicity study

    Lam, Marnix G.E.H. [University Medical Center Utrecht, Department of Nuclear Medicine, Utrecht (Netherlands); University Medical Center Utrecht, Department of Radiology and Nuclear Medicine, P.O. Box 85500, Utrecht (Netherlands); Bosma, Tjitske B.; Rijk, Peter P. van [University Medical Center Utrecht, Department of Nuclear Medicine, Utrecht (Netherlands); Zonnenberg, Bernard A. [UMC Utrecht, Department of Internal Medicine, Utrecht (Netherlands)

    2009-09-15

    {sup 188}Re-HEDP is indicated for the treatment of pain in patients with painful osteoblastic bone metastases, including hormone-refractory prostate cancer patients. Efficacy may be improved by adding chemotherapy to the treatment regimen as a radiation sensitizer. The combination of {sup 188}Re-HEDP and capecitabine (Xeloda registered) was tested in a clinical phase I study. Patients with hormone-refractory prostate cancer were treated with capecitabine for 14 days (oral twice daily in a dose escalation regimen with steps of 1/3 of 2,500 mg/m{sup 2} per day in cohorts of three to six patients, depending on toxicity). Two days later patients were treated with 37 MBq/kg {sup 188}Re-HEDP as an intravenous injection. Six hours after treatment post-therapy scintigraphy was performed. Urine was collected for 8 h post-injection. Follow-up was at least 8 weeks. The primary end-point was to establish the maximum tolerable dose (MTD) of capecitabine when combined with {sup 188}Re-HEDP. Secondary end-points included the effect of capecitabine on the biodistribution and pharmacokinetics of {sup 188}Re-HEDP. Three patients were treated in the first and second cohorts, each without unacceptable toxicity. One of six patients in the highest cohort experienced unacceptable toxicity (grade 4 thrombopaenia). The MTD proved to be the maximum dose of 2,500 mg/m{sup 2} per day capecitabine. No unexpected toxicity occurred. Capecitabine had no effect on uptake or excretion of {sup 188}Re-HEDP. Capecitabine may be safely used in combination with {sup 188}Re-HEDP in a dose of 2,500 mg/m{sup 2} per day and 37 MBq/kg, respectively. Efficacy will be further studied in a phase II study using these dosages. (orig.)

  8. Specific efficacy of peptide receptor radionuclide therapy with {sup 177}Lu-octreotate in advanced neuroendocrine tumours of the small intestine

    Sabet, Amir; Dautzenberg, Kristina; Haslerud, Torjan; Aouf, Anas; Sabet, Amin; Biersack, Hans-Juergen [University Hospital, Department of Nuclear Medicine, Bonn (Germany); Simon, Birgit [University Hospital, Department of Radiology, Bonn (Germany); Mayer, Karin [University Hospital, Department of Internal Medicine and Oncology, Bonn (Germany); Ezziddin, Samer [University Hospital, Department of Nuclear Medicine, Bonn (Germany); Saarland University, Department of Nuclear Medicine, Homburg (Germany)

    2015-07-15

    Increasing evidence supports the value of peptide receptor radionuclide therapy (PRRT) in patients with metastatic neuroendocrine tumours (NET), but there are limited data on its specific efficacy in NET of small intestinal (midgut) origin. This study aims to define the benefit of PRRT with {sup 177}Lu-octreotate for this circumscribed entity derived by a uniformly treated patient cohort. A total of 61 consecutive patients with unresectable, advanced small intestinal NET G1-2 stage IV treated with {sup 177}Lu-octreotate (4 intended cycles at 3-month intervals, mean activity per cycle 7.9 GBq) were analysed. Sufficient tumour uptake on baseline receptor imaging and either documented tumour progression (n = 46) or uncontrolled symptoms (n = 15) were prerequisites for treatment. Response was evaluated according to modified Southwest Oncology Group (SWOG) criteria and additionally with Response Criteria in Solid Tumors (RECIST) 1.1. Assessment of survival was performed using Kaplan-Meier curves and Cox proportional hazards model for uni- and multivariate analyses. Toxicity was assessed according to standardized follow-up laboratory work-up including blood counts, liver and renal function, supplemented with serial {sup 99m}Tc-diethylenetriaminepentaacetic acid (DTPA) clearance measurements. The median follow-up period was 62 months. Reversible haematotoxicity (≥ grade 3) occurred in five patients (8.2 %). No significant nephrotoxicity (≥ grade 3) was observed. Treatment response according to modified SWOG criteria consisted of partial response in 8 (13.1 %), minor response in 19 (31.1 %), stable disease in 29 (47.5 %) and progressive disease in 5 (8.2 %) patients. The disease control rate was 91.8 %. Median progression-free survival (PFS) and overall survival (OS) was 33 [95 % confidence interval (CI) 25-41] and 61 months (95 % CI NA), respectively. Objective response was associated with longer survival (p = 0.005). Independent predictors of shorter PFS were

  9. Bone marrow dosimetry in peptide receptor radionuclide therapy with [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate

    Forrer, Flavio; Krenning, Eric P.; Kooij, Peter P.; Bernard, Bert F.; Bakker, Willem H.; Teunissen, Jaap J.M.; Jong, Marion de; Kwekkeboom, Dik J. [Erasmus MC Rotterdam, Department of Nuclear Medicine, Rotterdam (Netherlands); Konijnenberg, Mark [Mallinckrodt Medical BV, Research and Development, Petten (Netherlands); Lom, Kirsten van [Erasmus MC Rotterdam, Department of Haematology, Rotterdam (Netherlands); Herder, Wouter W. de [Erasmus MC Rotterdam, Department of Internal Medicine, Rotterdam (Netherlands)

    2009-07-15

    Adequate dosimetry is mandatory for effective and safe peptide receptor radionuclide therapy (PRRT). Besides the kidneys, the bone marrow is a potentially dose-limiting organ. The radiation dose to the bone marrow is usually calculated according to the MIRD scheme, where the accumulated activity in the bone marrow is calculated from the accumulated radioactivity of the radiopharmaceutical in the blood. This may underestimate the absorbed dose since stem cells express somatostatin receptors. We verified the blood-based method by comparing the activity in the blood with the radioactivity in bone marrow aspirates. Also, we evaluated the absorbed cross-dose from the source organs (liver, spleen, kidneys and blood), tumours and the so-called ''remainder of the body'' to the bone marrow. Bone marrow aspirates were drawn in 15 patients after treatment with [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate. Radioactivity in the bone marrow was compared with radioactivity in the blood drawn simultaneously. The nucleated cell fraction was isolated from the bone marrow aspirate and radioactivity was measured. The absorbed dose to the bone marrow was calculated. The results were correlated to the change in platelet counts 6 weeks after treatment. A strong linear correlation and high agreement between the measured radioactivities in the bone marrow aspirates and in the blood was found (r=0.914, p<0.001). No correlation between the calculated absorbed dose in the bone marrow and the change in platelets was found. There was a considerable contribution from other organs and the remainder of the body to the bone marrow absorbed dose. (1) After PRRT with [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate, the radioactivity concentration in the bone marrow is identical to that in the blood; (2) There is no significant binding of the radiopharmaceutical to bone marrow precursor stem cells; (3) The contribution of the cross dose from source organs and tumours to the bone

  10. Biodistribution and pharmacokinetics of 188Re-liposomes and their comparative therapeutic efficacy with 5-fluorouracil in C26 colonic peritoneal carcinomatosis mice

    Tsai CC

    2011-10-01

    Full Text Available Chia-Che Tsai1, Chih-Hsien Chang1, Liang-Cheng Chen1, Ya-Jen Chang1, Keng-Li Lan2, Yu-Hsien Wu1, Chin-Wei Hsu1, I-Hsiang Liu1, Chung-Li Ho1, Wan-Chi Lee1, Hsiao-Chiang Ni1, Tsui-Jung Chang1, Gann Ting3, Te-Wei Lee11Institute of Nuclear Energy Research, Taoyuan, 2Cancer Center, Taipei Veterans General Hospital, Taipei, 3National Health Research Institutes, Taipei, Taiwan, ROCBackground: Nanoliposomes are designed as carriers capable of packaging drugs through passive targeting tumor sites by enhanced permeability and retention (EPR effects. In the present study the biodistribution, pharmacokinetics, micro single-photon emission computed tomography (micro-SPECT/CT image, dosimetry, and therapeutic efficacy of 188Re-labeled nanoliposomes (188Re-liposomes in a C26 colonic peritoneal carcinomatosis mouse model were evaluated.Methods: Colon carcinoma peritoneal metastatic BALB/c mice were intravenously administered 188Re-liposomes. Biodistribution and micro-SPECT/CT imaging were performed to determine the drug profile and targeting efficiency of 188Re-liposomes. Pharmacokinetics study was described by a noncompartmental model. The OLINDA|EXM® computer program was used for the dosimetry evaluation. For therapeutic efficacy, the survival, tumor, and ascites inhibition of mice after treatment with 188Re-liposomes and 5-fluorouracil (5-FU, respectively, were evaluated and compared.Results: In biodistribution, the highest uptake of 188Re-liposomes in tumor tissues (7.91% ± 2.02% of the injected dose per gram of tissue [%ID/g] and a high tumor to muscle ratio (25.8 ± 6.1 were observed at 24 hours after intravenous administration. The pharmacokinetics of 188Re-liposomes showed high circulation time and high bioavailability (mean residence time [MRT] = 19.2 hours, area under the curve [AUC] = 820.4%ID/g*h. Micro-SPECT/CT imaging of 188Re-liposomes showed a high uptake and targeting in ascites, liver, spleen, and tumor. The results were correlated with

  11. Solar neutrino and 51Cr results from SAGE

    The Russian-American solar neutrino Experiment (SAGE) has carried out measurements of the capture rate of solar neutrinos on metallic gallium in a radiochemical experiment at the Baksan Neutrino Observatory during the period January 1990 to December 1994. The measured capture rate on 71Ga is 72+12/-10 (stat) +5/-7 (syst) SNU. This represents only 53-59 % of the predicted Standard Solar Model (SSM) rates. Taken together with the measurements of the other solar neutrino experiments, this deficit would appear to be best interpreted as due to Mikheyev-Smirnov-Wolfenstein neutrino oscillations. A measurement of the production rate of 71Ge by an intense 51Cr source to test the overall operation of the experiment showed the extraction efficiency was 0.95 ± 0.11 (stat) +0.05/-0.08 (syst), indicating that the experiment is operating as expected. (orig.)

  12. Treatment of transplanted tumor of lung adenocarcinoma A549 transfected by human somatostatin receptor subtype 2 (hsstr2) gene with 188Re-RC-160

    Background and aim: Radionuclide-labeled somatostatin analogues selectively target somatostatin receptor (SSTR)-expressing tumors as a basis for diagnosis and treatment of these tumors. To those tumors without somatostatin receptor expressed, the hSSTR2 gene was transfected. Express of the hSSTR2 receptor was imaging and the radiotherapeutic effect was evaluated with 188Re-RC-160. Methods: The stable hSSTR2-expressing A549 cells (pcDNA3-hSSTR2 A549) and non-somatostatin receptor expressing A549 cells (pcDNA3 A549) were selected by western blot. Later, a corresponding animal tumor model was established. Expression of the hSSTR2 reporter was imaged using 188Re-RC-160 recognition. Tumors were evaluated for somatostatin receptor expression using immunohistochemistry. The distribution of 188Re-RC-160 in the animal tumor model was measured and the inhibitory effects of 188Re-RC-160 were evaluated by measurement of tumor growth and hematoxylin and eosin and TdT mediated dUTP nick end labeling (TUNEL) staining. Results: In vivo radioimaging revealed specific targeting of 188Re-RC-160 to tumors derived from pcDNA3- hSSTR2 A549 cells, compared to those from pcDNA3 A549 cells. pcDNA3- hSSTR2 A549 tumor growth inhibition was significantly higher in the single 7.4 MBq 188Re-RC-160 treatment group than in the 2x7.4 MBq rhenium-188, RC-160 group, control group, and pcDNA3 A549 tumors (P188Re-RC-160), induced significantly increased tumor-growth inhibition compare with single 7.4 MBq 188Re-RC-160 treatment (P188Re-RC-160 could be effectively used for targeting therapy the A549-derived tumors exogenously expressing hSSTR2, which will offers a potential therapeutic strategy for the treatment of somatostatin receptor-negative cancers.

  13. Occupational doses in neuroendocrine tumors by using {sup 177}Lu DOTATATE; Doses ocupacionais em tratamento de tumores neuroendocrinos utilizando {sup 17'}7Lu DOTATATE

    Costa, Gustavo Coelho Alves; Sa, Lidia Vasconcellos de, E-mail: gustavo@ird.gov.b, E-mail: lidia@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2011-10-26

    This paper investigated the treatment of neuroendocrine tumors (abdominal tumors) using of {sup 177}Lu DOTATATE radiopharmaceutical which is a type of treatment presently used in the experimental form in Brazil and, therefore, not contemplated in norms or specific use. This research studied the occupational doses of this treatment and suggested guidelines or rules of procedures viewing the radiological protection of workers involved and the public. The treatment were followed up by using two types of radiation detection, one a scintillator and a Geiger-Muller, and the measurements were performed in a public hospital at Rio de Janeiro and the other in a private hospital at Sao Paulo. It was observed that the equivalent occupational doses can variate from 160 {mu}Sv to 450 {mu}Sv, in function of operator, of stage of manipulation, and of the administration method, which can be through the use of infusion pump or manual injection. The use of infusion pump is highly recommended and the hospitalization of the patient until the dose rate measured at 1 m does not surpass 20 {mu}Sv/h

  14. Synthesis and biological evaluation of a novel (177)Lu-DOTA-[Gly(3)-cyclized(Dap(4), (d)-Phe(7), Asp(10))-Arg(11)]α-MSH(3-13) analogue for melanocortin-1 receptor-positive tumor targeting.

    Lim, Jae Cheong; Hong, Young Don; Kim, Jin Ju; Choi, Sang Mu; Baek, Hye Suk; Choi, Sun-Ju

    2012-10-01

    In this study, a novel α-melanocyte stimulating hormone (α-MSH) analogue 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) coupled [Gly(3)-cyclized(Dap(4), (d)-Phe(7), Asp(10))-Arg(11)]α-MSH(3-13) (DOTA-GMSH) for melanocortin-1 receptor (MC-1R) targeting was newly synthesized, radiolabeled with (177)Lu, and in vitro and in vivo characterized. (177)Lu-labeled peptides were prepared with a high radiolabeling yield (>98%), and its Log p value was -2.89. No degradation was observed not only by serum incubation at 37°C for 7 days but also by an HPLC analysis of radioactive metabolites in urine. A cell binding assay revealed that an inhibitory concentration of 50% (IC(50)) of the peptide was 3.80 nM. The tumor-to-blood ratio, which was 14.27 at 2 hours p.i., was increased to 56.37 at 24 hours p.i., which means that the radiolabeled peptide was highly accumulated in a tumor and was rapidly cleared from the blood pool. We, therefore, conclude that (177)Lu-DOTA-GMSH has promising characteristics for application in nuclear medicine, namely for the diagnosis of MC-1R over-expressing tumors. PMID:22831553

  15. Production of 188-Re Sulphide Colloid for Knee Joints Arthritis Treatment and Acidity, Molar Ratio and Ultrasonic Time Optimization

    In this study, 188-Re sulphide colloid was synthesized as a radio synovectomy agent by reduction of sodium thiosulfate in the presence of perrhenate. The influences of the acidity, molar ratio and ultrasonic time on the colloid properties were investigated from 0.1 to 5 mol L-1; 5 to 70; and 10 to 60 min, respectively. The criteria for optimization of the influencing factors were the particle size and radiolabeling yield. Based on these factors the selected conditions were 1M HCl, thiosulfate to perrhenate molar ratio of 35 and 45 min for the ultrasonic time. The sizes of the particles were in the range of 1 to 5μm for more than 95% of the particles. The radionuclidic and radiochemical purity were found to be more than 99%. In addition, the synthesized colloid was stable for 5 days.

