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Sample records for 11c-l-methionine pet tumor

  1. Brain protein synthesis in normal and demented patients. A study by P.E.T. with 11C-L methionine

    A compartmental model representing protein synthesis in the brain was validated experimentally in 9 baboons. After sequential injections of 11C, 3H and 14C methionines on the same animal, followed by P.E.T. recording of the γ activity in a chosen brain section with time, the distribution of methionine injected into the different compartments of the model after a bolus was measured by crushing and precipitation with T.C.A. The agreement between direct in vitro findings and computed results is excellent. This method of studying brain protein synthesis in vivo was applied to 28 Alzheimer dementia cases and 20 normal subjects of the same age. The correlation between the results of clinical and psychometric tests and the brain protein synthesis activity confirms an anomaly in this biochemical synthesis process during the illness. A 65% fall in activity may be found in the frontal lobes of certain patients

  2. Local cerebral metabolic rate of 11C-L-Methionine in early stages of dementia, schizophrenia, Parkinson's disease

    A dynamic three-compartment model of methionine metabolism in brain was applied in human patients using 11C-L-Methionine and positron emission tomography (P.E.T). Psychometric evaluations of demented patients were correlated with a significant diminution of protein synthesis in the frontal area. This diminution was lower in ebephrenic patients (-17%) but was consistent with the results obtained with 18F glucose. No significant abnormality was detected in patients with Parkinson disease

  3. Positron emission tomography (PET) study of patients with pituitary adenoma using labeled amino acid

    Four cases with pituitary adenomas were studied using 11C-L-methionine (C-11 Met) positron-emission tomography (PET). The C-11 Met was intravenously administered at a dose of 0.6 mCi/kg. The uptake of the tracer for tumors was calculated on the PET images 45 min after the injection; the uptake index was represented as a percentage of the total count in the arterial blood over a period of 45 min. In all cases, the C-11 Met accumulated intensely in the tumor regions; the PET images clearly delineated the extent of the tumor. The C-11 Met uptake index for pituitary adenomas varied widely from 3.94 x 10-2% to 15.36 x 10-2%, with a mean of 7.87 x 10-2%. These indices for the tumors increased markedly in comparison with that of the contralateral left temporal gray matter as a nontumor region (1.89 x 10-2% to 2.43 x 10-2% with a mean of 2.06 x 10-2%). In a case of prolactinoma, repeated PET following bromocriptine treatment showed a decrease in the C-11 Met uptake index; this decrease reflected changes in the serum prolactin value. In another case with ACTH-producing adenoma, the T/NT (tumor/nontumor) ratio fell from 3.44 to 2.40; however, the C-11 Met index remained unchanged. C-11 Met PET images facilitate determining the extent of pituitary adenomas and the monitoring of tumor response to treatment. Further application may give useful knowledge on the amino-acid metabolism of the tumor. (author)

  4. Positron emission tomography (PET) study of patients with pituitary adenoma using labeled amino acid

    Mineura, Katsuyoshi; Sasajima, Toshio; Sakamoto, Tetsuya; Kowada, Masayoshi (Akita Univ. (Japan). Hospital); Shishido, Fumio; Uemura, Kazuo

    1989-12-01

    Four cases with pituitary adenomas were studied using {sup 11}C-L-methionine (C-11 Met) positron-emission tomography (PET). The C-11 Met was intravenously administered at a dose of 0.6 mCi/kg. The uptake of the tracer for tumors was calculated on the PET images 45 min after the injection; the uptake index was represented as a percentage of the total count in the arterial blood over a period of 45 min. In all cases, the C-11 Met accumulated intensely in the tumor regions; the PET images clearly delineated the extent of the tumor. The C-11 Met uptake index for pituitary adenomas varied widely from 3.94 x 10{sup -2}% to 15.36 x 10{sup -2}%, with a mean of 7.87 x 10{sup -2}%. These indices for the tumors increased markedly in comparison with that of the contralateral left temporal gray matter as a nontumor region (1.89 x 10{sup -2}% to 2.43 x 10{sup -2}% with a mean of 2.06 x 10{sup -2}%). In a case of prolactinoma, repeated PET following bromocriptine treatment showed a decrease in the C-11 Met uptake index; this decrease reflected changes in the serum prolactin value. In another case with ACTH-producing adenoma, the T/NT (tumor/nontumor) ratio fell from 3.44 to 2.40; however, the C-11 Met index remained unchanged. C-11 Met PET images facilitate determining the extent of pituitary adenomas and the monitoring of tumor response to treatment. Further application may give useful knowledge on the amino-acid metabolism of the tumor. (author).

  5. Pioneering and fundamental achievements on the development of positron emission tomography (PET) in oncology

    Positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG), a glucose analog, is widely used throughout the world as an indispensable imaging modality for the management of cancer treatment. This article reviews the pioneering achievements of PET in oncology with a focus on the development of PET that occurred from 1980 through the early-1990s. 18F-FDG was first applied for imaging of animal tumors in 1980 and for brain tumor imaging clinically in 1982. 18F-FDG enabled to visualize liver metastasis as clear positive image that could not be obtained by conventional nuclear imaging. Subsequently, 18F-FDG was used for imaging various cancers, such as lung, pancreas, colorectal and hepatoma. 11C-L-methionine (11C-MET) that reflects amino acid transport of cancers has an advantage that its uptake is lower in the brain and inflammatory tissue compared to 18F-FDG, and was first applied for imaging lung cancer and brain tumor. 18F-FDG and 11C-MET were proved to be sensitive tracers that can be used to objectively evaluate the effectiveness of cancer treatment. The diagnostic accuracy of PET, which is critical in clinical practice, was evaluated for the differential diagnosis of malignant and benign lung nodules using 18F-FDG or 11C-MET. In addition to 18F-FDG and 11C-MET, many radiopharmaceuticals were developed, such as 18F-labled thymidine analogs for evaluating proliferative activity, 18F-fluoromisonidazole for imaging of hypoxia, and 18F-fluorodeoxygalactose for evaluating liver-specific galactose metabolism and for imaging of hepatoma that retains galactose metabolic activity. These early efforts and achievements have greatly contributed to the development and clinical application of 18F-FDG PET in oncology. (author) 113 refs.

  6. PET imaging for evaluating tumor angiogenesis

    Angiogenesis, a main characteristic in tumors, plays an important role in tumor growth and metastasis, which provides a new strategy for tumor treatment. By marking angiogenesis-related receptors, polypeptides, kinases or extracellular matrix proteins as high affinity molecular probes, PET imaging can noninvasively display integrin, VEGF/VEGFR, matrix metalloproteinases (MMPs) and closely monitor tumor angiogenesis and vascular-targeted treatments on the molecular level. In this paper, research progress and future development of PET imaging for evaluating tumor angiogenesis are reviewed. (authors)

  7. Quantitative analysis of PET measurements in tumors

    The positron emission tomograhpy (PET) has been used for the evaluation of the characteristics of various tumors. The role of PET in oncology has been evolved from a pure research tool to a methodology of enormous clinical potential. The unique characteristics of PET imaging make sophisticated quantitation possible. Several quantitative methods, such as standardized uptake values (SUV), simplifield quantitation method, Patlak graphical analysis, and Sokoloff's glucose metabolism measurement, have been used in the field of oncology. However, each quantitative method has limitations of its own. For example, the SUV has been used as a quantitative index of glucose metabolism for tumor classification and monitoring response to treatment, even though it depends on blood glucose level, body configuration of patient, and scanning time. The quantitative methods of PET are reviewed and strategy for implementing these methods are presented

  8. Clinical Application of {sup 18}F-FDG PET and PET-CT in Adrenal Tumor

    Hwang, Kyung Hoon; Choi, Duck Joo; Lee, Min Kyung; Choe, Won Sick [Gachon University Gil Hospital, Incheon (Korea, Republic of)

    2008-12-15

    Adrenal tumors are increasingly detected by widespread use of anatomical imaging such as CT, MRI, etc. For these adrenal tumors, differentiation between malignancy and benignancy is very important. In diagnostic assessment of adrenal tumor, {sup 18}F-FDG PET and PET-CT have been reported to have high diagnostic performance, especially, very excellent performance in evaluation of adrenal metastasis in the oncologic patient. In cases of adrenal incidentalomas, {sup 18}F-FDG PET or PET-CT is helpful if CT or chemical-shift MRI is inconclusive. {sup 18}F-FDG PET and PET-CT may be applied to the patients with MIBG-negative pheochromocytomas. In summary, {sup 18}F-FDG PET and PET-CT are expected to be effective diagnostic tools in the management of adrenal tumor.

  9. The progression of PET/CT in pediatric malignant tumors

    PET/CT has become a major mean for discriminating benign and malignant tumors, finding the primary tumor, staging, restaging, evaluating the response of treatment,predicting the survivors and guiding the operation, radiotherapy, chemotherapy in adults since it was applied in clinic,but it has been rarely applied in children. There exists some difference between internal and overseas in the application of PET/CT in pediatric malignant tumors based on the relative literatures analysis. It is related to the low level of medical radionuclides knowledge and lack of the knowledge about the application of PET/CT in pediatric malignant tumors, and all of these induce less carry out of the pediatric PET/CT imaging, lack of the experience, eventually form a vicious circle. This article mainly described the above two aspects, in order to promote the application of PET/CT in pediatric malignant tumors. (authors)

  10. Non-FDG PET imaging of brain tumors

    HUANG Zemin; GUAN Yihui; ZUO Chuantao; ZHANG Zhengwei; XUE Fangping; LIN Xiangtong

    2007-01-01

    Due to relatively high uptake of glucose in the brain cortex, the use of FDG PET imaging is greatly limited in brain tumor imaging, especially for low-grade gliomas and some metastatic tumours. More and more tracers with higher specificity were developed lately for brain tumor imaging. There are 3 main types of non-FDG PET tracers:amino acid tracers, choline tracers and nucleic acid tracers. These tracers are now widely applied in many aspects of brain tumor imaging. This article summarized the general use of non-FDG PET in different aspects of brain tumor imaging.

  11. PET and endocrine tumors; TEP et tumeurs endocrines

    Rigo, P.; Belhocine, T.; Hustinx, R.; Foidart-Willems, J. [Centre Hospitalier Universitaire de Liege, Service de Medecine Nucleaire et d' Hematologie (Belgium)

    2000-08-01

    The authors review the main indications of PET examination, and specifically of {sup 18}FDG, in the assessment of endocrine tumors: of the thyroid, of the parathyroid, of the adrenal and of the pituitary glands. Neuroendocrine tumors, gastro-entero-pancreatic or carcinoid tumors are also under the scope. Usually, the most differentiated tumors show only poor uptake of the FDG as they have a weak metabolic and proliferative activity. In the assessment of endocrine tumors, FDG-PET should be used only after most specific nuclear examinations been performed. (author)

  12. Detection of Unknown Primary Tumors Using Whole Body FDG PET

    ZHAOJun; LINXiangtong; GUANYihui; ZUOChuantao; HUAFengchun; SHENGXiaofang; WANGYang

    2003-01-01

    Objective: To assess the usefulness of 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) in locating occult primary lesions. Methods: 50 patients with varying hetero-geneous metastases of unknown primary origin were referred for FDG PET. The locations of the known metastatic tumor manifestations were distributed as follows: cervical lymph nodes metastases (n=18),skeletal metastases (n=15), cerebral metastases (n=12), others (n=5). All patients underwent whole body 18F-FDG PET imaging. The images were interpreted by visual inspection and semi-quantitative analysis(standardized uptake value, SUV). The patients had undergone conventional imaging within 2 weeks of FDG PET. Surgical, clinical and histopathologic findings were used to assess the performance of FDG PET.Results: FDG PET was able to detect the location of the primary tumor in 32/50 patients (64%). The primary tumors were proved by histopathologic results, and located in the lungs (n=17), the nasopharynx(n=9), the breast (n=2), the ovary (n=l), the colon(n=l), the prostate(n=l),the thyroid (n=l). FDG PET were proved false positive in 2 patients (4%), and the suspicious primary tumors were in uterus and colon respectively. During the clinical follow-up of 2 to 26 months, the primary tumor was found in only 2 patients ( prostate cancer, gastric cancer). Conclusion: PET imaging allows identification of the primary site and metastatic lesions(including bone and soft tissue metastases) at a single examination.Whole body lSF-FDG PET allows effective localization of the unknown primary site of origin and can contribute substantially to patient care.

  13. Lung tumor segmentation in PET images using graph cuts.

    Ballangan, Cherry; Wang, Xiuying; Fulham, Michael; Eberl, Stefan; Feng, David Dagan

    2013-03-01

    The aim of segmentation of tumor regions in positron emission tomography (PET) is to provide more accurate measurements of tumor size and extension into adjacent structures, than is possible with visual assessment alone and hence improve patient management decisions. We propose a segmentation energy function for the graph cuts technique to improve lung tumor segmentation with PET. Our segmentation energy is based on an analysis of the tumor voxels in PET images combined with a standardized uptake value (SUV) cost function and a monotonic downhill SUV feature. The monotonic downhill feature avoids segmentation leakage into surrounding tissues with similar or higher PET tracer uptake than the tumor and the SUV cost function improves the boundary definition and also addresses situations where the lung tumor is heterogeneous. We evaluated the method in 42 clinical PET volumes from patients with non-small cell lung cancer (NSCLC). Our method improves segmentation and performs better than region growing approaches, the watershed technique, fuzzy-c-means, region-based active contour and tumor customized downhill. PMID:23146420

  14. PET/FDG EB GastroIntestinal Stromal Tumors (GIST)

    Objectives: Review the results of PET / FDG in patients diagnosed with GIST, to establish whether there is active tumor requiring treatment with imatinib or to evaluate the response to it; Imatinib is a tyrosine kinase inhibitor which in turn, by a mutation of a proto-oncogene leads to uncontrolled cell proliferation. Methods: Practical PET / CT from the vertex to the middle third of the thighs, 90 minutes after IV administration of FDG (0.42 mCi / Kgrm) with Discovery LS PET / CT GE

  15. FDG PET/CT imaging of lung tumor

    PET/CT imaging combines PET for functional information and CT for morphological information in a single examination, and has shown how the initial staging with lung cancer. [18F]fluoro-deoxy-glucose (FDG) PET/CT imaging has a higher diagnostic accuracy for lung cancer except so-called bronchioloalveolar carcinoma and acute inflammatory lesion such as tuberculosis, pneumonia etc, compared with the conventional diagnostic modalities. FDG PET/CT imaging can demonstrate unexpected sites of mediastinal lymph node metastases (N factor), distant metastases (M factor) in initial staging and influence treatment plans for lung cancer. Furthermore, the grade of FDG uptake on PET/CT predicts prognosis of lung cancer and evaluates tumor response to treatment. Recurrences or metastases of lung cancer, and pleural disease can be detected correctly on FDG PET/CT. It is important that interpreting physicians understand the role of FDG PET/CT in staging, assessing of treatment and observing after therapy on the multidisciplinary managements of lung cancer. The clinical applications of PET/CT are still evolving, and future researches will determine the precise role that combined metabolic and morphological imaging has to play in the management of patients with lung cancer. (author)

  16. PET examination in intracranial tumor diagnosis of a cat

    This paper shows the significance of the Positron Emission Tomography (PET) in the veterinary medication through a case study of a cat brain tumor. A castrated male cat with bilateral mydriasis and blindness arrived at the veterinary clinic. After physical, laboratory and neurological investigations other sickness was ruled out and the inkling of the intracranial lesion had come to light. Brain tumor seemed the most likely to cause the illness because other symptoms appeared (for example: anorexia, depression) and they progrediated fast. PET examination, using 18F-FDG isotope, was performed to confirm the possible causes of the cat's symptoms

  17. PET examination in intracranial tumor diagnosis of a cat

    Angyal, G.; Csepura, G.; Balkay, L.; Galuska, L.; Molnár, J.; Valastyán, I.

    2008-12-01

    This paper shows the significance of the Positron Emission Tomography (PET) in the veterinary medication through a case study of a cat brain tumor. A castrated male cat with bilateral mydriasis and blindness arrived at the veterinary clinic. After physical, laboratory and neurological investigations other sickness was ruled out and the inkling of the intracranial lesion had come to light. Brain tumor seemed the most likely to cause the illness because other symptoms appeared (for example: anorexia, depression) and they progrediated fast. PET examination, using 18F-FDG isotope, was performed to confirm the possible causes of the cat's symptoms

  18. Utility of C-11 Choline PET for brain tumors

    The purpose of the present study was to assess the clinical potential of methyl-11C choline (C-11 choline) in brain tumors. The results of magnetic resonance (MR) imaging in 23 patients suspected of having brain tumors were then compared to the results of C-11 choline and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET). PET with C-11 choline and FDG, in addition to gadolinium-enhanced MR, were performed in these patients. A pathological diagnosis was made for each patient by open surgery. The standardized uptake values (SUVs) of brain tumors and the tumor-to-white matter count (T/W) ratios were determined. The degree of C-11 choline accumulation noted in PET images was compared to the gadolinium-enhanced areas of MR images. The mean T/W ratio of high-grade gliomas was found to be higher than that of low-grade gliomas. This difference was statistically significant (mean±SD: 8.7±6.2, n=9 versus 1.5±0.7 respectively, n=5, p<0.03) when data pertaining to the prominent uptake of C-11 choline by a patient with a pilocytic astrocytoma was excluded. C-11 choline PET failed to detect non-neoplastic lesions in two patients. Areas of C-11 choline accumulation in PET scans were longer than areas visualized by contrast enhancement on MR images in five cases involving high-grade gliomas. C-11 choline PET differentiated between low-grade gliomas and high-grade gliomas, but did not differentiate between low-grade gliomas and non-neoplasms. A combination of C-11 choline PET and MR imaging may provide investigators with accurate means to identify high-grade gliomas. (author)

  19. Utility of C-11 Choline PET for brain tumors

    Ohtani, Toshiyuki; Hashiba, Yasuhiro; Tosaka, Masahiko; Fujimaki, Hiroya; Sasaki, Tomio; Oriuchi, Noboru [Gunma Univ., Maebashi (Japan). School of Medicine; Inoue, Tomio [Yokohama City Univ. (Japan). School of Medicine

    2002-03-01

    The purpose of the present study was to assess the clinical potential of methyl-{sup 11}C choline (C-11 choline) in brain tumors. The results of magnetic resonance (MR) imaging in 23 patients suspected of having brain tumors were then compared to the results of C-11 choline and {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET). PET with C-11 choline and FDG, in addition to gadolinium-enhanced MR, were performed in these patients. A pathological diagnosis was made for each patient by open surgery. The standardized uptake values (SUVs) of brain tumors and the tumor-to-white matter count (T/W) ratios were determined. The degree of C-11 choline accumulation noted in PET images was compared to the gadolinium-enhanced areas of MR images. The mean T/W ratio of high-grade gliomas was found to be higher than that of low-grade gliomas. This difference was statistically significant (mean{+-}SD: 8.7{+-}6.2, n=9 versus 1.5{+-}0.7 respectively, n=5, p<0.03) when data pertaining to the prominent uptake of C-11 choline by a patient with a pilocytic astrocytoma was excluded. C-11 choline PET failed to detect non-neoplastic lesions in two patients. Areas of C-11 choline accumulation in PET scans were longer than areas visualized by contrast enhancement on MR images in five cases involving high-grade gliomas. C-11 choline PET differentiated between low-grade gliomas and high-grade gliomas, but did not differentiate between low-grade gliomas and non-neoplasms. A combination of C-11 choline PET and MR imaging may provide investigators with accurate means to identify high-grade gliomas. (author)

  20. A phantom study of tumor contouring on PET imaging

    Objective: To explore an algorithm to define the threshold value for tumor contouring on 18F-fluorodeoxyglucose (FDG) PET imaging. Methods: A National Electrical Manufacturing Association (NEMA)NU 2 1994 PET phantom with 5 spheres of different diameters were filled with 18F-FDG. Seven different sphere-to-background ratios were obtained and the phantom was scanned by Discovery LS 4. For each sphere-to-background ratio, the maximum standardized uptake value (SUVmax) of each sphere, the SUV of the border of each sphere (SUVborder), the mean SUV of a 1 cm region of background (SUVbg) and the diameter (D) of each sphere were measured. SPSS 13.0 software was used for curve fitting and regression analysis to obtain the threshold algorithm. The calculated thresholds were applied to delineate 29 pathologically confirmed lung cancer lesions on PET images and the obtained volumes were compared with the volumes contoured on CT images in lung window. Results: The algorithm for defining contour threshold is TH% = 33.1% + 46.8% SUVbg/SUVmax + 13.9%/D (r = 0.994) by phantom studies. For 29 lung cancer lesions, the average gross tumor volumes (GTV) delineated on PET and CT are (7.36±1.62) ml and (8.31±2.05) ml, respectively (t = -1.26, P>0.05). Conclusion: The proposed threshold algorithm for tumor contouring on PET image could provide comparable GTV with CT. (authors)

  1. Choline PET for Monitoring Early Tumor Response to Photodynamic Therapy

    Fei, Baowei; Wang, Hesheng; Wu, Chunying; Chiu, Song-mao

    2009-01-01

    Photodynamic therapy (PDT) is a relatively new therapy that has shown promise for treating various cancers in both preclinical and clinical studies. The present study evaluated the potential use of PET with radiolabeled choline to monitor early tumor response to PDT in animal models.

  2. 18F-FDG PET/MRI fusion in characterizing pancreatic tumors. Comparison to PET/CT

    The objective of this study was to demonstrate that positron emission tomography (PET)/magnetic resonance imaging (MRI) fusion was feasible in characterizing pancreatic tumors (PTs), comparing MRI and computed tomography (CT) as mapping images for fusion with PET as well as fused PET/MRI and PET/CT. We retrospectively reviewed 47 sets of 18F-fluorodeoxyglucose (18F-FDG) PET/CT and MRI examinations to evaluate suspected or known pancreatic cancer. To assess the ability of mapping images for fusion with PET, CT (of PET/CT), T1- and T2-weighted (w) MR images (all non-contrast) were graded regarding the visibility of PT (5-point confidence scale). Fused PET/CT, PET/T1-w or T2-w MR images of the upper abdomen were evaluated to determine whether mapping images provided additional diagnostic information to PET alone (3-point scale). The overall quality of PET/CT or PET/MRI sets in diagnosis was also assessed (3-point scale). These PET/MRI-related scores were compared to PET/CT-related scores and the accuracy in characterizing PTs was compared. Forty-three PTs were visualized on CT or MRI, including 30 with abnormal FDG uptake and 13 without. The confidence score for the visibility of PT was significantly higher on T1-w MRI than CT. The scores for additional diagnostic information to PET and overall quality of each image set in diagnosis were significantly higher on the PET/T1-w MRI set than the PET/CT set. The diagnostic accuracy was higher on PET/T1-w or PET/T2-w MRI (93.0 and 90.7%, respectively) than PET/CT (88.4%), but statistical significance was not obtained. PET/MRI fusion, especially PET with T1-w MRI, was demonstrated to be superior to PET/CT in characterizing PTs, offering better mapping and fusion image quality. (author)

  3. Early Tumor Response to Hsp90 Therapy Using HER2 PET: Comparison with 18F-FDG PET

    Smith-Jones, Peter M.; Solit, David; Afroze, Farzana; Rosen, Neal; Larson, Steven M.

    2006-01-01

    We compared 68Ga-DOTA-F(ab′)2-herceptin (DOTA is 1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid [HER2 PET]) and 18F-FDG PET for imaging of tumor response to the heat shock protein 90 (Hsp90) inhibitor 17-allylamino-17-demethoxygeldanamycin (17AAG).

  4. PET and PET/CT in tumour of undetermined origin; PET y PET/CT en tumor de origen indeterminado

    Garcia O, J.R. [Nuclear Medicine and Molecular Imaging, PET/CT, Centro Medico ABC, Mexico D.F. (Mexico)

    2007-07-01

    In this presentation the following conclusions were obtained regarding the use of PET and PET/CT in patient with cancer of unknown primary: 1. Detection of the primary one in 1/3 at 1/2 of patient. 2. It detects metastases in other places in 50%. 3. It changes the initial therapy planned in 1/3 at 1/2 of patient. 4. Useful in initial phases of protocol study to limit the other procedures. After standard evaluation. Before advanced protocol. 5. PET/CT study increases the % of primary detection, although in a non significant way vs. PET. 6. They are required more studies to value their utility to a more objective manner. (Author)

  5. A pretargeting system for tumor PET imaging and radioimmunotherapy

    Françoise eKraeber-Bodéré

    2015-03-01

    Full Text Available Labeled antibodies, as well as their fragments and antibody-derived recombinant constructs, have long been proposed as general vectors to target radionuclides to tumor lesions for imaging and therapy. They have indeed shown promise in both imaging and therapeutic applications, but they have not fulfilled the original expectations of achieving sufficient image contrast for tumor detection or sufficient radiation dose delivered to tumors for therapy. Pretargeting was originally developed for tumor immunoscintigraphy. It was assumed that directly-radiolabled antibodies could be replaced by an unlabeled immunoconjugate capable of binding both a tumor-specific antigen and a small molecular weight molecule. The small molecular weight molecule would carry the radioactive payload and would be injected after the bispecific immunoconjugate. It has been demonstrated that this approach does allow for both antibody-specific recognition and fast clearance of the radioactive molecule, thus resulting in improved tumor-to-normal tissue contrast ratios. It was subsequently shown that pretargeting also held promise for tumor therapy, translating improved tumor-to-normal tissue contrast ratios into more specific delivery of absorbed radiation doses. Many technical approaches have been proposed to implement pretargeting, and two have been extensively documented. One is based on the avidin-biotin system, and the other on bispecific antibodies binding a tumor-specific antigen and a hapten. Both have been studied in preclinical models, as well as in several clinical studies, and have shown improved targeting efficiency. This article reviews the historical and recent preclinical and clinical advances in the use of bispecific-antibody-based pretargeting for radioimmunodetection and radioimmunotherapy of cancer. The results of recent evaluation of pretargeting in PET imaging also are discussed.

  6. Assessment of Chemotherapy Response Using FDG-PET in Pediatric Bone Tumors: A Single Institution Experience

    Kim, Dong Hwan; Kim, Seung Yeon; Lee, Hyeon Jeong; Song, Bong Sup; Kim, Dong Ho; Cho, Joong Bum; Lim, Jung Sub; Lee, Jun Ah

    2011-01-01

    Purpose Response to neo-adjuvant chemotherapy is an important prognostic factor for osteosarcoma (OS) and the Ewing sarcoma family of tumors (ESFT). [F-18]-fluorodeoxy-D-glucose (FDG)-positron emission tomography (PET) is a non-invasive imaging modality that predicts histologic response to chemotherapy of various malignancies; however, limited data exist about the usefulness of FDG-PET in predicting the histologic response of pediatric bone tumors to chemotherapy. We analyzed the FDG-PET imag...

  7. PET-CT Fusion in Radiation Management of Patients with Anorectal Tumors

    Purpose: To compare computed tomography (CT) with positron emission tomography-CT (PET-CT) scans with respect to anorectal tumor volumes, correlation in overlap, and influence on radiation treatment fields and patient care. Patients and Methods: From March to November 2003, 20 patients with rectal cancer and 3 patients with anal cancer were treated with preoperative or definitive chemoradiation, respectively. Computed tomography simulation data generated a CT gross tumor volume (CT-GTV) and CT planning target volume (CT-PTV) and 18F-fluoro-2-deoxy-glucose PET (FDG-PET) created a PET-GTV and PET-PTV. The PET-CT and CT images were fused using manual coregistration. Patients were treated with three-dimensional conformal therapy to traditional doses. The PET, CT, and overlap volumes (OVs) were measured in cubic centimeters. Results: Mean PET-GTV was smaller than the mean CT-GTV (91.7 vs. 99.6 cm3). The mean OV was 46.7%. As tumor volume increased, PET and CT OV correlated significantly (p 10 and the posttreatment PET standardized uptake value was <6, 100% achieved pathologic downstaging (p = 0.047). Conclusions: Variation in volume was significant, with 17% and 26% of patients requiring a change in treatment fields and patient management, respectively. Positron emission tomography can change the management for anorectal tumors by early detection of metastatic disease or disease outside standard radiation fields

  8. Analysis of 18F-FDG PET mapping in malignant tumor patients with depression by SPM

    Objective: To investigate brain 18F-fluorodeoxyglucose (FDG) PET mapping in malignant tumor patients with depressive emotion. Methods: 18F-FDG PET imaging was performed in 21 malignant tumor patients (tumor group) and 21 healthy controls (control group). All were evaluated by self-rating depression scale (SDS)and 24 questions Hamilton rating scale for depression (HAMD). Results: (1) The standard total score of SDS and HAMD of the tumor group were higher than those of the control group (P18F-FDG PET imagings. The abnormalities of glucose metabolism might be related to their depressive emotion. (authors)

  9. Multimodal imaging utilising integrated MR-PET for human brain tumour assessment

    Neuner, Irene [Institute of Neuroscience and Medicine 4, INM 4, Juelich (Germany); RWTH Aachen University, Department of Psychiatry, Psychotherapy and Psychosomatics, Aachen (Germany); JARA-BRAIN-Translational Medicine, Aachen (Germany); Kaffanke, Joachim B. [Institute of Neuroscience and Medicine 4, INM 4, Juelich (Germany); MR-Transfer e.K., Wuppertal (Germany); Langen, Karl-Josef; Kops, Elena Rota; Tellmann, Lutz; Stoffels, Gabriele; Weirich, Christoph; Filss, Christian; Scheins, Juergen; Herzog, Hans [Institute of Neuroscience and Medicine 4, INM 4, Juelich (Germany); Shah, N. Jon [Institute of Neuroscience and Medicine 4, INM 4, Juelich (Germany); RWTH Aachen University, Department of Neurology, Aachen (Germany); JARA-BRAIN-Translational Medicine, Aachen (Germany)

    2012-12-15

    The development of integrated magnetic resonance (MR)-positron emission tomography (PET) hybrid imaging opens up new horizons for imaging in neuro-oncology. In cerebral gliomas the definition of tumour extent may be difficult to ascertain using standard MR imaging (MRI) only. The differentiation of post-therapeutic scar tissue, tumour rests and tumour recurrence is challenging. The relationship to structures such as the pyramidal tract to the tumour mass influences the therapeutic neurosurgical approach. The diagnostic information may be enriched by sophisticated MR techniques such as diffusion tensor imaging (DTI), multiple-volume proton MR spectroscopic imaging (MRSI) and functional MRI (fMRI). Metabolic imaging with PET, especially using amino acid tracers such as {sup 18}F-fluoroethyl-l-tyrosine (FET) or {sup 11}C-l-methionine (MET) will indicate tumour extent and response to treatment. The new technologies comprising MR-PET hybrid systems have the advantage of providing comprehensive answers by a one-stop-job of 40-50 min. The combined approach provides data of different modalities using the same iso-centre, resulting in optimal spatial and temporal realignment. All images are acquired exactly under the same physiological conditions. We describe the imaging protocol in detail and provide patient examples for the different imaging modalities such as FET-PET, standard structural imaging (T1-weighted, T2-weighted, T1-weighted contrast agent enhanced), DTI, MRSI and fMRI. (orig.)