  16. Country report: Brazil. Development of Radiopharmaceuticals Based on 188Re and 90Y for Radionuclide Therapy at IPEN-CNEN/SP

    The overall objective of this CRP is to develop radiopharmaceuticals for targeted therapy using 188Re and 90Y and to study the performance of generators with long lived parent radionuclides as well as to validate the QC control procedures for estimating the purity of generator eluents. The CRP is expected to enhance the capability in production of 90Y and 188Re radiopharmaceuticals to meet the increasing demand of therapeutic products for clinical applications, in particular in Brazil. In this period efforts were made towards the assembling of 90Sr-90Y generators, quality control of 90Y, the labelling of DMSA(V) and anti-CD20 with 188Re and the labelling of Hydroxiapatite(HA) with 90Y. (author)

  17. Evaluation of safe use of 188Re-HEDP comparing urine data and whole body counting in gamma camera

    Cancer is the second more frequent cause of death, after cardiovascular disease, in developing countries. Most of adult patients with neoplasms will develop skeletal metastases that can lead to progressive pain. 188Re emits both beta particles suitable for therapy and a gamma ray (155 keV), adequate for diagnostic imaging in order to verify localization in the pain areas associated to metastatic process. The aim of this work was to correlate 188Re-HEDP dose estimations using biological samples and direct measures. All the patients had breast or prostate cancer, with bone metastases. Each patient received a tracer dose of 185 MBq of radiopharmaceutical. Urine samples were collected at 0-1, 1-2, 2-4 and, 4-6 hours post administration, and measured in dose calibrator. Whole body counts were acquired using a camera without collimator, window centered at 155 KeV, matrix 256 x 256, during 60 seconds. Data were obtained at 1 and 6 hours post administration with the patient in sitting position at 2 meter from the detector. Percentage of injected dose was calculated both for urine samples and image for each patient. The number of disintegrations was determined for organs in which higher concentration of activity was observed: those involved in the excretion, red marrow and the reminder of the body. Total doses were estimated using OLINDA/EXM software. Conclusions: Data showed that the organs chosen as more compromised during the tracer dose procedure received very low effective doses. A good correlation between calculations performed both for image and urine samples was obtained. Safety of the radiopharmaceutical was also verified using this method. (author)

  18. A YAP camera for the biodistribution of {sup 188}Re conjugated with Hyaluronic-Acid in 'in vivo' systems

    Antoccia, A. [Department of Biology, Roma3 University (Italy); INFN, Roma3 (Italy); Baldazzi, G. [Department of Physics, Bologna University (Italy); INFN, Bologna (Italy); Banzato, A. [Department of Oncology and Surgical Sciences, Padova University (Italy); Bello, M. [INFN, National Laboratories, Legnaro (Italy); Department of Physics, Padova University (Italy); Boccaccio, P. [INFN, National Laboratories, Legnaro (Italy); Bollini, D. [Department of Physics, Bologna University (Italy); INFN, Bologna (Italy); De Notaristefani, F. [INFN, Roma3 (Italy); Department of Electronic Engineering, Roma3 University and INFN (Italy); Mazzi, U. [Department of Pharmaceutical Sciences, Padova University (Italy); Alafort, L.M. [Department of Pharmaceutical Sciences, Padova University (Italy); Moschini, G. [INFN, National Laboratories, Legnaro (Italy); Department of Physics, Padova University (Italy); Navarria, F.L. [Department of Physics, Bologna University (Italy); INFN, Bologna (Italy); Pani, R. [Department of Experimental Medecine and Pathology, Roma1 University (Italy); INFN, Roma1 (Italy); Perrotta, A. [INFN, Bologna (Italy)]. E-mail: perrotta@bo.infn.it; Rosato, A. [Department of Oncology and Surgical Sciences, Padova University (Italy); Istituto Oncologico Veneto, Padova (Italy); Tanzarella, C. [Department of Biology, Roma3 University (Italy); Uzunov, N.M. [INFN, National Laboratories, Legnaro (Italy); Dept. Natural Sciences, Shumen Univ. (Bulgaria)

    2007-02-01

    The aim of the SCINTIRAD experiment is to determine the radio-response of {sup 188}Rhenium (Re) in in vitro cells and the biodistribution in different organs of in vivo mice, and subsequently to assess the therapeutic effect on liver tumours induced in mice. Both the {gamma}- and {beta}- emissions of {sup 188}Re have been exploited in the experiment. The in vivo biodistribution in mice was studied also with a {gamma}-camera using different parallel hole collimators. In the {sup 188}Re spectrum, while the 155 keV {gamma}-peak is useful for imaging, the photons emitted at larger energies and the {beta}-particles act as noise in the image reconstruction. The {gamma}-cameras previously used to image biodistributions obtained with {sup 99}Tc are, therefore, not optimized for use with {sup 188}Re. A new setup of the {gamma}-camera has been studied for {sup 188}Re: 66x66 YAP:Ce crystals (0.6x0.6x10 mm{sup 3}, 5 {mu}m optical insulation) guarantee a FOV of 40x40 mm{sup 2}, a Hamamatsu R2486 PSPMT, 3 in. diameter, converts their light into an electrical signal and allows reconstructing the spatial coordinates of the light spot; incoming photon directions are selected through a lead collimator with 1.5 mm diameter hexagonal holes, 0.18 mm septa, 40 mm thickness. Using this setup, results have been obtained both with {sup 99}Tc filled and {sup 188}Re filled capillaries and wells. The energy spectrum of the collected photons and the spatial resolutions obtainable with the {sup 188}Re source will be presented.

  19. Formulation and evaluation of freeze-dried DOTMP kit for the preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP at the hospital radiopharmacy

    Das, Tapas; Banerjee, Sharmila [Bhabha Atomic Research Centre, Radiopharmaceuticals Chemistry Section, Mumbai (India); Chakraborty, Sudipta [Bhabha Atomic Research Centre, Isotope Production and Applications Div., Mumbai (India); Sarma, Haladhar D. [Bhabha Atomic Research Centre, Radiation Biology and Health Sciences Div., Mumbai (India)

    2015-07-01

    The objective of the present work is to develop and evaluate freeze-dried DOTMP kit, which could be utilized for the convenient and single-step preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP, both of which have shown potential as alternative agents for metastatic bone pain palliation. Freeze-dried DOTMP kits, each comprising a lyophilized mixture of 20 mg DOTMP and 8.75 mg NaOH, were prepared. The kits were used for the preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP complexes. The agents were prepared by dissolving the lyophilized powder in 1 mL of normal saline and incubating with {sup 177}LuCl{sub 3} or {sup 153}SmCl{sub 3}, produced in-house, for 15 min at room temperature. Pharmacokinetic behavior and biological distribution of the agents were studied by carrying out biodistribution as well as scintigraphic studies in normal male Wistar rats. Shelf-life of the freeze-dried kits was also ascertained. Clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP complexes, comprising up to 3.7 GBq (100 mCi) of activity, were prepared with > 99% radiochemical purity using the freeze-dried kits. The complexes exhibited high in vitro stability when stored at room temperature. Biological studies showed selective skeletal accumulation and insignificant uptake of the radiotracers in any of the vital organs/tissue. The non-accumulated activity exhibited primary urinary clearance. The kits had a shelf-life of 2 years when stored at 4 C temperature. Freeze-dried DOTMP kits, suitable for the preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP, have been developed and the radiochemical and biological behaviors of the radiolabeled agents have been studied. The use of the kit at the hospital radiopharmacy is expected to make the preparations easy and convenient. This in turn will enable the widespread dissemination of these promising agents towards their application for regular use.

  20. In vitro and in vivo evaluation of 177Lu- and 9Y-labeled E. coli heat-stable enterotoxin for specific targeting of uroguanylin receptors on human colon cancers

    The human E. coli heat-stable enterotoxin (STh, amino acid sequence N1SSNYCCELCCNPACTGCY19) binds specifically to the guanylate cyclase C (GC-C) receptor, which is present in high density on the apical surface of normal intestinal epithelial cells as well as on the surface of human colon cancer cells. Analogs of STh are currently being used as vectors targeting human colon cancers. Previous studies in our laboratory have focused on development of 111Indium-labeled STh analogs for in vivo imaging applications. Here, we extend the scope of this work to include targeting of the therapeutic radionuclides 9Y and 177Lu. The peptide DOTA-F19-STh(1-19) was synthesized using conventional Fmoc-based solid-phase techniques and refolded in dilute aqueous solution. The peptide was purified by RP-HPLC and characterized by MALDI-TOF MS and in vitro receptor binding assay. The DOTA-conjugate was metallated with nonradioactive Lu(III)Cl3 and Y(III)Cl3, and IC5 values of 2.6±0.1 and 4.2±0.9 nM were determined for the Lu- and Y-labeled peptides, respectively. 177Lu(III)Cl3 and 9Y(III)Cl3 labeling yielded tracer preparations that were inseparable by C18 RP-HPLC, indicating that putative differences between Lu-, Y- and In coordination spheres are not observed in the context of labeled STh peptides. In vivo biodistribution studies of the 177Lu-labeled peptide in severe combined immunodeficient (SCID) mice bearing T-84 human cancer tumor xenografts showed rapid clearance from the bloodstream, with >90 %ID in the urine at 1 h pi. Localization of the tracer within tumor xenografts was 1.86±0.91 %ID/g at 1 h pi, a value higher than for all other tissues with the exception of kidney (2.74±0.24 %ID/g). At 24 h pi, >98 %ID was excreted into the urine, and 0.35±0.23 %ID/g remained in tumor, again higher than in all other tissues except kidney (0.91±0.46 %ID/g). Biodistribution results at 24 h pi for the 9Y-labeled peptide mirrored those for the 177Lu analog, in agreement with the

  1. Formulation and evaluation of freeze-dried DOTMP kit for the preparation of clinical-scale 177Lu-DOTMP and 153Sm-DOTMP at the hospital radiopharmacy

    The objective of the present work is to develop and evaluate freeze-dried DOTMP kit, which could be utilized for the convenient and single-step preparation of clinical-scale 177Lu-DOTMP and 153Sm-DOTMP, both of which have shown potential as alternative agents for metastatic bone pain palliation. Freeze-dried DOTMP kits, each comprising a lyophilized mixture of 20 mg DOTMP and 8.75 mg NaOH, were prepared. The kits were used for the preparation of clinical-scale 177Lu-DOTMP and 153Sm-DOTMP complexes. The agents were prepared by dissolving the lyophilized powder in 1 mL of normal saline and incubating with 177LuCl3 or 153SmCl3, produced in-house, for 15 min at room temperature. Pharmacokinetic behavior and biological distribution of the agents were studied by carrying out biodistribution as well as scintigraphic studies in normal male Wistar rats. Shelf-life of the freeze-dried kits was also ascertained. Clinical-scale 177Lu-DOTMP and 153Sm-DOTMP complexes, comprising up to 3.7 GBq (100 mCi) of activity, were prepared with > 99% radiochemical purity using the freeze-dried kits. The complexes exhibited high in vitro stability when stored at room temperature. Biological studies showed selective skeletal accumulation and insignificant uptake of the radiotracers in any of the vital organs/tissue. The non-accumulated activity exhibited primary urinary clearance. The kits had a shelf-life of 2 years when stored at 4 C temperature. Freeze-dried DOTMP kits, suitable for the preparation of clinical-scale 177Lu-DOTMP and 153Sm-DOTMP, have been developed and the radiochemical and biological behaviors of the radiolabeled agents have been studied. The use of the kit at the hospital radiopharmacy is expected to make the preparations easy and convenient. This in turn will enable the widespread dissemination of these promising agents towards their application for regular use.

  2. 188Re-HEDP combined with capecitabine in hormone-refractory prostate cancer patients with bone metastases: a phase I safety and toxicity study

    Lam, Marnix G.E.H.; Bosma, Tjitske B.; Rijk, Peter P. van; Zonnenberg, Bernard A.

    2009-01-01

    Purpose 188Re-HEDP is indicated for the treatment of pain in patients with painful osteoblastic bone metastases, including hormone-refractory prostate cancer patients. Efficacy may be improved by adding chemotherapy to the treatment regimen as a radiation sensitizer. The combination of 188Re-HEDP and capecitabine (Xeloda®) was tested in a clinical phase I study. Methods Patients with hormone-refractory prostate cancer were treated with capecitabine for 14 days (oral twice daily in a dose esca...

  3. Variations in absorbed doses from 51Cr in investigations with labelled erythrocytes

    In nuclear medicine 51Cr labelled red blood cells are used to determine erythrocyte volume, red cell survival, or the site of red cell destruction. The author examined the variations in adsorbed doses from 51Cr in 77 patients with various diseases in whom erythrokinetic investigations were performed for diagnostic purposes. Autologous erythrocytes were incubated with Na2CrO4 (37 kBq (1.0 uCi) 51Cr/kg body weight) and injected intravenously. 51Cr activity in blood was then followed for 10 weeks. 51Cr activity over liver, spleen, and sacrum and whole-body retention of 51Cr were measured for the same period. A compartmental model was assumed to describe the kinetics of 51Cr tagged to red blood cells. It is a noncirculating linear model with the compartments represented by organs (spleen, liver, bone, residual body) rather than physiological compartments. The computer program SAAM-25 was used to provide the kinetic parameters and the organ retention functions. From the cumulated activities of the source regions, organ doses and effective dose equivalents were calculated according to the MIRD concepts. The highest organ doses were found for spleen, liver, and red marrow. The calculated dose values for 51Cr found in this study confirm only partly the values reported in ICRP Publication 17, but are higher up to a factor of 9 for some organs. 16 references, 1 figure, 3 tables

  4. Uptake studies of environmentally hazardous 51Cr in Mung beans

    Attempt has been made to study the accumulation behaviour of a common plant, Mung bean (Vigna radiata) towards Cr(III) and Cr(VI) to have an insight on the migration and bio-magnification of Cr. For this purpose healthy germinated Mung bean seeds were sown in the sand in the presence of Hoagland's nutrient solution containing measured amount of K251Cr2O7 and 51Cr(NO3)3.9H2O. Growth rate was also studied in the presence and absence of phosphate salts in the medium. It has been found that the transfer of chromium from soil to plant is significantly low (maximum 5% for both Cr(III) and Cr(VI)). Maximum accumulation of Cr occurs in the root with respect to the total chromium accumulation by the plant. Other parts of the Mung bean plant, e.g. cotyledons, shoot and leaves, show negligible accumulation. Therefore, the chance of direct intake of Cr through food as well as through the grazing animals to human body is less. - The chance of bio-magnification of Cr(III) or Cr(VI) to human body via direct or indirect intake of Mung bean is negligible

  5. Outcome of peptide receptor radionuclide therapy with {sup 177}Lu-octreotate in advanced grade 1/2 pancreatic neuroendocrine tumours

    Ezziddin, Samer; Khalaf, Feras; Vanezi, Maria; Haslerud, Torjan; Zreiqat, Abdullah Al; Biersack, Hans-Juergen; Sabet, Amir [University Hospital Bonn, Department of Nuclear Medicine, Bonn (Germany); Mayer, Karin [University Hospital, Department of Internal Medicine and Oncology, Bonn (Germany); Willinek, Winfried [University Hospital, Department of Radiology, Bonn (Germany)

    2014-05-15

    The clinical benefit of peptide receptor radionuclide therapy (PRRT) in patients with pancreatic neuroendocrine tumours (pNET) has not yet been well described and defined in its full extent due to limited data in this tumour subgroup. This study was intended to obtain robust, comparative data on the outcome and toxicity of standardized PRRT with {sup 177}Lu-octreotate in a well-characterized population of patients with advanced pNET of grade 1/2 (G1/2). We retrospectively analysed a cohort of 68 pNET patients with inoperable metastatic disease consecutively treated with {sup 177}Lu-octreotate (four intended cycles at 3-monthly intervals; mean activity per cycle 8.0 GBq). Of these 68 patients, 46 (67.6 %) had documented morphological tumour progression during the 12 months before initiation of treatment, and PRRT was the first-line systemic therapy in 35 patients (51.5 %). Response was evaluated according to modified Southwest Oncology Group (SWOG) criteria and additionally with Response Criteria in Solid Tumors (RECIST) 1.1. Survival was analysed using Kaplan-Meier curves and Cox proportional hazards model for univariate and multivariate analyses. Toxicity was assessed by standard follow-up laboratory work-up including blood count, and liver and renal function, supplemented with serial {sup 99m}Tc-DTPA clearance measurements. The median follow-up period was 58 months (range 4 - 112). Reversible haematotoxicity (grade 3 or more) occurred in four patients (5.9 %). No significant nephrotoxicity (grade 3 or more) was observed. Treatment responses (SWOG criteria) consisted of a partial response in 41 patients (60.3 %), a minor response in 8 (11.8 %), stable disease in 9 (13.2 %), and progressive disease in 10 (14.7 %). Median progression-free survival (PFS) and overall survival (OS) were 34 (95 % CI 26 - 42) and 53 months (95 % CI 46 - 60), respectively. A G1 proliferation status was associated with longer PFS (p = 0.04) and OS (p = 0.044) in the multivariate analysis

  6. Feasibility and utility of re-treatment with {sup 177}Lu-DOTATATE in GEP-NENs relapsed after treatment with {sup 90}Y-DOTATOC

    Severi, Stefano; Sansovini, Maddalena; Ianniello, Annarita; Nicolini, Silvia; Caroli, Paola; Paganelli, Giovanni [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Nuclear Medicine Unit, Meldola, FC (Italy); Bodei, Lisa [European Institute of Oncology, Division of Nuclear Medicine, Milan (Italy); Ibrahim, Toni [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Osteoncology and Rare Tumors Center, Meldola (Italy); Di Iorio, Valentina [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Oncology Pharmacy Laboratory, Meldola (Italy); D' Errico, Vincenzo [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Medical Physics Unit, Meldola (Italy); Monti, Manuela [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Unit of Biostatistics and Clinical Trials, Meldola (Italy)

    2015-12-15

    Peptide receptor radionuclide therapy (PRRT) is a valid therapy for grade 1/2 gastroenteropancreatic (GEP) neuroendocrine neoplasms (NENs). Although a median progression-free survival (PFS) of more than 20 months is frequently observed, the majority of patients relapse after 2 - 3 years. In the present study, we investigated the use of low dosage re-treatment with {sup 177}Lu-DOTATATE (Lu-PRRT) in patients with GEP-NENs who relapsed after treatment with {sup 90}Y-DOTATOC (Y-PRRT). Upon tumour progression, 26 patients with a PFS of at least 12 months after Y-PRRT were consecutively enrolled in a phase II study of re-treatment with Lu-PRRT. All patients had preserved kidney and haematological parameters and received 14.8 - 18.5 GBq of Lu-PRRT in four or five cycles. The disease control rate (DCR), toxicity, PFS and prognostic factors were evaluated. Median total activity of Lu-PRRT was 16.5 GBq in five cycles. The DCR was 84.6 %, median PFS was 22 months (95 % CI 16 months - not reached) compared to 28 months (95 % CI 20 - 36 months) after Y-PRRT. Tumour burden and number of liver metastases were important prognostic factors. Toxicity was mild after Lu-PRRT re-treatment in the majority of patients, with only two patients with grade 2 and one with grade 3 bone marrow toxicity; one patient had grade 2 and one grade 3 renal toxicity. Patients with GEP-NEN who have previously responded to Y-PRRT are suitable candidates for Lu-PRRT re-treatment on progression. Although our sample size was limited, low-dosage Lu-PRRT was safe, and led to DCR and PFS rates comparable with those observed when Y-PRRT was used as primary treatment. (orig.)