  10. Multimodal imaging utilising integrated MR-PET for human brain tumour assessment

    The development of integrated magnetic resonance (MR)-positron emission tomography (PET) hybrid imaging opens up new horizons for imaging in neuro-oncology. In cerebral gliomas the definition of tumour extent may be difficult to ascertain using standard MR imaging (MRI) only. The differentiation of post-therapeutic scar tissue, tumour rests and tumour recurrence is challenging. The relationship to structures such as the pyramidal tract to the tumour mass influences the therapeutic neurosurgical approach. The diagnostic information may be enriched by sophisticated MR techniques such as diffusion tensor imaging (DTI), multiple-volume proton MR spectroscopic imaging (MRSI) and functional MRI (fMRI). Metabolic imaging with PET, especially using amino acid tracers such as 18F-fluoroethyl-l-tyrosine (FET) or 11C-l-methionine (MET) will indicate tumour extent and response to treatment. The new technologies comprising MR-PET hybrid systems have the advantage of providing comprehensive answers by a one-stop-job of 40-50 min. The combined approach provides data of different modalities using the same iso-centre, resulting in optimal spatial and temporal realignment. All images are acquired exactly under the same physiological conditions. We describe the imaging protocol in detail and provide patient examples for the different imaging modalities such as FET-PET, standard structural imaging (T1-weighted, T2-weighted, T1-weighted contrast agent enhanced), DTI, MRSI and fMRI. (orig.)

  11. Diagnostic value of PET/CT for the staging and restaging of pediatric tumors

    The objective of this retrospective study was to compare the diagnostic value of 2-[18F]fluoro-2-deoxy-d-glucose positron emission tomography (18F-FDG PET)/CT versus 18F-FDG PET and CT alone for staging and restaging of pediatric solid tumors. Forty-three children and adolescents (19 females and 24 males; mean age, 15.2 years; age range, 6-20 years) with osteosarcoma (n 1), squamous cell carcinoma (n = 1), synovial sarcoma (n = 2), germ cell tumor (n = 2), neuroblastoma (n = 2), desmoid tumor (n = 2), melanoma (n = 3), rhabdomyosarcoma (n = 5), Hodgkin's lymphoma (n = 7), non-Hodgkin-lymphoma (n 9), and Ewing's sarcoma (n = 9) who had undergone 18F-FDG PET/CT imaging for primary staging or follow-up of metastases were included in this study. The presence, location, and size of primary tumors was determined separately for PET/CT, PET, and CT by two experienced reviewers. The diagnosis of the primary tumor was confirmed by histopathology. The presence or absence of metastases was confirmed by histopathology (n = 62) or clinical and imaging follow-up (n 238). The sensitivities for the detection of solid primary tumors using integrated 18F-FDG PET/CT (95%), 18F-FDG PET alone (73%), and CT alone (93%) were not significantly different (p > 0.05). Seventeen patients showed a total of 153 distant metastases. Integrated PET/CT had a significantly higher sensitivity for the detection of these metastases (91%) than PET alone (37%; p 0.05). When lesions with a diameter of less than 0.5 cm were excluded, PET/CT (89%) showed a significantly higher specificity compared to PET (45%; p 18F-FDG PET/CT, 18F-FDG PET alone, and CT alone were diagnostically correct in 83%, 61%, and 42%. A sub-analysis focusing on the ability of PET/CT, PET, and CT to detect osseous metastases showed no statistically significant difference between the three imaging modalities (p > 0.05). Our study showed a significantly increased sensitivity of PET/CT over that of PET for the detection of distant

  12. Evaluation of thymic tumors with 18F-FDG PET-CT - A pictorial review

    Sharma, Punit; Singhal, Abhinav; Bal, Chandrasekhar; Malhotra, Arun; Kumar, Rakesh [Dept. of Nuclear Medicine, All India Inst. of Medical Sciences, New Delhi (India)], e-mail: rkphulia@yahoo.com; Kumar, Arvind [Dept. of Surgical Disciplines, All India Inst. of Medical Sciences, New Delhi (India)

    2013-02-15

    Thymic tumors represent a broad spectrum of neoplastic disorders and pose considerable diagnostic difficulties. A non-invasive imaging study to determine the nature of thymic lesions can have significant impact on management of such tumors. 18F-flurorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) has shown promising results in characterization of thymic tumors. The objective of this article is to provide an illustrative tutorial highlighting the clinical utility of 18F-FDG PET-CT imaging in patients with thymic tumors. We have pictorially depicted the 18F-FDG PET-CT salient imaging characteristics of various thymic tumors, both epithelial and non-epithelial. Also discussed is the dynamic physiology of thymus gland which is to be kept in mind when evaluating thymic pathology on 18F-FDG PET-CT, as it can lead to interpretative pitfalls.

  13. Recurrent giant cell tumor of foot detected by F18-FDG PET/CT

    Detection of recurrence of tumors with conventional imaging like computed tomography (CT) and magnetic resonance imaging (MRI) can be difficult because of distorted anatomy and implants in situ. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) has been shown to be very useful in detection of recurrent tumors with higher accuracy than conventional imaging method. Giant cell tumors of foot though rare have high recurrence potential after initial curative treatment. However, currently there is no literature addressing the role of F-18 FDG PET/CT in evaluation of these tumors. We report a case of post excisional recurrent giant cell tumor of foot diagnosed on F-18 FDG PET/CT. In addition, to detection of recurrence F-18 FDG PET/CT also aided in accurate management of the patient. (author)

  14. Evaluation of thymic tumors with 18F-FDG PET-CT - A pictorial review

    Thymic tumors represent a broad spectrum of neoplastic disorders and pose considerable diagnostic difficulties. A non-invasive imaging study to determine the nature of thymic lesions can have significant impact on management of such tumors. 18F-flurorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) has shown promising results in characterization of thymic tumors. The objective of this article is to provide an illustrative tutorial highlighting the clinical utility of 18F-FDG PET-CT imaging in patients with thymic tumors. We have pictorially depicted the 18F-FDG PET-CT salient imaging characteristics of various thymic tumors, both epithelial and non-epithelial. Also discussed is the dynamic physiology of thymus gland which is to be kept in mind when evaluating thymic pathology on 18F-FDG PET-CT, as it can lead to interpretative pitfalls

  15. Clinical value of PET/CT for the management of malignant tumors

    Objective: To investigate the clinical value of PET/CT for the management of malignant tumors. Methods: 96 patients (68 male, 28 female, mean age 61.7, ranged 26-89 years old). All are confirmed by pathology or clinic ally except brain tumor and all were not treated. PET/CT imaging was performed using GE Discovery LS PET/CT. Radiotherapy target definition: gross target volume (GTV) was defined using PET/CT fusion imaging. All data were analyzed with SPSS 10.0. Results: 1) Of 96 patients, PET/CT detection sensitivity was 97.92%. The overall tumor staging was changed in 44(45.83%) patients and the rates of metastasis to the lymph nodes and other organs were increased 37.50% and 23.96%, respectively. 2) The therapy regimen was changed in 35(36.46%) patients after PET/CT imaging. 3) The size, boundary and surrounding tissue of the tumor were clearly delineated in the fusion image. Hence it was possible for localization of biological target volume in radiotherapy and also for assessment of the resected extent for surgery. Conclusion: PET/CT plays an important role in early diagnosis, accurate staging and management of tumor patients, especially as a guide to localization of the target volume in radiotherapy and assessment of the resected tumor extent during operation. (authors)

  16. FDG-PET probe-guided surgery for recurrent retroperitoneal testicular tumor recurrences

    Jong, J.S. de; van Ginkel, R.J.; Slart, R.H.J.A.; Lemstra, C.L.; Paans, A.M.J.; Mulder, N. H.; Hoekstra, H.J.

    2010-01-01

    Abstract Aim Tumor marker based recurrences of previously treated testicular cancer are generally detected with CT-scan. They sometimes cannot be visualized with conventional morphologic imaging. FDG-PET has the ability to detect these recurrences. PET probe-guided surgery, may facilitate the extent of surgery and optimize the surgical resection. Methods Three patient with resectable 2nd or 3rd recurrent testicular cancer based on elevated tumor mar...

  17. Benign and malignant neurogenic tumors of nerve sheath origin on FDG PET

    The differentiation between benign and malignant nerve sheath tumors is difficult based on conventional radiological imaging. This study was undertaken to investigate the value of FDG PET in distinguishing benign from malignant neurogenic tumors of nerve sheath origin. We performed a retrospective review of the medical record to select patients with nerve sheath tumors who had underdone FDG PET imaging. Fifteen patients (7F: 8M) with benign or malignant nerve sheath tumors were included in this study. Of the 15 patients, 9 were diagnosed with the known neurofibromatosis type I. A total of 19 nerve sheath tumors were included from the 15 patients. All patients had undergone FDG PET to evaluate for malignant potential of the known lesions. Images of FDG PET were semi-quantitatively analyzed and a region of interest (ROI) was placed over the area of the maximum FDG uptake and an average standardized uptake value was taken for final analysis. There were 5 malignant peripheral nerve sheath tumors, 5 schwannomas, and 9 neurofibromas. The mean SUV was 2 (ranged from 1.6 to 3.3) for schwannomas, 1.3 (0.7 to 2.5) for neurofibromas, and 8.4 (4.6 to 12.2) for malignant peripheral nerve sheath tumors. Of 14 benign tumors, all except one schwannoma showed a SUV less than 3. When a cutoff SUV of 4 was used to differentiate the nerve sheath tumors, all tumors were correctly classified as benign or malignant, respectively. Among the 9 patients diagnosed with neurofibromatosis type I. 4 had malignant peripheral nerve sheath tumors and FDG PET accurately detected all the 4 lesions with malignant transformation. According to our results, FDG PET seems to have a great potential for accurately characterizing benign versus malignant nerve sheath tumors. It appears to be extremely useful for patients with neurofibromatosis to localize the lesion with malignant transformation

  18. Benign and malignant neurogenic tumors of nerve sheath origin on FDG PET

    Yun, M. J.; Go, D. H.; Yoo, Y. H.; Shin, K. H.; Lee, J. D [College of Medicine, Yonsei University, Seoul (Korea, Republic of)

    2004-07-01

    The differentiation between benign and malignant nerve sheath tumors is difficult based on conventional radiological imaging. This study was undertaken to investigate the value of FDG PET in distinguishing benign from malignant neurogenic tumors of nerve sheath origin. We performed a retrospective review of the medical record to select patients with nerve sheath tumors who had underdone FDG PET imaging. Fifteen patients (7F: 8M) with benign or malignant nerve sheath tumors were included in this study. Of the 15 patients, 9 were diagnosed with the known neurofibromatosis type I. A total of 19 nerve sheath tumors were included from the 15 patients. All patients had undergone FDG PET to evaluate for malignant potential of the known lesions. Images of FDG PET were semi-quantitatively analyzed and a region of interest (ROI) was placed over the area of the maximum FDG uptake and an average standardized uptake value was taken for final analysis. There were 5 malignant peripheral nerve sheath tumors, 5 schwannomas, and 9 neurofibromas. The mean SUV was 2 (ranged from 1.6 to 3.3) for schwannomas, 1.3 (0.7 to 2.5) for neurofibromas, and 8.4 (4.6 to 12.2) for malignant peripheral nerve sheath tumors. Of 14 benign tumors, all except one schwannoma showed a SUV less than 3. When a cutoff SUV of 4 was used to differentiate the nerve sheath tumors, all tumors were correctly classified as benign or malignant, respectively. Among the 9 patients diagnosed with neurofibromatosis type I. 4 had malignant peripheral nerve sheath tumors and FDG PET accurately detected all the 4 lesions with malignant transformation. According to our results, FDG PET seems to have a great potential for accurately characterizing benign versus malignant nerve sheath tumors. It appears to be extremely useful for patients with neurofibromatosis to localize the lesion with malignant transformation.

  19. Automatic delineation of tumor volumes by co-segmentation of combined PET/MR data

    Combined PET/MRI may be highly beneficial for radiotherapy treatment planning in terms of tumor delineation and characterization. To standardize tumor volume delineation, an automatic algorithm for the co-segmentation of head and neck (HN) tumors based on PET/MR data was developed. Ten HN patient datasets acquired in a combined PET/MR system were available for this study. The proposed algorithm uses both the anatomical T2-weighted MR and FDG-PET data. For both imaging modalities tumor probability maps were derived, assigning each voxel a probability of being cancerous based on its signal intensity. A combination of these maps was subsequently segmented using a threshold level set algorithm. To validate the method, tumor delineations from three radiation oncologists were available. Inter-observer variabilities and variabilities between the algorithm and each observer were quantified by means of the Dice similarity index and a distance measure. Inter-observer variabilities and variabilities between observers and algorithm were found to be comparable, suggesting that the proposed algorithm is adequate for PET/MR co-segmentation. Moreover, taking into account combined PET/MR data resulted in more consistent tumor delineations compared to MR information only. (paper)

  20. Role of 18F - DOPA PET/CT in evaluation of patients with neuroendocrine tumors (NETs)

    Full text: NETs are heterogeneous group of tumors which take up amino acids, transform them into biogenic amines and store the amines in vesicles, this forms the basis of uptake of 18F-DOPA in these tumors. These tumors can be small and situated almost throughout the body and may also present as advanced disease with multiple metastatic sites. Like in management of any other tumor it is imperative to stage the status of disease in NETs for the effective management of these patients and 18F-DOPA PET/CT is one such imaging modality used in the evaluation of neuroendocrine tumors (NETs). Here is our initial experience using 18F-DOPA PET/CT imaging in these patients. Twenty-seven patients with NETs (carcinoids, medullary thyroid carcinomas, phaeochromocytomas Insulinoma) were prospectively enrolled and scheduled for 18F-DOPA PET/CT. Wherever possible, tissue diagnosis was attempted. Results obtained were compared with other conventional diagnostic procedures (mainly 18F-FDG PET/CT, and 68Ga-DOTANOC PET/CT, and with ultrasound, CT, etc) and with follow-up. 18F-DOPA PET/CT identified 17/24 positive cases in either the primary/metastatic/recurrent tumor. In case of Insulinoma 18F-DOPA was found to be most superior than other imaging modalities in localizing the disease and staging of disease

  1. Desmoid Tumor Showing Intense Uptake on 68Ga PSMA-HBED-CC PET/CT.

    Kanthan, Gowri L; Hsiao, Edward; Kneebone, Andrew; Eade, Thomas; Schembri, Geoffrey Paul

    2016-06-01

    Ga-PSMA PET/CT is a new imaging technique that is highly sensitive to metastatic prostate cancer lesions compared with other conventional imaging modalities. We report a case of a 77-year-old man with newly diagnosed prostate carcinoma who had a PSMA PET/CT scan for staging of his disease. An intensely PSMA-avid right pelvic mass was identified abutting the cecum and terminal ileum. Surgical removal and histopathologic examination of this lesion revealed the diagnosis of a desmoid tumor. It is important to be aware that many tumors other than prostate carcinoma may also show avid uptake on PSMA PET/CT scan. PMID:26909712

  2. Automatic co-segmentation of lung tumor based on random forest in PET-CT images

    Jiang, Xueqing; Xiang, Dehui; Zhang, Bin; Zhu, Weifang; Shi, Fei; Chen, Xinjian

    2016-03-01

    In this paper, a fully automatic method is proposed to segment the lung tumor in clinical 3D PET-CT images. The proposed method effectively combines PET and CT information to make full use of the high contrast of PET images and superior spatial resolution of CT images. Our approach consists of three main parts: (1) initial segmentation, in which spines are removed in CT images and initial connected regions achieved by thresholding based segmentation in PET images; (2) coarse segmentation, in which monotonic downhill function is applied to rule out structures which have similar standardized uptake values (SUV) to the lung tumor but do not satisfy a monotonic property in PET images; (3) fine segmentation, random forests method is applied to accurately segment the lung tumor by extracting effective features from PET and CT images simultaneously. We validated our algorithm on a dataset which consists of 24 3D PET-CT images from different patients with non-small cell lung cancer (NSCLC). The average TPVF, FPVF and accuracy rate (ACC) were 83.65%, 0.05% and 99.93%, respectively. The correlation analysis shows our segmented lung tumor volumes has strong correlation ( average 0.985) with the ground truth 1 and ground truth 2 labeled by a clinical expert.

  3. The importance of PET/CT in the evaluation of patients with Ewing tumors

    Guimaraes, Julio Brandao; Rigo, Leticia; Lewin, Fabio; Emerick, Andre, E-mail: juliobrandaoguimaraes@hotmail.com [Hospital Sao Jose-Beneficincia Portuguesa de Sao Paulo, SP (Brazil)

    2015-05-15

    The effective evaluation for the treatment of patients with Ewing tumors depends on the accuracy in the determination of the primary tumor extent and the presence of metastatic disease. Currently, no universally accepted staging system is available to assess Ewing tumors. The present study aimed at discussing the use of PET/CT as a tool for staging, restaging and assessment of therapeutic response in patients with Ewing tumors. In spite of some limitations of PET/CT as compared with anatomical imaging methods, its relevance in the assessment of these patients is related to the capacity of the method to provide further physiological information, which often generates important clinical implications. Currently, the assessment of patients with Ewing tumor should comprise a study with PET/CT combined with other anatomical imaging modalities, such as radiography, computed tomography and magnetic resonance imaging. (author)

  4. Dynamic respiratory gated 18FDG-PET of lung tumors - a feasibility study

    Background. 18FDG-PET/CT imaging is well established for diagnosis and staging of lung tumors. However, more detailed information regarding the distribution of FDG within the tumor, also as a function of time after injection may be relevant. In this study we explore the feasibility of a combined dynamic and respiratory gated (DR) PET protocol. Material and methods. A DR FDG-PET protocol for a Siemens Biograph 16 PET/CT scanner was set up, allowing data acquisition from the time of FDG injection. Breath-hold (BH) respiratory gating was performed at four intervals over a total acquisition time of 50 minutes. Thus, the PET protocol provides both motion-free images and a spatiotemporal characterization of the glucose distribution in lung tumors. Software tools were developed in-house for tentative tumor segmentation and for extracting standard uptake values (SUVs) voxel by voxel, tumor volumes and SUV gradients in all directions. Results. Four pilot patients have been investigated with the DR PET protocol. The procedure was well tolerated by the patients. The BH images appeared sharper, and SUVmax/SUVmean was higher, compared to free breathing (FB) images. Also, SUV gradients in the periphery of the tumor in the BH images were in general greater than or equal to the gradients in the FB PET images. Conclusion. The DR FDG-PET protocol is feasible and the BH images have a superior quality compared to the FB images. The protocol may also provide information of relevance for radiotherapy planning and follow-up. A patient trial is needed for assessing the clinical value of the imaging protocol

  5. Assessment of Tumor Response to Therapy in Lymphoma Using 18F-FDG PET: Diagnostic Performance of 18F-FDG PET and Interval Likelihood Ratio

    In this paper, the authors intended to summarize briefly the features of lymphoma with regard to 18F-FDG PET for assessment of tumor response to therapy, to describe why assessment of treatment response should be performed, to review what method so far has been used in monitoring treatment response, to discuss what limitations of morphologic imaging criteria for assessing tumor response are, in compared with 18F-FDG PET, and to introduce recently proposed criteria for assessing tumor response in malignant lymphoma. And also the authors emphasize the need to understand the characteristics of diagnostic performance of 18F-FDG PET in several clinical settings in order to interpret 18F-FDG PET results appropriately, and to encourage the use of interval likelihood ratio to enhance clinical implications of test results which, in turns, allows referring physicians to understand the meaning of interpretation with easy. Until recently, treatment response has been assessed according to the morphologic criteria. Metabolic imaging with 18F-FDG PET was adopted to have important role for treatment assessment in IWC+PET criteria proposed recently by IHP. To accomplish this role, we should perform and interpret 18F-FDG PET according to IWC+PET criteria. It is important for referring physicians to understand the various limitations of 18F-FDG PET and pitfalls in PET interpretation, and to understand that clinical information are needed by nuclear medicine physicians to optimize the interpretation of 18F-FDG PET

  6. Diagnostic value of PET/CT for the staging and restaging of pediatric tumors

    Kleis, Margit [University of California (UCSF), Department of Radiology, San Francisco, CA (United States)]|[Technical University of Munich, Department of Radiology, Munich (Germany); Daldrup-Link, Heike; Lu, Ying; Schreck, Carole; Chu, Philip W.; Hawkins, Randall A.; Franc, Benjamin L. [University of California (UCSF), Department of Radiology, San Francisco, CA (United States); Matthay, Katherine [University of California, Department of Pediatrics, Division of Pediatric Hemato-Oncology, San Francisco, CA (United States); Goldsby, Robert [University of California, Department of Pediatric Oncology, San Francisco, CA (United States); Schuster, Tibor [Technical University of Munich, Department of Biostatistics and Epidemiology, Munich (Germany)

    2009-01-15

    The objective of this retrospective study was to compare the diagnostic value of 2-[{sup 18}F]fluoro-2-deoxy-d-glucose positron emission tomography ({sup 18}F-FDG PET)/CT versus {sup 18}F-FDG PET and CT alone for staging and restaging of pediatric solid tumors. Forty-three children and adolescents (19 females and 24 males; mean age, 15.2 years; age range, 6-20 years) with osteosarcoma (n = 1), squamous cell carcinoma (n = 1), synovial sarcoma (n = 2), germ cell tumor (n = 2), neuroblastoma (n = 2), desmoid tumor (n = 2), melanoma (n = 3), rhabdomyosarcoma (n = 5), Hodgkin's lymphoma (n = 7), non-Hodgkin-lymphoma (n = 9), and Ewing's sarcoma (n = 9) who had undergone {sup 18}F-FDG PET/CT imaging for primary staging or follow-up of metastases were included in this study. The presence, location, and size of primary tumors was determined separately for PET/CT, PET, and CT by two experienced reviewers. The diagnosis of the primary tumor was confirmed by histopathology. The presence or absence of metastases was confirmed by histopathology (n = 62) or clinical and imaging follow-up (n = 238). The sensitivities for the detection of solid primary tumors using integrated {sup 18}F-FDG PET/CT (95%), {sup 18}F-FDG PET alone (73%), and CT alone (93%) were not significantly different (p > 0.05). Seventeen patients showed a total of 153 distant metastases. Integrated PET/CT had a significantly higher sensitivity for the detection of these metastases (91%) than PET alone (37%; p < 0.05), but not CT alone (83%; p > 0.05). When lesions with a diameter of less than 0.5 cm were excluded, PET/CT (89%) showed a significantly higher specificity compared to PET (45%; p < 0.05) and CT (55%; p < 0.05). In a sub-analysis of pulmonary metastases, the values for sensitivity and specificity were 90%, 14%, 82% and 63%, 78%, 65%, respectively, for integrated PET/CT, stand-alone PET, and stand-alone CT. For the detection of regional lymph node metastases, {sup 18}F-FDG PET/CT, {sup 18}F

  7. Random walk and graph cut for co-segmentation of lung tumor on PET-CT images

    Ju, Wei; Xiang, Deihui; Zhang, Bin; Wang, Lirong; Kopriva, Ivica; Chen, Xinjian

    2015-01-01

    Accurate lung tumor delineation plays an important role in radiotherapy treatment planning. Since the lung tumor has poor boundary in positron emission tomography (PET) images and low contrast in computed tomography (CT) images, segmentation of tumor in the PET and CT images is a challenging task. In this paper, we effectively integrate the two modalities by making fully use of the superior contrast of PET images and superior spatial resolution of CT images. Random walk and graph cut method i...

  8. Discrimination of lung tumors on PET/CT images using registration method

    Positron Emission Tomography (PET) inspection have been performed to discover malignant tumor. However, it is difficult to discriminate benign tumors from malignant tumors, because the sugar metabolism is active on the inflammation of benign tumors as well as malignant tumors. In there cases, medical doctors take an image at regular intervals again to distinguish them. It is difficult to diagnosis lung tumor by observation, so the doctor does the comparable interpretation of radiogram. Then, we proposed a method to help doctor's comparison interpretation of radiogram using computers. We subtract between the early image and the delay image for the comparison interpretation of radiogram by computer, to make temporal subtraction image that emphasized the temporal change. Registration is important in the temporal difference image because correct difference processing cannot be done by the gap of the physique and the breath. However, the exact registration cannot be performed by the PET images because of their low resolution. The present study used the registration of the PET image is performed by doing the registration of the computed tomography image, and applying the deformation parameter to the PET image. After, we makes the temporal difference image of the PET image to distinguish it. (author)

  9. PET imaging in a longitudinal non-Hodgkin's lymphoma study: association with tumor volume

    Rossi, Maija; Jaervenpaeae, Ritva (Medical Imaging Centre, Dept. of Radiology, Tampere Univ. Hospital, Tampere (Finland)), email: maija.rossi@pshp.fi; Korkola, Pasi (Medical Imaging Centre, Dept. of Nuclear Medicine, Tampere Univ. Hospital, Tampere (Finland)); Pertovaara, Hannu (Dept. of Oncology, Tampere Univ. Hospital, Tampere (Finland)); Dastidar, Prasun; Soimakallio, Seppo (Medical Imaging Centre, Dept. of Radiology, Tampere Univ. Hospital, Tampere (Finland); Tampere Medical School, Tampere (Finland)); Wu, Xingchen (Medical Imaging Centre, Dept. of Radiology, Tampere Univ. Hospital, Tampere (Finland); Dept. of Oncology, Tampere Univ. Hospital, Tampere (Finland)); Eskola, Hannu (Medical Imaging Centre, Dept. of Radiology, Tampere Univ. Hospital, Tampere (Finland); Dept. of Biomedical Engineering, Tampere Univ. of Technology, Tampere (Finland)); Kellokumpu-Lehtinen, Pirkko-Liisa (Dept. of Oncology, Tampere Univ. Hospital, Tampere (Finland); Tampere Medical School, Tampere (Finland))

    2011-11-15

    Background. Computed tomography (CT) is generally used in the evaluation of the treatment response of non-Hodgkin's lymphoma (NHL) patients. Instead of morphological images, positron emission tomography (PET) shows metabolic information that is connected to tumor activity, cell proliferation rate, and, thus, prognosis. Purpose. To determine the prognostic value of PET for tumor volume reduction measured by CT and magnetic resonance imaging (MRI) along with clinical characteristics in NHL patients. Material and Methods. We imaged 21 B-cell type NHL patients using whole-body 18F-FDG-PET at the onset and the completion of treatment and at six-month follow-up. The maximum standardized uptake value (SUV{sub max}) was calculated. Morphological tumor volume calculations were assessed using both MRI and CT. Additionally, patients underwent thorough clinical examination including several laboratory tests. Results. A high SUV{sub max} was able to predict significant tumor volume reduction at the beginning of treatment, but the relation to pure tumor volume was poor. Conclusion. The SUV{sub max} values derived from FDG-PET seemed to correlate with volume changes but not with their absolute values or laboratory tests. Unlike MRI and CT, FDG-PET showed the disappearance of active tumors after treatment

  10. 6-L-(18)F-fluorodihydroxyphenylalanine PET in neuroendocrine tumors : Basic aspects and emerging clinical applications

    Jager, Pieter L.; Chirakal, Raman; Marriott, Christopher J.; Brouwers, Adrienne H.; Koopmans, Klaas Pieter; Gulenchyn, Karen Y.

    2008-01-01

    In recent years, 6-L-(18)F-fluorodihydroxyphenylalanine ((18)F-DOPA) PET has emerged as a new diagnostic tool for the imaging of neuroendocrine tumors. This application is based on the unique property of neuroendocrine tumors to produce and secrete various substances, a process that requires the upt

  11. (18)F-Fluorodeoxyglucose PET/Computed Tomography for Primary Brain Tumors

    Antonsen Segtnan, Eivind; Hess, Søren; Grupe, Peter;

    2015-01-01

    Structural imaging with computed tomography (CT) and MR imaging is the mainstay in primary diagnosis of primary brain tumors, but these modalities depend on morphologic appearance and an intact blood-brain barrier, and important aspects of tumor biology are not addressed. Such issues may be...... alleviated by (18)F-fluorodeoxyglucose (FDG)-PET and FDG-PET/CT imaging, which may provide clinically important information with regard to primary differentiation between tumor types, initial staging and risk stratification, therapy planning, response evaluation, and recurrence detection. This article...

  12. The effect of radiotherapy on rat pulmonary tumor model with PET/CT

    Objective: The aim of this study was to understand the role of PET/CT in monitoring the therapeutic effect of radiotherapy (RT) on lung cancer with Wistar rats. Methods: Thirty Wistar in-bred strain rats (6-8 weeks, weighed 180-280 g, female, ordinary) were made into Lewis pulmonary tumor model rats. 18F-fluorodeoxyglucose (FDG) PET/CT was performed when tumor reached 1.5-2.0 cm in greatest diameter (4-6 weeks) as a baseline. In order to get the optimal time point of PET/CT for monitoring RT effect in rat cancer model, PET/CT was performed at the 3rd day, 1st, 2n'd, 3rd, and 4th week after giving single dose of 5 Gy to each rat. Standardized uptake values (SUV) from FDG PET were measured and rats were sacrificed at different time point for validation. Besides, the expressions of glucose transport1 (Glut1) in tumor tissue were studied using immunohistochemistry. The level of tumor cell apoptosis, degradation, and necrosis were observed. SPSS 11.0 software was used for data analyses. Results: A negative correlation of SUV uptake and time after RT and negative correlation of Glut1 expression and time after RT were observed in rat tumors, respectively. Positive correlation of SUV uptake and Glut1 expression in rat tumors was observed (Spearman rank correlation test, rs = 0.97, P rd day and 0.18 ± 0.10 at the 4th week after RT (F=15.126, Prd day and 0. 1320 ± 0.04 at the 4th week after RT. The amounts of tumor cell apoptosis, degradation, and necrosis increased with time after RT. Conclusion: Though FDG PET could monitor the therapeutic effect at the 3rd day after giving single dose of RT to rat lung tumor model, the optimal time was the the 4th week after treatment. (authors)

  13. Evaluation of malignant solid tumor in childhood with FDG-PET

    Usefulness of FDG-PET (18F-deoxyglucose PET) was examined in evaluation of diagnosis and therapeutic efficacy of childhood malignant solid tumors. Subjects were 32 patients (16 males) of the median age of 7 y (1 - 27 y), involving those with neuroblastoma (9 cases), hepatoblastoma (4), chronic granulomatous disorder (4) and others (each ≤2). They underwent 75 FDG-PET examinations for diagnosis before and during treatment in authors' hospital in the period from May 2001 to December 2003. Standard uptake value (SUV), 1 x 1 cm region of interest (ROI) of abnormally high distribution area of radioactivity in the lesion/FDG dose/kg body wt., was used for evaluation: SUV>1.5 was defined positive. In neuroblastoma, FDG was found to be highly distributed and kinetics of SUV, to be useful for evaluation of therapeutic efficacy and early metastasis detection. In some cases of hepatoblastoma, the therapeutic effectiveness and recurrence were not satisfactorily evaluative. The distribution of FDG was not satisfactory in Wilms' tumor relative to other tumors. The PET was thought to be useful, despite their small case number examined, for those evaluations of Ewing's tumor, dysgerminoma and Langerhans cell histiocytosis. Thus FDG-PET was found useful for detection, evaluation of therapeutic efficacy and early metastasis detection of pediatric malignant solid tumors. (T.I.)

  14. Automatic Lung Tumor Segmentation on PET/CT Images Using Fuzzy Markov Random Field Model

    Yu Guo

    2014-01-01

    Full Text Available The combination of positron emission tomography (PET and CT images provides complementary functional and anatomical information of human tissues and it has been used for better tumor volume definition of lung cancer. This paper proposed a robust method for automatic lung tumor segmentation on PET/CT images. The new method is based on fuzzy Markov random field (MRF model. The combination of PET and CT image information is achieved by using a proper joint posterior probability distribution of observed features in the fuzzy MRF model which performs better than the commonly used Gaussian joint distribution. In this study, the PET and CT simulation images of 7 non-small cell lung cancer (NSCLC patients were used to evaluate the proposed method. Tumor segmentations with the proposed method and manual method by an experienced radiation oncologist on the fused images were performed, respectively. Segmentation results obtained with the two methods were similar and Dice’s similarity coefficient (DSC was 0.85 ± 0.013. It has been shown that effective and automatic segmentations can be achieved with this method for lung tumors which locate near other organs with similar intensities in PET and CT images, such as when the tumors extend into chest wall or mediastinum.

  15. 18F-FDG PET/CT is Useful for pretreatment Assessment of the Histopathologic Type of Thymic Epithelial Tumors

    This study was performed to assess the usefulness of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) of PET/computed tomography (CT) for distinguishing thymic epithelial tumors according to World Health Organization (WHO) classifications. We analyzed a total of 45 patients (range, 29-75 years of age; mean, 55 years) with pathologically confirmed thymic epithelial tumors who underwent pretreatment 18F-FDG PET or PET/CT between November 2003 and October 2009. The size, visual grading of uptake value, peak standardized uptake value (SUVpeak), uptake pattern, and contour of each tumor, and associated findings on PET or PET/CT, were analyzed relative to the three simplified WHO subgroups: lee-invasive thymomas (types A and AB), more-invasive thymomas (types B1, B2, and B3) and thymic carcinomas. We statistically assessed the relationship of 18F-FDG PET or PET/CT findings with these simplified subgroups. Of the 45 patients, ten had less-invasive thymomas, 23 had more-invasive thymomas, and 12 had thymic carcinomas. The SUVpeak of the less- and more-invasive thymomas were significantly lower than those of thymic carcinomas (p18F-FDG PET or PET/CT differed significantly by histologic subgroups. Pretreatment evaluation with 18F-FDG PET or PET/CT might be helpful in differentiating subgroups of thymic epithelial tumors.

  16. A new dimension of FDG-PET interpretation: assessment of tumor biology

    Kwee, Thomas C. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Basu, Sandip [Tata Memorial Center Annexe, Radiation Medicine Center (Bhabha Atomic Research Center), Bombay (India); Hospital of the University of Pennsylvania, Division of Nuclear Medicine, Philadelphia, PA (United States); Saboury, Babak; Torigian, Drew A.; Alavi, Abass [Hospital of the University of Pennsylvania, Division of Nuclear Medicine, Philadelphia, PA (United States); Ambrosini, Valentina [Sant' Orsola-Malpighi University Hospital, Department of Nuclear Medicine, Bologna (Italy)

    2011-06-15

    {sup 18}F-Fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) is increasingly being used for the evaluation of several malignancies. Key to the correct interpretation of oncological FDG-PET studies is awareness of the concept that the degree of FDG uptake reflects the biology of the tumor in many cancers. More specifically, cancers with high FDG uptake are often histologically and clinically more aggressive than those with low or no FDG uptake. Therefore, although a negative FDG-PET scan in a patient with a cancer that has a size above the spatial resolution of PET may be interpreted as false-negative in terms of tumor detectability, it should in fact be regarded as true-negative from the view-point of tumor biology. This nonsystematic review will give examples of several major cancers in which the relationship between FDG avidity and tumor biology is applicable, and emphasizes the need to reconsider the definition of a ''false-negative'' FDG-PET scan in clinical oncology. (orig.)

  17. A new dimension of FDG-PET interpretation: assessment of tumor biology

    18F-Fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) is increasingly being used for the evaluation of several malignancies. Key to the correct interpretation of oncological FDG-PET studies is awareness of the concept that the degree of FDG uptake reflects the biology of the tumor in many cancers. More specifically, cancers with high FDG uptake are often histologically and clinically more aggressive than those with low or no FDG uptake. Therefore, although a negative FDG-PET scan in a patient with a cancer that has a size above the spatial resolution of PET may be interpreted as false-negative in terms of tumor detectability, it should in fact be regarded as true-negative from the view-point of tumor biology. This nonsystematic review will give examples of several major cancers in which the relationship between FDG avidity and tumor biology is applicable, and emphasizes the need to reconsider the definition of a ''false-negative'' FDG-PET scan in clinical oncology. (orig.)

  18. Comparative evaluation of 11C methionine (MET-PET) and 18F flurodeoxyglucose (FDG) PET/CT for detection of recurrent brain tumors

    Full text: Comparative evaluation of 11C Methionine (MET-PET) and 18F flurodeoxyglucose (FDG) PET/CT for detection of recurrent brain tumors. Patients and Methods: 23 post-operative, histologically proven cases of primary brain tumors were included; there were two cases of grade I (WHO), 9 cases of grade II, 5 cases of grade III, 3 cases of grade IV, 3 medulloblastomas and one gliosarcoma. Ratio of M:F=16:7, age 27.5+14.4 years (range 5-56 years). All patients underwent the MET-PET and FDG-PET scans on the same day. Images were evaluated for recurrence using visual analysis and final results were compared with MRI/MRS and follow up as gold standard. Results: Fourteen cases were positive for recurrence on the MET-PET study while FDG was unequivocally positive in eleven cases. MET-PET scans were true negative for recurrence in nine cases and concurrent with the MRI/MRS findings in all 23 cases. Tumor to background ratio for the MET-PET study were 2.2+.55. Conclusion: MET-PET is superior to FDG-PET for detection of recurrence in both low and high grade gliomas and has excellent correlation with MRI/MRS

  19. Diagnosis of maxillofacial tumor with L-3-[18F]-fluoro-alpha-methyltyrosine (FMT) PET. A comparative study with FDG-PET

    The objective of this study was to compare L-3-[18F]-fluoro-α-methyltyrosine (FMT)-positron emission tomography (PET) and 2-[18F]-fluoro-2-deoxy-D-glucose (FDG)-PET in the differential diagnosis of maxillofacial tumors. This study included 36 patients (16 males, 20 females; 31-90 years old) with untreated malignant tumors (34 squamous cell carcinoma, one mucoepidermoid carcinoma, one rhabdomyosarcoma) and seven patients (five males, two females; 32-81 years old) with benign lesions. In all patients, both FMT-PET and FDG-PET were performed within two weeks before biopsy or treatment of the lesions. To evaluate the diagnostic usefulness of FMT-PET and FDG-PET, visual interpretation and semiquantitative analysis were performed. PET images were rated according to the contrast of tumor uptake as compared with background, and were statistically analyzed. As a semiquantitative analysis, standardized uptake values (SUV) of the primary tumors were measured, and the SUV data were analyzed using receiver operating characteristic (ROC) curves. The mean SUV of the malignant lesions were significantly higher than those of the benign lesions in both FMT-PET (2.62±1.58 vs. 1.20±0.30, p<0.01) and FDG-PET (9.17±5.06 vs. 3.14±1.34, p<0.01). A positive correlation (r=0.567, p<0.0001, n=46) was noted between FMT and FDG. ROC analysis revealed that there was no statistically significant difference in SUVs between FMT and FDG for differentiating malignant tumors. In 27 of 36 patients, FMT-PET had better contrast of malignant tumor visualization to the surrounding normal structures by visual assessment (p<0.005, binomial proportion test). Differential diagnosis of FMT-PET based on the uptake in maxillofacial tumors is equivalent to FDG-PET. However, the contrast of FMT uptake between maxillofacial tumors and the surrounding normal structures is higher than that of FDG, indicating the possibility of accurate diagnosis of maxillofacial tumors by FMT-PET. (author)

  20. The usefulness of 18F-FDG PET in patients with head and neck tumors

    Objective: The purpose of this study is to assess the usefulness of 18F-fluorodeoxyglucose (FDG) PET in patients with head and neck tumors. Methods: Thirty-nine patients (56 studies) with pathologically confirmed head and neck tumors underwent whole body 18F-FDG PET imaging for staging (5 cases) or for post-therapeutic monitoring and restaging. The results of whole body 18F-FDG PET imaging were evaluated with both visual and semiquantitative analyses (standardized uptake value, SUV). Results: (1) 18F-FDG PET helped to define the extent of lesions in 3 patients and downstage another patient before treatment, and accurately detected residual or recurrent lesions in 6, local lymph node metastasis in 11, lung and bone metastases in 4 and 3 cases after treatment. (2) Of 22 positive 18F-FDG PET imaging, 20 were true positive confirmed by surgeries or follow-up studies. All of 17 patients with negative 18F-FDG PET findings remained disease-free during follow-up. The sensitivity, specificity and accuracy of 18F-FDG PET imaging in detecting residual, recurrent and metastatic lesions were 100%, 89.5%, and 94.9% respectively. (3) 18F-FDG PET imaging detected more lesions than CT or MRI in 3 of 21 cases, and corrected another 6 CT or MRI false-positive findings. (4) Consecutive PET studies were carried out in 9 patients. Remission was found in 5 patients and progression in 3. In one patient with nasopharyngeal carcinoma, PET imaging showed complete response of primary lesion and metastatic lymph nodes to treatment, but found another high uptake focus in the middle part of descending colon which was confirmed to be an adenoma by colonoscopy. Conclusion: Due to its high sensitivity and accuracy in the detection of residual, recurrent, metastatic lesions and of second primary tumor, FDG PET imaging is a useful modality for staging and post-therapeutic follow-up in patients with head and neck tumors. (authors)

  1. The clinical value of PET/CT in therapeutic management of the malignant tumor

    Objective: To evaluate the clinical value of hybrid PET/CT in therapeutic management of the malignant tumor. Methods: 69 patients with malignant tumor without accepting any treatment, who were diagnosed by either pathology (24 patients) or clinical data (45 patients), were analyzed in this study. The age of the 20 females and 49 males ranged between 26 and 99 years (mean 63 years). PET/CT scans were performed using Discovery LS-PET/CT system (GE Discovery LS, CT attenuation correction, OSEM reconstruction), after injection of 5.55 MBq/kg FDG 40 minutes. Results: l. PET/CT showed 18 patients with single lesion and 51 patients with multiple lesions. while in CT imaging showed 47 patients with single lesion before PET/CT scanning. 29 (61.7%) patients were changed the clinical stage and therapeutic scheme after PET/CT performing. 2. Offered biological target orientation to radiotherapy or operation extension to surgery: radiotherapy doctors used PET/CT fusion imaging to direct radiotherapy orientation to 29 patients who were fit for radiotherapy. Five of them, who had treated by MM50 for one period of treatment, reexamined PET/CT after one month later, the former tumor was disappeared or shirked and the metabolism of glucose returned to normal. 10 patients were operated after the doctor confirmed the operation extension and operation path according to the PET/CT fusion images. The pathological results showed no carcinoma cell implicated or soakage in surgery cutting margins. The metastasis lymph nodes were completely removed. One patient, her operation was failed, was diagnosed primary lung cancer with hilus and lymph nodes metastases by PET/CT which indicated that the operation was not suitable for this patient. Conclusion: Hybrid PFT/CT imaging may offer an important tool in therapeutic management of the malignant tumor. One, it can provide more accurate diagnosis for clinical stage of the malignant tumor and assistant doctor's to draw the therapeutic scheme. Two, it

  2. Lung PET scan

    Chest PET scan; Lung positron emission tomography; PET - chest; PET - lung; PET - tumor imaging ... A PET scan requires a small amount of tracer. The tracer is given through a vein (IV), usually on ...

  3. [A Case of Metastatic Seminomatous Testicular Tumor with Complicated Diagnosis by FDG-PET].

    Hashizume, Akihito; Mizuno, Nobuhiko; Kawai, Masaki; Kishida, Takeshi

    2016-07-01

    18F-fluorodeoxy glucose positron emission tomography (FDG-PET) for evaluation of the post chemotherapy residual tumor of the seminomatous testicular germ cell tumor is recommended by several guidelines. We report a case whose residual tumor was evaluated by FDG PET but the results were difficult to interpret. A 41-year-old male with left seminomatous germ cell tumor of the testis and 60 mm retroperitoneal lymph node (RPLN) metastasis was referred to our hospital. The International Germ Cell Consensus Classification (IGCCC) was good prognosis. After high orchiectomy, three cycles of bleomycin, etoposide, and cisplatin (BEP) chemotherapy normalized the tumor marker and the RPLN decreased to 15 mm. The standardized uptake value (SUV) max at the RPLN by FDG-PET was 2.93. Although residual viable cells were suspected, the SUV max was relatively low. Thus surveillance without additional therapy was selected. After observation for 25 weeks, the tumor grew to 25 mm. Then four cycles of paclitaxel, ifosfamide, and cisplatin (TIP) chemotherapy were indicated for the recurrence. The RPLN was decreased to 15 mm, but the SUV max was still as high as 2.67 at 6 weeks after the last chemotherapy. We dissected the residual tumor suspecting viable cancer, but the pathological examination revealed necrotic tissue without any viable cells. He has had no signs of recurrence for 1 year and 9 months after the operation. PMID:27569358

  4. PET in tumor imaging: research only or a cost effective clinical tool?

    PET imaging has for many years been a versatile tool for non-invasive imaging of neuro-physiology and, indeed, whole body physiology. Quantitative PET imaging of trace amounts of radioactivity is scientifically elegant and can be very complex. This lecture focuses on whether and where this test is clinically useful. Because of the research tradition, PET imaging has been perceived as an 'expensive' test, as it costs more per scan than CT and MRI scans at most institutions. Such a superficial analysis is incorrect, however, as it is increasingly recognized that imaging costs, which in some circumstances will be increased by the use of PET, are only a relatively small component of patient care costs. Thus, PET may raise imaging costs and the number of imaging procedures in some settings, though PET may reduce imaging test numbers in other settings. However, the analysis must focus on the total costs of patient management. Analyses focused on total patient care costs, including cost of hospitalization and cost surgery as well as imaging costs, have shown that PET can substantially reduce total patient care costs in several settings. This is achieved by providing a more accurate diagnosis, and thus having fewer instances of an incorrect diagnosis resulting in subsequent inappropriate surgery or investigations. Several institutions have shown scenarios in which PET for tumor imaging is cost effective. While the specific results of the analyses vary based on disease prevalence and cost input values for each procedure, as well as the projected performance of PET, the similar results showing total care cost savings in the management of several common cancers, strongly supports the rational for the use of PET in cancer management. In addition, promising clinical results are forthcoming in several other illnesses, suggesting PET will have broader utility than these uses, alone. Thus, while PET is an 'expensive' imaging procedure and has considerable utility as a research

  5. Carbon-11-labeled daunorubicin and verapamil for probing P-glycoprotein in tumors with PET

    Elsinga, PH; Franssen, EJF; Hendrikse, NH; Fluks, L; Weemaes, AMA; vanderGraaf, WTA; deVries, GE; Visser, GM; Vaalburg, W

    1996-01-01

    One of the mechanisms for multidrug resistance (MDR) of tumors is an overexpression of the P-glycoprotein (P-gp). The cytostatic agent daunorubicin and the modulator verapamil were labeled with C-11 to probe P-gp with PET. Methods: Carbon-11-daunorubicin was prepared from (CCH2N2)-C-11 with an aldeh

  6. Quantitative Assessment of Heterogeneity in Tumor Metabolism Using FDG-PET

    Purpose: [18F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) images are usually quantitatively analyzed in “whole-tumor” volumes of interest. Also parameters determined with dynamic PET acquisitions, such as the Patlak glucose metabolic rate (MRglc) and pharmacokinetic rate constants of two-tissue compartment modeling, are most often derived per lesion. We propose segmentation of tumors to determine tumor heterogeneity, potentially useful for dose-painting in radiotherapy and elucidating mechanisms of FDG uptake. Methods and Materials: In 41 patients with 104 lesions, dynamic FDG-PET was performed. On MRglc images, tumors were segmented in quartiles of background subtracted maximum MRglc (0%–25%, 25%–50%, 50%–75%, and 75%–100%). Pharmacokinetic analysis was performed using an irreversible two-tissue compartment model in the three segments with highest MRglc to determine the rate constants of FDG metabolism. Results: From the highest to the lowest quartile, significant decreases of uptake (K1), washout (k2), and phosphorylation (k3) rate constants were seen with significant increases in tissue blood volume fraction (Vb). Conclusions: Tumor regions with highest MRglc are characterized by high cellular uptake and phosphorylation rate constants with relatively low blood volume fractions. In regions with less metabolic activity, the blood volume fraction increases and cellular uptake, washout, and phosphorylation rate constants decrease. These results support the hypothesis that regional tumor glucose phosphorylation rate is not dependent on the transport of nutrients (i.e., FDG) to the tumor.

  7. 18F-FDG PET-CT in diagnosis of tumor thrombus

    Full text: Venous thromboembolism is a relatively common phenomenon in cancer patients while tumor thrombosis is a rare complication of solid cancers. The correct diagnosis of tumor thrombosis and its differentiation from benign thrombus can change patient management and prevent unnecessary anticoagulation treatment. Materials and Methods: We conducted a retrospective review of FDG PET-CT scans of patients who underwent the study between July 2007 and July 2010. Any focal and/or linear area of increased FDG uptake (more than mediastinal blood pool) conforming to a blood vessel was taken as positive. SUVmax of the thrombus, SUVmax of tumor (if any) and SUVmax of mediastinal blood pool were calculated. PET-CT results were confirmed with clinical follow up, structural imaging and histopathology when available. Results: Total 24 patients (15 male and 9 female) with mean age of 43.8 years (range: 3-72; median-47.5) were evaluated. All patients underwent PET/CT for staging or restaging of a known malignancy and had a FDG avid thrombus. Based on structural imaging and clinical follow up, 9 patients had benign thromboembolism and 13 patients had tumor thrombosis. On FDG PET-CT, uptake in the thrombus was linear in 18 patients and focal in 6 patients. The most common site of thrombosis was IVC (n=14) followed by PV (n=7). One patient had catheter associated thrombosis. Four patients had only the thrombus as the FDG avid foci while remaining 18 patients had other FDG avid focus of disease. The mean SUVmax in the benign thrombosis group was 3.2 (range: 2.3-4.6; median-3.3). The mean SUVmax in the tumor thrombosis group was 6.0 (range: 2.3-13.8; median-3.3).There was significant difference in SUVmax between the two groups P = 0.013. On ROC analysis a cut off SUVmax of 3.63 was obtained to differentiate tumor thrombus from benign thromboembolism. In 6 patients FDG PET-CT detected occult vascular thrombosis, which was later confirmed with other imaging modality. Conclusion: FDG

  8. 18F-FDG PET/CT compared to conventional imaging modalities in pediatric primary bone tumors

    F-Fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) is useful in adults with primary bone tumors. Limited published data exist in children. To compare hybrid FDG positron emission tomography/computed tomography (PET/CT) with conventional imaging (CI) modalities in detecting malignant lesions, predicting response to chemotherapy and diagnosing physeal involvement in pediatric primary bone tumors. Retrospective analysis of PET/CT and CI reports with histopathology or follow-up > 6 months as reference standard. Response parameters and physeal involvement at diagnosis were compared to histopathology. A total of 314 lesions were detected in 86 scans. Excluding lung lesions, PET/CT had higher sensitivity and specificity than CI (83%, 98% and 78%, 97%, respectively). In lung lesions, PET/CT had higher specificity than CI (96% compared to 87%) but lower sensitivity (80% compared to 93%). Higher initial SUVmax and greater SUVmax reduction on PET/CT after chemotherapy predicted a good response. Change in tumor size on MRI did not predict response. Both PET/CT and MRI were very sensitive but of low specificity in predicting physeal tumor involvement. PET/CT appears more accurate than CI in detecting malignant lesions in childhood primary bone tumors, excluding lung lesions. It seems better than MRI at predicting tumor response to chemotherapy. (orig.)

  9. {sup 18}F-FDG PET/CT compared to conventional imaging modalities in pediatric primary bone tumors

    London, Kevin [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Discipline of Paediatrics and Child Health, Sydney Medical School, Sydney, NSW (Australia); Stege, Claudia; Kaspers, Gertjan [VU Medical Centre, Divisions of Paediatric Oncology/Haematology, Amsterdam (Netherlands); Cross, Siobhan; Dalla-Pozza, Luciano [The Children' s Hospital at Westmead, Department of Oncology, Sydney (Australia); Onikul, Ella [The Children' s Hospital at Westmead, Department of Medical Imaging, Sydney (Australia); Graf, Nicole [The Children' s Hospital at Westmead, Department of Pathology, Sydney (Australia); Howman-Giles, Robert [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Discipline of Imaging, Sydney Medical School, Sydney, NSW (Australia)

    2012-04-15

    F-Fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) is useful in adults with primary bone tumors. Limited published data exist in children. To compare hybrid FDG positron emission tomography/computed tomography (PET/CT) with conventional imaging (CI) modalities in detecting malignant lesions, predicting response to chemotherapy and diagnosing physeal involvement in pediatric primary bone tumors. Retrospective analysis of PET/CT and CI reports with histopathology or follow-up > 6 months as reference standard. Response parameters and physeal involvement at diagnosis were compared to histopathology. A total of 314 lesions were detected in 86 scans. Excluding lung lesions, PET/CT had higher sensitivity and specificity than CI (83%, 98% and 78%, 97%, respectively). In lung lesions, PET/CT had higher specificity than CI (96% compared to 87%) but lower sensitivity (80% compared to 93%). Higher initial SUV{sub max} and greater SUV{sub max} reduction on PET/CT after chemotherapy predicted a good response. Change in tumor size on MRI did not predict response. Both PET/CT and MRI were very sensitive but of low specificity in predicting physeal tumor involvement. PET/CT appears more accurate than CI in detecting malignant lesions in childhood primary bone tumors, excluding lung lesions. It seems better than MRI at predicting tumor response to chemotherapy. (orig.)

  10. CT-guided automated detection of lung tumors on PET images

    Cui, Yunfeng; Zhao, Binsheng; Akhurst, Timothy J.; Yan, Jiayong; Schwartz, Lawrence H.

    2008-03-01

    The calculation of standardized uptake values (SUVs) in tumors on serial [ 18F]2-fluoro-2-deoxy-D-glucose ( 18F-FDG) positron emission tomography (PET) images is often used for the assessment of therapy response. We present a computerized method that automatically detects lung tumors on 18F-FDG PET/Computed Tomography (CT) images using both anatomic and metabolic information. First, on CT images, relevant organs, including lung, bone, liver and spleen, are automatically identified and segmented based on their locations and intensity distributions. Hot spots (SUV >= 1.5) on 18F-FDG PET images are then labeled using the connected component analysis. The resultant "hot objects" (geometrically connected hot spots in three dimensions) that fall into, reside at the edges or are in the vicinity of the lungs are considered as tumor candidates. To determine true lesions, further analyses are conducted, including reduction of tumor candidates by the masking out of hot objects within CT-determined normal organs, and analysis of candidate tumors' locations, intensity distributions and shapes on both CT and PET. The method was applied to 18F-FDG-PET/CT scans from 9 patients, on which 31 target lesions had been identified by a nuclear medicine radiologist during a Phase II lung cancer clinical trial. Out of 31 target lesions, 30 (97%) were detected by the computer method. However, sensitivity and specificity were not estimated because not all lesions had been marked up in the clinical trial. The method effectively excluded the hot spots caused by mediastinum, liver, spleen, skeletal muscle and bone metastasis.

  11. Use of PET in neuroendocrine tumors. In vivo applications and in vitro studies

    Eriksson, B.; Oerlefors, H.; Oeberg, K. [Uppsala Univ. Hospital, Uppsala (Sweden). Dept. of Medical Sciences; Langstroem, B.; Bergstroem, M. [Uppsala Univ. Hospital, Uppsala (Sweden). Dept. of Radiology; Sundin, A. [Uppsala Univ. Hospital, Uppsala (Sweden). Dept. of Medical Sciences; Uppsala Univ. Hospital, Uppsala (Sweden). Dept. of Radiology

    2000-03-01

    Positron emission tomography (PET) performed with various radiolabelled compounds facilitates the study of tumor biochemistry. If the tumor uptake of an administered tracer is greater than that of surrounding normal tissue, it is also possible to localize the tumor. In initial studies, {sup 18}F-labeled deoxyglucose (FDG) was attempted to visualize the tumors, since this tracer had been successfully used in oncology, reflecting increased glucose metabolism in cancerous tissue. However, this tracer was no to any significant degree taken up by the neuroendocrine tumors. Instead the serotonin precursor 5-hydroxytryptophan (5-HTP) labeled with {sup 11}C was used and showed an increased uptake and irreversible trapping of this tracer in carcinoid tumors. The uptake was selective and the resolution so high that we could detect more liver and lymph node metastases with PET than with CT or octreotide scintigraphy. One problem was, however, the high renal excretion of the tracer producing streaky artifacts in the area of interest. Elevation of U-5-HIAA (Urinary 5-hydroxyindoleacetic acid) is considered to be uncommon in endocrine pancreatic tumors (EPTs). It is currently exploring a wide range of biochemical systems, including enzymes and receptors, both for neurotransmitters and for peptides and proteins in in vitro essays with the potential to use some of the developed tracers for in vivo visualization and tumor biological studies. In conclusion, PET is a valuable tool in the diagnosis of neuroendocrine tumors. It can detect small lesions in the thorax and abdomen not detected by other methods, which has been of great value preoperatively in several cases. It detects more lesions in the liver and lymph nodes than other methods and furthermore, it can be used to monitor treatment effects.

  12. The relationship between boron neutron capture therapy (BNCT) and positron emission tomography (PET) for malignant brain tumors

    Boron neutron capture therapy (BNCT) is a particle irradiation therapy that is theoretically available for selective radiation of tumor cells. Boronophenylalanine-positron emission tomography (18F-BPA-PET) was used in this study. Boron is used as a tracer compound for the neutron capture reaction and has been particularly useful for the recent noncraniotomy BNCT. In this report, we introduce this type of PET as a principal axis in BNCT and relationship with PET. We calculated the drug accumulation to the tumor before neutron irradiation to individualize the treatment. We decided the indication for BNCT on the basis of a PET study and are now expanding the indications to other systemic cancers, including head and neck, lung, and liver cancers. In addition, other irradiation modalities have developed a radiation plan on the basis of a PET study, and several studies attempted improving the results; however, the lesion is exposed to high radiation doses and appear as high accumulation on BPA-PET during BNCT. We determined the neutron exposure time from the dosage for normal tissue in the actual treatment, but the lesion/normal tissue ratio obtained from BPA-PET is for evaluating the tumor dose and following the treatment plan. We also found that a PET study was useful in the follow-up stage to aid in diagnosis of pathologic conditions such as increase in tumor volume, recurrence, or radiation necrosis and for patients who had already been treated for malignant brain tumor. (author)

  13. Role of 18F FDG PET scan to localize tumor in patients of oncogenic osteomalacia

    Full text: Oncogenic osteomalacia is a rare paraneoplastic syndrome of renal phosphate wasting which is usually caused by phosphaturic mesenchymal tumors. Conventional radiologic techniques usually fail to detect these small, slow growing neoplasms located at unusual sites. The objective of this study was to evaluate the role of 18F FDG PET imaging in patients of oncogenic osteomalacia. Materials and Methods: Fifteen patients (8 males and 7 females) (mean age: 38.5 ± 12.2 years) with clinical and biochemical evidence of oncogenic osteomalacia were subjected to 'total' whole body 18F FDG PET scan including both limbs and skull views. The images were reconstructed and the final output was displayed as per the standard institution protocol. Results: 18F FDG PET imaging localized suspicious hypermetabolic foci of SUVmax ranging from 1.4 to 3.8 (Mean ± S.D.: 2.39 ± 0.63) suggesting presence of occult tumor in 11 of 15 patients. The suspected foci were localized in lower limbs in ten patients and in the petrous temporal region of skull in 1 patient. FDG localized tumors were histopathologically correlated in 6 patients who underwent surgical biopsy/excision after correlative radiological investigations. Four of these patients were cured after surgical excision while partial surgical excision/biopsy was performed in two patients. Conclusions: 18F FDG PET imaging is a promising technique for detection of occult tumors in patients of oncogenic osteomalacia. It is mandatory to include limbs in the field as these tumors are common in limbs and may be easily missed. Preoperative localization increases odds for cure after surgical removal of tumor

  14. 18 FDG-PET/CT: 21st century approach to leukemic tumors in 124 cases.