  7. Influence of biological assay conditions on stability assessment of radiometal-labelled peptides exemplified using a {sup 177}Lu-DOTA-minigastrin derivative

    Ocak, Meltem [Clinical Department of Nuclear Medicine, Medical University Innsbruck, A-6020, Innsbruck (Austria); Department of Pharmaceutical Technology, Pharmacy Faculty, Istanbul University, 34116, Istanbul (Turkey); Helbok, Anna; Guggenberg, Elisabeth von [Clinical Department of Nuclear Medicine, Medical University Innsbruck, A-6020, Innsbruck (Austria); Ozsoy, Y. [Department of Pharmaceutical Technology, Pharmacy Faculty, Istanbul University, 34116, Istanbul (Turkey); Kabasakal, Levent [Department of Nuclear Medicine, Cerrahpasa Medical Faculty, 34098, Istanbul (Turkey); Kremser, Leopold [Division of Clinical Biochemistry, Protein Micro-Analysis Facility, Biocenter, Medical University Innsbruck, A-6020, Innsbruck (Austria); Decristoforo, Clemens, E-mail: clemens.decristoforo@uki.a [Clinical Department of Nuclear Medicine, Medical University Innsbruck, A-6020, Innsbruck (Austria)

    2011-02-15

    Introduction: Lack of correlation between in vitro and in vivo stability is a general problem for the development of radiopeptides especially in the case of minigastrin derivatives for therapeutic applications. In this study, we compared the influence of experimental conditions on radiopeptide stability results in vitro using a model Minigastrin (MG) analogue labelled with Lu-177. Additionally, we attempted to characterize the main serum enzymatic cleavage sites by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) analysis. Methods: In vitro stability of a DOTA-minigastrin derivative ({sup 177}Lu-DOTA-His-His-Glu-Ala-Tyr-Gly-Trp-NIe-Asp-Phe-NH{sub 2}) was tested in serum, rat tissue homogenates and two different standardised enzymatic mixtures. Quantification of the metabolised radiopeptides at different time intervals was performed using reversed-phase high-performance liquid chromatography (RP-HPLC). Metabolites were characterised by MALDI-TOF-MS. Urine was collected after 15 min p.i. into the mice and compared with in vitro metabolites by RP-HPLC. Results: Faster degradation of the radiopeptide was found in blood in comparison with plasma and serum incubation and in components from rats faster than from human origin. Fast degradation was observed in kidney and liver homogenates as well as in standardised enzymatic mixtures, also revealing variations in the metabolic profile. In urine, no intact peptide was detected already 5 min post injection. MALDI-TOF-MS revealed major cleavage sites at the carboxy terminus of the peptide. Conclusion: Very variable results may be found when different kind of incubation media for testing radiopeptide stabilities is used. Serum incubation studies may overestimate stability; therefore, results should be interpreted with care and combined with alternative in vitro and in vivo investigations.

  8. Rapid blood clearance and lack of long-term renal toxicity of {sup 177}Lu-DOTATATE enables shortening of renoprotective amino acid infusion

    Kashyap, Raghava; Eu, Peter [Centre for Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne (Australia); Jackson, Price [Peter MacCallum Cancer Centre, Department of Physical Sciences, Melbourne (Australia); Hofman, Michael S.; Hicks, Rodney J. [Centre for Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne (Australia); The University of Melbourne, Departments of Medicine and Radiology, Melbourne (Australia); Beauregard, Jean-Mathieu [Universite Laval, Department of Radiology, Quebec City (Canada); Zannino, Diana [Peter MacCallum Cancer Centre, Department of Biostatistics and Clinical Trials, Melbourne (Australia)

    2013-12-15

    The aim of the study was to investigate the feasibility of shortening the recommended 4-h renoprotective amino acid infusion in patients receiving peptide receptor chemoradionuclide therapy (PRCRT) using radiosensitizing 5-fluorouracil. We evaluated the clearance of radiopeptide from the blood, long-term nephrotoxicity in patients undergoing PRCRT with the conventional 4-h amino acid infusion and renal uptake in patients receiving an abbreviated infusion. The whole-blood clearance of {sup 177}Lu-DOTA-octreotate (LuTate) was measured in 13 patients receiving PRCRT. A retrospective analysis of short-term and long-term changes in glomerular filtration rate (GFR) in 96 consecutive patients receiving a 4-h infusion was performed. Renal LuTate retention estimated using quantitative SPECT/CT in 22 cycles delivered with a 2.5-h amino acid infusion was compared with that in 72 cycles with the 4-h infusion. LuTate demonstrated biexponential blood clearance with an initial clearance half-time of 21 min. Approximately 88 % of blood activity was cleared within 2 h. With the 4-h protocol, there was no significant change in GFR (1.2 ml/min mean increase from baseline; 95 % CI -6.9 to 4.4 ml/min) and no grade 3 or 4 nephrotoxicity at the end of induction PRCRT. The long-term decline in GFR after a median follow up of 22 months was 2.2 ml/min per year. There was no significant difference in the renal LuTate retention measured in patients receiving a 2.5-h amino acid infusion compared to those who had a 4-h infusion. The greatest renal exposure to circulating radiopeptide occurs in the first 1 - 2 h after injection. This, combined with the safety of LuTate PRCRT, allows consideration of an abbreviated amino acid infusion, increasing patient convenience and reducing human resource allocation. (orig.)

  9. Feasibility and utility of re-treatment with 177Lu-DOTATATE in GEP-NENs relapsed after treatment with 90Y-DOTATOC

    Peptide receptor radionuclide therapy (PRRT) is a valid therapy for grade 1/2 gastroenteropancreatic (GEP) neuroendocrine neoplasms (NENs). Although a median progression-free survival (PFS) of more than 20 months is frequently observed, the majority of patients relapse after 2 - 3 years. In the present study, we investigated the use of low dosage re-treatment with 177Lu-DOTATATE (Lu-PRRT) in patients with GEP-NENs who relapsed after treatment with 90Y-DOTATOC (Y-PRRT). Upon tumour progression, 26 patients with a PFS of at least 12 months after Y-PRRT were consecutively enrolled in a phase II study of re-treatment with Lu-PRRT. All patients had preserved kidney and haematological parameters and received 14.8 - 18.5 GBq of Lu-PRRT in four or five cycles. The disease control rate (DCR), toxicity, PFS and prognostic factors were evaluated. Median total activity of Lu-PRRT was 16.5 GBq in five cycles. The DCR was 84.6 %, median PFS was 22 months (95 % CI 16 months - not reached) compared to 28 months (95 % CI 20 - 36 months) after Y-PRRT. Tumour burden and number of liver metastases were important prognostic factors. Toxicity was mild after Lu-PRRT re-treatment in the majority of patients, with only two patients with grade 2 and one with grade 3 bone marrow toxicity; one patient had grade 2 and one grade 3 renal toxicity. Patients with GEP-NEN who have previously responded to Y-PRRT are suitable candidates for Lu-PRRT re-treatment on progression. Although our sample size was limited, low-dosage Lu-PRRT was safe, and led to DCR and PFS rates comparable with those observed when Y-PRRT was used as primary treatment. (orig.)

  10. Rapid blood clearance and lack of long-term renal toxicity of 177Lu-DOTATATE enables shortening of renoprotective amino acid infusion

    The aim of the study was to investigate the feasibility of shortening the recommended 4-h renoprotective amino acid infusion in patients receiving peptide receptor chemoradionuclide therapy (PRCRT) using radiosensitizing 5-fluorouracil. We evaluated the clearance of radiopeptide from the blood, long-term nephrotoxicity in patients undergoing PRCRT with the conventional 4-h amino acid infusion and renal uptake in patients receiving an abbreviated infusion. The whole-blood clearance of 177Lu-DOTA-octreotate (LuTate) was measured in 13 patients receiving PRCRT. A retrospective analysis of short-term and long-term changes in glomerular filtration rate (GFR) in 96 consecutive patients receiving a 4-h infusion was performed. Renal LuTate retention estimated using quantitative SPECT/CT in 22 cycles delivered with a 2.5-h amino acid infusion was compared with that in 72 cycles with the 4-h infusion. LuTate demonstrated biexponential blood clearance with an initial clearance half-time of 21 min. Approximately 88 % of blood activity was cleared within 2 h. With the 4-h protocol, there was no significant change in GFR (1.2 ml/min mean increase from baseline; 95 % CI -6.9 to 4.4 ml/min) and no grade 3 or 4 nephrotoxicity at the end of induction PRCRT. The long-term decline in GFR after a median follow up of 22 months was 2.2 ml/min per year. There was no significant difference in the renal LuTate retention measured in patients receiving a 2.5-h amino acid infusion compared to those who had a 4-h infusion. The greatest renal exposure to circulating radiopeptide occurs in the first 1 - 2 h after injection. This, combined with the safety of LuTate PRCRT, allows consideration of an abbreviated amino acid infusion, increasing patient convenience and reducing human resource allocation. (orig.)

  11. Influence of biological assay conditions on stability assessment of radiometal-labelled peptides exemplified using a 177Lu-DOTA-minigastrin derivative

    Introduction: Lack of correlation between in vitro and in vivo stability is a general problem for the development of radiopeptides especially in the case of minigastrin derivatives for therapeutic applications. In this study, we compared the influence of experimental conditions on radiopeptide stability results in vitro using a model Minigastrin (MG) analogue labelled with Lu-177. Additionally, we attempted to characterize the main serum enzymatic cleavage sites by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) analysis. Methods: In vitro stability of a DOTA-minigastrin derivative (177Lu-DOTA-His-His-Glu-Ala-Tyr-Gly-Trp-NIe-Asp-Phe-NH2) was tested in serum, rat tissue homogenates and two different standardised enzymatic mixtures. Quantification of the metabolised radiopeptides at different time intervals was performed using reversed-phase high-performance liquid chromatography (RP-HPLC). Metabolites were characterised by MALDI-TOF-MS. Urine was collected after 15 min p.i. into the mice and compared with in vitro metabolites by RP-HPLC. Results: Faster degradation of the radiopeptide was found in blood in comparison with plasma and serum incubation and in components from rats faster than from human origin. Fast degradation was observed in kidney and liver homogenates as well as in standardised enzymatic mixtures, also revealing variations in the metabolic profile. In urine, no intact peptide was detected already 5 min post injection. MALDI-TOF-MS revealed major cleavage sites at the carboxy terminus of the peptide. Conclusion: Very variable results may be found when different kind of incubation media for testing radiopeptide stabilities is used. Serum incubation studies may overestimate stability; therefore, results should be interpreted with care and combined with alternative in vitro and in vivo investigations.

  12. Labeling , in -Vitro Stability and Biological Distribution of 188 Re- Ethylenediamine- N,N,N,N,-tetrakis (Methylene Phosphonic) Acid complex

    Labeling of ethylenediamine-N,N,N,N-tetrakis (methylene phosphonic) acid (EDTMP) with rhenium -188 was investigated. Stannous chloride was used as a reducing agent for the reduction of 188 ReO4. Dependence of the yield of 188Re-EDTMP complex upon the concentration of EDTMP, tin (II) content, reaction time, amount of antioxidant, Ph, reaction temperature and adding of carrier was examined. The optimum condition that given high labeling yield of 188 Re-EDTMP complex (95.8% with carrier - free rhenium and 97% with carrier-added rhenium) was achieved using 40 mg EDTMP, 0.8 mg Sn(II),Ph=0.8, reaction temperature 100 degree and 5 min reaction time. the amount of carrier added equal to 200 μg KReO4 Furthermore, 188Re-EDTMP complex prepared at 100 degree is more stable than that prepared at 30 degree and the carrier added 188R-EDTMP complex is more stable than the no carrier added complex

  13. Technological line for production of carrier-free 188Re in the form of sterile, isotonic solution of sodium perrhenate (VII)

    Full text: Radiometric properties of 188Re create convenient condition for medical application of this radionuclide. A big interest has arisen concerning the use of 188Re for radioimmunotherapy, radionuclide synovectomy and bone pain palliation. This is due to the favorable characteristic of 188Re (T1/2 = 16,98 h), emission β- particles with an average energy of 764 keV and emission of 155 eV gamma photon (15%, γ-rays), which permits the in vivo biodistribution evaluation of 188Re-labeled ligands with gamma camera. Radionuclide 188Re is produced in results of 188W decay. Tungsten-188 is obtained by neutron activation of 186W according to nuclear reaction 186W (n,γ) → 187W (n,γ) → 188W. At the Radioisotope Centre Polatom the technology for production of sterile and isotonic solution of 188Re has been elaborated. High specific activity 188W is imported from RIAR, Russia with following specification; sodium tungstenate in sodium hydroxide solution, 188W specific activity 195 GBq/g, 187W to 188W activity ratio 0,23%, total gamma emitters to 188W activity ratio 0,3%, solvent concentration (sodium hydroxide) 0,24 mol/l and tungsten concentration 50 g/l. The solution of sodium tungstenate is processing in technological line consisting of five lead-shielded chambers in which following operations are carried out. 1. Unloading of active material 2. Filling of 188W solution on alumina column 3. Elution of 188Re in form sodium perrhenate 4. Concentration of eluate 5. Proportioning of 188Re solution to vials and its sterilization 6. Vials removal from technological line. Alumina used for filling the generator columns was first activated using 0,9% NaCl in 0,001M HCl and 32% HCl to obtain final pH of about 3. Tungsten 188W in the form of tungstenic acid was slowly loaded on the column (flow 0,1 ml/min). After 188W deposition the alumina column was washed with 0,9% NaCl to remove the unbound 188W. The adsorption capacity of alumina has been studied and the optimal

  14. Three-dimensional personalized dosimetry for 188Re liver selective internal radiation therapy based on quantitative post-treatment SPECT studies

    Shcherbinin, S.; Grimes, J.; Bator, A.; Cwikla, J. B.; Celler, A.

    2014-01-01

    We demonstrate that accurate patient-specific distributions of microspheres labeled with 188Re and resulting absorbed doses can be obtained from single-photon emission computed tomography (SPECT) studies performed after 188Re selective internal radiation therapy when accurate correction methods are employed in image reconstruction. Our quantitative image reconstruction algorithm includes corrections for attenuation, resolution degradations and scatter as well as a window-based compensation for contamination. The procedure has been validated using four phantom experiments containing an 18 ml cylindrical source (82-93 MBq of 188Re activity) simulating a liver tumor. In addition, we applied our approach to post-therapy SPECT studies of ten patients with progressive primary or metastatic liver carcinomas. Our quantitative algorithm accurately (within 9%) recovered 188Re activity from four phantom experiments. In addition, for two patients that received three scans, deviations remained consistent between the measured and the reconstructed activities that were determined from studies with differing severity of the dead-time effect. The analysis of absorbed doses for patient studies allowed us to hypothesize that D90 (the minimum dose received by 90% of the tumor volume) may be a reliable metric relating therapy outcomes to the calculated doses. Among several considered metrics, only D90 showed statistically significant correlation with the overall survival.

  15. Cellular metabolic responses of PET radiotracers to {sup 188}Re radiation in an MCF7 cell line containing dominant-negative mutant p53

    Cheon, Gi Jeong [Laboratory of Nuclear Medicine Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of) and Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)]. E-mail: larry@kcch.re.kr; Chung, Hye-Kyung [Laboratory of Nuclear Medicine Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Choi, Jung-A [Laboratory of Radiation Experimental Therapeutics, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Lee, Su-Jae [Laboratory of Radiation Experimental Therapeutics, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Ahn, Soon-Hyuk [Laboratory of Nuclear Medicine Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Lee, Tae-Sup [Laboratory of Nuclear Medicine Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Choi, Chang Woon [Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Lim, Sang Moo [Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)

    2007-05-15

    We investigated the relations between the cell uptakes of metabolic radiotracers and {beta}-radiation pretreatment using a dominant mutant p53 (p53mt) cell line to evaluate the effects of p53 genes on {sup 18}F labeled positron emission tomography (PET) radiotracer uptakes. Methods: pCMV-Neo-Bam (control), which contains a neo-resistance marker, and p53 dominant-negative mutant expression constructs were stably transfected into MCF7 cell line. Cells were plated in 24-well plates at 1.0x10{sup 5} cells for 18 h. Rhenium-188 ({sup 188}Re) (a beta emitter) was added to the medium (3.7, 18.5, 37 MBq) and incubated for 24 h. We performed gamma-counting to determine the cellular uptakes of 2-[{sup 18}F]fluoro-2-deoxy-D-glucose (FDG), o-(2-[{sup 18}F]fluoroethyl)-L-tyrosine (FET) and 2'-[{sup 18}F]fluoro-2'-deoxythymidine (FLT) (370 kBq, 60 min). Cell viabilities were determined by trypan blue staining and flow cytometry. Results: p53mt cells showed 1.5-2-fold higher FDG uptake than wild-type p53 cells in basal condition, and the difference of FDG uptake was greater after {sup 188}Re treatment (P<.01). FET uptake increased with {sup 188}Re dose without a significant difference between p53 statuses. p53mt cells showed lower FLT uptake than wild-type p53 cells in basal condition, and the difference of FLT uptake was greater after {sup 188}Re treatment. By cell viability testing and FACS analysis, p53mt cells showed lower viability and a larger apoptotic fraction (sub-G1) than wild-type p53 cells after {sup 188}Re treatment. Conclusion: We speculate that p53 dysfunction increases glucose and decreases thymidine metabolism in cancer cells and that this may be exaggerated by {sup 188}Re {beta}-radiation. Our findings suggest that FDG could reflect tumor viability and malignant potential after {sup 188}Re {beta}-radiation treatment, whereas FLT could be a more useful PET radiotracer for assessing therapeutic response to {beta}-radiation, especially in cancer cells

  16. Study of different absorbent materials for the preparation of generator systems of 99Mo - 99mTc and 188W-188Re

    Amongst some currently radioisotopes, 99mTc and 188Re present adequate decay properties for use in Nuclear Medicine. In the current times the most diagnosis examinations are performed with 99mTc and 188Re is one radioisotope of potential use in therapy techniques. The objective of this work consists of determining the capacity of some adsorbent materials for retention of molybdenum and tungsten, aiming the optimization of generator systems of 99Mo-99mTc and 188W-188Re with suitable characteristics for application in Nuclear Medicine. Known amounts, in mass, of molybdenum and tungsten were percolated through different chromatographic columns containing different commercial adsorbent materials such as: PZC (poly-zirconium compound), acid alumina and calcinated alumina used in the routine preparation of 99Mo-99mTc generators at IPEN. The tungsten (188W), as well the PZC used in this project, supplied by Russia and Japan, respectively, through the International Atomic Energy Agency (IAEA) and used without any previous preparation. Also trace amounts of 99Mo and 188W were added to the initial solutions and the generators were assembled. The 99Mo-99mTc generators were then eluted with known volumes of 0.9% NaCl solution every 24 hours whereas the 188W-188Re generators were eluted every 48 hours. The eluted samples were analyzed by Gamma Spectroscopy and later submitted to quality control evaluation. The results showed that the PZC presents superior retention capacity for Mo of 97.50mg Mo/gPZC, higher than in acid and calcinated alumina, however the elution efficiency at lower pHs is not so high. With regards to the experiments carried out with 188W and alumina, it was verified that the elution efficiency of 188Re was not reproducible and the retention capacity of W was 90.23mgW/gAl2O3 at pH 7. (author)

  17. Therapeutic efficacy of 188Re-MN-16ET lipiodol in an animal model of hepatocellular carcinoma

    In our recent study, we developed a new radiopharmaceutical (rhenium-188 (Re-188) MN-16ET lipiodol) with encouraging results for the treatment of liver malignancy. In this study, we further evaluated the therapeutic efficacy of this radiopharmaceutical by measuring tumor response and survival times in rats with liver tumors after intra-hepatic arterial injection of Re-188 MN-16ET lipiodol. Twelve male rats bearing hepatic tumors were divided into three groups. Group 1 received an intra-hepatic arterial injection of 18.5 MBq Re-188 MN-16ET lipiodol; Group 2 received lipiodol and Group 3 received normal saline. Tumor size was measured by liver sonography before injection, at 2, 4, and 8 weeks after injection. Survival time and response rate were calculated. All rats showed good response and survived over 60 days in Group 1 while all rats showed poor response in Group 2 and Group 3 with only 25% of rats in Group 2 and none (0%) in Group 3 survived over 60 days. The p value was 0.0067 between Group 1 and Group 3; 0.04 between Group 1 and Group 2; and 0.034 between Group 2 and Group 3. Re-188 MN-16ET lipiodol has good potential for the treatment of hepatoma. (author)

  18. Facile Synthesis of Histidine Derivatives for fac-[M(CO)3]+ precursor [M=99mTc, 188Re

    The technetium-99m(99mTc) is one of the most widely used radionuclides in nuclear medicine, because of its preferable properties(T1/2= 6.02 hr, Eγ= 140 keV). More than 85% of diagnostic scans were performed in hospitals worldwide. A variety of 99mTc-based radiopharmaceuticals have been developed for evaluating organ function and assessing disease status by imaging methods. The labeling of biologically active molecules with 99mTc is the most important research area. Although 99mTc complexes with a +5-oxidation state are commonly available recently, many researches have been focused on the 99mTc precursor with the +1-oxidation state [M(CO)3]+ due to its small size and ease in preparation. A variety of researches have revealed that histidine complexes with the fac-[M(CO)3] precursor show a good stability through in-vivo and in-vitro studies. In this study, we present a synthetic approach for the histidine derivatives as bifunctional chelating agent for the conjugation with biomolecules as well as for a labeling with the fac-[M(CO)3]+ precursor [M=99mTc, 186/188Re

  19. Development of Radiopharmaceuticals Based on 188Re and 90Y for Radionuclide Therapy at BARC. Chapter 6

    During the last decade, the group at Bhabha Atomic Research Centre (BARC), India, has focused attention on the development of 90Y based radiopharmaceuticals for therapy. Because the 90Sr/90Y generator is the primary source of high specific activity 90Y, local availability of the generator is crucial in the successful development of 90Y radiopharmaceuticals. In this context, 90Sr/90Y generators based on SLM and electrochemical techniques were designed and deployed at BARC for the elution of 90Y to be used for preparation of 90Y labelled products. This work formed a part of the IAEA CRP entitled Development of Generator Technologies for Therapeutic Radionuclides: 90Y and 188Re. In this chapter, work on the development of 90Y labelled products for treatment of NHL and liver cancer is reported. In addition, validation of the EPC technique for determination of 90Sr contamination in 90Y eluates and its comparison with the United States Pharmacopeia recommended method is presented. (author)

  20. Radiosynovectomy of Painful Synovitis of Knee Joints Due to Rheumatoid Arthritis by Intra-Articular Administration of 177Lu-Labeled Hydroxyapatite Particulates: First Human Study and Initial Indian Experience

    Shinto, Ajit S.; Kamaleshwaran, K. K.; Chakraborty, Sudipta; Vyshakh, K.; Thirumalaisamy, S. G.; Karthik, S.; Nagaprabhu, V. N.; Vimalnath, K. V.; Das, Tapas; Banerjee, Sharmila

    2015-01-01

    The aim of this study is to assess the effectiveness of Radiosynovectomy (RSV) using 177Lu-labeled hydroxyapatite (177Lu-HA) in the treatment of painful synovitis and recurrent joint effusion of knee joints in rheumatoid arthritis (RA). Ten patients, diagnosed with RA and suffering from chronic painful resistant synovitis of the knee joints were referred for RSV. The joints were treated with 333 ± 46 MBq of 177Lu-HA particles administered intra-articularly. Monitoring of activity distribution was performed by static imaging of knee joint and whole-body gamma imaging. The patients were evaluated clinically before RSV and at 6 months after the treatment by considering the pain improvement from baseline values in terms of a 100-point visual analog scale (VAS), the improvement of knee flexibility and the pain remission during the night. RSV response was classified as poor (VAS organs was visible in the whole-body scan. Static scans of the joint at 1 month revealed complete retention of 177Lu-HA in the joints. All patients showed decreased joint swelling and pains, resulting in increased joint motion after 6 months. The percentage of VAS improvement from baseline values was 79.5 ± 20.0% 6 months after RS and found to be significantly related to patients' age (P = 0.01) and duration of the disease (P = 0.03). Knees with Steinbrocker's Grades 0 and I responded better than those with more advanced changes (Steinbrocker's Grades III and IV) in terms of VAS improvement (75% vs. 45.8%) (P < 0.001). The overall success rate (VAS ≥ 50) was 80%. Remission of pain during the night was achieved in 100%, and knee flexibility was improved in 80%. The changes in the blood pool phase before RSV were 3.2 ± 0.7 and after the therapy 1.4 ± 0.7 (P < 0.001). The J/B ratio was: Before RSV 2.4 ± 0.3; after treatment 1.0 ± 0.2 (P < 0.05). CRP concentration 4 and 24 weeks after the therapy was significantly lower than before treatment. The fibrinogen level was not different before and

  1. A comparative study of 51Cr releasing assay and lymphocyte colony inhibition test for detecting LAK activity

    51Cr releasing assay is widely used for detecting cytotoxicity. The correlation coefficient between 51Cr and traditional cyto-colony inhibition test is 0.9915(p51Cr releasing assay is considered to be much simpler and quicker, also can be recommended to be used in clinical practice

  2. Pre-therapeutic dosimetry of normal organs and tissues of {sup 177}Lu-PSMA-617 prostate-specific membrane antigen (PSMA) inhibitor in patients with castration-resistant prostate cancer

    Kabasakal, Levent; AbuQbeitah, Mohammad; Ayguen, Aslan; Yeyin, Nami [Istanbul University, Department of Nuclear Medicine, Cerrahpasa Medical Faculty, Istanbul (Turkey); Ocak, Meltem [Istanbul University, Department of Pharmaceutical Technology, Pharmacy Faculty, Istanbul (Turkey); Demirci, Emre [Sisli Etfal Training and Research Hospital, Department of Nuclear Medicine, Istanbul (Turkey); Toklu, Turkay [Yeditepe University Medical Faculty, Department of Nuclear Medicine, Istanbul (Turkey)

    2015-12-15

    {sup 177}Lu-617-prostate-specific membrane antigen (PSMA) ligand seems to be a promising tracer for radionuclide therapy of progressive prostate cancer. However, there are no published data regarding the radiation dose given to the normal tissues. The aim of the present study was to estimate the pretreatment radiation doses in patients who will undergo radiometabolic therapy using a tracer amount of {sup 177}Lu-labeled PSMA ligand. The study included seven patients with progressive prostate cancer with a mean age of 63.9 ± 3.9 years. All patients had prior PSMA positron emission tomography (PET) imaging and had intense tracer uptake at the lesions. The injected {sup 177}Lu-PSMA-617 activity ranged from 185 to 210 MBq with a mean of 192.6 ± 11.0 MBq. To evaluate bone marrow absorbed dose 2-cc blood samples were withdrawn in short variable times (3, 15, 30, 60, and 180 min and 24, 48, and 120 h) after injection. Whole-body images were obtained at 4, 24, 48, and 120 h post-injection (p.i.). The geometric mean of anterior and posterior counts was determined through region of interest (ROI) analysis. Attenuation correction was applied using PSMA PET/CT images. The OLINDA/EXM dosimetry program was used for curve fitting, residence time calculation, and absorbed dose calculations. The calculated radiation-absorbed doses for each organ showed substantial variation. The highest radiation estimated doses were calculated for parotid glands and kidneys. Calculated radiation-absorbed doses per megabecquerel were 1.17 ± 0.31 mGy for parotid glands and 0.88 ± 0.40 mGy for kidneys. The radiation dose given to the bone marrow was significantly lower than those of kidney and parotid glands (p < 0.05). The calculated radiation dose to bone marrow was 0.03 ± 0.01 mGy/MBq. Our first results suggested that {sup 177}Lu-PSMA-617 therapy seems to be a safe method. The dose-limiting organ seems to be the parotid glands rather than kidneys and bone marrow. The lesion radiation doses are

  3. Pre-therapeutic dosimetry of normal organs and tissues of 177Lu-PSMA-617 prostate-specific membrane antigen (PSMA) inhibitor in patients with castration-resistant prostate cancer

    177Lu-617-prostate-specific membrane antigen (PSMA) ligand seems to be a promising tracer for radionuclide therapy of progressive prostate cancer. However, there are no published data regarding the radiation dose given to the normal tissues. The aim of the present study was to estimate the pretreatment radiation doses in patients who will undergo radiometabolic therapy using a tracer amount of 177Lu-labeled PSMA ligand. The study included seven patients with progressive prostate cancer with a mean age of 63.9 ± 3.9 years. All patients had prior PSMA positron emission tomography (PET) imaging and had intense tracer uptake at the lesions. The injected 177Lu-PSMA-617 activity ranged from 185 to 210 MBq with a mean of 192.6 ± 11.0 MBq. To evaluate bone marrow absorbed dose 2-cc blood samples were withdrawn in short variable times (3, 15, 30, 60, and 180 min and 24, 48, and 120 h) after injection. Whole-body images were obtained at 4, 24, 48, and 120 h post-injection (p.i.). The geometric mean of anterior and posterior counts was determined through region of interest (ROI) analysis. Attenuation correction was applied using PSMA PET/CT images. The OLINDA/EXM dosimetry program was used for curve fitting, residence time calculation, and absorbed dose calculations. The calculated radiation-absorbed doses for each organ showed substantial variation. The highest radiation estimated doses were calculated for parotid glands and kidneys. Calculated radiation-absorbed doses per megabecquerel were 1.17 ± 0.31 mGy for parotid glands and 0.88 ± 0.40 mGy for kidneys. The radiation dose given to the bone marrow was significantly lower than those of kidney and parotid glands (p < 0.05). The calculated radiation dose to bone marrow was 0.03 ± 0.01 mGy/MBq. Our first results suggested that 177Lu-PSMA-617 therapy seems to be a safe method. The dose-limiting organ seems to be the parotid glands rather than kidneys and bone marrow. The lesion radiation doses are within acceptable

  4. Clinical results of radionuclide therapy of neuroendocrine tumours with {sup 90}Y-DOTATATE and tandem {sup 90}Y/{sup 177}Lu-DOTATATE: which is a better therapy option?

    Kunikowska, Jolanta; Krolicki, Leszek [Medical University of Warsaw, Nuclear Medicine Department, Warsaw (Poland); Hubalewska-Dydejczyk, Alicja; Sowa-Staszczak, Anna [Collegium Medicum Cracow, Cracow (Poland); Mikolajczak, Renata; Pawlak, Dariusz [Institute of Atomic Energy POLATOM, Swierk-Otwock (Poland)

    2011-10-15

    Peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues is a treatment option for patients with disseminated neuroendocrine tumours (NET). A combination treatment using the high-energy {sup 90}Y beta emitter for larger lesions and the lower energy {sup 177}Lu for smaller lesions has been postulated in the literature.The aim of the study was to evaluate combined {sup 90}Y/{sup 177}Lu-DOTATATE therapy in comparison to {sup 90}Y-DOTATATE alone. Fifty patients with disseminated NET were included in the study prospectively and divided into two groups: group A (n = 25) was treated with {sup 90}Y-DOTATATE, whereas group B (n = 25) received the 1:1 {sup 90}Y/{sup 177}Lu-DOTATATE. The administered activity was based on 3.7 GBq/m{sup 2} body surface area in three to five cycles, with amino acid infusion for nephroprotection. The median overall survival time in group A was 26.2 months while in group B median survival was not reached. Overall survival was significantly higher in group B (p = 0.027). Median event-free survival time in group A was 21.4 months and in group B 29.4 months (p > 0.1). At the 12-month follow-up, comparison of group A vs group B showed stable disease (SD) in 13 vs 16 patients, disease regression (RD) in 5 vs 3 patients and disease progression (PD) in 3 vs 4 patients; 4 and 2 patients died, respectively. The 24-month follow-up results were SD in nine vs ten patients, RD in one patient vs none and PD in four patients in both groups; three and four patients died, respectively. Side effects were rare and mild. The results indicate that therapy with tandem radioisotopes ({sup 90}Y/{sup 177}Lu-DOTATATE) provides longer overall survival than with a single radioisotope ({sup 90}Y-DOTATATE) and the safety of both methods is comparable. (orig.)

  5. Peptide receptor radionuclide therapy with {sup 177}Lu-DOTATATE in advanced bronchial carcinoids: prognostic role of thyroid transcription factor 1 and {sup 18}F-FDG PET

    Ianniello, Annarita; Sansovini, Maddalena; Severi, Stefano; Nicolini, Silvia; Caroli, Paola; Paganelli, Giovanni [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Nuclear Medicine and Radiometabolic Unit, Meldola (Italy); Grana, Chiara Maria [European Institute of Oncology Milan (IEO), Division of Nuclear Medicine, Milan (Italy); Massri, Katrin [Ospedale San Luca, Nuclear Medicine, Department of Radiology, Lucca (Italy); Bongiovanni, Alberto [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Osteoncology and Rare Tumors Center, Meldola (Italy); Antonuzzo, Lorenzo [AOU Careggi, SC Oncologia Medica 1, Firenze (Italy); Di Iorio, Valentina [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Oncology Pharmacy Laboratory, Meldola (Italy); Sarnelli, Anna [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Medical Physics Unit, Meldola (Italy); Monti, Manuela; Scarpi, Emanuela [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Unit of Biostatistics and Clinical Trials, Meldola (Italy)

    2016-06-15

    Typical and atypical carcinoids (TC and AC) represent 20 - 25 % of all neuroendocrine tumours. No standard therapeutic approach is available for patients with advanced disease. The aim of this phase II study was to investigate the efficacy and safety of peptide receptor radionuclide therapy with {sup 177}Lu-DOTATATE (Lu-PRRT) and the role of thyroid transcription factor 1 (TTF-1) and {sup 18}F-FDG PET as prognostic factors in patients with advanced TC or AC. A total of 34 consecutive patients with radiologically documented progressive disease were treated with Lu-PRRT at a therapeutic cumulative activity of 18.5 or 27.8 GBq in four or five cycles according to the patient's kidney function and bone marrow reserve. Information on TTF-1 was available in all patients. FDG PET studies prior to Lu-PRRT were available in 29 patients. The median follow-up was 29 months (range 7 - 69 months). The disease control rate (DCR) in patients with TC was 80 %: 6 % complete response, 27 % partial response and 47 % stable disease. The median progression-free survival (mPFS) was 20.1 months (95 % CI 11.8 - 26.8 months). Stable disease was achieved in 47 % of patients with AC with a mPFS of 15.7 months (95 % CI 10.6 - 25.9 months). No major acute or delayed toxicity occurred in either group or with either cumulative activity. mPFS in patients with TTF-1-negative TC was 26.3 months (95 % CI 12.9 - 45.2 months), but in patients with TTF-1-positive TC mPFS was 7.2 months (4.2 - 14.0 months; p = 0.0009). FDG PET was negative in 13 patients (10 TC and 3 AC) and positive in 16 patients (4 TC and 12 AC). The mPFS in the FDG PET-negative group was 26.4 months (95 % CI 14.2 - 48.9 months) and 15.3 months (11.7 - 31.1 months) in the FDG PET-positive group. Lu-PRRT showed antitumour activity in terms of DCR and PFS and proved safe, even in patients with a higher risk of side effects. TTF-1 would appear to be a prognostic factor. FDG PET positivity in bronchial carcinoids is a hallmark of