    Cunningham, Isabel; Kohno, Brigett

    2016-06-01

    Extramedullary tumors remain an obstacle to curing more acute leukemia patients. Their incidence is unknown because the presence of occult tumors that contribute to relapse is not routinely sought as in other cancers. No standard approach exists for treating tumors at most sites, apparent clinical response is typically followed by further tumors, and achievement of lengthy remission is uncommon. Body scanning with (18) FDG PET/CT now provides a means to identify the extent of occult tumors that enables directed tumor eradication and a way to evaluate tumor response. To evaluate its potential benefits, analysis was undertaken of 124 published cases scanned after apparent tumors were diagnosed. Clinical and radiologic exams underestimated extent of disease in over half of 100 cases. Among 70 cases that reported scans after various treatments, 70% achieved negative scans. Half relapsed subsequently but disease-free survivals up to 6 years were documented. These reported cases add to our knowledge of extramedullary leukemia in showing that further tumors are more likely than marrow relapse, clinical and radiologic evaluation of response is inadequate, intensive chemotherapy alone generally does not prevent progression and is associated with significant mortality, and tumor-directed plus systemic therapies appears the most effective approach, particularly to AML tumors. This analysis suggests this technology could increase our ability to eradicate all foci of leukemia, and identify tumors responsible for refractory, residual, and relapsed disease. PMID:26718745

  15. 124I-Iodopyridopyrimidinone for PET of Abl Kinase–Expressing Tumors In Vivo

    Doubrovin, Mikhail; Kochetkova, Tatiana; Santos, Elmer; Veach, Darren R.; Smith-Jones, Peter; Pillarsetty, Nagavarakishore; Balatoni, Julius; Bornmann, William; Gelovani, Juri; Larson, Steven M.

    2015-01-01

    Because of the recent development of an iodopyridopyrimidinone Abl protein kinase inhibitor (PKI), 124I-SKI-212230 (124I-SKI230), we investigated the feasibility of a PET-based molecular imaging method for the direct visualization of Abl kinase expression and PKI treatment. Methods In vitro pharmacokinetic properties, including specific and nonspecific binding of 124I-SKI230 to its Abl kinase target and interaction with other PKIs, were assessed in cell-free medium and chronic myelogenous leukemia (CML) cells overexpressing BCR-Abl (K562), in comparison with BT-474 cells that are low in Abl expression. In a xenograft tumor model, we assessed the in vivo pharmacokinetics of 124I-SKI230 using PET and postmortem tissue sampling. We also tested a paradigm of 124I-SKI230 PET after treatment of the animal with a dose of Abl-specific PKI for the monitoring of the tumor response. Results In vitro studies confirmed that SKI230 binds to Abl kinase with nanomolar affinity, that selective uptake occurs in cell lines known to express Abl kinase, that RNAi knock-down supports specificity of cellular uptake due to Abl kinase, and that imatinib, an archetype Abl PKI, completely displaces SKI230. With SKI230, we obtained successful in vivo PET of Abl-expressing human tumors in a nude rat. We were also able to demonstrate evidence of substrate inhibition of in vivo radiotracer uptake in the xenograft tumor after treatment of the animal as a model of PKI treatment monitoring. Conclusion These results support the hypothesis that molecular imaging using PET will be useful for the study of in vivo pharmacodynamics of Abl PKI molecular therapy in humans. PMID:20048131

  16. Imaging of sigma receptors in tumors by PET with [C-11]SA4503

    Aim: Sigma receptors are implicated in some diseases in the central nervous system (CNS), such as schizophrenia, depression, dementia and ischemia, and are also expressed in a variety of human tumors, such as melanoma, carcinoma of the breast, lung and prostate, and the brain tumor. Therefore, several radioligands have been proposed for imaging of sigma receptors by positron emission tomography (PET) and by single photon emission computed tomography. Recently, we have applied [C-11]labeled 1-(3,4-dimethoxyphenethyl)-4-(3-phenylpropyl)piperazine ([C-11]SA4503) to mapping sigma1 receptors in the brain of monkeys and human. In the present study, we evaluated the potential of the [C-11]SA4503 PET for imaging of sigma receptors using the AH109A bearing rats, and the VX-2 carcinoma bearing rabbits. Materials and Methods: [C-11]SA4503 was injected i.v. into AH109A bearing rats, and the tissue distribution was measured by tissue dissection. To determine the receptor-specific uptake, cold SA4503 or haloperidol was co-injected into the other group of rats. The PET scanning were performed in the rats in the baseline condition and after pretreatment with haloperidol. In the VX-2 carcinoma bearing rabbits, PET scanning was also performed in the baseline and blockade conditions. The sigma receptors in the AH109A and VX-2 were measured in vitro by the standard membrane binding assays. Results: The sigma receptors were found in AH109A and VX-2. The density was much higher in VX-2 than in AH109A. In the tissue dissection study, the AH109A uptake of [C-11]SA4503 increased for 60 min after injection. By the co-injection of SA4503 or haloperidol, the AH109A uptake was enhanced. The PET study also confirmed that the radioactivity level in the AH109A was enhanced by the pretreatment with haloperidol. On the other hand, In the VX-2 carcinoma bearing rabbits, the radioactivity level of in VX-2 remained constant after initial uptake in the baseline PET measurement, but the VX-2 uptake was

  17. FDG-avid portal vein tumor thrombosis from hepatocellular carcinoma in contrast-enhanced FDG PET/CT

    Canh Nguyen; Huy Nguyen; Tan Ngo; Simone Maurea

    2015-01-01

    Objective(s): In this study, we aimed to describe the characteristics of portal vein tumor thrombosis (PVTT), complicating hepatocellular carcinoma (HCC) in contrast-enhanced FDG PET/CT scan. Methods: In this retrospective study, 9 HCC patients with FDG-avid PVTT were diagnosed by contrast-enhanced fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT), which is a combination of dynamic liver CT scan, multiphase imaging, and whole-body PET sca...

  18. Clinical relevance of F-18 FDG PET for imaging of neuroendocrine tumors

    Neuroendocrine tumors are characterized immunocytochemically by the expression of different peptides and biogenic amines. Hormones induce their biological action by binding to and stimulating specific membrane-associated receptors for e.g. somatostatin. The presence of somatostatin receptors (SR) has been described mainly in endocrine glands and the central nervous system. Interestingly, a large variety of human tumors, including gastroenteropancreatic (GEP) tumors and medullary thyroid carcinomas (MTC) also express a high density of SR and can be imaged with [111In-DTPA-D-Phe1]-pentetreotide. Cell proliferative activity is an important indicator of the growth of various malignant tumors associated with a poorer prognosis and Ki-67 expression. 18F-FDG is a marker of tumor viability, based upon the increased glycolysis that is associated with malignancy as compared with normal tissue. SR-containing neuroendocrine tumors are well-differentiated and tend to grow slowly. Furthermore, these tumors demonstrate inverse relationship between in vivo SR expression, cell proliferation (low Ki-67 expression) and FDG uptake (normal biodistribution). In comparison, less differentiated tumors, e.g. atypical carcinoids or MTC with increasing CEA levels show mitotic activity (high levels of Ki-67 immunoreactivity and increased FDG uptake) and often lack of SR. In conclusion, SR scintigraphy has been shown to localize well-differentiated neuroendocrine tumors. In contrast, PET imaging is valuable for predicting malignancy only in less differentiated tumors with increased glucose metabolism. Therefore, an additional F-18 FDG PET should be performed if SR scintigraphy (GEP tumors) or combined imaging using [111In-DTPA-D-Phe1]-pentetreotide and 99mTc(V)-DMSA (MTC) is negative. (orig.)

  19. Applications of PET imaging of neurological tumors with radiolabeled amino acids

    Routine diagnostics and treatment monitoring of brain tumors is usually based on contrast-enhanced magnetic resonance imaging (MRI). However, the capacity of structural MRI to differentiate neoplastic tissue from non-specific treatment changes may be limited especially after therapeutic interventions such as neurosurgical resection, radio- and chemotherapy. Metabolic imaging using PET may provide relevant additional information on tumor metabolism, which allows for more accurate diagnostics especially in clinically equivocal situations. In contrast to the widely used 18F-2-fluoro-2-deoxy-D-glucose, which exhibits a poor tumor-to-background contrast within the brain, amino acid tracers provide high sensitivity to detect primary tumors, recurrent or residual gliomas, including most low-grade gliomas. The method improves targeting of biopsy and provides additional information of tumor extent, which is helpful for planning neurosurgery and radiotherapy. In the further course of the disease, amino acid positron-emission tomography (PET) allows a sensitive monitoring of treatment response, the early detection of tumor recurrence, and an improved differentiation of tumor recurrence from treatment-related changes. In the past, the method had only limited availability due to the use of radiopharmaceuticals with a short half-life. In recent years, however, novel amino acid tracers labeled with positron emitters with a longer half-life have been developed and clinically validated which allow a more efficient and cost-effective application. These developments and the well-documented diagnostic performance of PET using radiolabeled amino acids suggest that its application continues to spread and that the method may be available as a routine diagnostic technique for certain indications in the near future.

  20. Dynamic {sup 11}C-methionine PET analysis has an additional value for differentiating malignant tumors from granulomas: an experimental study using small animal PET

    Zhao, Songji; Zhao, Yan [Hokkaido University, Department of Nuclear Medicine, Graduate School of Medicine, Sapporo (Japan); Hokkaido University, Department of Tracer Kinetics and Bioanalysis, Graduate School of Medicine, Sapporo (Japan); Kuge, Yuji; Hatano, Toshiyuki [Hokkaido University, Central Institute of Isotope Science, Sapporo (Japan); Yi, Min; Kohanawa, Masashi [Hokkaido University, Department of Advanced Medicine, Graduate School of Medicine, Sapporo (Japan); Magota, Keiichi; Tamaki, Nagara [Hokkaido University, Department of Nuclear Medicine, Graduate School of Medicine, Sapporo (Japan); Nishijima, Ken-ichi [Hokkaido University, Department of Molecular Imaging, Graduate School of Medicine, Sapporo (Japan)

    2011-10-15

    We evaluated whether the dynamic profile of L-{sup 11}C-methionine ({sup 11}C-MET) may have an additional value in differentiating malignant tumors from granulomas in experimental rat models by small animal positron emission tomography (PET). Rhodococcus aurantiacus and allogenic rat C6 glioma cells were inoculated, respectively, into the right and left calf muscles to generate a rat model bearing both granulomas and tumors (n = 6). Ten days after the inoculations, dynamic {sup 11}C-MET PET was performed by small animal PET up to 120 min after injection of {sup 11}C-MET. The next day, after overnight fasting, the rats were injected with {sup 18}F-2-deoxy-2-fluoro-D-glucose ({sup 18}F-FDG), and dynamic {sup 18}F-FDG PET was performed up to 180 min. The time-activity curves, static images, and mean standardized uptake value (SUV) in the lesions were calculated. {sup 11}C-MET uptake in the granuloma showed a slow exponential clearance after an initial distribution, while the uptake in the tumor gradually increased with time. The dynamic pattern of {sup 11}C-MET uptake in the granuloma was significantly different from that in the tumor (p < 0.001). In the static analysis of {sup 11}C-MET, visual assessment and SUV analysis could not differentiate the tumor from the granuloma in all cases, although the mean SUV in the granuloma (1.48 {+-} 0.09) was significantly lower than that in the tumor (1.72 {+-} 0.18, p < 0.01). The dynamic patterns, static images, and mean SUVs of {sup 18}F-FDG in the granuloma were similar to those in the tumor (p = NS). Dynamic {sup 11}C-MET PET has an additional value for differentiating malignant tumors from granulomatous lesions, which deserves further elucidation in clinical settings. (orig.)

  1. Dynamic 11C-methionine PET analysis has an additional value for differentiating malignant tumors from granulomas: an experimental study using small animal PET

    We evaluated whether the dynamic profile of L-11C-methionine (11C-MET) may have an additional value in differentiating malignant tumors from granulomas in experimental rat models by small animal positron emission tomography (PET). Rhodococcus aurantiacus and allogenic rat C6 glioma cells were inoculated, respectively, into the right and left calf muscles to generate a rat model bearing both granulomas and tumors (n = 6). Ten days after the inoculations, dynamic 11C-MET PET was performed by small animal PET up to 120 min after injection of 11C-MET. The next day, after overnight fasting, the rats were injected with 18F-2-deoxy-2-fluoro-D-glucose (18F-FDG), and dynamic 18F-FDG PET was performed up to 180 min. The time-activity curves, static images, and mean standardized uptake value (SUV) in the lesions were calculated. 11C-MET uptake in the granuloma showed a slow exponential clearance after an initial distribution, while the uptake in the tumor gradually increased with time. The dynamic pattern of 11C-MET uptake in the granuloma was significantly different from that in the tumor (p 11C-MET, visual assessment and SUV analysis could not differentiate the tumor from the granuloma in all cases, although the mean SUV in the granuloma (1.48 ± 0.09) was significantly lower than that in the tumor (1.72 ± 0.18, p 18F-FDG in the granuloma were similar to those in the tumor (p = NS). Dynamic 11C-MET PET has an additional value for differentiating malignant tumors from granulomatous lesions, which deserves further elucidation in clinical settings. (orig.)

  2. Evaluating image reconstruction methods for tumor detection performance in whole-body PET oncology imaging

    Lartizien, Carole; Kinahan, Paul E.; Comtat, Claude; Lin, Michael; Swensson, Richard G.; Trebossen, Regine; Bendriem, Bernard

    2000-04-01

    This work presents initial results from observer detection performance studies using the same volume visualization software tools that are used in clinical PET oncology imaging. Research into the FORE+OSEM and FORE+AWOSEM statistical image reconstruction methods tailored to whole- body 3D PET oncology imaging have indicated potential improvements in image SNR compared to currently used analytic reconstruction methods (FBP). To assess the resulting impact of these reconstruction methods on the performance of human observers in detecting and localizing tumors, we use a non- Monte Carlo technique to generate multiple statistically accurate realizations of 3D whole-body PET data, based on an extended MCAT phantom and with clinically realistic levels of statistical noise. For each realization, we add a fixed number of randomly located 1 cm diam. lesions whose contrast is varied among pre-calibrated values so that the range of true positive fractions is well sampled. The observer is told the number of tumors and, similar to the AFROC method, asked to localize all of them. The true positive fraction for the three algorithms (FBP, FORE+OSEM, FORE+AWOSEM) as a function of lesion contrast is calculated, although other protocols could be compared. A confidence level for each tumor is also recorded for incorporation into later AFROC analysis.

  3. Role of PET/CT functional imaging on constructing a tumor radiotherapeutic biological target volume

    In studies on intensity modulated radiotherapy with conventional fractionation, different radiosensitivity areas require different irradiation doses. In tumor radiotherapy areas CR, boosts in radiotherapy doses should be determined according to whether there are survived tumor cells or not. To those survived cells, CT imaging has become the key tool to delineate the radiotherapy target. Thus, the study on the construction of biological target volume with PET/CT functional imaging, which could reflect either radiosensitivity or cell proliferation-related cell metabolism, anoxia and DNA number of various cell cycle phases, is an important research area. (authors)

  4. Improvement of internal tumor volumes of non-small cell lung cancer patients for radiation treatment planning using interpolated average CT in PET/CT.

    Yao-Ching Wang

    Full Text Available Respiratory motion causes uncertainties in tumor edges on either computed tomography (CT or positron emission tomography (PET images and causes misalignment when registering PET and CT images. This phenomenon may cause radiation oncologists to delineate tumor volume inaccurately in radiotherapy treatment planning. The purpose of this study was to analyze radiology applications using interpolated average CT (IACT as attenuation correction (AC to diminish the occurrence of this scenario. Thirteen non-small cell lung cancer patients were recruited for the present comparison study. Each patient had full-inspiration, full-expiration CT images and free breathing PET images by an integrated PET/CT scan. IACT for AC in PET(IACT was used to reduce the PET/CT misalignment. The standardized uptake value (SUV correction with a low radiation dose was applied, and its tumor volume delineation was compared to those from HCT/PET(HCT. The misalignment between the PET(IACT and IACT was reduced when compared to the difference between PET(HCT and HCT. The range of tumor motion was from 4 to 17 mm in the patient cohort. For HCT and PET(HCT, correction was from 72% to 91%, while for IACT and PET(IACT, correction was from 73% to 93% (*p<0.0001. The maximum and minimum differences in SUVmax were 0.18% and 27.27% for PET(HCT and PET(IACT, respectively. The largest percentage differences in the tumor volumes between HCT/PET and IACT/PET were observed in tumors located in the lowest lobe of the lung. Internal tumor volume defined by functional information using IACT/PET(IACT fusion images for lung cancer would reduce the inaccuracy of tumor delineation in radiation therapy planning.

  5. 18F-EF5 PET Is Predictive of Response to Fractionated Radiotherapy in Preclinical Tumor Models.

    Ali, Rehan; Apte, Sandeep; Vilalta, Marta; Subbarayan, Murugesan; Miao, Zheng; Chin, Frederick T; Graves, Edward E

    2015-01-01

    We evaluated the relationship between pre-treatment positron emission tomography (PET) using the hypoxic tracer 18F-[2-(2-nitro-1-H-imidazol-1-yl)-N-(2,2,3,3,3- pentafluoropropyl) acetamide] (18F-EF5) and the response of preclinical tumor models to a range of fractionated radiotherapies. Subcutaneous HT29, A549 and RKO tumors grown in nude mice were imaged using 18F-EF5 positron emission tomography (PET) in order to characterize the extent and heterogeneity of hypoxia in these systems. Based on these results, 80 A549 tumors were subsequently grown and imaged using 18F-EF5 PET, and then treated with one, two, or four fraction radiation treatments to a total dose of 10-40 Gy. Response was monitored by serial caliper measurements of tumor volume. Longitudinal post-treatment 18F-EF5 PET imaging was performed on a subset of tumors. Terminal histologic analysis was performed to validate 18F-EF5 PET measures of hypoxia. EF5-positive tumors responded more poorly to low dose single fraction irradiation relative to EF5-negative tumors, however both groups responded similarly to larger single fraction doses. Irradiated tumors exhibited reduced 18F-EF5 uptake one month after treatment compared to control tumors. These findings indicate that pre- treatment 18F-EF5 PET can predict the response of tumors to single fraction radiation treatment. However, increasing the number of fractions delivered abrogates the difference in response between tumors with high and low EF5 uptake pre-treatment, in agreement with traditional radiobiology. PMID:26431331

  6. 18F-EF5 PET Is Predictive of Response to Fractionated Radiotherapy in Preclinical Tumor Models.

    Rehan Ali

    Full Text Available We evaluated the relationship between pre-treatment positron emission tomography (PET using the hypoxic tracer 18F-[2-(2-nitro-1-H-imidazol-1-yl-N-(2,2,3,3,3- pentafluoropropyl acetamide] (18F-EF5 and the response of preclinical tumor models to a range of fractionated radiotherapies. Subcutaneous HT29, A549 and RKO tumors grown in nude mice were imaged using 18F-EF5 positron emission tomography (PET in order to characterize the extent and heterogeneity of hypoxia in these systems. Based on these results, 80 A549 tumors were subsequently grown and imaged using 18F-EF5 PET, and then treated with one, two, or four fraction radiation treatments to a total dose of 10-40 Gy. Response was monitored by serial caliper measurements of tumor volume. Longitudinal post-treatment 18F-EF5 PET imaging was performed on a subset of tumors. Terminal histologic analysis was performed to validate 18F-EF5 PET measures of hypoxia. EF5-positive tumors responded more poorly to low dose single fraction irradiation relative to EF5-negative tumors, however both groups responded similarly to larger single fraction doses. Irradiated tumors exhibited reduced 18F-EF5 uptake one month after treatment compared to control tumors. These findings indicate that pre- treatment 18F-EF5 PET can predict the response of tumors to single fraction radiation treatment. However, increasing the number of fractions delivered abrogates the difference in response between tumors with high and low EF5 uptake pre-treatment, in agreement with traditional radiobiology.

  7. PET

    Mariager, Rasmus Mølgaard; Schmidt, Regin; Heiberg, Morten Rievers

    PET handler om den hemmelige tjenestes arbejde under den kolde krig 1945-1989. Her fortæller Regin Schmidt, Rasmus Mariager og Morten Heiberg om de mest dramatiske og interessante sager fra PET's arkiv. PET er på flere måder en udemokratisk institution, der er sat til at vogte over demokratiet....... Dens virksomhed er skjult for offentligheden, den overvåger borgernes aktiviteter, og den registrerer følsomme personoplysninger. Historien om PET rejser spørgsmålet om, hvad man skal gøre, når befolkningen i et demokrati er kritisk indstillet over for overvågningen af lovlige politiske aktiviteter......, mens myndighederne mener, at det er nødvendigt for at beskytte demokratiet. PET er på en gang en fortælling om konkrete aktioner og begivenheder i PET's arbejde og et stykke Danmarkshistorie. Det handler om overvågning, spioner, politisk ekstremisme og international terrorisme.  ...

  8. Thoracic tumor volume delineation in 4D-PET/CT by low dose interpolated CT for attenuation correction.

    Tzung-Chi Huang

    Full Text Available PURPOSE: 4D-PET/CT imaging is an excellent solution for reducing the breathing-induced effects in both CT and PET images. In 4D-PET/CT, 4D-CT images are selected to match those of 4D-PET phase by phase and the corresponding phases are used for attenuation correction in 4D-PET. However, the high radiation dose that patients acquire while undergoing 4D-CT imaging for diagnostic purposes remains a concern. This study aims to assess low-dose interpolated CT (ICT for PET attenuation correction (PETICT in thoracic tumor volume delineation. METHODS AND MATERIALS: Twelve thoracic cancer patients (10 esophageal and 2 lung cancer cases were recruited. All patients underwent 4D-PET/CT scans. The optical flow method based on image intensity gradient was applied to calculate the motion displacement in three dimensions for each voxel on two original extreme CT phases in the respiratory cycle, end-inspiration and end-expiration. The interpolated CTs were generated from two phases of the original 4D-CT using motion displacement. RESULTS: Tumor motion due to respiration was estimated in the anterior-posterior dimension, the lateral dimension and the superior-inferior dimension by the optical flow method. The PETICT and ICT (4D-PET ICT/ICT matched each other spatially in all the phases. The distortion of tumor shape and size resulting from respiratory motion artifacts were not observed in 4D-PETICT. The tumor volume measured by 4D-PET ICT/ICT correlated to the tumor volume measured by 4D-PET/CT (p = 0.98. CONCLUSIONS: 4D-PETICT consistently represented the interpretation of FDG uptake as effectively as 4D-PET. 4D-PET ICT/ICT is a low-dose alternative to 4D-CT and significantly improves the interpretation of PET and CT images, while solving the respiratory motion problem as effectively as 4D-PET/CT.

  9. PET tracers for somatostatin receptor imaging of neuroendocrine tumors

    Johnbeck, Camilla Bardram; Knigge, Ulrich; Kjær, Andreas

    2014-01-01

    the perfect neuroendocrine tumor imaging tracer. (68)Ga-labeled tracers coupled to synthetic somatostatin analogs with differences in affinity for the five somatostatin receptor subtypes are now widely applied in Europe. Comparison of sensitivity between the most used tracers - (68)Ga-DOTA-Tyr3......-octreotide, (68)Ga-DOTA-Tyr3-octreotate and (68)Ga-DOTA-l-Nal3-octreotide - shows little difference and expertise on the specific tracer used, and knowledge regarding physiological uptake might be more important than in vitro-proven differences in affinity. Using isotopes such as (18)F or (64)Cu might...

  10. Extensive tumor thrombus in a case of carcinoma lung detected by F18-FDG-PET/CT.

    Mudalsha, Ravina; Jacob, Mj; Pandit, Ag; Jora, Charu

    2011-04-01

    Tumor thrombus is a rare complication of solid cancers, mainly seen in cases of renal cell carcinoma, wilm's tumor, testicular carcinoma, adrenal cortical carcinoma and hepatocellular carcinoma.[1] Tumor thrombus in inferior vena cava is a rare complication of primary carcinoma lung. It should be identified so as to rule out venous thromboembolism and avoiding unnecessary anticoagulant therapy. We describe a case where F18-Fluorodeoxyglucose (FDG) positron emission tomography - computed tomography (PET/CT) helped to identify extensive tumor thrombus. PMID:22174524

  11. Extensive tumor thrombus in a case of carcinoma lung detected by 18F-FDG-PET/CT

    Tumor thrombus is a rare complication of solid cancers, mainly seen in cases of renal cell carcinoma, Wilm's tumor, testicular carcinoma, adrenal cortical carcinoma and hepatocellular carcinoma. Tumor thrombus in inferior vena cava is a rare complication of primary carcinoma lung. It should be identified so as to rule out venous thromboembolism and avoiding unnecessary anticoagulant therapy. We describe a case where 18F-Fluorodeoxyglucose (FDG) positron emission tomography - computed tomography (PET/CT) helped to identify extensive tumor thrombus. (author)

  12. SU-E-QI-20: A Review of Advanced PET and CT Image Features for the Evaluation of Tumor Response

    Lu, W [University of Maryland School of Medicine, Baltimore, MD (United States)

    2014-06-15

    Purpose: To review the literature in using quantitative PET and CT image features for the evaluation of tumor response. Methods: We reviewed and summarized more than fifty papers that use advanced, quantitative PET/CT image features for the evaluation of tumor response. We also discussed future works on extracting disease-specific features, combining multiple and complementary features in response modeling, delineating tumor in multimodality images, and exploring biological explanations of these advanced features. Results: Advanced PET image features considering spatial information, such as tumor volume, tumor shape, total glycolytic volume, histogram distance, and texture features (characterizing spatial distribution of FDG uptake) have been found more informative than the traditional SUVmax for the prediction of tumor response. Advanced CT features, including volumetric, attenuation, morphologic, structure, and texture descriptors, have also been found advantage over the traditional RECIST and WHO criteria in certain tumor types. Conclusions: Advanced, quantitative FDG PET/CT image features have been shown promising for the evaluation of tumor response. With the emerging multi-modality imaging performed at multiple time points for each patient, it becomes more important to analyze the serial images quantitatively, select and combine both complementary and contradictory information from various sources, for accurate and personalized evaluation of tumor response to therapy.

  13. FDG-PET during Therapy of Head and Neck Carcinomas. Prediction of tumor response and associations to tumor cell properties

    Introduction: Correlations between FDG uptake to single tumor properties, such as tumor grade, tumor cell proliferation or DNA ploidy have failed. Association between FDG metabolism during cytotoxic therapy, treatment outcome and tumor cell properties were evaluated in a prospective study of 47 patients with locally advanced head neck carcinomas (HNSCC) receiving radical treatment, radiotherapy with or without neoadjuvant cisplatinum-based chemotherapy. Methods: Repeated FDG PET scans with evaluation of metabolic rate of FDG (MR FDG) before and early during, either radiotherapy or initial chemotherapy. Fine needle aspiration of palpable node metastasis was performed in 31 patients immediately after each PET scan for analysis of S-phase (SPF), and DNA ploidy (analyzed by FCM and Image Cytometry; ICM). The associations between MR FDG and therapy outcome, and MR FDG and ploidy and s-phase were evaluated. We also studied changes in these properties during therapy. Results: Early changes in MR FDG were associated to treatment outcome, both survival and locoregional control. MR FDG below the median value during therapy was associated to a significantly better outcome, compared to MR FDG above the median value. This regards both 5 year-survival (72 % and 35% resp., p 0.0042) and locoregional control (96% and 55% resp., p 0.002). Analysis of DNA ploidy revealed differences depending on analyses used. ICM identified primarily more non-diploid tumors than FCM did, as well as more persisting non-diploid clones during treatment. No significant association to treatment outcome depending on DNA ploidy or SPF was seen.There was neither any significant association between DNA ploidy nor SPF to MR FDG. Conclusions: MR FDG during therapy was associated to therapy outcome, and thus enabling in vivo monitoring of metabolic response. Ploidy and SPF was not associated to FDG-metabolism

  14. FDG-PET provides the best correlation with the tumor specimen compared to MRI and CT in rectal cancer

    Purpose: To compare CT-, MR- and PET-CT based tumor length measurements in rectal cancer with pathology. Patients and Methods: Twenty-six rectal cancer patients underwent both MR and PET-CT imaging followed by short-course radiotherapy (RT 5 x 5 Gy) and surgery within 3 days after RT. Tumor length was measured manually and independently by 2 observers on CT, MR and PET. PET-based tumor length measurements were also generated automatically using the signal-to-background-ratio (SBR) method. All measurements were correlated with the tumor length on the pathological specimen. Results: CT-based measurements did not show a valuable correlation with pathology. MR-based measurements correlated only weakly, but still significantly (Pearson correlation = 0.55 resp. 0.57; p < 0.001). Manual PET measurements reached a good correlation with pathology, but less strong (Pearson correlation 0.72 and 0.76 for the two different observers) than automatic PET-CT based measurements, which provided the best correlation with pathology (Pearson correlation of 0.91 (p < 0.001)). Bland-Altman analysis demonstrated in general an overestimation of the tumor diameter using manual measurements, while the agreement of automatic contours and pathology was within acceptable ranges. A direct comparison of the different modalities revealed a significant better precision for PET-based auto-contours as compared to all other measurements. Conclusion: Automatically generated PET-CT based contours show the best correlation with the surgical specimen and thus provide a useful and powerful tool to accurately determine the largest tumor dimension in rectal cancer. This could be used as a quick and reliable tool for target delineation in radiotherapy. However, a 3D volume analysis is needed to confirm these results.

  15. Comparison of 18F-FET and 18F-FDG PET in brain tumors

    The purpose of this study was to compare the diagnostic value of positron emission tomography (PET) using [18F]-fluorodeoxyglucose (18F-FDG) and O-(2-[18F]fluoroethyl)-L-tyrosine (18F-FET) in patients with brain lesions suspicious of cerebral gliomas. Methods: Fifty-two patients with suspicion of cerebral glioma were included in this study. From 30 to 50 min after injection of 180 MBq 18F-FET, a first PET scan (18F-FET scan) was performed. Thereafter, 240 MBq 18F-FDG was injected and a second PET scan was acquired from 30 to 60 min after the second injection (18F-FET/18F-FDG scan). The cerebral accumulation of 18F-FDG was calculated by decay corrected subtraction of the 18F-FET scan from the 18F-FET/18F-FDG scan. Tracer uptake was evaluated by visual scoring and by lesion-to-background (L/B) ratios. The imaging results were compared with the histological results and prognosis. Results: Histology revealed 24 low-grade gliomas (LGG) of World Health Organization (WHO) Grade II and 19 high-grade gliomas (HGG) of WHO Grade III or IV, as well as nine others, mainly benign histologies. The gliomas showed increased 18F-FET uptake (>normal brain) in 86% and increased 18F-FDG uptake (>white matter) in 35%. 18F-FET PET provided diagnostically useful delineation of tumor extent while this was impractical with 18F-FDG due to high tracer uptake in the gray matter. A local maximum in the tumor area for biopsy guidance could be identified with 18F-FET in 76% and with 18F-FDG in 28%. The L/B ratios showed significant differences between LGG and HGG for both tracers but considerable overlap so that reliable preoperative grading was not possible. A significant correlation of tracer uptake with overall survival was found with 18F-FDG only. In some benign lesions like abscesses, increased uptake was observed for both tracers indicating a limited specificity of both techniques. Conclusions: 18F-FET PET is superior to 18F-FDG for biopsy guidance and treatment planning of cerebral gliomas

  16. Clinical evidence on PET-CT for radiation therapy planning in gastro-intestinal tumors

    A large number of histological and anatomically distinct malignancies originate from the gastro-intestinal (GI) tract. Radiotherapy (RT) plays an increasing role in the multimodal treatment of most of these malignancies. The proximity of different organs at risk such as the kidneys, the spinal cord and the small bowel and the potential toxicity associated with combined treatment modalities make accurate target volume delineation imperative. The ability of positron emission tomography (PET) imaging to visualize a so-called 'biological target volume' (BTV) may be helpful in this respect. Currently the most widely used tracer for diagnosis, staging, restaging and response assessment is [18F]Fluoro-deoxyglucose (FDG). Promising preliminary results in esophageal, pancreatic and anorectal cancers and colorectal liver metastasis suggest that FDG-PET might provide us with additional information useful in target volume delineation. Poor image resolution and a low sensitivity for lymph node detection currently obstructs its widespread implementation. Moreover, validation in large prospective trials and the pathological validation of the correct tumor volume is still lacking. In hepatocellular carcinoma (HCC) and gastric adenocarcinoma there is currently little evidence for the use of FDG-PET in target delineation. However more extensive research is warranted before the true value of FDG-PET in these sites can be assessed. Also other tracers are constantly being developed and investigated. Up to now however none of these tracers has found its way into the daily practice of target volume delineation.

  17. Delineation of FDG-PET tumors from heterogeneous background using spectral clustering

    This paper explored the feasibility of using spectral clustering to segment FDG-PET tumor in the presence of heterogeneous background. Spectral clustering refers to a class of clustering methods which employ the eigenstructure of a similarity matrix to partition image voxels into disjoint clusters. The similarity between two voxels was measured with the intensity distance scaled by voxel-varying factors capturing local statistics and the number of clusters was inferred based on rotating the eigenvector matrix for the maximally sparse representation. Metrics used to evaluate the segmentation accuracy included: Dice coefficient, Jaccard coefficient, false positive dice, false negative dice, symmetric mean absolute surface distance, and absolute volumetric difference. Comparison of segmentation results between the presented method and the adaptive thresholding method on the simulated PET data shows the former attains an overall better detection accuracy. Applying the presented method on patient data gave segmentation results in fairly good agreement with physician manual annotations. These results indicate that the presented method have the potential to accurately delineate complex shaped FDG-PET tumors containing inhomogeneous activities in the presence of heterogeneous background.

  18. WE-G-BRF-06: Positron Emission Tomography (PET)-Guided Dynamic Lung Tumor Tracking for Cancer Radiotherapy: First Patient Simulations

    Purpose: PET-guided dynamic tumor tracking is a novel concept of biologically targeted image guidance for radiotherapy. A dynamic tumor tracking algorithm based on list-mode PET data has been developed and previously tested on dynamic phantom data. In this study, we investigate if dynamic tumor tracking is clinically feasible by applying the method to lung cancer patient PET data. Methods: PET-guided tumor tracking estimates the target position of a segmented volume in PET images reconstructed continuously from accumulated coincidence events correlated with external respiratory motion, simulating real-time applications, i.e., only data up to the current time point is used to estimate the target position. A target volume is segmented with a 50% threshold, consistently, of the maximum intensity in the predetermined volume of interest. Through this algorithm, the PET-estimated trajectories are quantified from four lung cancer patients who have distinct tumor location and size. The accuracy of the PET-estimated trajectories is evaluated by comparing to external respiratory motion because the ground-truth of tumor motion is not known in patients; however, previous phantom studies demonstrated sub-2mm accuracy using clinically derived 3D tumor motion. Results: The overall similarity of motion patterns between the PET-estimated trajectories and the external respiratory traces implies that the PET-guided tracking algorithm can provide an acceptable level of targeting accuracy. However, there are variations in the tracking accuracy between tumors due to the quality of the segmentation which depends on target-to-background ratio, tumor location and size. Conclusion: For the first time, a dynamic tumor tracking algorithm has been applied to lung cancer patient PET data, demonstrating clinical feasibility of real-time tumor tracking for integrated PET-linacs. The target-to-background ratio is a significant factor determining accuracy: screening during treatment planning would

  19. Strategies of assessing and quantifying radiation treatment metabolic tumor response using F18 FDG Positron Emission Tomography (PET)

    The use of positron emission tomography (PET) using F-18 labeled fluorodeoxyglucose (FDG) for both oncology disease staging and radiation therapy target volume delineation has steadily increased over the last decade, and FDG-PET is today readily available in all major medical centers. The goal of anti tumor treatment, including chemotherapy and/or radiation therapy is to diminish a tumor cell population, ideally to the state of total eradication. Reducing the number of viable tumor cells can lead to a reduction in anatomical tumor size, and may also be correlated with decreased FDG uptake. Efforts to assess tumor response to therapy have attempted to describe and quantify changes in glucose utilization, also referred to as metabolic tumor response. In this review, an attempt is made to present and discuss methodologies to assess and quantify tumor metabolic response to radiation therapy or chemoradiation treatment courses.

  20. Diffusion-weighted and PET/MR Imaging after Radiation Therapy for Malignant Head and Neck Tumors.

    Varoquaux, Arthur; Rager, Olivier; Dulguerov, Pavel; Burkhardt, Karim; Ailianou, Angeliki; Becker, Minerva

    2015-01-01

    Interpreting imaging studies of the irradiated neck constitutes a challenge because of radiation therapy-induced tissue alterations, the variable appearances of recurrent tumors, and functional and metabolic phenomena that mimic disease. Therefore, morphologic magnetic resonance (MR) imaging, diffusion-weighted (DW) imaging, positron emission tomography with computed tomography (PET/CT), and software fusion of PET and MR imaging data sets are increasingly used to facilitate diagnosis in clinical practice. Because MR imaging and PET often yield complementary information, PET/MR imaging holds promise to facilitate differentiation of tumor recurrence from radiation therapy-induced changes and complications. This review focuses on clinical applications of DW and PET/MR imaging in the irradiated neck and discusses the added value of multiparametric imaging to solve diagnostic dilemmas. Radiologists should understand key features of radiation therapy-induced tissue alterations and potential complications seen at DW and PET/MR imaging, including edema, fibrosis, scar tissue, soft-tissue necrosis, bone and cartilage necrosis, cranial nerve palsy, and radiation therapy-induced arteriosclerosis, brain necrosis, and thyroid disorders. DW and PET/MR imaging also play a complementary role in detection of residual and recurrent disease. Interpretation pitfalls due to technical, functional, and metabolic phenomena should be recognized and avoided. Familiarity with DW and PET/MR imaging features of expected findings, potential complications, and treatment failure after radiation therapy increases diagnostic confidence when interpreting images of the irradiated neck. Online supplemental material is available for this article. PMID:26252192

  1. Non-Invasive imaging of small-animal tumors: high-frequency ultrasound vs. MicroPET.

    Liao, Ai-Ho; Li, Chen-Han; Cheng, Weng-Fang; Li, Pai-Chi

    2005-01-01

    Tumor volume measurement on small animals is important but currently invasive. We employ ultrasonic micro-imaging (UMI) in this study and demonstrate its feasibility. In addition, we use small animal positron emission tomography (microPET) as a preliminary effort to develop multi-modality small animal imaging techniques. The tumor growth curve from UMI is also compared to radioactivity from microPET. Both UMI and [18F] FDG microPET imaging were performed on C57BL/6J black mice bearing WF-3 ovary cancer cells at various stages from the second week till up to the eighth week. Segmentation and 3D reconstruction were also done. The growth curve was obtained in vivo noninvasively by UMI. The cell doubling time was 7.46 days according to UMI. This result was compared with vernier caliper measurement and radioactivity counting by microPET. In microPET, we obtained the time-activity curves from the tumor and the tumor-surrounding tissue. The tumor-to-normal-tissues ratios reached maximum at the fifth week after tumor cell implantation. PMID:17281549

  2. Comparison of tumor volumes derived from glucose metabolic rate maps and SUV maps in dynamic 18F-FDG PET.

    Visser, E.P.; Philippens, M.E.P.; Kienhorst, L.; Kaanders, J.H.A.M.; Corstens, F.H.M.; Geus-Oei, L.F. de; Oyen, W.J.G.

    2008-01-01

    Tumor delineation using noninvasive medical imaging modalities is important to determine the target volume in radiation treatment planning and to evaluate treatment response. It is expected that combined use of CT and functional information from 18F-FDG PET will improve tumor delineation. However, u

  3. Unusual Finding of a Tumor Thrombus Arising From Osteosarcoma Detected on 18F-NaF PET/CT.

    Verma, Priyanka; Purandare, Nilendu; Agrawal, Archi; Shah, Sneha; Rangarajan, Venkatesh

    2016-06-01

    Osteosarcoma is the most common bone sarcoma in adolescents and children. Tumor thrombus arising from osteosarcoma is rare. We describe the case of a 13-year-old girl with osteosarcoma of the right femur, in whom the F-NaF PET/CT was done for initial staging to look for skeletal metastases. The scan showed abnormal increased tracer uptake in the primary tumor and the right common femoral and external iliac vein representing a tumor thrombus. Our case emphasizes the importance of extraosseous findings on F-NaF PET/CT, which may result in important management changes. PMID:26909709

  4. Positive correlations between tumor uptake on FDG PET and energy expenditure of patients with esophageal cancer

    Cancer patients are prone to clinical malnutrition; moreover, the energy expenditure in patients with certain cancers is higher than that in healthy individuals, rendering their nutritional management a challenging issue. We hypothesized that 2-deoxy-2-[18F]fluoro-D-glucose (FDG) uptake on positron emission tomography (PET) may be related to the energy expenditure and analyzed the FDG uptake and energy expenditure in esophageal cancer patients to clarify this. Esophageal cancer patients [n=13, 10 males and 3 females, age 66.5±8.9 (51-82) years] were evaluated for FDG uptake using PET. The resting energy expenditure (REE) and basal energy expenditure (BEE) were calculated using indirect calorimetry and the Harris-Benedict formula, respectively. Regression analyses were performed to compare the parameters of imaging and energy expenditure. Positive correlations were found between tumor uptake on FDG PET and the parameters of energy expenditure. Among them, the correlations between SUVmax and the ratio of REE to BEE (REE/BEE, r=0.59; p=0.035) and between SUVmax and the difference between REE and BEE (REE-BEE, r=0.58; p=0.036) were moderate and statistically significant. Further, the correlation between tumor uptake expressed as a percentage (%TU) and REE/BEE was mild (r=0.51) but not significant (p=0.07), while that between %TU and REE-BEE was weak (r=0.42) and not significant (p=0.15). Significant positive correlations between SUVmax on FDG PET and energy expenditure were noted in our study; we consider that these results may aid in determining the nutritional management for esophageal cancer patients. (author)

  5. Single-scan dual-tracer FLT+FDG PET tumor characterization

    Kadrmas, Dan J.; Rust, Thomas C.; Hoffman, John M.

    2013-02-01

    Rapid multi-tracer PET aims to image two or more tracers in a single scan, simultaneously characterizing multiple aspects of physiology and function without the need for repeat imaging visits. Using dynamic imaging with staggered injections, constraints on the kinetic behavior of each tracer are applied to recover individual-tracer measures from the multi-tracer PET signal. The ability to rapidly and reliably image both 18F-fluorodeoxyglucose (FDG) and 18F-fluorothymidine (FLT) would provide complementary measures of tumor metabolism and proliferative activity, with important applications in guiding oncologic treatment decisions and assessing response. However, this tracer combination presents one of the most challenging dual-tracer signal-separation problems—both tracers have the same radioactive half-life, and the injection delay is short relative to the half-life and tracer kinetics. This work investigates techniques for single-scan dual-tracer FLT+FDG PET tumor imaging, characterizing the performance of recovering static and dynamic imaging measures for each tracer from dual-tracer datasets. Simulation studies were performed to characterize dual-tracer signal-separation performance for imaging protocols with both injection orders and injection delays of 10-60 min. Better performance was observed when FLT was administered first, and longer delays before administration of FDG provided more robust signal-separation and recovery of the single-tracer imaging measures. An injection delay of 30 min led to good recovery (R > 0.96) of static image values (e.g. SUV), Knet, and K1 as compared to values from separate, single-tracer time-activity curves. Recovery of higher order rate parameters (k2, k3) was less robust, indicating that information regarding these parameters was harder to recover in the presence of statistical noise and dual-tracer effects. Performance of the dual-tracer FLT(0 min)+FDG(32 min) technique was further evaluated using PET/CT imaging studies in

  6. Retroperitoneal bronchogenic cyst presenting paraadrenal tumor incidentally detected by 18F-FDG PET/CT

    A follow-up 18F-fluorodeoxyglucose (18F-FDG) PET/CT scan of a 57-year-old asymptomatic male who had undergone total thyroidectomy for thyroid cancer revealed a 5.0 x 4.0-cm, well-defined, ovoid-shaped mass around the left adrenal gland without definite FDG uptake. On the adrenal CT scan, the left paraadrenal tumor showed high attenuation on the precontrast scan without enhancement. The average Hounsfield unit (HU) was 58.1 on the precontrast scan and 58.4 on the postcontrast scan. The patient underwent laparoscopic adrenalectomy for resection of the left paraadrenal tumor. The final histopathologic examination revealed a bronchogenic cyst. Although retroperitoneal bronchogenic cysts are rare, they should be considered in the differential diagnosis of retroperitoneal cystic tumors. The preoperative diagnosis is difficult, but a contrast-enhanced CT scan or 18F-FDG PET/CT scan may be useful for differentiating hyperattenuated cysts from other soft tissue masses

  7. The value of 18F-FDG PET/CT in diagnosing brain metastases from unknown primary tumor

    Objective: To investigate the value of 18F-FDG PET/CT in diagnosis of brain metastases from unknown primary tumor. Method: The 18F-FDG PET/CT findings of 17 patients with brain metastases from unknown primary tumor were retrospectively analyzed. Results: Primary tumors of the seventeen cases were confirmed by biopsy, the accuracy rate was 100%. There were thirteen cases with primary lung cancer, accounted for 76%, including two cases of lung cancer which were found in the second PET/CT examination,two cases with liver cancer, accounted for 12%, one case with cardia cancer, accounted for 6%, one case with the ascending colon cancer,accounted for 6%. On the base of founding the primary tumor, 18F-FDG PET/CT also found 10 cases accompanied by lung metastasis (2 cases), lymph node metastases (3 cases), bone metastases (2 cases)and other sites of metastases (3 cases), a total of 61 lesions were detected. Two cases of liver cancer patients with single brain metastases had cerebral apoplexy. Conclusion: 18F-FDG PET/CT contributes important value in finding brain metastases from unknown primary tumor,and is very helpful for clinical staging and treatment. (authors)

  8. ImmunoPET imaging of phosphatidylserine in pro-apoptotic therapy treated tumor models

    An immunoPET imaging probe for the detection of phosphatidylserine was developed and tested in animal models of human cancer treated with pro-apoptotic therapy. We hypothesized that the relatively long plasma half-life of a probe based on a full-length antibody coupled with a residualizing radionuclide would be able to catch the wave of drug-induced apoptosis and lead to a specific accumulation in apoptotic tumor tissue. Methods: The imaging probe is based on a 89Zr-labeled monoclonal antibody PGN635 targeting phosphatidylserine. The probe was evaluated pre-clinically in four tumor xenograft models: one studied treatment with paclitaxel to trigger the intrinsic apoptotic pathway, and three others interrogated treatment with an agonistic death-receptor monoclonal antibody to engage the extrinsic apoptotic pathway. Results: High accumulation of 89Zr-PGN635 was observed in treated tumors undergoing apoptosis reaching 30 %ID/g and tumor-to-blood ratios up to 13. The tumor uptake in control groups treated with vehicle or imaged with a non-binding antibody probe was significantly lower. Conclusions: The results demonstrate the ability of 89Zr-PGN635 to image drug-induced apoptosis in animal models and corroborate our hypothesis that radiolabeled antibodies binding to intracellular targets transiently exposed on the cell surface during apoptosis can be employed for detection of tumor response to therapy.

  9. Splenosis Mimicking Relapse of a Neuroendocrine Tumor at Gallium-68-DOTATOC PET/CT

    Treglia, Giorgio; Luca, Giovanella [Oncology Institute of Southern Switzerland, Bellinzona (Switzerland); Barbara, Muoio; Carmelo, Caldarella [Catholic Univ., Rome (Italy)

    2014-06-15

    A 48-year-old female patient underwent splenopancreasectomy for a 4-cm pancreatic neuroendocrine tumor (pNET), grade G2, located in the pancreatic tail. One year after surgery, the patient presented an increased serum level of the tumor marker chromogranin A (value: 160 U/l). Therefore, she underwent somatostatin receptor PET/CT using gallium-68-DOTATOC for restaging. This imaging method showed a focal area of increased radiopharmaceutical uptake corresponding to a 2.5-cm nodule located in the left superior abdomen near a clip from the previous surgery, suggesting a possible relapse of pNET. Based on this PET/CT finding, the patient underwent ultrasonography-guided core biopsy of this nodule. Histology did not reveal findings suggestive of pNET but identified spleen tissue most likely caused by splenosis accidentally seeded at the previous operation. It is likely that the increased serum level of the tumor marker chromogranin A was due to the chronic proton-pump inhibitors use. Somatostatin receptor PET/CT is an accurate imaging method for staging and restaging pNET, presenting high sensitivity and specificity in this setting. Nevertheless, possible sources of false-negative and -positive findings with this method should be taken into account. Inflammatory lesions represent the most frequent causes of false-positive findings for pNET at somatostatin receptor imaging because inflammatory cellsmay overexpress somatostatin receptors on their cell surface. In our case, we showed that splenosis may represent a possible cause of false-positive findings for pNET relapse due to the physiological uptake of somatostatin analogs by the spleen tissue.

  10. Retroperitoneal Bronchogenic Cyst Presenting Paraadrenal Tumor Incidentally Detected by 18F-FDG PET/CT

    Yoon, Ye Ri; Choi, Jiyoun; Lee, Sang Mi; Kim, Yeo Joo; Cho, Hyun Deuk; Lee, Jeong Won; Jeon, Youn Soo

    2014-01-01

    A follow-up 18F-fluorodeoxyglucose (18F-FDG) PET/CT scan of a 57-year-old asymptomatic male who had undergone total thyroidectomy for thyroid cancer revealed a 5.0 × 4.0-cm, well-defined, ovoid-shaped mass around the left adrenal gland without definite FDG uptake. On the adrenal CT scan, the left paraadrenal tumor showed high attenuation on the precontrast scan without enhancement. The average Hounsfield unit (HU) was 58.1 on the precontrast scan and 58.4 on the postcontrast scan. The patient...

  11. Pharmacokinetic Analysis of (64)Cu-ATSM Dynamic PET in Human Xenograft Tumors in Mice

    Li, Fan; Jørgensen, Jesper Tranekjær; Madsen, Jacob; Kjaer, Andreas

    2015-01-01

    PET scans with (64)Cu-ATSM and CT scans with contrast. Irreversible and reversible two-tissue compartment models were fitted to time activity curves (TACs) obtained from whole tumor volumes and compared using the Akaike information criterion (AIC). Based on voxel-wise pharmacokinetic analysis...... early tracer uptake (mean spearman R = 0.88) 5 min post injection (pi). Moreover, positive relationships were found between late tracer uptake (90 min pi) and both k₃ and the net influx rate constant, Ki (mean spearman R = 0.56 and R = 0.86; respectively). CONCLUSION: This study shows the feasibility to...

  12. [18F]-fluoroestradiol quantitative PET imaging to differentiate ER+ and ERα-knockdown breast tumors in mice

    Introduction: The purpose of this study was to develop a noninvasive model in tumor-bearing mice to investigate the use of 16α-[18F]fluoro-17β-estradiol (FES) positron emission tomography (PET) imaging as a tool to discriminate between tumors having different estrogen receptor (ER) α status. Methods: MC7-L1 and MC4-L2 murine mammary adenocarcinoma cell lines (ER+) received a small hairpin RNA targeting the ERα gene by lentiviral infection. In vitro assessment of ERα levels of the new cell lines (MC7-L1 and MC4-L2 ERα-knockdown; ERαKD), compared to the parental cell lines, was performed by immunoblotting (−75% ERα protein) and binding assays (−50% estrogen binding). These cell lines were implanted subcutaneously in Balb/c mice and allowed to grow up to a volume of at least 20 mm3. FES and [18F]fluorodeoxyglucose (FDG) PET images were acquired to measure FES and FDG uptake in the various tumors. Results: FES uptake as assessed by PET imaging was 1.06±0.21 percent injected dose per gram of tissue (%ID/g) for MC7-L1 tumors and 0.47±0.08 %ID/g for MC7-L1 ERαKD tumors. MC4-L2 tumors had a FES uptake of 1.03±0.30 %ID/g, whereas its ERαKD equivalent was 0.51±0.19 %ID/g. Each ERαKD tumor had a significantly lower %ID/g value, by ∼50%, than its ER+ counterpart. Biodistribution studies confirmed these findings and gave %ID/g values that were not significantly different from PET imaging data. FDG PET showed no significant uptake difference between the ER+ and ERαKD tumors, indicating that the metabolic phenotype of the ERαKD cell lines was not altered. Conclusion: FES PET imaging was able to reliably differentiate between tumors having differences in their ERα expression in vivo, in a mouse model. Quantitative data obtained by FES PET were in concordance with biodistribution studies and in vitro assays. It is concluded that FES PET imaging can likely be used to monitor subtle ER status changes during the course of hormone therapy.

  13. 18F-FLT and 18F-FDOPA PET kinetics in recurrent brain tumors

    In this study, kinetic parameters of the cellular proliferation tracer 18F-3'-deoxy-3'-fluoro-l-thymidine (FLT) and the amino acid probe 3,4-dihydroxy-6-18F-fluoro-l-phenylalanine (FDOPA) were measured before and early after the start of therapy, and were used to predict the overall survival (OS) of patients with recurrent malignant glioma using multiple linear regression (MLR) analysis. High-grade recurrent brain tumors in 21 patients (11 men and 10 women, age range 26 - 76 years) were investigated. Each patient had three dynamic PET studies with each probe: at baseline and after 2 and 6 weeks from the start of treatment. Treatment consisted of biweekly cycles of bevacizumab (an angiogenesis inhibitor) and irinotecan (a chemotherapeutic agent). For each study, about 3.5 mCi of FLT (or FDOPA) was administered intravenously and dynamic PET images were acquired for 1 h (or 35 min for FDOPA). A total of 126 PET scans were analyzed. A three-compartment, two-tissue model was applied to estimate tumor FLT and FDOPA kinetic rate constants using a metabolite- and partial volume-corrected input function. MLR analysis was used to model OS as a function of FLT and FDOPA kinetic parameters for each of the three studies as well as their relative changes between studies. An exhaustive search of MLR models using three or fewer predictor variables was performed to find the best models. Kinetic parameters from FLT were more predictive of OS than those from FDOPA. The three-predictor MLR model derived using information from both probes (adjusted R2 = 0.83) fitted the OS data better than that derived using information from FDOPA alone (adjusted R2 = 0.41), but was only marginally different from that derived using information from FLT alone (adjusted R2 = 0.82). Standardized uptake values (either from FLT alone, FDOPA alone, or both together) gave inferior predictive results (best adjusted R2 = 0.25). For recurrent malignant glioma treated with bevacizumab and irinotecan, FLT kinetic

  14. 124I labeled Arg-Gly-Asp (RGD) peptide: PET/MR fusion imaging of tumor expressing integrin v3

    Tumor-induced angiogenesis and metastasis express high level of integrin v3 which has become a promising diagnostic biomarker and therapeutic target for various tumors. Radiolabeled RGD (Arg-Gly-Asp) peptides are well known to specifically bind to integrin and can be used not only for noninvasive imaging of integrin over-expression but also for integrin-targeted radionuclide therapy. We used three RGDyK derivatives, monomeric-, dimeric- and tetrameric-RGD for radio labeling. They were labeled with [124I]NaI using iodo-bead. Labeled RGD peptide was purified by FPLC. Xenografts were induced by subcutaneous injection of 1X107 U87MG cells into the right thigh of female Balb/c nude mice. After injection of 124I-labeled monomeric-RGD via the tail vein, the microPET imaging was obtained during 2 hours. Right after microPET imaging, T2-weighted MR imaging was performed with fast gradient spin echo sequence in 0.8 mm of a slice thickness. PET/MR fusion images were constructed by AMIDE program. For immobilization and reproducible positioning of animal, animal-specific positioning molds were fabricated. Monomeric-RGD peptide was labeled with 124I in labeling yield of 50%. After FPLC purification, the radiochemical purity was above 90%. U87MG tumor was clearly seen in both microPET and MR imaging of tumor-bearing nude mouse. The fusion imaging was well constructed by using AMIDE with little discrepancy thanks to animal-specific molds. Three RGD derivatives were also labeled with 131I in labeling yield of 20-55%. All three RGD peptides were successfully radioiodinated with 124I or 131I. U87MG glioblastoma tumor was clearly visualized in PET/MR fusion imaging. MicroPET/MR fusion imaging of dimeric- and tetrameric-RGD peptides in tumor bearing mice will also be presented during conference

  15. Using {sup 18F} FDG PET/CT to Detect an occult Mesenchymal Tumor Causing Oncogenic Osteomalacia

    Seo, Hyo Jung; Choi, Yun Jung; Kim, Hyun Jeong; Jeong, Yong Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Lee, Jong Doo; Kang, Won Jun [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    2011-09-15

    Oncogenic osteomalacia is a rare paraneoplastic syndrome characterized by renal phosphate excretion, hypophosphatemia, and osteomalacia. This syndrome is often caused by tumors of mesenchymal origin. Patients with oncogenic osteomalacia have abnormal bone mineralization, resulting in a high frequency of fractures. Tumor resection is the treatment of choice, as it will often correct the metabolic imbalance. Although oncogenic osteomalacia is a potentially curable disease, diagnosis is difficult and often delayed because of the small size and sporadic location of the tumor. Bone scintigraphy and radiography best characterize osteoma lacia; magnetic resonance imaging findings are nonspecific. Here, we report a case of oncogenic osteomalacia secondary to a phosphaturic mesenchymal tumor that was successfully detected by {sup 18F} fluorodeoxyglucose positron emission tomography/computed tomography ({sup 18F} FDG PET/CT). This case illustrates the advantages of {sup 18F} FDG PET/CT in detecting the occult mesenchymal tumor that causes oncogenic osteomalacia.

  16. 18F-EF5 PET Is Predictive of Response to Fractionated Radiotherapy in Preclinical Tumor Models

    Rehan Ali; Sandeep Apte; Marta Vilalta; Murugesan Subbarayan; Zheng Miao; Chin, Frederick T.; Graves, Edward E.

    2015-01-01

    We evaluated the relationship between pre-treatment positron emission tomography (PET) using the hypoxic tracer 18F-[2-(2-nitro-1-H-imidazol-1-yl)-N-(2,2,3,3,3- pentafluoropropyl) acetamide] (18F-EF5) and the response of preclinical tumor models to a range of fractionated radiotherapies. Subcutaneous HT29, A549 and RKO tumors grown in nude mice were imaged using 18F-EF5 positron emission tomography (PET) in order to characterize the extent and heterogeneity of hypoxia in these systems. Based ...

  17. Comparative study of 18F-DOPA, 13N-Ammonia and F18-FDG PET/CT in primary brain tumors

    Jacob, Mattakarottu J; Pandit, Aniruddha G; Jora, Charu; Mudalsha, Ravina; Sharma, Amit; Pathak, Harish C

    2011-01-01

    Aim: To determine the diagnostic reliability of 18F-FDOPA, 13N-Ammonia and F18-FDG PET/CT in primary brain tumors. We evaluated the amino acid and glucose metabolism of brain tumors by using PET with 18F-FDOPA, 13N-Ammonia and F18-FDG PET/CT. Materials and Methods: Nine patients undergoing evaluation for brain tumors were studied. Tracer uptake was quantified by the use of standardized uptake values and the ratio of tumor uptake to normal identical area of contra lateral hemisphere (T/N). In addition, PET uptake with 18F-FDOPA was quantified by use of ratio of tumor uptake to striatum uptake (T/S). The results were correlated with the patient's clinical profile. Results: Both high-grade and low-grade tumors were well visualized with 18F-FDOPA. The sensitivity for identifying tumors was substantially higher with 18F-FDOPA PET than with F18-FDG and 13N-Ammonia PET as determined by simple visual inspection. The sensitivity for identifying recurrence in low grade gliomas is higher with 13N-Ammonia than with F18-FDG. Conclusion: 18F-FDOPA PET is more reliable than F18-FDG and 13N-Ammonia PET for evaluating brain tumors. PMID:23326065

  18. Comparative study of 18F-DOPA, 13 N-ammonia and 18F-FDG PET/CT in primary brain tumors

    To determine the diagnostic reliability of 18F-FDOPA, 13N-ammonia and 18F-FDG PET/CT in primary brain tumors. We evaluated the amino acid and glucose metabolism of brain tumors by using PET with 18F-FDOPA, 13N-ammonia and 18F-FDG PET/CT. Nine patients undergoing evaluation for brain tumors were studied. Tracer uptake was quantified by the use of standardized uptake values and the ratio of tumor uptake to normal identical area of contra lateral hemisphere (T/N). In addition, PET uptake with 18F-FDOPA was quantified by use of ratio of tumor uptake to striatum uptake (T/S). The results were correlated with the patient's clinical profile. Both high-grade and low-grade tumors were well visualized with 18F-FDOPA. The sensitivity for identifying tumors was substantially higher with 18F-FDOPA PET than with 18F-FDG and 13N-Ammonia PET as determined by simple visual inspection. The sensitivity for identifying recurrence in low grade gliomas is higher with 13N-Ammonia than with 18F-FDG. 18F-FDOPA PET is more reliable than 18F-FDG and 13N-Ammonia PET for evaluating brain tumors. (author)

  19. Correlation of PET images of metabolism, proliferation and hypoxia to characterize tumor phenotype in patients with cancer of the oropharynx

    Spatial organization of tumor phenotype is of great interest to radiotherapy target definition and outcome prediction. We characterized tumor phenotype in patients with cancers of the oropharynx through voxel-based correlation of PET images of metabolism, proliferation, and hypoxia. Methods: Patients with oropharyngeal cancer received 18F-fluorodeoxyglucose (FDG) PET/CT, 18F-fluorothymidine (FLT) PET/CT, and 61Cu-diacetyl-bis(N4-methylthiosemicarbazone) (Cu-ATSM) PET/CT. Images were co-registered and standardized uptake values (SUV) were calculated for all modalities. Voxel-based correlation was evaluated with Pearson’s correlation coefficient in tumor regions. Additionally, sensitivity studies were performed to quantify the effects of image segmentation, registration, noise, and segmentation on R. Results: On average, FDG PET and FLT PET images were most highly correlated (RFDG:FLT = 0.76, range 0.53–0.85), while Cu-ATSM PET showed greater heterogeneity in correlation to other tracers (RFDG:Cu-ATSM = 0.64, range 0.51–0.79; RFLT:Cu-ATSM = 0.61, range 0.21–0.80). Of the tested parameters, correlation was most sensitive to image registration. Misregistration of one voxel lead to ΔRFDG = 0.25, ΔRFLT = 0.39, and ΔRCu-ATSM = 0.27. Image noise and reconstruction also had quantitative effects on correlation. No significant quantitative differences were found between GTV, expanded GTV, or CTV regions. Conclusions: Voxel-based correlation represents a first step into understanding spatial organization of tumor phenotype. These results have implications for radiotherapy target definition and provide a framework to test outcome prediction based on pretherapy distribution of phenotype.