  6. Peptide receptor radionuclide therapy with {sup 90}Y/{sup 177}Lu-labelled peptides for inoperable head and neck paragangliomas (glomus tumours)

    Puranik, Ameya D.; Kulkarni, Harshad R.; Singh, Aviral; Baum, Richard P. [Zentralklinik Bad Berka, THERANOSTICS Centre for Molecular Radiotherapy and Molecular Imaging, ENETS Center of Excellence, Bad Berka (Germany)

    2015-07-15

    Head and neck paragangliomas (HNPGLs) are rare tumours arising from autonomic nervous system ganglia. Although surgery offers the best chance of complete cure, there is associated morbidity due to the crucial location of these tumours. Radiotherapy arrests tumour growth and provides symptomatic improvement, but has long-term consequences. These tumours express somatostatin receptors (SSTR) and hence peptide receptor radionuclide therapy (PRRT) is now a treatment option. We assessed the molecular, morphological and clinical responses of inoperable HNPGLs to PRRT. Nine patients with inoperable HNPGL assessed between June 2006 and June 2014 were included. Four patients had a solitary lesion, four had multifocal involvement and one had distant metastases (bone and lungs). The patients were treated with PRRT using {sup 90}Y/{sup 177}Lu-labelled peptides after positive confirmation of SSTR expression on {sup 68}Ga-DOTATOC PET/CT. All patients received two to four courses of PRRT. Subsequent serial imaging with {sup 68}Ga-DOTATOC PET/CT was carried out every 6 months to assess response to treatment. Clinical (symptomatic) response was also assessed. Based on molecular response (EORTC) criteria, four of the nine patients showed a partial molecular response to treatment seen as significant decreases in SUV{sub max}, accompanied by a reduction in tumour size. Five patients showed stable disease on both molecular and morphological criteria. Six out of nine patients were symptomatic at presentation with manifestations of cranial nerve involvement, bone destruction at the primary site and metastatic bone pain. Molecular responses were correlated with symptomatic improvement in four out of these six patients; while two patients showed small reductions in tumour size and SUV{sub max}. The three asymptomatic patients showed no new lesions or symptomatic worsening. PRRT was effective in all patients, with no disease worsening seen, either in the form of neurological symptoms or

  7. Role of {sup 18}FDG PET/CT in patients treated with {sup 177}Lu-DOTATATE for advanced differentiated neuroendocrine tumours

    Severi, Stefano; Sansovini, Maddalena; Ianniello, Annarita; Matteucci, Federica [Cancer Institute of Romagna (IRST), Unit of Radiometabolic Medicine, Meldola, FC (Italy); Nanni, Oriana; Scarpi, Emanuela [Cancer Institute of Romagna (IRST), Unit of Biostatistics and Clinical Trials, Meldola, FC (Italy); Bodei, Lisa; Gilardi, Laura; Paganelli, Giovanni [European Institute of Oncology, Division of Nuclear Medicine, Milan (Italy); Nicoletti, Stefania [Cancer Institute of Romagna (IRST), Unit of Medical Oncology, Meldola, FC (Italy)

    2013-06-15

    The prognostic value of FDG PET for neuroendocrine tumours (NETs) has been reported. In this study we evaluated the role of FDG PET in predicting response and progression-free survival (PFS) after {sup 177}Lu-DOTATATE peptide receptor radionuclide therapy (Lu-PRRT) in patients with advanced well-differentiated grade 1/2 NETs. We retrospectively evaluated 52 patients with progressive advanced NETs overexpressing somatostatin receptors and treated with Lu-PRRT with a cumulative activity up to 27.7 GBq divided into five courses. According to WHO 2010/ENETS classification, patients were stratified into two groups: those with grade 1 tumour (Ki-67 index {<=}2 %, 19 patients), and those with grade 2 tumour (Ki-67 index >3 % to <20 %, 33 patients). On the basis of the FDG PET scan, 33 patients were classified as PET-positive (PET+) and 19 as PET-negative (PET-). FDG PET was positive in 57 % of patients with grade 1 NET and in 66 % of patients with grade 2 NET, and the rates of disease control (DC, i.e. complete response + partial response + stable disease) in grade 1 and grade 2 patients were 95 % and 79 %, respectively (P = 0.232). In PET- and PET+ patients, the DC rates were 100 % and 76 % (P = 0.020) with a PFS of 32 and 20 months, respectively (P = 0.033). Of the PET+ patients with grade 1 NET, 91 % showed disease control, whereas about one in three PET+ patients with grade 2 NET (32 %) progressed after Lu-PRRT (DC rate 68 %). These results suggest that FDG PET evaluation is useful for predicting response to Lu-PRRT in patients with grade 1/2 advanced NETs. Notably, none of PET- patients had progressed at the first follow-up examination after Lu-PRRT. Grade 2 NET and PET+ (arbitrary SUV cutoff >2.5) were frequently associated with more aggressive disease. PET+ patients with grade 2 NET, 32 % of whom did not respond to Lu-PRRT monotherapy, might benefit from more intensive therapy protocols, such as the combination of chemotherapy and PRRT. (orig.)

  8. Country report: Cuba. Local Production of 90Y And 188Re Radionuclides and Development of Radiopharmaceuticals for Therapy

    During the first period of this CRP we could test an efficient and reliable generator system based on ion-chromatography to obtain 90Y from its parent radionuclide 90Sr. This production scheme for 90Y was outlined in the previous CRP related with the development of generator technologies. Quality parameters such as trace metals that can potentially interfere in the labeling of biomoléculas, 90Y recovery, 90Sr/90Y ratio and radiation dose to bed matrix were evaluated. The results showed that high recovery and radionuclidic purity could be obtained for 90Y during its repeated separation from the 90Sr cow. No replacement or treatment of the cow were necessary and low waste generation and 90Sr losses less that 0.1% after each run were also observed during the present study. A Fab’ fragment was enzimatically produced and purified from the monoclonal antibody h-R3 (Nimotuzumab®). The fragment and the parent antibody were successfully conjugated with DOTA and labeled with 90Y. The radioinmunoconjugate thus obtained also exhibited a good 24 h in-vitro stability in an excess of DTPA. A 90Y radiocoloid was prepared in a cromic phosphate particle for radiosynoviorthesis with promising results in animal models. Two alumina based 188W/188Re generators were prepared and their eluates were used in the labeling of hR3-DOTA conjugates. Quality control and in vivo evaluation in comparison with 99mTc-hR3 showed very good results and similar pattern of distribution and pharmacokinetic and will be used in clinical trials for cancer patients. (author)

  9. Metastatic Neuroendocrine Tumor with Extensive Bone Marrow Involvement at Diagnosis: Evaluation of Response and Hematological Toxicity Profile of PRRT with (177)Lu-DOTATATE.

    Basu, Sandip; Ranade, Rohit; Thapa, Pradeep

    2016-01-01

    The aim of this study was to evaluate the response and hematological toxicity in peptide receptor radionuclide therapy (PRRT) with lutetium ((177)Lu)-DOTA-octreotate (DOTATATE) in metastatic neuroendocrine tumor (NET) with extensive bone marrow metastasis at the initial diagnosis. A retrospective evaluation was undertaken for this purpose: Patients with NET with extensive diffuse bone marrow involvement at diagnosis who had received at least three cycles of PRRT with (177)Lu-DOTATATE were considered for the analysis. The selected patients were analyzed for the following: (i) Patient and lesional characteristics, (ii) associated metastatic burden, (iii) hematological parameters at diagnosis and during the course of therapy, (iv) response to PRRT (using a 3-parameter assessment: Symptomatic including Karnofsky/Lansky performance score, biochemical finding, and scan finding), (v) dual tracer imaging features [with somatostatin receptor imaging (SRI) and fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT)]. Based on the visual grading, tracer uptake in somatostatin receptor (SSTR)-positive bone marrow lesions were graded by a 4-point scale into four categories (0-III) in comparison with the hepatic uptake on the scan: 0 - no uptake; I - clear focus but less than liver uptake; II - equal to liver uptake; and III - higher than liver uptake]. Hematological toxicity was evaluated using National Cancer Institute (NCI)-Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 score. A total of five patients (age range: 26-62 years; three males and two females) with diffuse bone marrow involvement at the diagnosis was encountered following analysis of the entire patient population of 250 patients. Based on the site of the primary, three had thoracic NET (two patients bronchial carcinoid and one pulmonary NET) and two gastroenteropancreatic NET (one in the duodenum and one patient of unknown primary with liver metastasis). Associated sites

  10. Metastatic Neuroendocrine Tumor with Extensive Bone Marrow Involvement at Diagnosis: Evaluation of Response and Hematological Toxicity Profile of PRRT with 177Lu-DOTATATE

    Basu, Sandip; Ranade, Rohit; Thapa, Pradeep

    2016-01-01

    The aim of this study was to evaluate the response and hematological toxicity in peptide receptor radionuclide therapy (PRRT) with lutetium (177Lu)-DOTA-octreotate (DOTATATE) in metastatic neuroendocrine tumor (NET) with extensive bone marrow metastasis at the initial diagnosis. A retrospective evaluation was undertaken for this purpose: Patients with NET with extensive diffuse bone marrow involvement at diagnosis who had received at least three cycles of PRRT with 177Lu-DOTATATE were considered for the analysis. The selected patients were analyzed for the following: (i) Patient and lesional characteristics, (ii) associated metastatic burden, (iii) hematological parameters at diagnosis and during the course of therapy, (iv) response to PRRT (using a 3-parameter assessment: Symptomatic including Karnofsky/Lansky performance score, biochemical finding, and scan finding), (v) dual tracer imaging features [with somatostatin receptor imaging (SRI) and fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT)]. Based on the visual grading, tracer uptake in somatostatin receptor (SSTR)-positive bone marrow lesions were graded by a 4-point scale into four categories (0-III) in comparison with the hepatic uptake on the scan: 0 - no uptake; I - clear focus but less than liver uptake; II - equal to liver uptake; and III - higher than liver uptake]. Hematological toxicity was evaluated using National Cancer Institute (NCI)-Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 score. A total of five patients (age range: 26-62 years; three males and two females) with diffuse bone marrow involvement at the diagnosis was encountered following analysis of the entire patient population of 250 patients. Based on the site of the primary, three had thoracic NET (two patients bronchial carcinoid and one pulmonary NET) and two gastroenteropancreatic NET (one in the duodenum and one patient of unknown primary with liver metastasis). Associated sites of

  11. Country report: United Kingdom. Bifunctional bisphosphonate complexes with 99mTc and 188Re for the diagnosis and therapy of bone metastases

    1,1-Bisphosphonates (BPs) are a family of compounds extensively used in the management of disorders of bone metabolism.1 They accumulate in areas of high bone metabolism, such as bone metastases, and consequently have been receiving increasing attention as molecular imaging probes and pain palliation treatments.2 Imaging bone metastases with BPs using single photon emission computed tomography (SPECT) or planar scintigraphy is one of the most often-performed clinical imaging procedures. Beta-emitting analogues capable of producing a therapeutic effect have also been developed.3 In particular, the rhenium compounds 186/188Re-hydroxyethylidene-1,1-diphosphonate (186/188Re-HEDP) have shown promise as palliative agents for bone metastases in recent clinical trials.4 The radiochemicals consist of a complex of a BP (e.g. methylene diphosphonate, MDP) with gamma- (99mTc) or beta- (186/186Re) emitters

  12. Dosimetry and microdosimetry of 188 Re-anti-CD20 and 131 I-anti-CD20 for the treatment of No Hodgkin lymphomas

    The purpose of this investigation was to prepare 131I-anti-CD20 and 188Re-anti-CD20 and to estimate the radiation absorbed dose at macro- and micro- level during a NHL treatment. The work was divided in 4 general objectives: 1) preparation of 131I-anti-CD20 and 188Re-anti-CD20, 2) application in patients to obtain biokinetic parameters and estimate the organ absorbed doses 3) estimation of the cellular dosimetry using the MIRD methodology and the MCNP4C2 code and 4) estimation of the cellular microdosimetry using the NOREC code. 188Re-anti-CD20 was prepared by a direct labelling method using sodium tartrate as a weak ligand. To evaluate the biological recognition a comparative study of the in vitro binding of 188Re-anti-CD20, 125I-anti-CD20 (positive control) and 188Re-anti-CEA (negative control) to normal B Iymphocytes was performed. Biodistribution studies in normal mice were accomplished to assess the in vivo Re-anti-CD20 complex stability. The binding of ' Re-anti-CD20 to cells was in the same range as '251-anti-CD20 (>80%) considered as the positive control. 188Re-anti-CD20 and '3'1-anti-CD20 prepared were administered in patients diagnosed with B cell NHL at the Centro Medico Siglo XXI (IMSS). The protocol was approved by the hospital's Medical Ethics Committee. AJI patients signed a consent form after receiving detailed information on the aims of the study. N data were the input for the OLINDA/EXM software to calculate the radiation absorbed dose to organs and whole body. Dosimetric studies indicate that after administration of 6.4 GBq and 4.87 to 8.75 GBq of '3'1-anti-CD20 and 188Re-anti-CD20 respectively, the absorbed dose to total body would be 0.75 Gy which corresponds to the recommended dose for NHL therapies. The calculated organ absorbed doses indicate that 188Re-anti-CD20 may be used in radioimmunotherapy without the risk of toxicity to red marrow or healthy organs. The absorbed dose (D) into cellular nucleus was calculated by two different

  13. Therapeutic effect of intratumoral injection of 188Re labeled stannic sulfur suspension in liver cancer. A comparative study with chemical agents in nude mice

    Objectives: Hepatoma is a common disease in some countries. The intervention therapy was used often for non-resectable tumor. The aim of our study was to compare the therapeutic effect of 188Re labeled stannic sulfur suspension to ethanol, acetic acid and the mixture of mitomycin and lipiodol for hepatoma in an animal model by intermittently injection. Methods: Forty-nine nude mice bearing hepatic cell carcinoma were divided into six groups. Group 1 (n=14) was intratumoral y injected with 0.1 ml saline. There were 5 experimental groups (group 2 to 6). Each group consisted of 7 mice. The mice in group 2 was intratumoral y injected with 18.5 MBq/0.1 ml 188Re labeled stannic sulfur suspension each, the mice in group 3 was injected intratumorally with 9.25 MBq/0.1 ml 188Re labeled stannic sulfur suspension each, group 4 was injected intratumorally with 0.1 ml ethanol, the mice in group 5 was injected with 0.1 ml 30% acetic acid and group 6 was injected intratumorally with 30 μg mitomycin in 0.1 ml lipiodol respectively. The mice were sacrificed 7 days post injection and the specimen were collected for pathological analysis. Results: The average tumor weight were 1.75±0.29 g (mean±S.D.), 0.26±0.03 g, 0.44±0.17 g, 1.38±0.25 g, 0.91±0.28 g, 1.38±0.28 g for group 1 to 6 respectively. Tumors in all experimental groups were significantly smaller than group 1 (control group, P88Re labeled stannic sulfur suspension injection had the smallest tumor weight among all the experimental groups (P188Re labeled stannic sulfur suspension shows better therapeutic effect. (authors)

  14. Development of pharmaceuticals with radioactive rhenium for cancer therapy. Production of {sup 186}Re and {sup 188}Re, synthesis of labeled compounds and their biodistributions

    NONE

    1998-03-01

    Production of the radioactive rhenium isotopes {sup 186}Re and {sup 188}Re, and synthesis of their labeled compounds have been studied together with the biodistributions of the compounds. This work was carried out by the Working Group on Radioactive Rhenium, consisting of researchers of JAERI and some universities, in the Subcommittee for Production and Radiolabeling under the Consultative Committee of Research on Radioisotopes. For {sup 186}Re, production methods by the {sup 185}Re(n,{gamma}){sup 186}Re reaction in a reactor and by the {sup 186}W(p,n){sup 186}Re reaction with an accelerator, which can produce nocarrier-added {sup 186}Re, have been established. For {sup 188}Re, a production method by the double neutron capture reaction of {sup 186}W, which produces a {sup 188}W/{sup 188}Re generator, has been established. For labeling of bisphosphonate, DMSA, DTPA, DADS, aminomethylenephosphonate and some monoclonal antibodies with the radioactive rhenium isotopes, the optimum conditions, including pH, the amounts of reagents and so on, have been determined for each compound. The biodistributions of each of the labeled compounds in mice have been also obtained. (author)

  15. Isostructural folate conjugates radiolabeled with the matched pair 99mTc/188Re: a potential strategy for diagnosis and therapy of folate receptor-positive tumors

    99mTc-technetium (99mTc) and 188Re-rhenium (188Re) represent an interesting pair of radionuclides for diagnosis and therapy. The aim of this study was to synthesize and characterize in vitro/in vivo the first 188Re-folate derivative [188Re(CO)3-picolylamine monoacetic acid 188Re-PAMA-folate (2)] for potential targeted radionuclide therapy of FR-positive tumors. The data were compared with those of the isostructural 99mTc-analog [99mTc-PAMA folate (1)] reported previously. Methods: In vitro stability of compound was tested in phosphate-buffered saline and human plasma. Cell binding experiments were performed with FR-positive human KB cells. Biodistribution was assessed in female nude mice, bearing KB tumor xenografts. Results: Cell binding experiments showed high and FR-specific uptake. In vivo, compound accumulated specifically in the FR-positive tumors with maximal values 4 h post injection (p.i.) [: 1.87±0.04 percent injected dose per gram of weight tissue (% ID/g) vs. : 2.33±0.36% ID/g]. Unfavorably high retention of radioactivity was found in FR-positive kidneys (12.04±0.62% ID/g; 4 h p.i.). Tumor-to-blood ratio of radioactivity (: 14.5±1.32, 4 h p.i.) was lower than for compound (58.0±12.2, 4 h p.i.), whereas tumor-to-kidney ratios were in the same range (: 0.15±0.01 vs. : 0.13±0.02, 4 h p.i.). Preadministration of the antifolate pemetrexed significantly improved the tumor-to-kidney ratio (: 1.59±0.30, 4 h p.i.). Conclusions: The isostructural radiofolates and displayed almost identical pharmacokinetic profiles and accumulated both specifically in FR-positive tumors. However, only the coapplication of the antifolate pemetrexed improved the biodistribution of the radiotracers in such ways that a potential therapeutic application of compound can be envisaged in the future

  16. 51Cr-EDTA plasma clearance in severe renal failure determined by one plasma sample

    Kamper, A L; Nielsen, S L

    1989-01-01

    sample clearance' formulas disregarding exact time of plasma sampling. This method might provide values 3.1 ml/min below or 2.9 ml/min above the established method of total 51Cr-EDTA plasma clearance, and would thus provide insufficient agreement. In the other method an estimate of plasma activity at......Two hundred and thirty-four measurements of standard 51Cr-EDTA plasma clearance were made in 50 patients with severe chronic renal failure. Based on these data two calculation methods were attempted using one plasma sample drawn 24 h after injection of 51Cr-EDTA. One of the methods used the 'one...... zero-time was derived from injected dose and body surface area. This method might provide values 1.5 ml/min below or 0.8 ml/min above the established method of 51Cr-EDTA plasma clearance, which would be acceptable for clinical purposes. It is concluded that exact plasma clearance of 51Cr-EDTA in severe...