  20. Impact of Anatomical Location on Value of CT-PET Co-Registration for Delineation of Lung Tumors

    Purpose: To derive guidelines for the need to use positron emission tomography (PET) for delineation of the primary tumor (PT) according to its anatomical location in the lung. Methods and Materials: In 22 patients with non-small-cell lung cancer, thoracic X-ray computed tomography (CT) and PET were performed. Eleven radiation oncologists delineated the PT on the CT and on the CT-PET registered scans. The PTs were classified into two groups. In Group I patients, the PT was surrounded by lung or visceral pleura, without venous invasion, without extension to chest wall or the mediastinum over more than one quarter of its surface. In Group II patients, the PT invaded the hilar region, heart, great vessels, pericardium, mediastinum over more than one quarter of its surface and/or associated with atelectasis. A comparison of interobserver variability for each group was performed and expressed as a local standard deviation. Results: The comparison of delineations showed a good reproducibility for Group I, with an average SD of 0.4 cm on CT and an average SD of 0.3 cm on CT-PET (p = 0.1628). There was also a significant improvement with CT-PET for Group II, with an average SD of 1.3 cm on CT and SD of 0.4 cm on CT-PET (p = 0.0003). The improvement was mainly located at the atelectasis/tumor interface. At the tumor/lung and tumor/hilum interfaces, the observer variation was similar with both modalities. Conclusions: Using PET for PT delineation is mandatory to decrease interobserver variability in the hilar region, heart, great vessels, pericardium, mediastinum, and/or the region associated with atelectasis; however it is not essential for delineation of PT surrounded by lung or visceral pleura, without venous invasion or extension to the chest wall

  1. Folic acid derivatives for PET imaging and therapy addressing folate receptor positive tumors

    Folic acid, also known as vitamin B9, is the oxidized form of 5,6,7,8-tetrahydrofolate, which serves as methyl- or methylene donor (C1-building blocks) during DNA synthesis. Under physiological conditions the required amount of 5,6,7,8-tetrahydrofolate for survival of the cell is accomplished through the reduced folate carrier (RFC). In contrast, the supply of 5,6,7,8-tetrahydrofolate is insufficient under pathophysiological conditions of tumors due to an increased proliferation rate. Consequently, many tumor cells exhibit an (over)expression of the folate receptor. This phenomenon has been applied to diagnostics (PET, SPECT, MR) to image FR-positive tumors and on the other hand to treat malignancies related to a FR (over)expression. Based on this concept, a new 18F-labeled folate for PET imaging has been developed and was evaluated in vivo using tumor-bearing mice. The incorporation of oligoethylene spacers into the molecular structure led to a significant enhancement of the pharmacokinetics in comparison to previously developed 18F-folates. The liver uptake could be reduced by one sixth by remaining a tumor uptake of 3%ID/g leading to better contrast ratios. Encouraged by these results, a clickable 18F-labeled serine-based prosthetic group has been synthesized, again with the idea to improve the metabolic and pharmacokinetic profile of hydrophilic radiotracers. Therefore, an alkyne-carrying azido-functionalized serine derivative for coupling to biomolecules was synthesized and a chlorine leaving group for 18F-labeling, which could be accomplished using a microwave-assisted synthesis, a [K is contained in 2.2.2]+/carbonate system in DMSO. Radiochemical yields of 77±6% could be achieved. The promising results obtained from the FR-targeting concept in the diagnostic field have been transferred to the boron neutron capture therapy. Therefore, a folate derivative was coupled to different boron clusters and cell uptake studies were conducted. The synthesis of the

  2. Folic acid derivatives for PET imaging and therapy addressing folate receptor positive tumors

    Schieferstein, Hanno

    2013-07-01

    Folic acid, also known as vitamin B9, is the oxidized form of 5,6,7,8-tetrahydrofolate, which serves as methyl- or methylene donor (C1-building blocks) during DNA synthesis. Under physiological conditions the required amount of 5,6,7,8-tetrahydrofolate for survival of the cell is accomplished through the reduced folate carrier (RFC). In contrast, the supply of 5,6,7,8-tetrahydrofolate is insufficient under pathophysiological conditions of tumors due to an increased proliferation rate. Consequently, many tumor cells exhibit an (over)expression of the folate receptor. This phenomenon has been applied to diagnostics (PET, SPECT, MR) to image FR-positive tumors and on the other hand to treat malignancies related to a FR (over)expression. Based on this concept, a new {sup 18}F-labeled folate for PET imaging has been developed and was evaluated in vivo using tumor-bearing mice. The incorporation of oligoethylene spacers into the molecular structure led to a significant enhancement of the pharmacokinetics in comparison to previously developed {sup 18}F-folates. The liver uptake could be reduced by one sixth by remaining a tumor uptake of 3%ID/g leading to better contrast ratios. Encouraged by these results, a clickable {sup 18}F-labeled serine-based prosthetic group has been synthesized, again with the idea to improve the metabolic and pharmacokinetic profile of hydrophilic radiotracers. Therefore, an alkyne-carrying azido-functionalized serine derivative for coupling to biomolecules was synthesized and a chlorine leaving group for {sup 18}F-labeling, which could be accomplished using a microwave-assisted synthesis, a [K is contained in 2.2.2]{sup +}/carbonate system in DMSO. Radiochemical yields of 77±6% could be achieved. The promising results obtained from the FR-targeting concept in the diagnostic field have been transferred to the boron neutron capture therapy. Therefore, a folate derivative was coupled to different boron clusters and cell uptake studies were

  3. Early Detection of Tumor Response by FLT/MicroPET Imaging in a C26 Murine Colon Carcinoma Solid Tumor Animal Model

    Wan-Chi Lee

    2011-01-01

    Full Text Available Fluorine-18 fluorodeoxyglucose (18F-FDG positron emission tomography (PET imaging demonstrated the change of glucose consumption of tumor cells, but problems with specificity and difficulties in early detection of tumor response to chemotherapy have led to the development of new PET tracers. Fluorine-18-fluorothymidine (18F-FLT images cellular proliferation by entering the salvage pathway of DNA synthesis. In this study, we evaluate the early response of colon carcinoma to the chemotherapeutic drug, lipo-Dox, in C26 murine colorectal carcinoma-bearing mice by 18F-FDG and 18F-FLT. The male BALB/c mice were bilaterally inoculated with 1×105 and 1×106 C26 tumor cells per flank. Mice were intravenously treated with 10 mg/kg lipo-Dox at day 8 after 18F-FDG and 18F-FLT imaging. The biodistribution of 18F-FDG and 18F-FLT were followed by the microPET imaging at day 9. For the quantitative measurement of microPET imaging at day 9, 18F-FLT was superior to 18F-FDG for early detection of tumor response to Lipo-DOX at various tumor sizes (<0.05. The data of biodistribution showed similar results with those from the quantification of SUV (standard uptake value by microPET imaging. The study indicates that 18F-FLT/microPET is a useful imaging modality for early detection of chemotherapy in the colorectal mouse model.

  4. Pathological validation of FLT PET-CT in delineating the biological target length of gross tumor in esophageal carcinoma

    Objective: To establish a optimal method and threshold of 3-deoxy-3-fluoro thymidine (FLT) PET-CT in delineating the biological target length of gross tumor in esophageal carcinoma, and to compare FLT PET-CT with other imaging modalities including esophagoscopy, esophagography, CT and fluorodeoxyglucose (FDG) PET-CT. Methods: Twenty-four patients with esophageal squamous cell carcinoma treated with radical surgery were enrolled. Before surgery, all the patients underwent FLT PET-CT, esephagoscopy and esophagography. Twenty-two patients also received FDG PET-CT scan. Gross tumor volumes (GTV) were delineated using seven different threshold of FLT PET-CT: visual interpretation, standardized uptake value (SUV) 1.3, SUV 1.4, SUV 1.5, 20% of maximum standard uptake value (SUVmax), 25% SUVmax, and 30% SUVmax. Three different thresholds of FDG PET-CT were used, including visual interpretation, SUV 2.5, and 40% SUVmax. The length of tumors on FLT PET-CT scan were measured and recorded as LFLTvis, LFLT1.3, LFLT1.4, LFLT1.5, LFLT20%, LFLT25%, and LFLT30%, respectively. The length of tumors on FDG PET-CT scan were recorded as LFDGvis, LFDG2.5, and LFDG40%, respectively. The length of tumors on CT, esophagography and esophagoscopy were recorded as LCT, LX-ray and LScopy. All of these results were com-pared with the length of gross tumor in the reseated specimen measured by pathological examination (LPath). Results: The LPath was (4.90±2.14) cm. The Length of tumors delineated by different methods, being from short to long, were LFDG40%, LScopy, LX-ray, LFLT1.5, LCT, LFLT30%, LFLTvis, LFLT1.4, LFLT25%, LFDG2.5, LFDGvis, LFLT1.3, LFLT20%. The mean values were (3.85±1.52), (4.46±2.23), (4.63±2.37), (4.64±2.38), (4.69±31.85), (4.75±2.19), (4.85±2.33), (4.87±2.35), (5.05±2.20), (5.08±2.19), (5.10±2.22), (5.21±2.40) and (5.53±2.17) cm,respectively. The correlation coefficients were 0.91, 0.93, 0.88, 0.95, 0.90, 0.81, 0.96, 0.96, 0.80, 0.99, 0.99, 0.95 and 0

  5. The value of {sup 18}F-FDG PET/CT in the management of malignant peripheral nerve sheath tumors

    Khiewvan, Benjapa [University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States); Mahidol University, Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine Siriraj Hospital, Bangkok (Thailand); Macapinlac, Homer A.; Chuang, Hubert H. [University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States); Lev, Dina; Al Sannaa, Ghadah [University of Texas MD Anderson Cancer Center, Department of Cancer Biology, Houston, TX (United States); McCutcheon, Ian E. [University of Texas MD Anderson Cancer Center, Department of Neurosurgery, Houston, TX (United States); Slopis, John M. [University of Texas MD Anderson Cancer Center, Department of Neuro-Oncology, Houston, TX (United States); Wei, Wei [University of Texas MD Anderson Cancer Center, Department of Biostatistics, Houston, TX (United States)

    2014-09-15

    Our objective was to determine how positron emission tomography (PET)/CT had been used in the clinical treatment of malignant peripheral nerve sheath tumor (MPNST) patients at The University of Texas MD Anderson Cancer Center. We reviewed a database of MPNST patients referred to MD Anderson Cancer Center during 1995-2011. We enrolled 47 patients who underwent PET/CT imaging. Disease stage was based on conventional imaging and PET/CT findings using National Comprehensive Cancer Network (NCCN) guidelines. Treatment strategies based on PET/CT and conventional imaging were determined by chart review. The maximum and mean standardized uptake values (SUV{sub max}, SUV{sub mean}), metabolic tumor volume (MTV), total lesion glycolysis (TLG), change in SUV{sub max}, change in MTV, and change in TLG were calculated from the PET/CT studies before and after treatment. Response prediction was based on imaging studies performed before and after therapy and categorized as positive or negative for residual tumor. Clinical outcome was determined from chart review. PET/CT was performed for staging in 16 patients, for restaging in 29 patients, and for surveillance in 2 patients. Of the patients, 88 % were correctly staged with PET/CT, whereas 75 % were correctly staged with conventional imaging. The sensitivity to detect local recurrence and distant metastasis at restaging was 100 and 100 % for PET/CT compared to 86 and 83 % for conventional imaging, respectively. PET/CT findings resulted in treatment changes in 31 % (5/16) and 14 % (4/29) of patients at staging and restaging, respectively. Recurrence, MTV, and TLG were prognostic factors for survival, whereas SUV{sub max} and SUV{sub mean} were not predictive. For 21 patients who had imaging studies performed both before and after treatment, PET/CT was better at predicting outcome (overall survival, progression-free survival) than conventional imaging. A decreasing SUV{sub max} ≥ 30 % and decrease in TLG and MTV were significant

  6. The value of 18F-FDG PET/CT in the management of malignant peripheral nerve sheath tumors

    Our objective was to determine how positron emission tomography (PET)/CT had been used in the clinical treatment of malignant peripheral nerve sheath tumor (MPNST) patients at The University of Texas MD Anderson Cancer Center. We reviewed a database of MPNST patients referred to MD Anderson Cancer Center during 1995-2011. We enrolled 47 patients who underwent PET/CT imaging. Disease stage was based on conventional imaging and PET/CT findings using National Comprehensive Cancer Network (NCCN) guidelines. Treatment strategies based on PET/CT and conventional imaging were determined by chart review. The maximum and mean standardized uptake values (SUVmax, SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG), change in SUVmax, change in MTV, and change in TLG were calculated from the PET/CT studies before and after treatment. Response prediction was based on imaging studies performed before and after therapy and categorized as positive or negative for residual tumor. Clinical outcome was determined from chart review. PET/CT was performed for staging in 16 patients, for restaging in 29 patients, and for surveillance in 2 patients. Of the patients, 88 % were correctly staged with PET/CT, whereas 75 % were correctly staged with conventional imaging. The sensitivity to detect local recurrence and distant metastasis at restaging was 100 and 100 % for PET/CT compared to 86 and 83 % for conventional imaging, respectively. PET/CT findings resulted in treatment changes in 31 % (5/16) and 14 % (4/29) of patients at staging and restaging, respectively. Recurrence, MTV, and TLG were prognostic factors for survival, whereas SUVmax and SUVmean were not predictive. For 21 patients who had imaging studies performed both before and after treatment, PET/CT was better at predicting outcome (overall survival, progression-free survival) than conventional imaging. A decreasing SUVmax ≥ 30 % and decrease in TLG and MTV were significant predictors for overall and

  7. Predicting location of recurrence using FDG, FLT, and Cu-ATSM PET in canine sinonasal tumors treated with radiotherapy

    Dose painting relies on the ability of functional imaging to identify resistant tumor subvolumes to be targeted for additional boosting. This work assessed the ability of FDG, FLT, and Cu-ATSM PET imaging to predict the locations of residual FDG PET in canine tumors following radiotherapy. Nineteen canines with spontaneous sinonasal tumors underwent PET/CT imaging with radiotracers FDG, FLT, and Cu-ATSM prior to hypofractionated radiotherapy. Therapy consisted of 10 fractions of 4.2 Gy to the sinonasal cavity with or without an integrated boost of 0.8 Gy to the GTV. Patients had an additional FLT PET/CT scan after fraction 2, a Cu-ATSM PET/CT scan after fraction 3, and follow-up FDG PET/CT scans after radiotherapy. Following image registration, simple and multiple linear and logistic voxel regressions were performed to assess how well pre- and mid-treatment PET imaging predicted post-treatment FDG uptake. R2 and pseudo R2 were used to assess the goodness of fits. For simple linear regression models, regression coefficients for all pre- and mid-treatment PET images were significantly positive across the population (P < 0.05). However, there was large variability among patients in goodness of fits: R2 ranged from 0.00 to 0.85, with a median of 0.12. Results for logistic regression models were similar. Multiple linear regression models resulted in better fits (median R2 = 0.31), but there was still large variability between patients in R2. The R2 from regression models for different predictor variables were highly correlated across patients (R ≈ 0.8), indicating tumors that were poorly predicted with one tracer were also poorly predicted by other tracers. In conclusion, the high inter-patient variability in goodness of fits indicates that PET was able to predict locations of residual tumor in some patients, but not others. This suggests not all patients would be good candidates for dose painting based on a single biological target. (paper)

  8. Predicting location of recurrence using FDG, FLT, and Cu-ATSM PET in canine sinonasal tumors treated with radiotherapy

    Bradshaw, Tyler; Fu, Rau; Bowen, Stephen; Zhu, Jun; Forrest, Lisa; Jeraj, Robert

    2015-07-01

    Dose painting relies on the ability of functional imaging to identify resistant tumor subvolumes to be targeted for additional boosting. This work assessed the ability of FDG, FLT, and Cu-ATSM PET imaging to predict the locations of residual FDG PET in canine tumors following radiotherapy. Nineteen canines with spontaneous sinonasal tumors underwent PET/CT imaging with radiotracers FDG, FLT, and Cu-ATSM prior to hypofractionated radiotherapy. Therapy consisted of 10 fractions of 4.2 Gy to the sinonasal cavity with or without an integrated boost of 0.8 Gy to the GTV. Patients had an additional FLT PET/CT scan after fraction 2, a Cu-ATSM PET/CT scan after fraction 3, and follow-up FDG PET/CT scans after radiotherapy. Following image registration, simple and multiple linear and logistic voxel regressions were performed to assess how well pre- and mid-treatment PET imaging predicted post-treatment FDG uptake. R2 and pseudo R2 were used to assess the goodness of fits. For simple linear regression models, regression coefficients for all pre- and mid-treatment PET images were significantly positive across the population (P < 0.05). However, there was large variability among patients in goodness of fits: R2 ranged from 0.00 to 0.85, with a median of 0.12. Results for logistic regression models were similar. Multiple linear regression models resulted in better fits (median R2 = 0.31), but there was still large variability between patients in R2. The R2 from regression models for different predictor variables were highly correlated across patients (R ≈ 0.8), indicating tumors that were poorly predicted with one tracer were also poorly predicted by other tracers. In conclusion, the high inter-patient variability in goodness of fits indicates that PET was able to predict locations of residual tumor in some patients, but not others. This suggests not all patients would be good candidates for dose painting based on a single biological target.

  9. Analysis of pairwise correlations in multi-parametric PET/MR data for biological tumor characterization and treatment individualization strategies

    The aim of this pilot study was to explore simultaneous functional PET/MR for biological characterization of tumors and potential future treatment adaptations. To investigate the extent of complementarity between different PET/MR-based functional datasets, a pairwise correlation analysis was performed. Functional datasets of N=15 head and neck (HN) cancer patients were evaluated. For patients of group A (N=7), combined PET/MR datasets including FDG-PET and ADC maps were available. Patients of group B (N=8) had FMISO-PET, DCE-MRI and ADC maps from combined PET/MRI, an additional dynamic FMISO-PET/CT acquired directly after FMISO tracer injection as well as an FDG-PET/CT acquired a few days earlier. From DCE-MR, parameter maps Ktrans, ve and vp were obtained with the extended Tofts model. Moreover, parameter maps of mean DCE enhancement, ΔSDCE, and mean FMISO signal 0-4 min p.i., anti AFMISO, were derived. Pairwise correlations were quantified using the Spearman correlation coefficient (r) on both a voxel and a regional level within the gross tumor volume. Between some pairs of functional imaging modalities moderate correlations were observed with respect to the median over all patient datasets, whereas distinct correlations were only present on an individual basis. Highest inter-modality median correlations on the voxel level were obtained for FDG/FMISO (r = 0.56), FDG/ anti AFMISO (r = 0.55), anti AFMISO/ΔSDCE (r = 0.46), and FDG/ADC (r = -0.39). Correlations on the regional level showed comparable results. The results of this study suggest that the examined functional datasets provide complementary information. However, only pairwise correlations were examined, and correlations could still exist between combinations of three or more datasets. These results might contribute to the future design of individually adapted treatment approaches based on multiparametric functional imaging.

  10. Anesthesia condition for {sup 18}F-FDG imaging of lung metastasis tumors using small animal PET

    Woo, Sang-Keun; Lee, Tae Sup; Kim, Kyeong Min; Kim, June-Youp; Jung, Jae Ho; Kang, Joo Hyun [Division of Nuclear Medicine and RI Application, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of); Cheon, Gi Jeong [Division of Nuclear Medicine and RI Application, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of); Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of)], E-mail: larry@kcch.re.kr; Choi, Chang Woon; Lim, Sang Moo [Division of Nuclear Medicine and RI Application, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of); Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of)

    2008-01-15

    Small animal positron emission tomography (PET) with {sup 18}F-FDG has been increasingly used for tumor imaging in the murine model. The aim of this study was to establish the anesthesia condition for imaging of lung metastasis tumor using small animal {sup 18}F-FDG PET. Methods: To determine the impact of anesthesia on {sup 18}F-FDG distribution in normal mice, five groups were studied under the following conditions: no anesthesia, ketamine and xylazine (Ke/Xy), 0.5% isoflurane (Iso 0.5), 1% isoflurane (Iso 1) and 2% isoflurane (Iso 2). The ex vivo counting, standard uptake value (SUV) image and glucose SUV of {sup 18}F-FDG in various tissues were evaluated. The {sup 18}F-FDG images in the lung metastasis tumor model were obtained under no anesthesia, Ke/Xy and Iso 0.5, and registered with CT image to clarify the tumor region. Results: Blood glucose concentration and muscle uptake of {sup 18}F-FDG in the Ke/Xy group markedly increased more than in the other groups. The Iso 2 group increased {sup 18}F-FDG uptake in heart compared with the other groups. The Iso 0.5 anesthesized group showed the lowest {sup 18}F-FDG uptake in heart and chest wall. The small size of lung metastasis tumor (2 mm) was clearly visualized by {sup 18}F-FDG image with the Iso 0.5 anesthesia. Conclusion: Small animal {sup 18}F-FDG PET imaging with Iso 0.5 anesthesia was appropriate for the detection of lung metastasis tumor. To acquire {sup 18}F-FDG PET images with small animal PET, the type and level of anesthetic should be carefully considered to be suitable for the visualization of target tissue in the experimental model.

  11. Breast PET scan

    Breast positron emission tomography; PET - breast; PET - tumor imaging - breast ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), usually ...

  12. Tumor necrosis at FDG-PET is an independent predictor of outcome in diffuse large B-cell lymphoma

    Adams, Hugo J A; De Klerk, John M H; Fijnheer, Rob; Heggelman, Ben G F; Dubois, Stefan V.; Nievelstein, Rutger A J; Kwee, Thomas C.

    2016-01-01

    Purpose To determine the prognostic performance of tumor necrosis at FDG-PET in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL) who are treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy. Materials and methods 108 patients with new

  13. Assessment of [18F]-fluoroacetate PET/CT as a tumor-imaging modality. Preclinical study in healthy volunteers and clinical evaluation in patients with liver tumor

    Although [18F]-FDG is a useful oncologic PET tracer, FDG uptake is known to be low in a certain type of hepatocellular carcinoma (HCC). [18F]-fluoroacetate (18F-FACE) is an [18F] fluorinated acetate, which is known to be converted into fatty acids, incorporated in membrane and is expected to be a promising oncologic PET tracer. The aim of this study was to evaluate the usefulness of 18F-FACE as an oncologic PET tracer in preclinical study in healthy volunteers and in patients with liver tumors. Twenty-four healthy volunteers (age 48.2 ± 12.9 years old; 15 male and 9 female) and ten patients with liver tumor (age 72.1 ± 7.0 years old; 6 male and 4 female) were included. We performed whole-body static PET/CT scan using 18F-FACE (n=34) and 18F-FDG (n=5 for volunteers, n=8 for patients) on each day, respectively. Qualitative analysis and quantitative analysis of tumors (5 HCCs, 1 cholangiocellular carcinoma, 4 metastatic tumors from colon cancer and P-NET) were performed using SUVmax and tumor-to-normal liver ratio (TNR). In healthy volunteers, 18F-FACE was metabolically stable in vivo and its biodistribution was almost similar to blood pool, basically uniformly independent of age and gender during PET scan time (up to 3 h). Normal physiological uptake of 18F-FACE at each organ including liver (SUVmean 1.8 ± 0.2) was lower than that of blood pool (SUVmean 2.3 ± 0.3) at 1 h after injection. Chronic inflammatory uptake around femur of post-operative state of femoral osteotomy and faint uptake of benign hemangioma were observed in a case of healthy volunteer. 18F-FACE (SUVmax 2.7 ± 0.6, TNR 1.5 ± 0.4) of liver tumors was significantly lower than those of 18F-FDG uptake (6.5 ± 4.2, 2.6 ± 1.7, respectively). In qualitative analysis, 18F-FDG was positive in 4 tumors (3 HCCs, 1 CCC) and negative in the other 6 tumors, while 18F-FACE was also positive in 4 tumors which were the same tumors with positive 18F-FDG uptake. Biodistribution of 18F-FACE was appropriate for

  14. Differentiation between low potential malignancy and ovarian cancer, benign ovarian tumor using FDG PET/CT in comparison with MRI

    We evaluated the usefulness of fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT for differentiation between ovarian tumors in comparison with MRI. Seventeen women who had ovarian tumors histologically proven were studied. There were 6 ovarian cancers, 6 low potential malignancys (LPMs), and 5 benign tumors. PET/CT was performed early scan at 1 hour and delayed scan at 2 hours after administration of FDG. FDG uptake was seen in the solid portion of tumors on MRI. Early and delayed standardized uptake value (SUV)max on solid portion of LPMs were significantly lower than those of cancers and were also lower than those of benign tumors. The delayed SUVmax of cancers was significantly higher than early SUVmax, while there was no significant difference between early and delayed SUVmax of LPMs. It is important differential diagnosis of ovarian tumors, because operation procedure for LPM is different from cancer. Our results suggest that FDG PET/CT is useful for differentiation LPMs from ovarian cancers, but further investigation is needed. (author)

  15. Radiolabelling and evaluation of a novel sulfoxide as a PET imaging agent for tumor hypoxia

    [18F]FMISO is the most widely validated PET radiotracer for imaging hypoxic tissue. However, as a result of the pharmacokinetics of [18F]FMISO a 2 h wait between tracer administration and patient scanning is required for optimal image acquisition. In order to develop hypoxia imaging agents with faster kinetics, we have synthesised and evaluated several F-18 labelled anilino sulfoxides. In this manuscript we report on the synthesis, in vitro and in vivo evaluation of a novel fluoroethyltriazolyl propargyl anilino sulfoxide. The radiolabelling of the novel tracer was achieved via 2-[18F]fluoroethyl azide click chemistry. Radiochemical yields were 23 ± 4% based on 2-[18F]fluoroethyl azide and 7 ± 2% based on K[18F]F. The radiotracer did not undergo metabolism or defluorination in an in vitro assay using S9 liver fractions. Imaging studies using SK-RC-52 tumors in BALB/c nude mice have indicated that the tracer may have a higher pO2 threshold than [18F]FMISO for uptake in hypoxic tumors. Although clearance from muscle was faster than [18F]FMISO, uptake in hypoxic tumors was slower. The average tumor to muscle ratio at 2 h post injection in large, hypoxic tumors with a volume greater than 686 mm3 was 1.7, which was similar to the observed ratio of 1.75 for [18F]FMISO. Although the new tracer showed improved pharmacokinetics when compared with the previously synthesised sulfoxides, further modifications to the chemical structure need to be made in order to offer significant in vivo imaging advantages over [18F]FMISO

  16. FDG-avid portal vein tumor thrombosis from hepatocellular carcinoma in contrast-enhanced FDG PET/CT

    Canh Nguyen

    2015-01-01

    Full Text Available Objective(s: In this study, we aimed to describe the characteristics of portal vein tumor thrombosis (PVTT, complicating hepatocellular carcinoma (HCC in contrast-enhanced FDG PET/CT scan. Methods: In this retrospective study, 9 HCC patients with FDG-avid PVTT were diagnosed by contrast-enhanced fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT, which is a combination of dynamic liver CT scan, multiphase imaging, and whole-body PET scan. PET and CT DICOM images of patients were imported into the PET/CT imaging system for the re-analysis of contrast enhancement and FDG uptake in thrombus, the diameter of the involved portal vein, and characteristics of liver tumors and metastasis. Results: Two patients with previously untreated HCC and 7 cases with previously treated HCC had FDG-avid PVTT in contrast-enhanced FDG PET/CT scan. During the arterial phase of CT scan, portal vein thrombus showed contrast enhancement in 8 out of 9 patients (88.9%. PET scan showed an increased linear FDG uptake along the thrombosed portal vein in all patients. The mean greatest diameter of thrombosed portal veins was 1.8 ± 0.2 cm, which was significantly greater than that observed in normal portal veins (P<0.001. FDG uptake level in portal vein thrombus was significantly higher than that of blood pool in the reference normal portal vein (P=0.001. PVTT was caused by the direct extension of liver tumors. All patients had visible FDG-avid liver tumors in contrast-enhanced images. Five out of 9 patients (55.6% had no extrahepatic metastasis, 3 cases (33.3% had metastasis of regional lymph nodes, and 1 case (11.1% presented with distant metastasis. The median estimated survival time of patients was 5 months. Conclusion: The intraluminal filling defect consistent with thrombous within the portal vein, expansion of the involved portal vein, contrast enhancement, and linear increased FDG uptake of the thrombus extended from liver tumor are

  17. Analysis of Pretreatment FDG-PET SUV Parameters in Head-and-Neck Cancer: Tumor SUVmean Has Superior Prognostic Value

    Purpose: To evaluate the prognostic significance of different descriptive parameters in head-and-neck cancer patients undergoing pretreatment [F-18] fluoro-D-glucose-positron emission tomography (FDG-PET) imaging. Patients and Methods: Head-and-neck cancer patients who underwent FDG-PET before a course of curative intent radiotherapy were retrospectively analyzed. FDG-PET imaging parameters included maximum (SUVmax), and mean (SUVmean) standard uptake values, and total lesion glycolysis (TLG). Tumors and lymph nodes were defined on co-registered axial computed tomography (CT) slices. SUVmax and SUVmean were measured within these anatomic regions. The relationships between pretreatment SUVmax, SUVmean, and TLG for the primary site and lymph nodes were assessed using a univariate analysis for disease-free survival (DFS), locoregional control (LRC), and distant metastasis-free survival (DMFS). Kaplan-Meier survival curves were generated and compared via the log‒rank method. SUV data were analyzed as continuous variables. Results: A total of 88 patients was assessed. Two-year OS, LRC, DMFS, and DFS for the entire cohort were 85%, 78%, 81%, and 70%, respectively. Median SUVmax for the primary tumor and lymph nodes was 15.4 and 12.2, respectively. Median SUVmean for the primary tumor and lymph nodes was 7 and 5.2, respectively. Median TLG was 770. Increasing pretreatment SUVmean of the primary tumor was associated with decreased disease-free survival (p = 0.01). Neither SUVmax in the primary tumor or lymph nodes nor TLG was prognostic for any of the clinical endpoints. Patients with pretreatment tumor SUVmean that exceeded the median value (7) of the cohort demonstrated inferior 2-year DFS relative to patients with SUVmean ≤ the median value of the cohort, 58% vs. 82%, respectively, p = 0.03. Conclusion: Increasing SUVmean in the primary tumor was associated with inferior DFS. Although not routinely reported, pretreatment SUVmean may be a useful prognostic FDG-PET

  18. SPEQTACLE: An automated generalized fuzzy C-means algorithm for tumor delineation in PET

    Lapuyade-Lahorgue, Jérôme; Visvikis, Dimitris; Hatt, Mathieu, E-mail: hatt@univ-brest.fr [LaTIM, INSERM, UMR 1101, Brest 29609 (France); Pradier, Olivier [LaTIM, INSERM, UMR 1101, Brest 29609, France and Radiotherapy Department, CHRU Morvan, Brest 29609 (France); Cheze Le Rest, Catherine [DACTIM University of Poitiers, Nuclear Medicine Department, CHU Milétrie, Poitiers 86021 (France)

    2015-10-15

    Purpose: Accurate tumor delineation in positron emission tomography (PET) images is crucial in oncology. Although recent methods achieved good results, there is still room for improvement regarding tumors with complex shapes, low signal-to-noise ratio, and high levels of uptake heterogeneity. Methods: The authors developed and evaluated an original clustering-based method called spatial positron emission quantification of tumor—Automatic Lp-norm estimation (SPEQTACLE), based on the fuzzy C-means (FCM) algorithm with a generalization exploiting a Hilbertian norm to more accurately account for the fuzzy and non-Gaussian distributions of PET images. An automatic and reproducible estimation scheme of the norm on an image-by-image basis was developed. Robustness was assessed by studying the consistency of results obtained on multiple acquisitions of the NEMA phantom on three different scanners with varying acquisition parameters. Accuracy was evaluated using classification errors (CEs) on simulated and clinical images. SPEQTACLE was compared to another FCM implementation, fuzzy local information C-means (FLICM) and fuzzy locally adaptive Bayesian (FLAB). Results: SPEQTACLE demonstrated a level of robustness similar to FLAB (variability of 14% ± 9% vs 14% ± 7%, p = 0.15) and higher than FLICM (45% ± 18%, p < 0.0001), and improved accuracy with lower CE (14% ± 11%) over both FLICM (29% ± 29%) and FLAB (22% ± 20%) on simulated images. Improvement was significant for the more challenging cases with CE of 17% ± 11% for SPEQTACLE vs 28% ± 22% for FLAB (p = 0.009) and 40% ± 35% for FLICM (p < 0.0001). For the clinical cases, SPEQTACLE outperformed FLAB and FLICM (15% ± 6% vs 37% ± 14% and 30% ± 17%, p < 0.004). Conclusions: SPEQTACLE benefitted from the fully automatic estimation of the norm on a case-by-case basis. This promising approach will be extended to multimodal images and multiclass estimation in future developments.