  17. (51Cr)EDTA intestinal permeability in children with cow's milk intolerance

    Schrander, J.J.; Unsalan-Hooyen, R.W.; Forget, P.P.; Jansen, J. (Academic Hospital Maastricht (Netherlands))

    1990-02-01

    Making use of ({sup 51}Cr)EDTA as a permeability marker, we measured intestinal permeability in a group of 20 children with proven cow's milk intolerance (CMI), a group of 17 children with similar complaints where CMI was excluded (sick controls), and a group of 12 control children. ({sup 51}Cr)EDTA test results (mean +/- SD) were 6.85 +/- 3.64%, 3.42 +/- 0.94%, and 2.61 +/- 0.67% in the group with CMI, the sick control, and the control group, respectively. When compared to both control groups, patients with cow's milk intolerance (CMI) showed a significantly increased small bowel permeability. We conclude that the ({sup 51}Cr)EDTA test can be helpful for the diagnosis of cow's milk intolerance.

  18. [51Cr]EDTA intestinal permeability in children with cow's milk intolerance

    Making use of [51Cr]EDTA as a permeability marker, we measured intestinal permeability in a group of 20 children with proven cow's milk intolerance (CMI), a group of 17 children with similar complaints where CMI was excluded (sick controls), and a group of 12 control children. [51Cr]EDTA test results (mean +/- SD) were 6.85 +/- 3.64%, 3.42 +/- 0.94%, and 2.61 +/- 0.67% in the group with CMI, the sick control, and the control group, respectively. When compared to both control groups, patients with cow's milk intolerance (CMI) showed a significantly increased small bowel permeability. We conclude that the [51Cr]EDTA test can be helpful for the diagnosis of cow's milk intolerance

  19. Evaluation of 177Lu-DOTA-labeled aglycosylated monoclonal anti-L1-CAM antibody chCE7: influence of the number of chelators on the in vitro and in vivo properties

    Introduction: In this study, we optimized the 1,4,7,10-tetraazacyclododecane-N-N'-N''-N''''-tetraacetic acid (DOTA) chelator-to-antibody (c/a) ratio for the aglycosylated variant of the anti-L1-CAM antibody chCE7 (chCE7agl), providing high specific activity and low liver uptake in 177Lu-labeled form. Methods: chCE7agl was substituted with increasing molar excess of DOTA-NCS. The number of chelators coupled to the antibody and the binding affinities to target tumor cells (IC5 values) of the resulting immunoconjugates were determined. The different immunoconjugates were labeled with 177Lu; specific activity was measured, and metabolic stability was analyzed in human plasma. The effect of different c/a ratios on blood clearance and liver uptake was tested in nude mice. Changes of the protein backbone structure were analyzed by circular dichroism spectroscopy. Results: chCE7agl was substituted with 7, 12 or 15 DOTA ligands. The IC5 concentrations displacing radioiodinated chCE7 antibody increased with the number of chelators (1.5-fold with 7 ligands, 2.5-fold with 12 ligands and a 5-fold increase with 15 ligands). The highest specific activity for 177Lu-DOTA-chCE7agl was obtained with a c/a ratio of 12 (106 MBq/mg). Radioimmunoconjugates were stable in human plasma for at least 24 h. Blood clearance and liver uptake were measured after 24 h (c/a ratios of 12 and 15) or 48 h (c/a ratio of 7). The liver-to-blood ratios were 0.35±0.14 (7 ligands), 0.77±0.19 (12 ligands) and 17.85±3.44 (15 ligands). Conclusions: DOTA-chCE7agl conjugates with a c/a ratio of 12 combined high specific activity with good in vitro and in vivo properties. The rapid elimination rate from the blood and the high uptake in the liver of chCE7agl substituted with 15 DOTA ligands were found not to be due to conformational changes of the antibody backbone structure

  20. Synthesis and characterization of {sup 99m}Tc- and {sup 188}Re-complexes with a diamido-dihydroxymethylenephosphine-based bifunctional chelating agent (N{sub 2}P{sub 2}-BFCA)

    Kothari, K.K. E-mail: kanchan@apsara.barc.ernet.in; Gali, H.; Prabhu, K.R.; Pillarsetty, N.; Owen, N.K.; Katti, K.V.; Hoffman, T.J.; Volkert, W.A

    2002-01-01

    A diamido-dihydroxymethylenephosphine (N{sub 2}P{sub 2}) bifunction chelating agent (BFCA) was shown to form well-defined {sup 99m}Tc- and {sup 188}Re-chelate structures. The 4, 4-bis [bis-hydroxymethyl-phosphonyl-propylcarbonmoyl]-butyric acid bifunctional chelating agent (N{sub 2}P{sub 2}-BFCA) formed stable complexes with {sup 99m}Tc and {sup 188}Re in >95% yield with high radiochemical purity (RCP). The biodistribution of the {sup 99m}Tc- and {sup 188}Re-N{sub 2}P{sub 2}-BFCAs after intravenous injection studied in normal mice showed the activity was excreted primarily via renal-urinary pathway indicating their use for labeling peptides with {sup 99m}Tc and {sup 188}Re.

  1. 51Cr-EDTA: a marker of early intestinal rejection in the rat

    Intestinal permeability was studied after accessory intestinal transplantation in Lewis rats. Five groups were evaluated: Group 1--isografts (N = 6); Group 2--Lewis X Brown Norway F1 (LBN-F1) allografts (N = 6); Group 3--isografts treated with CsA 2 mg/kg/day X 10 days (N = 6); Group 4--LBN-F1 allografts treated with CsA 2 mg/kg/day X 10 days (N = 6); Group 5--LBN-F1 allografts treated with CsA 4 mg/kg/day X 28 days (N = 6). Chromium-labeled ethylenedimianetetraacetate (51Cr-EDTA) was given through the proximal stoma of the graft. Renal clearance of 51Cr-EDTA and mucosal biopsies were followed post-transplant. The biopsies of the intestinal graft showed no rejection in Groups 1, 3, and 5; fulminant rejection in Group 2; and mild atypical rejection in Group 4. 51Cr-EDTA clearance was elevated in all groups during the first 7 days post-transplant. Thereafter, 51Cr-EDTA excretion fell to lower levels in the animals with histologically normal grafts (Groups 1, 3, and 5). 51Cr-EDTA excretion in Group 4 was increased with the first histological evidence of rejection on Day 14 and remained elevated until sacrifice (P less than 0.02 compared to Groups 3 and 5). A transient permeability defect occurs after intestinal grafting. Once the graft has recovered from this injury, 51Cr-EDTA is a sensitive marker for intestinal rejection

  2. Study of erythropoiesis with 59Fe and erythrocyte survival with 51Cr in aplastic anemia

    A study of erythropoiesis with 59Fe and erythrocyte survival with 51Cr was carried out in 25 patients with aplastic anemia and in a control group of 23 healthy persons. Bone marrow aplasia was uniform in all patients but differences in erythropoiesis were established. According to the state of erythropoiesis, the patients were divided into two groups: 1) patients with severe damage of erythropoiesis and 2) patients with preserved erythropoiesis. Erythrocyte survival in both groups was shortened. The data obtained correlate with the anemic syndrome and help to explain its pathogenesis. It is suggested that the investigation of erythropoiesis with 59Fe and 51Cr is of prognostic value. (author)

  3. Assessment of mineral dust cytotoxicity toward rat alveolar macrophages using a 51Cr release assay

    An assay was developed to assess the cytotoxicity of mineral dust by measuring release of 51Cr from prelabeled rat alveolar macrophages. Optimal conditions for the assay are described, the most notable being use of 2% albumin instead of fetal calf serum. The assay demonstrated loss of label into the supernatant when prelabeled macrophages were cultured with the two pathogenic mineral dusts, quartz and chrysotile asbestos. In contrast the inert mineral dust titanium dioxide had very little effect on 51Cr release by rat alveolar macrophages

  4. Application of 51Cr in examination of patients with hereditary microspherocytic hemolytic anemia

    A total of 20 patients with hereditary microspherocytic hemolytic anemia were examined by the method of erythrocyte labelling with 51Cr. The survival rate of the erythrocytes appeared to be shortened in all the patients. The degree of this shortening corresponded to the severity of the clinico-hematological signs of hemolysis. The sequestrating capacity of the spleen elevated in all patients increased as the organ enlarged. The efficacy of splenectomy was checked in 11 patients by a repeated control examination with 51Cr. The given test can be successfully used for diagnosis of hemolytic conditions, evaluation of their clinical course severity, prognosis and assessment of splenectomy efficacy

  5. Theranostic pretargeted radioimmunotherapy of colorectal cancer xenografts in mice using picomolar affinity 86Y- or 177Lu-DOTA-Bn binding scFv C825/GPA33 IgG bispecific immunoconjugates

    GPA33 is a colorectal cancer (CRC) antigen with unique retention properties after huA33-mediated tumor targeting. We tested a pretargeted radioimmunotherapy (PRIT) approach for CRC using a tetravalent bispecific antibody with dual specificity for GPA33 tumor antigen and DOTA-Bn-(radiolanthanide metal) complex. PRIT was optimized in vivo by titrating sequential intravenous doses of huA33-C825, the dextran-based clearing agent, and the C825 haptens 177Lu-or 86Y-DOTA-Bn in mice bearing the SW1222 subcutaneous (s.c.) CRC xenograft model. Using optimized PRIT, therapeutic indices (TIs) for tumor radiation-absorbed dose of 73 (tumor/blood) and 12 (tumor/kidney) were achieved. Estimated absorbed doses (cGy/MBq) to tumor, blood, liver, spleen, and kidney for single-cycle PRIT were 65.8, 0.9 (TI 73), 6.3 (TI 10), 6.6 (TI 10), and 5.3 (TI 12), respectively. Two cycles of PRIT (66.6 or 111 MBq 177Lu-DOTA-Bn) were safe and effective, with a complete response of established s.c. tumors (100 - 700 mm3) in nine of nine mice, with two mice alive without recurrence at >140 days. Tumor log kill in this model was estimated to be 2.1 - 3.0 based on time to 500-mm3 tumor recurrence. In addition, PRIT dosimetry/diagnosis was performed by PET imaging of the positron-emitting DOTA hapten 86Y-DOTA-Bn. We have developed anti-GPA33 PRIT as a triple-step theranostic strategy for preclinical detection, dosimetry, and safe targeted radiotherapy of established human colorectal mouse xenografts. (orig.)

  6. Theranostic pretargeted radioimmunotherapy of colorectal cancer xenografts in mice using picomolar affinity {sup 86}Y- or {sup 177}Lu-DOTA-Bn binding scFv C825/GPA33 IgG bispecific immunoconjugates

    Cheal, Sarah M.; Lee, Sang-gyu; Punzalan, Blesida; Larson, Steven M. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Memorial Sloan Kettering Cancer Center, Molecular Pharmacology and Chemistry Program, New York, NY (United States); Xu, Hong; Guo, Hong-fen [Memorial Sloan Kettering Cancer Center, Department of Pediatrics, New York, NY (United States); Chalasani, Sandhya; Carrasquillo, Jorge A. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Fung, Edward K. [Memorial Sloan Kettering Cancer Center, Molecular Pharmacology and Chemistry Program, New York, NY (United States); Memorial Sloan Kettering Cancer Center, Department of Medical Physics, New York, NY (United States); Jungbluth, Achim [Memorial Sloan Kettering Cancer Center, Department of Pathology, New York, NY (United States); Zanzonico, Pat B.; O' Donoghue, Joseph [Memorial Sloan Kettering Cancer Center, Department of Medical Physics, New York, NY (United States); Smith-Jones, Peter M. [Stony Brook University, Department of Psychiatry and Behavioral Science, Stony Brook, NY (United States); Stony Brook University, Department of Radiology, Stony Brook, NY (United States); Wittrup, K.D. [Massachusetts Institute of Technology, Department of Chemical Engineering, Cambridge, MA (United States); Massachusetts Institute of Technology, Department of Biological Engineering, Cambridge, MA (United States); Massachusetts Institute of Technology, Koch Institute for Integrative Cancer Research, Cambridge, MA (United States); Cheung, Nai-Kong V. [Memorial Sloan Kettering Cancer Center, Molecular Pharmacology and Chemistry Program, New York, NY (United States); Memorial Sloan Kettering Cancer Center, Department of Pediatrics, New York, NY (United States)

    2016-05-15

    GPA33 is a colorectal cancer (CRC) antigen with unique retention properties after huA33-mediated tumor targeting. We tested a pretargeted radioimmunotherapy (PRIT) approach for CRC using a tetravalent bispecific antibody with dual specificity for GPA33 tumor antigen and DOTA-Bn-(radiolanthanide metal) complex. PRIT was optimized in vivo by titrating sequential intravenous doses of huA33-C825, the dextran-based clearing agent, and the C825 haptens {sup 177}Lu-or {sup 86}Y-DOTA-Bn in mice bearing the SW1222 subcutaneous (s.c.) CRC xenograft model. Using optimized PRIT, therapeutic indices (TIs) for tumor radiation-absorbed dose of 73 (tumor/blood) and 12 (tumor/kidney) were achieved. Estimated absorbed doses (cGy/MBq) to tumor, blood, liver, spleen, and kidney for single-cycle PRIT were 65.8, 0.9 (TI 73), 6.3 (TI 10), 6.6 (TI 10), and 5.3 (TI 12), respectively. Two cycles of PRIT (66.6 or 111 MBq {sup 177}Lu-DOTA-Bn) were safe and effective, with a complete response of established s.c. tumors (100 - 700 mm{sup 3}) in nine of nine mice, with two mice alive without recurrence at >140 days. Tumor log kill in this model was estimated to be 2.1 - 3.0 based on time to 500-mm{sup 3} tumor recurrence. In addition, PRIT dosimetry/diagnosis was performed by PET imaging of the positron-emitting DOTA hapten {sup 86}Y-DOTA-Bn. We have developed anti-GPA33 PRIT as a triple-step theranostic strategy for preclinical detection, dosimetry, and safe targeted radiotherapy of established human colorectal mouse xenografts. (orig.)