  19. A novel {sup 18}F-labeled two-helix scaffold protein for PET imaging of HER2-positive tumor

    Miao, Zheng; Ren, Gang; Jiang, Lei; Liu, Hongguang; Cheng, Zhen [Stanford University, Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Stanford Cancer Center, Bio-X Program, Stanford, CA (United States); Webster, Jack M.; Zhang, Rong; Syud, Faisal [General Electric Company, Global Research, Niskayuna, NY (United States); Namavari, Mohammad; Gambhir, Sanjiv S. [Stanford University, MIPS, Departments of Radiology and Bioengineering, Stanford Cancer Center, Bio-X Program, Stanford, CA (United States)

    2011-11-15

    Two-helix scaffold proteins ({proportional_to} 5 kDa) against human epidermal growth factor receptor type 2 (HER2) have been discovered in our previous work. In this research we aimed to develop an {sup 18}F-labeled two-helix scaffold protein for positron emission tomography (PET) imaging of HER2-positive tumors. An aminooxy-functionalized two-helix peptide (AO-MUT-DS) with high HER2 binding affinity was synthesized through conventional solid phase peptide synthesis. The purified linear peptide was cyclized by I{sub 2} oxidation to form a disulfide bridge. The cyclic peptide was then conjugated with a radiofluorination synthon, 4-{sup 18}F-fluorobenzyl aldehyde ({sup 18}F-FBA), through the aminooxy functional group at the peptide N terminus (30% yield, non-decay corrected). The binding affinities of the peptides were analyzed by Biacore analysis. Cell uptake assay of the resulting PET probe, {sup 18}F-FBO-MUT-DS, was performed at 37 C. {sup 18}F-FBO-MUT-DS with high specific activity (20-32 MBq/nmol, 88-140 {mu}Ci/{mu}g, end of synthesis) was injected into mice xenograft model bearing SKOV3 tumor. MicroPET and biodistribution and metabolic stability studies were then conducted. Cell uptake assays showed high and specific cell uptake ({proportional_to}12% applied activity at 1 h) by incubation of {sup 18}F-FBO-MUT-DS with HER2 high-expressing SKOV3 ovarian cancer cells. The affinities (K{sub D}) of AO-MUT-DS and FBO-MUT-DS as tested by Biacore analysis were 2 and 1 nM, respectively. In vivo small animal PET demonstrated fast tumor targeting, high tumor accumulation, and good tumor to normal tissue contrast of {sup 18}F-FBO-MUT-DS. Biodistribution studies further revealed that the probe had excellent tumor uptake (6.9%ID/g at 1 h post-injection) and was cleared through both liver and kidneys. Co-injection of the probe with 500 {mu}g of HER2 Affibody protein reduced the tumor uptake (6.9 vs 1.8%ID/g, p < 0.05). F-FBO-MUT-DS displays excellent HER2 targeting ability

  20. [11C]Sorafenib: Radiosynthesis and preclinical evaluation in tumor-bearing mice of a new TKI-PET tracer

    Introduction: Tyrosine kinase inhibitors (TKIs) like sorafenib are important anticancer therapeutics with thus far limited treatment response rates in cancer patients. Positron emission tomography (PET) could provide the means for selection of patients who might benefit from TKI treatment, if suitable PET tracers would be available. The aim of this study was to radiolabel sorafenib (1) with carbon-11 and to evaluate its potential as TKI-PET tracer in vivo. Methods: Synthetic methods were developed in which sorafenib was labeled at two different positions, followed by a metabolite analysis in rats and a PET imaging study in tumor-bearing mice. Results: [methyl-11C]-1 and [urea-11C]-1 were synthesized in yields of 59% and 53%, respectively, with a purity of > 99%. The identity of the products was confirmed by coinjection on HPLC with reference sorafenib. In an in vivo metabolite analysis [11C]sorafenib proved to be stable. The percentage of intact product in blood–plasma after 45 min was 90% for [methyl-11C]-1 and 96% for [urea-11C]-1, respectively. Due to the more reliable synthesis, further research regarding PET imaging was performed with [methyl-11C]-1 in nude mice bearing FaDu (head and neck cancer), MDA-MB-231 (breast cancer) or RXF393 (renal cancer) xenografts. Highest tracer accumulation at a level of 2.52 ± 0.33 %ID/g was observed in RXF393, a xenograft line extensively expressing the sorafenib target antigen Raf-1 as assessed by immunohistochemistry. Conclusion: In conclusion, we have synthesized [11C]sorafenib as PET tracer, which is stable in vivo and has the capability to be used as PET tracer for imaging in tumor-bearing mice

  1. Correlation of F-18 FDG PET with morphometric tumor response after neoadjuvant chemoradiation in locally advanced (stage III) non-small cell lung cancer (NSCLC)

    Aim: To determine the role of 2-[(18)F] fluoro-2- deoxy-D-glucose (FDG) positron emission tomography (PET) in morphometric tumor response after neoadjuvant chemoradiation, findings in 32 patients were analyzed prospectively in an ongoing multicenter trial (LUCAS-MD, Germany). Material and Methods: Inclusion criteria was histologically confirmed NSCLC stage IIIA/IIIB. For staging all patients received a PET scan in addition to a spiral CT and/or MRI before therapy. Neoadjuvant treatment consisted of 2-3 cycles of chemotherapy with paclitaxel (225 mg/m2) and carboplatin (AUC 6), each d1 q22 and a block of chemoradiation (45Gy, 1.5Gy b.i.d., concomitant with paclitaxel (50 mg/m2) and carboplatin (AUC = 2), each d1, d8, d15) followed by surgery. All patients received a second PET after completion of neoadjuvant therapy prior to surgery. Whole-body PET (ECAT Exact 47) studies (attenuation corrected, iteratively reconstructed) were obtained 60 min. after injection of 6 MBq/kg body weight F-18 FDG. For semi-quantitative analysis, the tumor standardized uptake values (SUV), the tumor to background SUV ratio (T/B ratio), the metabolic tumor diameter (MTD) and the metabolic tumor index (MTI = SUV x MTD) were assessed in all primary tumors and in metastatic lymph nodes. Additionally, image fusion of PET with CT data was applied (using a HERMES Computer, Nuclear Diagnostics, Sweden). Results: So far, all patients (7/32) with complete metabolic response in lymph node metastases detected by PET, had no vital tumor cells (morphometric regression grade III). In primary tumors showing complete metabolic response, the regression grade was IIB (less than 10% vital tumor cells) or III. Conclusion: Morphometric tumor response after neoadjuvant therapy correlates strongly with metabolic remission by FDG-PET. PET precedes the tumor response as measured by CT after neoadjuvant treatment and may predict the long term therapeutic outcome in stage III NSCLC

  2. Synthesis and evaluation of two novel 2-nitroimidazole derivatives as potential PET radioligands for tumor imaging

    Zha Zhihao; Zhu Lin [Key Laboratory of Radiopharmaceuticals, Beijing Normal University, Ministry of Education, Beijing 100875 (China); Department of Radiology, University of Pennsylvania, Philadelphia, PA 19014 (United States); Liu Yajing; Du Fenghua; Gan Hongmei; Qiao Jinping [Key Laboratory of Radiopharmaceuticals, Beijing Normal University, Ministry of Education, Beijing 100875 (China); Kung, Hank F., E-mail: kunghf@gmail.co [Key Laboratory of Radiopharmaceuticals, Beijing Normal University, Ministry of Education, Beijing 100875 (China); Department of Radiology, University of Pennsylvania, Philadelphia, PA 19014 (United States)

    2011-05-15

    }F]7) and NEFT ([{sup 19}F]8). Conclusions: In this research, two new fluorine-18 labeled 2-nitroimidazole derivatives, [{sup 18}F]7 and [{sup 18}F]8, both of which containing in vivo hydrolyzable group, were successfully prepared. Further biological evaluations are warranted to investigate their potential as PET radioligands for imaging tumor.

  3. Synthesis and evaluation of two novel 2-nitroimidazole derivatives as potential PET radioligands for tumor imaging

    derivatives, [18F]7 and [18F]8, both of which containing in vivo hydrolyzable group, were successfully prepared. Further biological evaluations are warranted to investigate their potential as PET radioligands for imaging tumor.

  4. Molecular markers derived from bombesin for tumor diagnosis by SPECT and PET; Marcadores moleculares derivados da bombesina para diagnostico de tumores por SPECT e PET

    Pujatti, Priscilla Brunelli

    2012-07-01

    A high number of molecules have already been identified to have high affinity to some receptors overexpressed on tumour cells and the radiolabelling of those molecules offers the possibility of new compounds for tumour diagnosis and therapy by nuclear medicine. Among of those molecules, bombesin (BBN) has become focus of interest, as its BB{sub 2} receptors are known to be overexpressed in prostate, breast, colon, pancreatic and lung tumour, as long as glioblastomas and neuroblastomas. BBN agonists and antagonists have already been described for this purpose and promising results were obtained in preclinical studies. However, most of them exhibited high abdominal accumulation, especially in pancreas and intestines, which can compromise diagnosis accuracy and cause serious adverse effects in therapy. In this context, the goal of the present work to radiolabel new BBN derivatives with {sup 11}1In and {sup 68}Ga and to evaluate their potential for BB{sub 2} positive tumors diagnosis by single photon emission tomography (SPECT) and positron emission tomography (PET). The structure of studied peptides was Q-YG{sub n}-BBN(6-14), where Q is the chelator, n is the number of glycine aminoacids in the spacer YG{sub n} and BBN(6-14) is the original bombesin sequence from the aminoacid 6 to 14. The derivative in which the last aminoacid (methionine, Met) was replaced by norleucine (Nle) was also evaluated. The experimental evaluation of the bombesin derivatives was divided into four steps: computational studies, molecular markers for SPECT, molecular markers for PET and toxicological studies. The theoretical partition (log P) and distribution (log D) coefficients were calculated for all bombesin derivatives conjugated to DTPA (diethylenetriaminepentaacetic acid) and DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) chelators applying computational programmes. Bombesin derivatives for SPECT were developed by radiolabelling DTPA-conjugated bombesin derivatives with

  5. Does the pretreatment tumor sampling location correspond with metabolic activity on 18F-FDG PET/CT in breast cancer patients scheduled for neoadjuvant chemotherapy?

    Koolen, Bas B., E-mail: b.koolen@nki.nl [Department of Nuclear Medicine, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Department of Surgical Oncology, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Elshof, Lotte E. [Department of Nuclear Medicine, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Department of Surgical Oncology, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Loo, Claudette E. [Department of Radiology, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Wesseling, Jelle [Department of Pathology, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Vrancken Peeters, Marie-Jeanne T.F.D. [Department of Surgical Oncology, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Vogel, Wouter V. [Department of Nuclear Medicine, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Rutgers, Emiel J.Th. [Department of Surgical Oncology, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Valdés Olmos, Renato A. [Department of Nuclear Medicine, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands)

    2013-12-01

    Purpose: To define the correlation between the core biopsy location and the area with highest metabolic activity on 18F-FDG PET/CT in stage II–III breast cancer patients before neoadjuvant chemotherapy. Also, we would like to select a subgroup of patients in which PET/CT information may optimize tumor sampling. Methods: A PET/CT in prone position was acquired in 199 patients with 203 tumors. The distance and relative difference in standardized uptake value (SUV) between core biopsy localization (indicated by a marker) and area with highest degree of FDG uptake were evaluated. A distance ≥2 cm and a relative difference in SUV ≥25% were considered clinically relevant and a combination of both was defined as non-correspondence. Non-correspondence for different tumor characteristics (TNM stage, lesion morphology on MRI and PET/CT, histology, subtype, grade, and Ki-67) was assessed. Results: Non-correspondence was found in 28 (14%) of 203 tumors. Non-correspondence was significantly associated with T-stage, lesion morphology on MRI and PET/CT, tumor diameter, and histologic type. It was more often seen in tumors with a higher T-stage (p = 0.028), diffuse (non-mass) and multifocal tumors on MRI (p = 0.001), diffuse and multifocal tumors on PET/CT (p < 0.001), tumors >3 cm (p < 0.001), and lobular carcinomas (p < 0.001). No association was found with other features. Conclusion: Non-correspondence between the core biopsy location and area with highest FDG uptake is regularly seen in stage II–III breast cancer patients. PET/CT information and possibly FDG-guided biopsies are most likely to improve pretreatment tumor sampling in tumors >3 cm, lobular carcinomas, and diffuse and multifocal tumors.

  6. Does the pretreatment tumor sampling location correspond with metabolic activity on 18F-FDG PET/CT in breast cancer patients scheduled for neoadjuvant chemotherapy?

    Purpose: To define the correlation between the core biopsy location and the area with highest metabolic activity on 18F-FDG PET/CT in stage II–III breast cancer patients before neoadjuvant chemotherapy. Also, we would like to select a subgroup of patients in which PET/CT information may optimize tumor sampling. Methods: A PET/CT in prone position was acquired in 199 patients with 203 tumors. The distance and relative difference in standardized uptake value (SUV) between core biopsy localization (indicated by a marker) and area with highest degree of FDG uptake were evaluated. A distance ≥2 cm and a relative difference in SUV ≥25% were considered clinically relevant and a combination of both was defined as non-correspondence. Non-correspondence for different tumor characteristics (TNM stage, lesion morphology on MRI and PET/CT, histology, subtype, grade, and Ki-67) was assessed. Results: Non-correspondence was found in 28 (14%) of 203 tumors. Non-correspondence was significantly associated with T-stage, lesion morphology on MRI and PET/CT, tumor diameter, and histologic type. It was more often seen in tumors with a higher T-stage (p = 0.028), diffuse (non-mass) and multifocal tumors on MRI (p = 0.001), diffuse and multifocal tumors on PET/CT (p < 0.001), tumors >3 cm (p < 0.001), and lobular carcinomas (p < 0.001). No association was found with other features. Conclusion: Non-correspondence between the core biopsy location and area with highest FDG uptake is regularly seen in stage II–III breast cancer patients. PET/CT information and possibly FDG-guided biopsies are most likely to improve pretreatment tumor sampling in tumors >3 cm, lobular carcinomas, and diffuse and multifocal tumors

  7. The clinical application of 4D 18F-FDG PET/CT on gross tumor volume delineation for radiotherapy planning in esophageal squamous cell cancer

    Wang, Yao-Ching; Hsieh, Te-Chun; Yu, Chun-Yen; Yen, Kuo-Yang; Chen, Shang-Wen; Yang, Shih-Neng; Chien, Chun-Ru; Hsu, Shih-Ming; Pan, Tinsu; Kao, Chia-Hung; Liang, Ji-An

    2012-01-01

    A combination of four-dimensional computed tomography with 18F-fluorodeoxyglucose positron emission tomography (4D CT-FDG PET) was used to delineate gross tumor volume (GTV) in esophageal cancer (EC). Eighteen patients with EC were prospectively enrolled. Using 4D images taken during the respiratory cycle, the average CT image phase was fused with the average FDG PET phase in order to analyze the optimal standardized uptake values (SUV) or threshold. PET-based GTV (GTVPET) was determined with...

  8. The correlation between PET-CT imaging and microvessed density in rabbit lung VX2 tumor model

    Objective: To evaluate and compare the suitability of 11C-choline and 18F-FDG PET-CT for reflecting tumors angiogenesis. Methods: Fifty-four New Zealand white rabbits which weighted 2.5∼3.0 kg were used in the experiment. Under general anesthesia, a needle was transthoracically inserted into the right lung, 0.5 ml viable VX2 tumor cell suspension was slowly injected through the needle to establish the model. 11C-choline and 18F-FDG PET-CT were performed after 10∼11 d. The tumors SUVmax were calculated. The sections were stained with hematoxylin and eosin, and immunostained for CD34. Assessment of micro vessel density (MVD) was performed by computer-assisted image analysis. The relationship 11C-choline SUVmax and 18F-FDG SUVmax with tumor size and MVD were statistically analyzed. Results: Thirty-three rabbits successfully completed all imaging examinations. 11C-choline and 18F-FDG differently accumulated in all lung VX2 tumors. The mean of 11C-choline SUVmax was 4.02±3.07 (1.4∼12.2), and the mean of 18F-FDG SUVmax was 5.70±3.45 (1.0∼13.0). The mean size of tumor was (1.68±1.61)cm3 (0.13∼8.00 cm3). Under high power microscope field of vision (200 x 0.739 mm2), the mean of MVD was 35.8±13.6 (13∼64), 11C-choline SUVmax did not correlate with tumor size and MVD. 18F-FDG SUVmax significantly and positively related to MVD (r=0.525, P=0.002). There was a critical positive correlation between 18F-FDG SUVmax and tumor size (r=0.335, P=0.057). Conclusion: In the rabbit VX2 lung tumor model, 18F-FDG SUVmax correlated with MVD, so 18F-FDG PET-CT could reflect tumor angiogenesis. 11C-choline SUVmax did not statistically correlate with MVD, and 11C-choline PET-CT could not reflect tumor angiogenesis. (authors)

  9. SU-E-I-81: Targeting of HER2-Expressing Tumors with Dual PET-MR Imaging Probes

    Xu, P; Peng, Y; Sun, M; Yang, X [Suzhou Institute of Biomedical Engineering and Technology Chinese Academy o, Suzhou, Jiangsu (China)

    2015-06-15

    Purpose: The detection of human epidermal growth factor receptor type 2 (HER2) expression in malignant tumors provides important information influencing patient management. Radionuclide in vivo imaging of HER2 may permit the detection of HER2 in both primary tumors and metastases by a single noninvasive procedure. Trastuzumab, effective in about 15 % of women with breast cancer, downregulates signalling through the Akt/PI3K and MAPK pathways.These pathways modulate metabolism which can be monitored by positron emission tomography (PET) and magnetic resonance imaging (MRI). Methods: The relationship between response of HER2 overexpressing tumours and changes in imaging PET or SPECT and MRI will be examined by a integrated bimodal imaging probe.Small (7 kDa) high-affinity anti-HER2 Affibody molecules and KCCYSL targeting peptide may be suitable tracers for visualization of HER2-expressing tumors. Peptide-conjugated iron oxide nanoparticles (Fe3O4 NPs) as MRI imaging and CB-TE2A as PET imaging are integrated into a single synthetic molecule in the HER2 positive cancer. Results: One of targeted contrast bimodal imaging probe agents was synthesized and evaluated to target HER2-expressing tumors in a HER2 positive rat model. We will report the newest results regarding the development of bimodal imaging probes. Conclusion: The preliminary results of the bimodal imaging probe presents high correlation of MRI signal and PET imaging intensity in vivo. This unique feature can hardly be obtained by single model contrast agents. It is envisioned that this bimodal agents can hold great potential for accurate detection of HER2-expressing tumors which are critical for clinical management of the disease.

  10. SU-E-I-81: Targeting of HER2-Expressing Tumors with Dual PET-MR Imaging Probes

    Purpose: The detection of human epidermal growth factor receptor type 2 (HER2) expression in malignant tumors provides important information influencing patient management. Radionuclide in vivo imaging of HER2 may permit the detection of HER2 in both primary tumors and metastases by a single noninvasive procedure. Trastuzumab, effective in about 15 % of women with breast cancer, downregulates signalling through the Akt/PI3K and MAPK pathways.These pathways modulate metabolism which can be monitored by positron emission tomography (PET) and magnetic resonance imaging (MRI). Methods: The relationship between response of HER2 overexpressing tumours and changes in imaging PET or SPECT and MRI will be examined by a integrated bimodal imaging probe.Small (7 kDa) high-affinity anti-HER2 Affibody molecules and KCCYSL targeting peptide may be suitable tracers for visualization of HER2-expressing tumors. Peptide-conjugated iron oxide nanoparticles (Fe3O4 NPs) as MRI imaging and CB-TE2A as PET imaging are integrated into a single synthetic molecule in the HER2 positive cancer. Results: One of targeted contrast bimodal imaging probe agents was synthesized and evaluated to target HER2-expressing tumors in a HER2 positive rat model. We will report the newest results regarding the development of bimodal imaging probes. Conclusion: The preliminary results of the bimodal imaging probe presents high correlation of MRI signal and PET imaging intensity in vivo. This unique feature can hardly be obtained by single model contrast agents. It is envisioned that this bimodal agents can hold great potential for accurate detection of HER2-expressing tumors which are critical for clinical management of the disease

  11. The Feasibility of 18F Fluorothymidine PET for Prediction of Tumor Response after Induction Chemotherapy Followed by Chemoradiotherapy with S 1/Oxaliplatin in Patients with Resectable Esophageal Cancer

    The aim of this study was to determine whether 18F fluorothymidine (FLT) PET is feasible for the early prediction of tumor response to induction chemotherapy followed by concurrent chemoradiotherapy in patients with esophageal cancer. This study was prospectively performed as a collateral study of randomized phase II study of preoperative concurrent chemoradiotherapy with S 1/oxaliplatin in patients with resectable esophageal cancer. 18F FLT positron emission tomography (PET) images were obtained before and after two cycles of induction chemotherapy, and the percent change of maximum standardized uptake value (SUVmax) was calculated. All patients underwent esophagography, gastrofiberoscopy, endoscopic ultrasonography (EUS), computed tomography (CT) and 18F fluorodeoxyglucose (FDG) PET at baseline and 3-4 weeks after completion of concurrent chemoradiotherapy. Final tumor response was determined by both clinical and pathologic tumor responses after surgery. The 13 patients for induction chemotherapy group were enrolled until interim analysis. In a primary tumor visual analysis, the tumor detection rates of baseline 18F FLT and 18F FDG PET were 85% and 100%, respectively. The tumor uptakes on 18F FLT PET were lower than those of 18F FDG PET. Among nine patients who completed second 18F FLT PET, eight patients were responders and one patient was a non responder in the assessment of final tumor response. The percent change of SUVmax in responders ranged from 41.2% to 79.2% (median 57.1%), whereas it was 10.2% in one non responder. The percent change of tumor uptake in 18F FLT PET after induction chemotherapy might be feasible for early prediction of tumor response after induction chemotherapy and concurrent chemoradiotherapy in patients with esophageal cancer

  12. Metabolic characterisation by PET-T.D.M. with 18 F.D.G. of non secreting adrenal tumors and undetermined by conventional imaging

    The PET-T.D.M. with F.D.G. allows a precise characterization of adrenal tumors with an excellent sensitivity and predictive negative value among these patients. So, a negative examination can be a strong argument for a benign tumor, that could potentially avoid surgery for the adrenal tumors with non conclusive examinations of conventional imaging. (N.C.)

  13. Malignant phyllodes tumor of the breast metastasizing to the vulva: {sup 18}F FDG PET CT Demonstrating rare metastasis from a rare tumor

    Khangembam, Bang Kim Chand Ra; Sharma, Punit; Singla, Su Has; Singhal, Abinav; Dhull, Varun Singh; Bal, Chand Rasek Har; Kumar, Rakesh [All India Institute of Medical Sciences, New Delhi (India)

    2012-09-15

    Phyllodes tumors are extremely rare fibroepithelial neoplasms accounting for 0.3 to 0.5% of all female breast tumors with an incidence of 2.1 per 1 million women. They are classified histologically into benign, borderline and malignant varieties. The majority of them are benign, with only 25% being malignant. Surgery remains the mainstay of treatment. One characteristic is that although the malignant variety tends to metastasize and recur, the benign form has also been found to behave in a similar manner. Benign phyllodes tumor has a 21% risk of local recurrence, while that of the malignant variety ranges from 20 to 32%. In patients with malignant phyllodes tumor, the rate of distant metastases ranges from 25 to 40%. The most frequent sites of distant metastasis is uncommon as this tumor spreads by hematogeneous route. Other sites for distant metastasis have been reported sporadically, including the duodenum, pancreas, brain, nasal cavity, forearm, parotid, skin, oral cavity, skeletal muscle, mandible and maxilla. We present a rare case of recurrent malignant phyllodes tumor with metastasis to the vulva, which has not been reported in the literature to the best of our knowledge. A 49 year old female who had undergone lumpectomy and locoregional radiotherapy 1 year previously for malignant phyllodes tumor of the right breast presented with difficulty in breathing and cervical lymphadenopathy. Chest X ray showed multiple pulmonary nodules suggestive of metastasis. She was referred for restaging with 18F fluorodeoxyglucose (FDG)positron emission tomography computed tomography (PET CT)FDG PET CT. Maximum intensity projection (MIP)PET images revealed multiple FDG avid enlarged cervical lymph nodes, bilateral pulmonary nodules along with left pleural effusion and extensive bone marrow metastases. The interesting finding was an intensely FDG avid (SUV{sup max}-21.4)subcutaneous soft tissue density lesion (measuring 2.0x2.2x2.0cm)in the vulva, which was later proved to be

  14. Malignant phyllodes tumor of the breast metastasizing to the vulva: 18F FDG PET CT Demonstrating rare metastasis from a rare tumor

    Phyllodes tumors are extremely rare fibroepithelial neoplasms accounting for 0.3 to 0.5% of all female breast tumors with an incidence of 2.1 per 1 million women. They are classified histologically into benign, borderline and malignant varieties. The majority of them are benign, with only 25% being malignant. Surgery remains the mainstay of treatment. One characteristic is that although the malignant variety tends to metastasize and recur, the benign form has also been found to behave in a similar manner. Benign phyllodes tumor has a 21% risk of local recurrence, while that of the malignant variety ranges from 20 to 32%. In patients with malignant phyllodes tumor, the rate of distant metastases ranges from 25 to 40%. The most frequent sites of distant metastasis is uncommon as this tumor spreads by hematogeneous route. Other sites for distant metastasis have been reported sporadically, including the duodenum, pancreas, brain, nasal cavity, forearm, parotid, skin, oral cavity, skeletal muscle, mandible and maxilla. We present a rare case of recurrent malignant phyllodes tumor with metastasis to the vulva, which has not been reported in the literature to the best of our knowledge. A 49 year old female who had undergone lumpectomy and locoregional radiotherapy 1 year previously for malignant phyllodes tumor of the right breast presented with difficulty in breathing and cervical lymphadenopathy. Chest X ray showed multiple pulmonary nodules suggestive of metastasis. She was referred for restaging with 18F fluorodeoxyglucose (FDG)positron emission tomography computed tomography (PET CT)FDG PET CT. Maximum intensity projection (MIP)PET images revealed multiple FDG avid enlarged cervical lymph nodes, bilateral pulmonary nodules along with left pleural effusion and extensive bone marrow metastases. The interesting finding was an intensely FDG avid (SUVmax-21.4)subcutaneous soft tissue density lesion (measuring 2.0x2.2x2.0cm)in the vulva, which was later proved to be

  15. Imaging of lung metastasis tumor mouse model using [{sup 18}F]FDG small animal PET and CT

    Kim, June Youp; Woo, Sang Keun; Lee, Tae Sup [Korea Institute of Radiological and Medical Sciences (KIRAMS), Seoul (Korea, Republic of)] (and others)

    2007-02-15

    The purpose of this study is to image metastaic lung melanoma model with optimal pre-conditions for animal handling by using [{sup 18}F]FDG small animal PET and clinical CT. The pre-conditions for lung region tumor imaging were 16-22 h fasting and warming temperature at 30 .deg. C. Small animal PET image was obtained at 60 min postinjection of 7.4 MBq [{sup 18}F]FDG and compared pattern of [{sup 18}F]FDG uptake and glucose standard uptake value (SUVG) of lung region between Ketamine/Xylazine (Ke/Xy) and Isoflurane (Iso) anesthetized group in normal mice. Metastasis tumor mouse model to lung was established by intravenous injection of B16-F10 cells in C57BL/6 mice. In lung metastasis tumor model, [{sup 18}F]FDG image was obtained and fused with anatomical clinical CT image. Average blood glucose concentration in normal mice were 128.0 {+-} 22.87 and 86.0 {+-} 21.65 mg/dL in Ke/Xy group and Iso group, respectively. Ke/Xy group showed 1.5 fold higher blood glucose concentration than Iso group. Lung to Background ratio (L/B) in SUVG image was 8.6 {+-} 0.48 and 12.1 {+-}0.63 in Ke/Xy group and Iso group, respectively. In tumor detection in lung region, [{sup 18}F]FDG image of Iso group was better than that of Ke/Xy group, because of high L/B ratio. Metastatic tumor location in [{sup 18}F]FDG small animal PET image was confirmed by fusion image using clinical CT. Tumor imaging in small animal lung region with [{sup 18}F]FDG small animal PET should be considered pre-conditions which fasting, warming and an anesthesia during [{sup 18}F]FDG uptake. Fused imaging with small animal PET and CT image could be useful for the detection of metastatic tumor in lung region.