  7. Biological evaluation of 177Lu-labeled DOTA-Ala(SO3H)-Aminooctanoyl-Gln-Trp-Ala-Val-N methyl Gly-His-Statine-Leu-NH2 for gastrin-releasing peptide receptor-positive prostate tumor targeting

    Bombesin binds with selectivity and high affinity to a Gastrin-releasing peptide receptor (GRPR), which is highly overexpressed in prostate cancer cells. The present study describes the in vitro and in vivo biological characteristics of DOTA-Ala(SO3H)-Aminooctanoyl-Gln-Trp-Ala-Val-N methyl Gly-His-Statine-Leu-NH2 (DOTA-sBBNA), an antagonist analogue of bombesin peptide for the targeting of GRPR. DOTA-sBBNA was synthesized and labeled with 177Lu as previously published. A saturation assay on PC-3 human prostate cancer cells revealed that the Kd value of the radiolabeled peptide was 1.88 nM with a maximum binding capacity (Bmax) of 289.3 fmol/106 cells. The radio-peptide slowly internalized, and 24.4 ± 0.5% of the total binding was internalized in 4 hr. Biodistribution studies were conducted in healthy and PC-3 xenografted balb/c mice, which showed high uptake and retention of tumor-associated radioactivity in PC-3 xenografted mice. The tumor-to-blood ratio was 126.02 ± 9.36 at 1.5 hr p.i., and was increased to 216.33 ± 61.58 at 24 hr p.i., which means that the radiolabeled peptide was highly accumulated in a tumor and rapidly cleared from the blood pool. The GRPR is also over-expressed in Korean prostate cancer patients. These results suggest that this 177Lu-labeled peptide has promising characteristics for application in nuclear medicine, namely for the diagnosis and treatment of GRPR over-expressing prostate tumors

  8. Dosimetry and microdosimetry of {sup 188} Re-anti-CD20 and {sup 131} I-anti-CD20 for the treatment of No Hodgkin lymphomas; Dosimetria y microdosimetria del {sup 188} Re-anti-CD20 y {sup 131} I-anti-CD20 para el tratamiento de linfomas No Hodgkin

    Torres G, E

    2007-07-01

    The purpose of this investigation was to prepare {sup 131}I-anti-CD20 and {sup 188}Re-anti-CD20 and to estimate the radiation absorbed dose at macro- and micro- level during a NHL treatment. The work was divided in 4 general objectives: 1) preparation of {sup 131}I-anti-CD20 and {sup 188}Re-anti-CD20, 2) application in patients to obtain biokinetic parameters and estimate the organ absorbed doses 3) estimation of the cellular dosimetry using the MIRD methodology and the MCNP4C2 code and 4) estimation of the cellular microdosimetry using the NOREC code. {sup 188}Re-anti-CD20 was prepared by a direct labelling method using sodium tartrate as a weak ligand. To evaluate the biological recognition a comparative study of the in vitro binding of {sup 188}Re-anti-CD20, {sup 125}I-anti-CD20 (positive control) and {sup 188}Re-anti-CEA (negative control) to normal B Iymphocytes was performed. Biodistribution studies in normal mice were accomplished to assess the in vivo Re-anti-CD20 complex stability. The binding of ' Re-anti-CD20 to cells was in the same range as '251-anti-CD20 (>80%) considered as the positive control. {sup 188}Re-anti-CD20 and '3'1-anti-CD20 prepared were administered in patients diagnosed with B cell NHL at the Centro Medico Siglo XXI (IMSS). The protocol was approved by the hospital's Medical Ethics Committee. AJI patients signed a consent form after receiving detailed information on the aims of the study. N data were the input for the OLINDA/EXM software to calculate the radiation absorbed dose to organs and whole body. Dosimetric studies indicate that after administration of 6.4 GBq and 4.87 to 8.75 GBq of '3'1-anti-CD20 and {sup 188}Re-anti-CD20 respectively, the absorbed dose to total body would be 0.75 Gy which corresponds to the recommended dose for NHL therapies. The calculated organ absorbed doses indicate that {sup 188}Re-anti-CD20 may be used in radioimmunotherapy without the risk of toxicity to red marrow or

  9. Conventional measurements of GFR using 51Cr-EDTA overestimate true renal clearance by 10 percent

    It is widely believed that measurement of the area under the plasma clearance curve (AUC) following a single intravenous injection of chromium-51 labelled ethylene diamine tetra-acetic acid (51Cr-EDTA) is a gold standard method for determining glomerular filtration rate (GFR). However, there are reports that 51Cr-EDTA may have a significant extrarenal clearance. The aim of this study was to identify the non-renal component of 51Cr-EDTA plasma clearance contributing to the AUC measurement of GFR. Seventy healthy postmenopausal women (mean age 60 years, range 45-79 years) were injected with 3 MBq 51Cr-EDTA and 0.25 MBq iodine-125 labelled human serum albumin and 11 blood samples taken between 0 and 4 h through an indwelling venous cannula. For the first 21 subjects, two complete urine collections were made 0-2 h and 2-4 h after injection, and for the final 49 patients, four 1-h urine collections were made. The mean 51Cr-EDTA total plasma clearance was 84 ml/min (range 50-132 ml/min). The mean ratio (SEM) of urine to total clearance determined from the cumulative 1-, 2-, 3- and 4-h data was 0.903 (0.018), 0.891 (0.013), 0.898 (0.011) and 0.899 (0.010) respectively and remained constant despite the mean urine concentration decreasing from 122% to 15%/litre during this period. A least squares fit to data from the 238 individual urine collections was used to determine the fraction of the total plasma clearance attributable to renal clearance, α0, and the residual urine volume, ΔV. The results were α0=0.910 (95% CI: 0.889-0.932) and ΔV=14 ml (95% CI: -4 to +34 ml). The overestimation of the true renal clearance of 51Cr-EDTA by the AUC method is believed to be due to the failure of the plasma clearance curve to reach the true terminal exponential by 2 h after injection as usually assumed. As a result, conventional measurements of GFR using 51Cr-EDTA overestimate the true renal clearance of tracer by approximately 10%. (orig.)

  10. Steps toward high specific activity labeling of biomolecules for therapeutic application: preparation of precursor [(188)Re(H(2)O)(3)(CO)(3)](+) and synthesis of tailor-made bifunctional ligand systems.

    Schibli, Roger; Schwarzbach, Rolf; Alberto, Roger; Ortner, Kirstin; Schmalle, Helmut; Dumas, Cécile; Egli, André; Schubiger, P August

    2002-01-01

    Two kit preparations of the organometallic precursor [(188)Re(H(2)O)(3)(CO)(3)](+) in aqueous media are presented. Method A uses gaseous carbon monoxide and amine borane (BH(3).NH(3)) as the reducing agent. In method B CO(g) is replaced by K(2)[H(3)BCO(2)] that releases carbon monoxide during hydrolysis. Both procedures afford the desired precursor in yields >85% after 10 min at 60 degrees C. HPLC and TLC analyses revealed 7 +/- 3% of unreacted (188)ReO(4)(-) and 95% with [(188)Re(H(2)O)(3)(CO)(3)](+) under mild reaction conditions (PBS buffer, 60 degrees C, 60 min) at ligand concentrations between 5 x 10(-4) M and 5 x 10(-5) M. Thus, specific activities of 22-220 GBq pe micromol of ligand could be achieved. Incubation of the corresponding Re-188 complexes in human serum at 37 degrees C revealed stabilities between 80 +/- 4% and 45 +/- 10% at 24 h, respectively, and 63 +/- 3% and 34 +/- 3% at 48 h postincubation in human serum depending on the chelating system. Decomposition product was mainly (188)ReO(4)(-). The routine kit-preparation of the precursor [(188)Re(H(2)O)(3)(CO)(3)](+) in combination with tailor-made ligand systems enables the organometallic labeling of biomolecules with unprecedented high specific activities. PMID:12121130

  11. Intestinal permeability to [51Cr]EDTA in children with cystic fibrosis

    Intestinal permeability was investigated in 14 children with cystic fibrosis making use of [51Cr]EDTA as probe molecule. Ten normal young adults and 11 children served as controls. After oral administration of [51Cr]EDTA, 24 h urine was collected. Urinary radioactivity was calculated and results expressed as percentage of oral dose excreted in 24 h urine. Mean and SEM were as follows: 2.51 +/- 0.21, 2.35 +/- 0.24, and 13.19 +/- 1.72 for control children, normal adults, and cystic fibrosis patients, respectively. The permeability differences between cystic fibrosis patients and either control children or control adults are significant (p less than 0.001)

  12. Instant capture of recoil 51Cr(III) from neutron activated K2CrO4

    A new method of measuring the initial 51Cr(III) produced from nuclear recoil of K2CrO4 was developed. In this method K2CrO4 was mixed with MgO in the presence of a small amount of water, and the mixture was irradiated in a nuclear reactor. After irradiation, the mixture was dissolved in water, and MgO precipitate was separated from the solution. The yield of recoil 51Cr(III) could be calculated from the 51Cr activity in the precipitate measured. On the other hand, the yield of retention of 51Cr as chromate could be calculated from the activity found in the supernatant. The 51Cr(III) yield thus obtained is almost a factor of 2 higher than observed in pure K2CrO4 without mixing with MgO, irradiated under the same condition. Another important observation is that the 51Cr(III) yield is independent of irradiation time in presence of MgO. Without MgO the observed 51Cr(III) yield decreases with increasing irradiation time, suggesting possible oxidation of Cr(III) to chromate during irradiation. This variation is not observed in the system of K2CrO4 containing MgO, indicating that the initial Cr(III) is adsorbed immediately after nuclear recoil by MgO and is protected from oxidation by gamma radiation. (author) 4 refs.; 4 figs.; 2 tabs

  13. INTERNAL FRICTION OF 51CrV4 SHAFT INFLUENCED BY THERMO-MECHANICAL COUPLING

    J. G(o)ken; M. Maikranz-Valentin; K. Steinhoff; T.S. Pavlova; T.V. Ivleva; I.S. Golovin

    2008-01-01

    The simultaneous influence of thermal and mechanical treatment was applied to produce a geometrically complex shaft from 51CrV4 steel leading to the formation of microstructures which were significantly different from each other. These microstructural differences were accompanied by a local change of mechanical properties in terms of hardness, electrical resistivity and especially internal friction. The Snoek-Koster peak was recognized and analyzed in the structure of this steel.

  14. Modification of leukocyte adherence inhibition (LAI) assay with 51Cr-labelled leukocytes

    Leukocyte adherence inhibition was measured by a new modified radioisotopic technique. Peripheral blood leukocytes were isolated and labelled with 51Cr. These leukocytes were incubated with medium or buffer alone and with medium or buffer containing tumor antigen or gluten. The glass surface for the adherence was prepared carefully. In all samples the adherence of leukocytes occured under the same conditions. The results of the LAI assay with gluten and stomach cancer antigen are reported and discussed. (author)

  15. Blood loss estimation in Schistosoma incognitum by the use of 51Cr labelled red cells

    C42 Red blood cells labelled with 51Cr were used to study the pathophysiology of S. incognitum infection. Blood volume, cell volume, faecal blood excretion and the half life of the red cells were determined. It was shown that in rabbits infected with the blood fluke, there was loss of blood, which may result in the development of anaemia in the infected animals. (author)

  16. Burn-up cross sections of 51Cr, 59Fe, 65Zn, 86Rb, 103Ru

    Targets of Cr, Fe, Zn, Rb, and Ru were irradiated in the hydraulic tube of the Oak Ridge HFIR reactor at a neutron flux of 2.6 x 1015 n/cm2sec for 1 day and 20 days. The reactor burn-up cross sections (in barns) of the radioactive product nuclides are: 51Cr, 59Fe, 65Zn, 60 +- 30; 86Rb, 103Ru, <20

  17. Studies with nonradioisotopic sodium chromate. II. Single- and double-label 52Cr/51Cr posttransfusion recovery estimations

    A recently developed nonradioisotopic 52Cr technique was used to measure either red cell volume or posttransfusion recovery of stored red cells. The experimental method uses Zeeman electrothermal atomic absorption spectrophotometry to measure red cell chromium. Results from the 52Cr method were compared with those from 51Cr single-label and 125I-albumin/51Cr double-label procedures using 49-day AS-1 red cell concentrates drawn and prepared according to standard procedures. In the first group of five donors, red cell volume was estimated concurrently with both 52Cr-labeled fresh red cells and 125I-albumin. The latter measured plasma volume from which red cell volume was estimated on the basis of the hematocrit (125I red cell volume). 51Cr-labeled stored red cells were transfused to measure posttransfusion recoveries. The correlation between 52Cr and 125I red cell volumes was significant (r = 0.68, p less than 0.01), and, in this group, the differences were not significant (p less than 0.05). Twenty-four-hour posttransfusion recoveries of 51Cr-labeled stored red cells averaged 66 +/- 5 percent when measured with the 125I/51Cr technique and 69 +/- 8 percent when measured with the 52Cr/51Cr method. In the second group of five donors, red cell volume was estimated by the 125I-albumin technique, and the posttransfusion recovery of stored red cells was quantitated by 51Cr- and 52Cr-labeled stored cells simultaneously. In this group, posttransfusion recoveries with 125I/51Cr averaged 73 +/- 7 percent; with 125I/52Cr, they averaged 75 +/- 10 percent. Using the single-label method of calculation, recoveries averaged 76 +/- 7 and 75 +/- 10 percent for the 51Cr and 52Cr methods, respectively

  18. Report on the 2nd Research Coordination Meeting on The Development of Therapeutic Radiopharmaceuticals Based on 188Re and 90Y for Radionuclide. Working Document

    Radionuclide therapy is practiced for the treatment of malignant disorders of various organs and tissues as well as for treating certain other diseases such as rheumatoid arthritis. Advances in understanding tumor biology as well as developments in peptide chemistry and monoclonal antibody technology are opening new opportunities for the development of therapeutic radiopharmaceuticals, thereby widening the scope of radionuclide therapy. In addition, particulate based radiopharmaceuticals are useful for treating hepatocarcinoma as well as in radiation synovectomy. With the establishment of new products the demand and application of therapeutic nuclear medicine is expected to grow rapidly. While there are a large number of radioisotopes proposed for targeted therapy, practical considerations had been limiting the number of usable isotopes. Generator-produced radionuclides are an attractive option for the large scale on-site availability of therapeutic isotopes. The IAEA’s CRP on the ‘Development of generator technologies for therapeutic radionuclides’ (2004-2007) was successful in developing technologies for the preparation of 188W/188Re and 90Sr/90Y generators for eluting 188Re and 90Y of high radionuclidic and chemical purity usable for research applications in the development of therapeutic radiopharmaceuticals. The IAEA’s CRP on ‘The development of therapeutic radiopharmaceuticals based on 188Re and 90Y for radionuclide therapy’ was formulated to focus on enhancing the capacity of the 90Sr/90Y generator; to develop and validate quality control methods for the generator eluate; and to develop therapeutic radiopharmaceuticals based on 188Re and 90Y. The first RCM of the CRP was held in Polatom, Warsaw, Poland from 30 June to 4 July 2008. The meeting reviewed the work going on in the different participating laboratories, and the facilities, expertise and capabilities of the different participating groups, and formulated the work plan of the CRP. The work

  19. 188Re-ZHER2:V2, a promising targeting against HER2-expressing tumors: in vitro and in vivo assessment

    Full text of publication follows. Aim: Rhenium-188 (T1/2 =17 h) is a promising radionuclide for therapy applications. This generator-produced high energy beta-emitter is suitable for eradication of bulky non-operable tumors. Low abundance 155 KeV photons permit SPECT imaging of biodistribution of Rhenium-188 labeled targeting agents during therapy for personalized dosimetry. Affibody molecules are small (7 kDa) non-immunoglobulin scaffold proteins with good tumor targeting properties and favorable kinetics. Optimization of the targeting properties of Technetium-99m and Rhenium-188 labeled anti-HER2 affibody molecules demonstrated that the variant with C-terminal glycyl-glycyl-glycyl-cysteine (-GGGC) chelating sequence (designated ZHER2:V2) has the best biodistribution profile in vivo and the lowest renal uptake of radioactivity. The aim of this study is to evaluate 188Re-ZHER2:V2 as a potential candidate for affibody-based radionuclide targeted therapy against HER2-expressing tumors. Methods: ZHER2:V2 was labeled with Rhenium-188 using gluconate-containing kit at pH 4.2. Binding specificity to HER2-expressing cells in vitro was evaluated. Targeting of HER2-over-expressing SKOV-3 ovarian carcinoma xenografts in NMRI nu/nu female mice was studied for a preliminary dosimetry assessment. Results: The labeling method provided labeling yields over 95%. The release of free 188Re was negligible after incubation in serum. Binding of 188Re-ZHER2:V2 to living SKOV-3 cells was HER2-mediated (KD = 13 pM). The biodistribution study showed a rapid blood clearance (1.2±0.1 %IA/g at 1 h p.i.). Bone uptake was 1.2±0.1 %IA/g at 1 h p.i. and remained below 0.15 %IA/g after 4 h p.i. The tumor uptake was 11±3, 10±1, 4±2 and 1.6±0.5 %IA/g at 1, 4, 24 and 48 h p.i., respectively. Pre-saturation of HER2 in xenografts by a pre-injection of a large excess of non-labeled affibody molecules reduced tumor uptake to 2±0.1 %IA/g at 4 h p.i., suggesting receptor specificity of the targeting

  20. 188Re- and 99mTc-MAG3 as prosthetic groups for labeling amines and peptides Approaches with pre- and postconjugate labeling

    Either radiolabeled Tc-99m- or Re-188-labeled MAG3-4-nitrophenylester or unlabeled Bz-MAG3-4-nitrophenylester was reacted with amines and peptides to follow a pre- or a postconjugate radiolabeling route, respectively. The model compounds were N'-t-butyloxycarbonyl-1,6-diaminohexane (DH-Boc) and a Lysprotected derivative of the somatostatin analog RC-160 (cyclic D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH2). In the case of labeling DH-Boc, both the preconjugate labeling and the postconjugate labeling were found by using analytical HPLC to provide identical radiolabeled compounds regardless whether Re-188 or Tc-99m was used. The results are supported by infrared and mass-spectral data obtained from compounds synthesized using stable rhenium. The 188Re- or 99mTc-MAG3-RC-160 somatostatin analog were synthesized following the preconjugate labeling route and subsequent removal of the protecting group. Biodistributions of 188Re- and 99mTc-MAG3-RC-160 were evaluated in normal and tumor-bearing mice, and were similar to those of radioiodinated 131I-RC-160. All radiolabeled analogs of RC-160 were rapidly cleared from the blood and were excreted through the hepatobiliary system with very little normal organ uptake. The tumor uptake (PC-3, human prostate adenocarcinoma) of systemically administered Re-188-MAG3-RC160 was very low, and it reached only 0.28% injected dose/g (%IDg) at 24 h postinjection, similar to what was obtained with I-131-RC-160. Intratumor injections resulted in significant tumor retentions (9.3% ID/g at 24 h)

  1. Evaluation of S-values and dose distributions for 90Y, 131I, 166Ho, and 188Re in seven lobes of the rat liver

    Purpose: Rats have been widely used in radionuclide therapy research for the treatment of hepatocellular carcinoma (HCC). This has created the need to assess rat liver absorbed radiation dose. In most dose estimation studies, the rat liver is considered as a homogeneous integrated target organ with a tissue composition assumed to be similar to that of human liver tissue. However, the rat liver is composed of several lobes having different anatomical and chemical characteristics. To assess the overall impact on rat liver dose calculation, the authors use a new voxel-based rat model with identified suborgan regions of the liver. Methods: The liver in the original cryosectional color images was manually segmented into seven individual lobes and subsequently integrated into a voxel-based computational rat model. Photon and electron particle transport was simulated using the MCNPX Monte Carlo code to calculate absorbed fractions and S-values for 90Y, 131I, 166Ho, and 188Re for the seven liver lobes. The effect of chemical composition on organ-specific absorbed dose was investigated by changing the chemical composition of the voxel filling liver material. Radionuclide-specific absorbed doses at the voxel level were further assessed for a small spherical hepatic tumor. Results: The self-absorbed dose for different liver lobes varied depending on their respective masses. A maximum difference of 3.5% was observed for the liver self-absorbed fraction between rat and human tissues for photon energies below 100 keV. 166Ho and 188Re produce a uniformly distributed high dose in the tumor and relatively low absorbed dose for surrounding tissues. Conclusions: The authors evaluated rat liver radiation doses from various radionuclides used in HCC treatments using a realistic computational rat model. This work contributes to a better understanding of all aspects influencing radiation transport in organ-specific radiation dose evaluation for preclinical therapy studies, from tissue

  2. Radioassay of granulocyte chemotaxis. Studies of human granulocytes and chemotactic factors. [/sup 51/Cr tracer technique

    Gallin, J.I.

    1974-01-01

    The above studies demonstrate that the /sup 51/Cr radiolabel chemotactic assay is a relatively simple and objective means for studying leukocyte chemotaxis in both normal and pathological conditions. Application of this method to studies of normal human chemotaxis revealed a relatively narrow range of normal and little day-to-day variability. Analysis of this variability revealed that there is more variability among the response of different granulocytes to a constant chemotactic stimulus than among the chemotactic activity of different sera to a single cell source. Utilizing the /sup 51/Cr radioassay, the abnormal granulocyte chemotactic behavior reported in Chediak-Higashi syndrome and a patient with recurrent pyogenic infections and mucocutaneous candidiasis has been confirmed. The /sup 51/Cr chemotactic assay has also been used to assess the generation of chemotactic activity from human serum and plasma. The in vitro generation of two distinct chemotactic factors were examined; the complement product (C5a) and kallikrein, an enzyme of the kinin-generating pathway. Kinetic analysis of complement-related chemotactic factor formation, utilizing immune complexes or endotoxin to activate normal sera in the presence or absence of EGTA as well as kinetic analysis of activation of C2-deficient human serum, provided an easy means of distinguishing the classical (antibody-mediated) complement pathway from the alternate pathway. Such kinetic analysis is necessary to detect clinically important abnormalities since, after 60 min of generation time, normal chemotactic activity may be present despite complete absence or inhibition of one complement pathway. The chemotactic factor generated by either pathway of complement activation appears to be predominately attributable to C5a.

  3. Calorimetric method for determination of {sup 51}Cr neutrino source activity

    Veretenkin, E. P., E-mail: veretenk@inr.ru; Gavrin, V. N.; Danshin, S. N.; Ibragimova, T. V.; Kozlova, Yu. P.; Mirmov, I. N. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

    2015-12-15

    Experimental study of nonstandard neutrino properties using high-intensity artificial neutrino sources requires the activity of the sources to be determined with high accuracy. In the BEST project, a calorimetric system for measurement of the activity of high-intensity (a few MCi) neutrino sources based on {sup 51}Cr with an accuracy of 0.5–1% is created. In the paper, the main factors affecting the accuracy of determining the neutrino source activity are discussed. The calorimetric system design and the calibration results using a thermal simulator of the source are presented.

  4. Enhanced intestinal permeability to 51Cr-labeled EDTA in dogs with small intestinal disease.

    Hall, E J; Batt, R M

    1990-01-01

    Intestinal permeability in dogs with small intestinal disease was measured by quantitation of 24-hour urinary excretion of 51Cr-labeled EDTA following intragastric administration. Permeability was high in dogs with a variety of naturally acquired small intestinal diseases including wheat-sensitive enteropathy of Irish Setters, small intestinal bacterial over-growth, and giardiasis, and permeability was decreased after successful treatment. These findings indicate that the assessment of intestinal permeability may be a useful technique for detecting small intestinal disease and for monitoring the efficacy of treatment in dogs. PMID:2104825

  5. 166Ho and 90Y labeled 6D2 monoclonal antibody for targeted radiotherapy of melanoma: Comparison with 188Re radiolabel

    Introduction: An approach to radioimmunotherapy (RIT) of metastatic melanoma is the targeting of melanin pigment with monoclonal antibodies (mAbs) to melanin radiolabeled with therapeutic radionuclides. The proof of principle experiments were performed using a melanin-binding antibody 6D2 of IgM isotype radiolabeled with a β emitter 188Re and demonstrated the inhibition of tumor growth. In this study we investigated the efficacy of 6D2 antibody radiolabeled with two other longer lived β emitters 90Y and 166Ho in treatment of experimental melanoma, with the objective to find a possible correlation between the efficacy and half-life of the radioisotopes which possess high energy β (Emax > 1.5 MeV) emission properties. Methods: 6D2 was radiolabeled with longer lived β emitters 90Y and 166Ho in treatment of experimental melanoma in A2058 melanoma tumor-bearing nude mice. The immunoreactivity of the radiolabeled 6D2 mAb, its in vitro binding to the MNT1 human melanoma cells, the biodistribution and therapy in A2058 human melanoma bearing nude mice as well as dosimetry calculations were performed. Results: When labeled with the longer lived 90Y radionuclide, the 6D2 mAb did not produce any therapeutic effect in tumor bearing mice while the reduction of the tumor growth by 166Ho-6D2 was very similar to the previously reported therapy results for 188Re-6D2. In addition, 166Ho-labeled mAb produced the therapeutic effect on the tumor without any toxic effects while the administration of the 90Y-labeled radioconjugate was toxic to mice with no appreciable anti-tumor effect. Conclusions: 166Ho-labeled mAb to melanin produced some therapeutic effect on the tumor without any toxic effects while the administration of the 90Y-labeled radioconjugate was toxic to mice with no appreciable anti-tumor effect. We concluded that the serum half-life of the 6D2 carrier antibody matched well the physical half-life of 166Ho to deliver the tumoricidal absorbed dose to the tumor. Further

  6. Reversibility of increased intestinal permeability to 51Cr-EDTA in patients with gastrointestinal inflammatory diseases

    Intestinal permeability in adults with inflammatory gastrointestinal diseases was investigated by measuring the 24-h urinary excretion of orally administered 51Cr-EDTA. Eighty controls along with 100 patients with Crohn's disease, 46 patients with ulcerative colitis, 20 patients with gluten-sensitive enteropathy, and 18 patients with other diseases were studied. In controls, the median 24-h excretion was 1.34%/24 h of the oral dose. Patients with Crohn's disease (median 2.96%/24 h), ulcerative colitis (median 2.12%/24 h), and untreated gluten-sensitive enteropathy (median 3.56%/24 h) had significantly elevated urinary excretion of the probe compared to controls (p less than 0.0001). Increased 24-h urinary excretion of 51Cr-EDTA had a high association with intestinal inflammation (p less than 0.0001). Test specificity and sensitivity were 96% and 57%, respectively. A positive test has a 96% probability of correctly diagnosing the presence of intestinal inflammation, whereas a negative test has a 50% probability of predicting the absence of disease

  7. Uptake studies of environmentally hazardous {sup 51}Cr in Mung beans

    Banerjee, Anupam [Department of Botany, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700019 (India); Nayak, Dalia [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Chakrabortty, Dipanwita [Sikkim Manipal University, A 15, Paryavaran Complex, New Delhi 110030 (India); Lahiri, Susanta [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)], E-mail: susanta.lahiri@saha.ac.in

    2008-01-15

    Attempt has been made to study the accumulation behaviour of a common plant, Mung bean (Vigna radiata) towards Cr(III) and Cr(VI) to have an insight on the migration and bio-magnification of Cr. For this purpose healthy germinated Mung bean seeds were sown in the sand in the presence of Hoagland's nutrient solution containing measured amount of K{sub 2}{sup 51}Cr{sub 2}O{sub 7} and {sup 51}Cr(NO{sub 3}){sub 3}.9H{sub 2}O. Growth rate was also studied in the presence and absence of phosphate salts in the medium. It has been found that the transfer of chromium from soil to plant is significantly low (maximum 5% for both Cr(III) and Cr(VI)). Maximum accumulation of Cr occurs in the root with respect to the total chromium accumulation by the plant. Other parts of the Mung bean plant, e.g. cotyledons, shoot and leaves, show negligible accumulation. Therefore, the chance of direct intake of Cr through food as well as through the grazing animals to human body is less. - The chance of bio-magnification of Cr(III) or Cr(VI) to human body via direct or indirect intake of Mung bean is negligible.

  8. Fecal excretion of radiolabelled (51CrCl 3) proteins in patients with Crohn's disease

    Intestinal leakage of plasma proteins was studied in 69 patients with Crohn's disease. In vivo labelling of plasma proteins was performed by intravenous injection of trace amounts of 51CrCl 3. Complete fecal collection was done for 5 days, carefully avoiding contamination with urine. The daily fecal radioactivity was measured in a whole-body counter and expressed as a percentage of given dose. In patients with a classic localization of the disease the mean fecal excretion of radiolabelled proteins was 2.8%. The excretion was significantly higher in patients with extensive ileojejunal involvement and in patients with a toal colitis, but not different from that in patients with prestomal recurrent ileal disease. A close correlation was found between fecal excretion of 51Cr and extent of the small-intestinal disease as measured at laparotomy. A highly significant inverse relationship was also demonstrated between fecal protein excretion and serum albumin concentration in patients without septic complications of the disease. A pre-existing septic complications made the patients hypoalbuminemic despite limited intestinal loss of protein. It is concluded that estimation of intestinal protein loss is a sensitive and simple test for assessment of the extent of the small-intestinal involvement in patients with Crohn's disease. The test may be of value in patients with unclear radiologic findings and in patients with hypoalbuminemia of unknown cause. 25 refs., 3 figs

  9. Use of a /sup 51/Cr technique to detect gastrointestinal microbleeding associated with nonsteroidal antiinflammatory drugs

    Lussier, A.; Arsenault, A.; Varady, J.; de Medicis, R.; Lussier, Y.; LeBel, E.

    1987-02-01

    Of techniques used to evaluate gastrointestinal (GI) bleeding, use of radiochromium (/sup 51/Cr)-tagged erythrocytes is the most quantitative and scientifically acceptable method. The value of this technique as well as systematic errors possible with its use are discussed. The medical literature concerning /sup 51/Cr evaluation of GI microbleeding with naproxen therapy is critically reviewed. We suggest that future studies using this technique be parallel, randomized, double-blind, and include a 1-week placebo baseline phase for all subjects. Treatment with nonsteroidal antiinflammatory drugs (NSAIDs) should last 3 to 4 weeks. A parallel group of subjects should receive placebo throughout the study. For valid statistical analyses, randomization must achieve baseline comparability of weight, height, age, and sex in the treatment groups. Data transformations may be necessary to satisfy the assumptions of the statistical model. Following these guidelines will enable investigators to better evaluate GI microbleeding during treatment with naproxen or other NSAIDs, and, hopefully, to establish the safety profiles of these drugs.37 references.

  10. Use of a 51Cr technique to detect gastrointestinal microbleeding associated with nonsteroidal antiinflammatory drugs

    Of techniques used to evaluate gastrointestinal (GI) bleeding, use of radiochromium (51Cr)-tagged erythrocytes is the most quantitative and scientifically acceptable method. The value of this technique as well as systematic errors possible with its use are discussed. The medical literature concerning 51Cr evaluation of GI microbleeding with naproxen therapy is critically reviewed. We suggest that future studies using this technique be parallel, randomized, double-blind, and include a 1-week placebo baseline phase for all subjects. Treatment with nonsteroidal antiinflammatory drugs (NSAIDs) should last 3 to 4 weeks. A parallel group of subjects should receive placebo throughout the study. For valid statistical analyses, randomization must achieve baseline comparability of weight, height, age, and sex in the treatment groups. Data transformations may be necessary to satisfy the assumptions of the statistical model. Following these guidelines will enable investigators to better evaluate GI microbleeding during treatment with naproxen or other NSAIDs, and, hopefully, to establish the safety profiles of these drugs.37 references

  11. Intestinal permeability to (/sup 51/Cr)EDTA in children with Crohn's disease and celiac disease

    Turck, D.; Ythier, H.; Maquet, E.; Deveaux, M.; Marchandise, X.; Farriaux, J.P.; Fontaine, G.

    1987-07-01

    (/sup 51/Cr)EDTA was used as a probe molecule to assess intestinal permeability in 7 healthy control adults, 11 control children, 17 children with Crohn's disease, and 6 children with untreated celiac disease. After subjects fasted overnight, 75 kBq/kg (= 2 microCi/kg) /sup 51/Cr-labeled EDTA was given by mouth; 24-h urinary excretion of (/sup 51/Cr)EDTA was measured and expressed as a percentage of the total oral dose. Mean and SD were as follows: control adults 1.47 +/- 0.62, control children 1.59 +/- 0.55, and patients with Crohn's disease or celiac disease 5.35 +/- 1.94. The difference between control children and patients was statistically significant (p less than 0.001). These results show that intestinal permeability to (/sup 51/Cr)EDTA is increased among children with active or inactive Crohn's disease affecting small bowel only or small bowel and colon, and with untreated celiac disease. The (/sup 51/Cr)EDTA permeability test could facilitate the decision to perform more extensive investigations in children suspected of small bowel disease who have atypical or poor clinical and biological symptomatology.

  12. Evaluation of the surface contamination density with 51Cr by direct measurement method using a GM survey-meter

    It is difficult to detect a low level contamination with 51Cr using a scintillation survey-meter because background counting rate of the survey-meter is high and emitted rate of γ-rays (0.320 MeV) from 51Cr is less than 10%. We examined whether a surface contamination with 51Cr can be detected directly with a GM survey-meter. As the result, the detection efficiency and detection limit of the GM survey-meter against the surface contamination were more than 0.6%(4π) and 4.6 Bq/cm2, respectively. From measurement of transmittance of radiations from 51Cr against poly (vinylidene chloride) seat, it became clear that the majority (about 98%) of detected radiations with the GM survey-meter is characteristic X-rays. These results show that the GM survey-meter can be used as a detector to check a surface contamination with 51Cr in controlled area. (author)

  13. Bioaccumulation of Chromium by Perna Viridis from Jakarta Bay Base on Radiotracer 51Cr Study

    The research of bioaccumulation chromium of Perna viridis from Jakarta Bay using 51Cr radiotracer have been done. The experiment was carried out by 3 steps such as: uptake, depuration and modelling. The result of experiment shown that Perna viridis can be used as bioindicator of chromium because its capability to accumulate Cr. Its concentration factor, uptake rate and depuration rate were 148.36 to 414.5, 14.836 to 65.754 μg per days and 9.04 to 15.48 % per days respectively. The value of BCF was under 500 so Perna viridis can not be used for environmental risk assesment. The result of modeling was find the Concentration Factor were 106 to 367 and the its decreasing from Perna viridis tissue can be 90 % after 14 days of depuration. (author)

  14. Mathematical analysis of /sup 51/Cr-labelled red cell survival curves in congenital haemolytic anaemias

    Kasfiki, A.G.; Antipas, S.E.; Dimitriou, P.A.; Gritzali, F.A.; Melissinos, K.G.

    1982-04-01

    The parameters of /sup 51/Cr labelled red cell survival curves were calculated in 26 patients with homozygous ..beta..-thalassaemia, 8 with sickle-cell anaemia and 3 with s-..beta..-thalassaemia, using a non-linear weighted least squares analysis computer program. In thalassaemic children the calculated parameters denote that the shorting of the mean cell life is due to early senescence alone, while there is some evidence that in thalassaemic adults additional extracellular destruction mechanisms participate as well. Red cell survival curves from patients with sickle-cell anaemia and s-..beta..-thalassaemia resemble each other, while their parameters indicate an initial rapid loss of radioactivity, early senescence and the presence of extracellular red cell destruction factors.

  15. Mathematical analysis of 51Cr-labelled red cell survival curves in congenital haemolytic anaemias

    The parameters of 51Cr labelled red cell survival curves were calculated in 26 patients with homozygous β-thalassaemia, 8 with sickle-cell anaemia and 3 with s-β-thalassaemia, using a non-linear weighted least squares analysis computer program. In thalassaemic children the calculated parameters denote that the shorting of the mean cell life is due to early senescence alone, while there is some evidence that in thalassaemic adults additional extracellular destruction mechanisms participate as well. Red cell survival curves from patients with sickle-cell anaemia and s-β-thalassaemia resemble each other, while their parameters indicate an initial rapid loss of radioactivity, early senescence and the presence of extracellular red cell destruction factors. (orig.)

  16. Forces in Hard Turning of 51CrV4 with Wiper Cutting Tool

    HE Xinfeng; WU Su; Hubert Kratz

    2006-01-01

    For precision machining, the hard turning process is becoming an important alternative to some of the existing grinding processes. This paper presents an analytical model for predicting cutting forces in hard turning of 51CrV4 with hardness of 68 HRC. The cutting tool used is made from cubic boron nitride (CBN) with a wiper cutting edge. Formulas for differential chip loads are derived for three different situations, depending on the radial depth of cut. The cutting forces are determined by integrating the differential cutting forces over the tool-workpiece engagement domain. For validation, cutting forces predicted by the model were compared with experimental measurements, and most of the results agree quite well.

  17. Application of 51Cr-RBC life span study and surface counting in blood diseases

    Present article summarized the RBC life span and liver, spleen surface counting in 274 cases of blood diseases. Whole blood labelling of 51Cr labelled auto or normal O type blood was used. The results showed that there was a shortening of the apparent survival time with different magnitude in various blood diseases, therefore it can be used for understanding the severity of hemolytic anemia, detection of latent hemolysis and also the investigation of the destruction and survival of RBC in other blood diseases. The surface counting of spleen, liver and precordium denoted that the S/P, S/L ratio was highest in hyperspleenism, consecutively various hemolytic anemia and cirrhosis of liver, hence this test can be used as an indication for splenectomy

  18. Preliminary results from the 51Cr neutrino source experiment in GALLEX

    The GALLEX collaboration performed a second 51Cr neutrino source experiment during fall 1995. The full results from this second source experiment will no