  16. A novel 18F-labeled two-helix scaffold protein for PET imaging of HER2-positive tumor

    Two-helix scaffold proteins (∝ 5 kDa) against human epidermal growth factor receptor type 2 (HER2) have been discovered in our previous work. In this research we aimed to develop an 18F-labeled two-helix scaffold protein for positron emission tomography (PET) imaging of HER2-positive tumors. An aminooxy-functionalized two-helix peptide (AO-MUT-DS) with high HER2 binding affinity was synthesized through conventional solid phase peptide synthesis. The purified linear peptide was cyclized by I2 oxidation to form a disulfide bridge. The cyclic peptide was then conjugated with a radiofluorination synthon, 4-18F-fluorobenzyl aldehyde (18F-FBA), through the aminooxy functional group at the peptide N terminus (30% yield, non-decay corrected). The binding affinities of the peptides were analyzed by Biacore analysis. Cell uptake assay of the resulting PET probe, 18F-FBO-MUT-DS, was performed at 37 C. 18F-FBO-MUT-DS with high specific activity (20-32 MBq/nmol, 88-140 μCi/μg, end of synthesis) was injected into mice xenograft model bearing SKOV3 tumor. MicroPET and biodistribution and metabolic stability studies were then conducted. Cell uptake assays showed high and specific cell uptake (∝12% applied activity at 1 h) by incubation of 18F-FBO-MUT-DS with HER2 high-expressing SKOV3 ovarian cancer cells. The affinities (KD) of AO-MUT-DS and FBO-MUT-DS as tested by Biacore analysis were 2 and 1 nM, respectively. In vivo small animal PET demonstrated fast tumor targeting, high tumor accumulation, and good tumor to normal tissue contrast of 18F-FBO-MUT-DS. Biodistribution studies further revealed that the probe had excellent tumor uptake (6.9%ID/g at 1 h post-injection) and was cleared through both liver and kidneys. Co-injection of the probe with 500 μg of HER2 Affibody protein reduced the tumor uptake (6.9 vs 1.8%ID/g, p 18F-based PET probes. (orig.)

  17. Improved automated production of 18F-FMISO and its tumor hypoxia imaging by Micro-PET/CT

    Background: 1-H-1-(3-[18F]fluoro-2-hydroxypropyl)-2-nitroimidazole (18F-FMISO) is a specific molecular imaging probe for tumor hypoxia imaging, and its PET/CT imaging has an important clinical value for planning cancer radiotherapy target volume. Purpose: This study aimed to develop an improved, automated production of 18F-FMISO and to perform Micro-PET/CT imaging of tumor hypoxia. Methods: Based on the labeling precursor NITTP and a simple 'one-pot' method, an upgraded Explora GN module together with Explora LC was adopted to run radiofluorination (NITTP (10 mg), MeCN (1.0 mL), 120℃, 5.0 min), hydrolysis (HCI (1.0 mol/L, 1.0 mL), 130℃, 8.0 min) and high performance liquid chromatography (HPLC) purification to produce 18F-FMISO automatically. Moreover, Radio-HPLC and Radio-TLC were applied for the quality control, and Micro-PET/CT scanner for hypoxia imaging of SW1990 pancreatic tumor-bearing mice. Results: As results, 18F-FMISO was obtained with the synthesis time for about 65 min, the radiochemical yield of (30±5.0)% (no decay corrected, n=20), the radiochemical purity of above 99%, the specific activity of (2.04±0.17)x1011 Bq·μmol-1, plus with the enhanced chemical purity. Moreover, MicroPET/CT imaging showed that 18F-FMISO presented whole-body distribution in SW1990 tumor-bearing mice, and the optimized time point for tumor hypoxia imaging was 3 h post injection with the uptake ratios of tumor-to-muscle of 3.00±0.08. Conclusion: In sum, we developed an improved, automated production of 18F-FMISO with high performance liquid chromatography purification, high radiochemical yield, high specific activity and high reliability , and also verified its MicroPET/CT imaging of tumor hypoxia for providing experimental reference data. (authors)

  18. Quantification of immunohistochemical expression of somatostatin receptors in neuroendocrine tumors using 68Ga-DOTATATE PET/CT

    The immunohistochemical expression of somatostatin receptor (SSTR) subtype 2 was compared to quantitative 68Ga-DOTATATE PET in neuroendocrine tumors (NET). In 27 patients suffering from metastatic NET the expression of somatostatin receptors (SSTR, score 0-3) and the Ki-67 index were assessed. The immunohistochemical findings were compared with the 68Ga-DOTATATE PET uptake in these tumors using the SUVmax (standardized uptake value). Both values were compared with the Ki-67 proliferation index. The SUVmax in NET without SSTR expression was significantly lower compared to those with SSTR expression (p 68Ga-DOTATATE. The SUVmax correlated significantly (r=0.40, p max (r=-0.33, p=0.11). 68Ga-DOTATATE uptake was moderately correlated with the results of immunohistochemical SSTR analyses. However, SSTR negative NET may show high uptake of 68Ga-DOTATATE. (orig.)

  19. Clinical Usefulness of 18F-FDG PET/CT in the Detection of Early Recurrence in Treated Cervical Cancer Patients with Unexplained Elevation of Serum Tumor Markers

    Chong, Ari; Ha, Jung-Min; Jeong, Shin Young; Song, Ho-Chun; Min, Jung Joon; Bom, Hee-Seung; Choi, Ho-Sun

    2013-01-01

    We investigated the diagnostic value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) for restaging of treated uterine cervix squamous cell cancer with tumor maker elevation that was not explained by other conventional evaluation. We enrolled 32 cases who underwent PET/CT for the restaging of treated cervical cancer with tumor marker elevation that was not explained by recent conventional evaluation. All enrolled cases had squamous cell carcinoma. Increased ...

  20. Clinical relevance of F-18 FDG PET for imaging of neuroendocrine tumors; Wertigkeit der F-18-FDG-PET bei neuroendokrinen Tumoren

    Adams, S. [Klinikum der Ruhr-Univ. Bochum - Marienhospital, Herne (Germany). Klinik fuer Radiologie und Nuklearmedizin; Baum, R.P. [Zentralklinik Bad Berka (Germany). Klinik fuer Nuklearmedizin/PET-Zentrum; Hoer, G. [Frankfurt Univ., Frankfurt am Main (Germany). Klinik fuer Nuklearmedizin

    2001-04-01

    Neuroendocrine tumors are characterized immunocytochemically by the expression of different peptides and biogenic amines. Hormones induce their biological action by binding to and stimulating specific membrane-associated receptors for e.g. somatostatin. The presence of somatostatin receptors (SR) has been described mainly in endocrine glands and the central nervous system. Interestingly, a large variety of human tumors, including gastroenteropancreatic (GEP) tumors and medullary thyroid carcinomas (MTC) also express a high density of SR and can be imaged with [{sup 111}In-DTPA-D-Phe{sup 1}]-pentetreotide. Cell proliferative activity is an important indicator of the growth of various malignant tumors associated with a poorer prognosis and Ki-67 expression. {sup 18}F-FDG is a marker of tumor viability, based upon the increased glycolysis that is associated with malignancy as compared with normal tissue. SR-containing neuroendocrine tumors are well-differentiated and tend to grow slowly. Furthermore, these tumors demonstrate inverse relationship between in vivo SR expression, cell proliferation (low Ki-67 expression) and FDG uptake (normal biodistribution). In comparison, less differentiated tumors, e.g. atypical carcinoids or MTC with increasing CEA levels show mitotic activity (high levels of Ki-67 immunoreactivity and increased FDG uptake) and often lack of SR. In conclusion, SR scintigraphy has been shown to localize well-differentiated neuroendocrine tumors. In contrast, PET imaging is valuable for predicting malignancy only in less differentiated tumors with incresed glucose metabolism. Therefore, an additional F-18 FDG PET should be performed if SR scintigraphy (GEP tumors) or combined imaging using [{sup 111}In-DTPA-D-Phe{sup 1}]-pentetreotide and {sup 99m}Tc(V)-DMSA (MTC) is negative. (orig.) [German] Neuroendokrine Tumoren werden durch die spezifische Produktion von Polypeptidhormonen und biogenen Aminen klassifiziert. Die Informationsuebertragung der

  1. Analysis of pairwise correlations in multi-parametric PET/MR data for biological tumor characterization and treatment individualization strategies

    Leibfarth, Sara; Moennich, David; Thorwarth, Daniela [University Hospital Tuebingen, Section for Biomedical Physics, Department of Radiation Oncology, Tuebingen (Germany); Simoncic, Urban [University Hospital Tuebingen, Section for Biomedical Physics, Department of Radiation Oncology, Tuebingen (Germany); University of Ljubljana, Faculty of Mathematics and Physics, Ljubljana (Slovenia); Jozef Stefan Institute, Ljubljana (Slovenia); Welz, Stefan; Zips, Daniel [University Hospital Tuebingen, Department of Radiation Oncology, Tuebingen (Germany); Schmidt, Holger; Schwenzer, Nina [University Hospital Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany)

    2016-07-15

    The aim of this pilot study was to explore simultaneous functional PET/MR for biological characterization of tumors and potential future treatment adaptations. To investigate the extent of complementarity between different PET/MR-based functional datasets, a pairwise correlation analysis was performed. Functional datasets of N=15 head and neck (HN) cancer patients were evaluated. For patients of group A (N=7), combined PET/MR datasets including FDG-PET and ADC maps were available. Patients of group B (N=8) had FMISO-PET, DCE-MRI and ADC maps from combined PET/MRI, an additional dynamic FMISO-PET/CT acquired directly after FMISO tracer injection as well as an FDG-PET/CT acquired a few days earlier. From DCE-MR, parameter maps K{sup trans}, v{sub e} and v{sub p} were obtained with the extended Tofts model. Moreover, parameter maps of mean DCE enhancement, ΔS{sub DCE}, and mean FMISO signal 0-4 min p.i., anti A{sub FMISO}, were derived. Pairwise correlations were quantified using the Spearman correlation coefficient (r) on both a voxel and a regional level within the gross tumor volume. Between some pairs of functional imaging modalities moderate correlations were observed with respect to the median over all patient datasets, whereas distinct correlations were only present on an individual basis. Highest inter-modality median correlations on the voxel level were obtained for FDG/FMISO (r = 0.56), FDG/ anti A{sub FMISO} (r = 0.55), anti A{sub FMISO}/ΔS{sub DCE} (r = 0.46), and FDG/ADC (r = -0.39). Correlations on the regional level showed comparable results. The results of this study suggest that the examined functional datasets provide complementary information. However, only pairwise correlations were examined, and correlations could still exist between combinations of three or more datasets. These results might contribute to the future design of individually adapted treatment approaches based on multiparametric functional imaging.

  2. Assessment of the Tumor Redox Status in Head and Neck Cancer by 62Cu-ATSM PET

    Tsujikawa, Tetsuya; Asahi, Satoko; Oh, Myungmi; Sato, Yoshitaka; Narita, Norihiko; Makino, Akira; Mori, Tetsuya; Kiyono, Yasushi; Tsuchida, Tatsuro; Kimura, Hirohiko; Fujieda, Shigeharu; Okazawa, Hidehiko

    2016-01-01

    Purpose Tumor redox is an important factor for cancer progression, resistance to treatments, and a poor prognosis. The aim of the present study was to define tumor redox (over-reduction) using 62Cu-diacetyl-bis(N4-methylthiosemicarbazone) (62Cu-ATSM) PET and compare its prognostic potential in head and neck cancer (HNC) with that of 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG). Methods Thirty HNC patients (stage II–IV) underwent pretreatment 62Cu-ATSM and 18F-FDG PET scans. Maximum standardized uptake values (SUVATSM and SUVFDG) and tumor-to-muscle activity concentration ratios (TMRATSM and TMRFDG) were measured. Reductive-tumor-volume (RTV) was then determined at four thresholds (40%, 50%, 60%, and 70% SUVATSM), and total-lesion-reduction (TLR) was calculated as the product of the mean SUV and RTV for 62Cu-ATSM. In 18F-FDG, metabolic-tumor-volume (MTV) and total-lesion-glycolysis (TLG) were obtained at a threshold of 40%. A ROC analysis was performed to determine % thresholds for RTV and TLR showing the best predictive performance, and these were then used to determine the optimal cut-off values to stratify patients for each parameter. Progression-free-survival (PFS) and cause-specific-survival (CSS) were evaluated by the Kaplan-Meier method. Results The means ± standard deviations of PFS and CSS periods were 16.4±13.4 and 19.2±12.4 months, respectively. A ROC analysis determined that the 70% SUVATSM threshold for RTV and TLR was the best for predicting disease progression and cancer death. Optimal cut-offs for each index were SUVATSM = 3.6, SUVFDG = 7.9, TMRATSM = 3.2, TMRFDG = 5.6, RTV = 2.9, MTV = 8.1, TLR = 14.0, and TLG = 36.5. When the cut-offs for TMRATSM and TLR were set as described above in 62Cu-ATSM PET, patients with higher TMRATSM (p = 0.03) and greater TLR (p = 0.02) showed significantly worse PFS, while patients with greater TLR had significantly worse CSS (p = 0.02). Only MTV in 18F-FDG PET predicted differences in PSF and CSS (p = 0.03 and p = 0

  3. Evolving role of 18F-FDG-PET/CT for the body tumor and metastases in pediatrics

    18F-FDG-positron emission tomography-computerized tomography (18F-FDG-PET/CT) scan is an important imaging tool which may provide both functional and anatomical information in a single diagnostic test. It has the potential to be a valuable tool in the noninvasive evaluation and monitoring of pediatric tumors including the metastases because 18fluorodeoxyglucose (18F-FDG) is a glucose analogue that concentrates in areas of active metabolic activity. This review provides an update on functional and metabolic imaging approaches for assessment and management of the body tumor and metastases in pediatrics using a combined whole body 18F-FDG-PET/CT scanners. We discuss the benefits include improved pediatric patients' outcome facilitated by staging and monitoring of disease and better treatment planning. It is worth to concern the preparation of children undergoing PET studies and radiation dosimetry and its implications for family and caregivers. It is important to consider the normal distribution of 18FDG in children, common variations of the normal distribution. We show some of our cases that most tumors in children accumulate and retain FDG, allowing high-quality images of their distribution and pathophysiology either at the primary site as well as in the areas of metastatic disease.

  4. Evolving role of {sup 18}F-FDG-PET/CT for the body tumor and metastases in pediatrics

    Chen Zhengguang, E-mail: guangchen1@gmail.co [Department of Radiology, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, No. 5 Hai Yun Cang Beijing 100700 (China); Li Xiaozhen, E-mail: lixiaozhen79@gmail.co [Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No. 1 Shui Fu Yuan, Wang Fu Jing Da Jie, Beijing 100730 (China); Li Fang, E-mail: lifang@gmail.co [Department of Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No. 1 Shui Fu Yuan, Wang Fu Jing Da Jie, Beijing 100730 (China); Ouyang Qiaohong [Department of Nuclear Medicine, First Affiliated Hospital, PLA General Hospital, Beijing 100853 (China); Yu Tong [Imaging Center, Beijing Children' s Hospital Affiliated to Capital Medical University. 56, Nanlishi Road, Xicheng District, Beijing 100045 (China)

    2010-09-15

    {sup 18}F-FDG-positron emission tomography-computerized tomography ({sup 18}F-FDG-PET/CT) scan is an important imaging tool which may provide both functional and anatomical information in a single diagnostic test. It has the potential to be a valuable tool in the noninvasive evaluation and monitoring of pediatric tumors including the metastases because {sup 18}fluorodeoxyglucose ({sup 18}F-FDG) is a glucose analogue that concentrates in areas of active metabolic activity. This review provides an update on functional and metabolic imaging approaches for assessment and management of the body tumor and metastases in pediatrics using a combined whole body {sup 18}F-FDG-PET/CT scanners. We discuss the benefits include improved pediatric patients' outcome facilitated by staging and monitoring of disease and better treatment planning. It is worth to concern the preparation of children undergoing PET studies and radiation dosimetry and its implications for family and caregivers. It is important to consider the normal distribution of {sup 18}FDG in children, common variations of the normal distribution. We show some of our cases that most tumors in children accumulate and retain FDG, allowing high-quality images of their distribution and pathophysiology either at the primary site as well as in the areas of metastatic disease.

  5. PET in Lung Cancer

    Hans C. Steinert,

    2005-01-01

    Accurate tumor staging is essential for choosing the appropriate treatment strategy inpatients with lung cancer. It has already been shown that FDG-PET is highly accurate inclassifying lung nodules as benign or malignant. Integrated PET-CT enables the exactmatching of focal abnormalities on PET to anatomic structures on CT. PET-CT is superior indiagnostic accuracy for T staging and differentiation between tumor and peritumoral atelectasis.PET has also proved to be a very effective staging mod...

  6. Incidental tenosynovial huge cell tumors of the flexor hallucis longus muscle: seldom differential diagnosis of metabolic lesions using F18-FDG PET/CT; Inzidenteller tenosynovialer Riesenzelltumor des Musculus flexor hallucis longus. Seltene Differenzialdiagnose stoffwechselaktiver Laesionen in der F-18-FDG PET/CT

    Koestner, W.; Daemmrich, M.; Derlin, T.

    2016-03-15

    Tenosynovial huge cell tumors are seldom benign tumors in extremities originating from bone joint synovia and tendon sheats. In F18-FDG PET/CT imaging the tenosynovial huge cell tumors show increased metabolic activity and can trigger false diagnoses.

  7. 18F-fluorodeoxyglucose-PET/CT to evaluate tumor, nodal disease, and gross tumor volume of oropharyngeal and oral cavity cancer: comparison with MR imaging and validation with surgical specimen

    The purpose of this paper is to evaluate the impact of adding combined 18F-PET/CT to MRI for T and N staging of the oral and oropharyngeal cancer and calculation of the gross tumor volume (GTV) having histopathology as reference standard. PET/CT and MRI were performed in 66 patients with suspected oral and oropharyngeal cancer (41 primary tumors/25 recurrent tumors) and nodal disease (114 nodes). Statistical analysis included the McNemar test, sensitivity, specificity for the diagnostic modalities as well as regression analysis, and Bland-Altman graphs for calculated tumor volumes. There was no statistically significant difference between the two modalities compared to pathological findings regarding detection of disease (P≥0.72). The sensitivity/specificity for tumor detection were 100/80% and 96.72/60% for MRI and PET/CT, respectively. The sensitivity/specificity for nodal metastases were 88.46/75% and 83.81/73.91% for MRI and PET/CT, respectively. In 18% of cases, the MRI-based T staging resulted in an overestimation of the pathologic tumor stage. The corresponding rate for PET/CT was 22%. Regarding the treated necks, both modalities showed 100% sensitivity for detection of the recurrent lesions. In necks with histologically N0 staging, MRI and PET/CT gave 22% and 26% false positive findings, respectively. The mean tumor volume in the pathologic specimen was 16.6±18.6 ml, the mean volume derived by the MR imaging was 17.6±19.1 ml while the estimated by PET/CT volume was 18.8±18.1 ml (P≤0.007 between the three methods). The Bland-Altman analysis showed a better agreement between PET/CT and MRI. The diagnostic performance of FDG-PET/CT in the local staging of oral cancer is not superior to MRI. (orig.)

  8. Textural analysis of pre-therapeutic [18F]-FET-PET and its correlation with tumor grade and patient survival in high-grade gliomas

    Amino acid positron emission tomography (PET) with [18F]-fluoroethyl-L-tyrosine (FET) is well established in the diagnostic work-up of malignant brain tumors. Analysis of FET-PET data using tumor-to-background ratios (TBR) has been shown to be highly valuable for the detection of viable hypermetabolic brain tumor tissue; however, it has not proven equally useful for tumor grading. Recently, textural features in 18-fluorodeoxyglucose-PET have been proposed as a method to quantify the heterogeneity of glucose metabolism in a variety of tumor entities. Herein we evaluate whether textural FET-PET features are of utility for grading and prognostication in patients with high-grade gliomas. One hundred thirteen patients (70 men, 43 women) with histologically proven high-grade gliomas were included in this retrospective study. All patients received static FET-PET scans prior to first-line therapy. TBR (max and mean), volumetric parameters and textural parameters based on gray-level neighborhood difference matrices were derived from static FET-PET images. Receiver operating characteristic (ROC) and discriminant function analyses were used to assess the value for tumor grading. Kaplan-Meier curves and univariate and multivariate Cox regression were employed for analysis of progression-free and overall survival. All FET-PET textural parameters showed the ability to differentiate between World Health Organization (WHO) grade III and IV tumors (p < 0.001; AUC 0.775). Further improvement in discriminatory power was possible through a combination of texture and metabolic tumor volume, classifying 85 % of tumors correctly (AUC 0.830). TBR and volumetric parameters alone were correlated with tumor grade, but showed lower AUC values (0.644 and 0.710, respectively). Furthermore, a correlation of FET-PET texture but not TBR was shown with patient PFS and OS, proving significant in multivariate analysis as well. Volumetric parameters were predictive for OS, but this correlation did not

  9. Textural analysis of pre-therapeutic [18F]-FET-PET and its correlation with tumor grade and patient survival in high-grade gliomas

    Pyka, Thomas; Hiob, Daniela; Wester, Hans-Juergen [Klinikum Rechts der Isar der TU Muenchen, Department of Nuclear Medicine, Munich (Germany); Gempt, Jens; Ringel, Florian; Meyer, Bernhard [Klinikum Rechts der Isar der TU Muenchen, Neurosurgic Department, Munich (Germany); Schlegel, Juergen [Klinikum Rechts der Isar der TU Muenchen, Institute of Pathology and Neuropathology, Munich (Germany); Bette, Stefanie [Klinikum Rechts der Isar der TU Muenchen, Neuroradiologic department, Munich (Germany); Foerster, Stefan [Klinikum Rechts der Isar der TU Muenchen, Department of Nuclear Medicine, Munich (Germany); Klinikum Rechts der Isar der TU Muenchen, TUM Neuroimaging Center (TUM-NIC), Munich (Germany)

    2016-01-15

    Amino acid positron emission tomography (PET) with [18F]-fluoroethyl-L-tyrosine (FET) is well established in the diagnostic work-up of malignant brain tumors. Analysis of FET-PET data using tumor-to-background ratios (TBR) has been shown to be highly valuable for the detection of viable hypermetabolic brain tumor tissue; however, it has not proven equally useful for tumor grading. Recently, textural features in 18-fluorodeoxyglucose-PET have been proposed as a method to quantify the heterogeneity of glucose metabolism in a variety of tumor entities. Herein we evaluate whether textural FET-PET features are of utility for grading and prognostication in patients with high-grade gliomas. One hundred thirteen patients (70 men, 43 women) with histologically proven high-grade gliomas were included in this retrospective study. All patients received static FET-PET scans prior to first-line therapy. TBR (max and mean), volumetric parameters and textural parameters based on gray-level neighborhood difference matrices were derived from static FET-PET images. Receiver operating characteristic (ROC) and discriminant function analyses were used to assess the value for tumor grading. Kaplan-Meier curves and univariate and multivariate Cox regression were employed for analysis of progression-free and overall survival. All FET-PET textural parameters showed the ability to differentiate between World Health Organization (WHO) grade III and IV tumors (p < 0.001; AUC 0.775). Further improvement in discriminatory power was possible through a combination of texture and metabolic tumor volume, classifying 85 % of tumors correctly (AUC 0.830). TBR and volumetric parameters alone were correlated with tumor grade, but showed lower AUC values (0.644 and 0.710, respectively). Furthermore, a correlation of FET-PET texture but not TBR was shown with patient PFS and OS, proving significant in multivariate analysis as well. Volumetric parameters were predictive for OS, but this correlation did not

  10. Response evaluation of gastrointestinal stromal tumors treated with imatinib using 18F-FDG PET/CT

    Full text: Several studies have demonstrated the effective use of adjuvant treatment with Imatinib mesylate for unresectable, metastatic or recurrent Gastrointestinal Stromal Tumors (GIST). We retrospectively evaluated the role of 18F-FDG PET/CT scanning in assessing the response of GIST patients to imatinib mesylate therapy. Materials and Methods: Thirteen consecutive patients with GIST confirmed by surgery (5 stomach, 6 small bowel, 1 small bowel and peritoneum, and 1 rectum) underwent 60 18F-FDG PET/CT imaging before and after beginning imatinib mesylate therapy (400 mg/day or greater if disease progression). PET/CT scan was acquired 60 minutes after the intravenous injection of 333-707 MBq of 18F-FDG. Visual and semiquantitative (standardized uptake value (SUV)) analysis of images was performed. A decrease in SUV of more than 50% was considered as significant response, decrease in SUV of more than 25% was considered as partial response. Increase in SUV of more than 25% or appearance of new lesion (s) was considered as progression of disease. Response to therapy was assessed according to EORTC recommendations for PET. Results were confirmed by clinical follow-up, CECT findings or histological analysis (when available). Results: Complete response to imatinib mesylate was observed in 5 patients. Partial response and stable disease was noted in two each. Four patient demonstrated progression of disease, two developed liver metastasis, one developed abdominal lymphnode pathology and one had increase in size and uptake of tumor. Conclusion: 18F-FDG PET/CT scan identified the degree of GIST response to imatinib therapy. Patients who responded to therapy showed normalisation of FDG uptake or a decrease in the SUV of lesions. Patients with progression of disease demonstrated increase in uptake value or development of new lesion

  11. The role of whole-body FDG-PET in preoperative assessment of tumor staging in oral cancers

    The aim of this study is to clarify the clinical utility of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET) in determining the TNM classification in patients with oral cancer. Twenty-five consecutive patients (14 male and 11 female; age range, 40 yr to 86 yr) with oral cancer were included in this study. The diagnostic accuracy for detecting cervical lymph nodes was investigated by comparing the results of CT and/or MRI and physical findings. For the semi-quantitative analysis, the tumor standardized uptake value (SUV) and tumor to background SUV ratio (T/B ratio) were assessed in primary tumors and cervical lymph nodes. All primary lesions were visualized on FDG-PET images. Even though artifacts from dental materials near the lesion hampered the delineation of primary tumors on CT/MRI, the extent of primary tumors was accurately assessed by FDG-PET. The SUV and T/B ratio in the primary tumor classified in higher T grade (T3 and T4) was significantly higher than that in lower T grade (T1 and T2) (mean±SD of SUV; 8.32±2.99 vs. 5.15±3.77, p<0.01, mean ±SD of T/B ratio; 6.96±3.23 vs. 3.61±2.76, p<0.01). The SUV and T/B ratio of metastatic lymph nodes were also significantly higher than those of normal lymph nodes (mean ±SD of SUV; 3.39±1.69 vs. 1.55±0.57, p<0.001, mean ±SD of T/B ratio; 2.46±1.08 vs. 1.03±0.22, p<0.001). Among these three methods, FDG-PET in conjunction with CT/MRI showed the highest accuracy of 92%, but there were no significant differences in diagnostic accuracy among the three methods. For the semi-quantitative analysis, a threshold SUV of 2.0 provided 100% sensitivity, 82% specificity, and 88% accuracy. Furthermore, a threshold T/B ratio of 1.5 provided 100% sensitivity, 100% specificity, and 100% accuracy. Regarding the detection of distant metastasis, there was one positive result in FDG-PET showing distant pulmonary metastasis. Whole-body FDG-PET is an effective and convenient diagnostic tool for the

  12. A prospective, multicentre trial on the Value of {sup 18}F-FET PET in the post-therapeutic evaluation of childhood brain tumors; Prospektive, multizentrische Studie zur Bedeutung der O-(2-[{sup 18}F]Fluoroethyl)-L-Tyrosin-Positronen-Emissions-Tomografie (FET-PET) in der Verlaufsbeurteilung von Hirntumoren im Kindes- und Jugendalter (FET PET 2010). Vorstellung des Studiendesigns

    Plotkin, M.; Steffen, I.G. [Charite, Universitaetsmedizin Berlin (Germany). Klinik fuer Nuklearmedizin; Guggemos, A. [Kliniken der Stadt Koeln (Germany). Klinik fuer Kinder- und Jugendmedizin; Hernaiz Driever, P. [Charite, Universitaetsmedizin Berlin (Germany). Klinik fuer Paediatrie m.S. Onkologie/Haematologie

    2011-07-15

    We present a study concept of a prospective, multicentre trial on the value of {sup 18}F-FET PET in the post-therapeutic evaluation of childhood brain tumors (FET PET 2010). The main objective of this study is to evaluate the performance of {sup 18}F-FET PET in comparison to the MRI in differentiating residual tumor/recurrence from therapy-related changes in pediatric brain tumors after first line therapy. 160 patients will be recruited in this German multicenter study. Duration of study will be 3 years for all patients. (orig.)

  13. PET pharmacokinetic analysis to estimate boron concentration in tumor and brain as a guide to plan BNCT for malignant cerebral glioma

    Nariai, Tadashi [Department of Neurosurgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo (Japan)], E-mail: nariai.nsrg@tmd.ac.jp; Ishiwata, Kiichi [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1, Nakacho, Itabashi-ku, Tokyo (Japan); Kimura, Yuichi [Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba (Japan); Inaji, Motoki; Momose, Toshiya [Department of Neurosurgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo (Japan); Yamamoto, Tetsuya; Matsumura, Akira [Department of Neurosurgery, University of Tsukuba, Tennodai, Tsukuba, Igaraki (Japan); Ishii, Kenji [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1, Nakacho, Itabashi-ku, Tokyo (Japan); Ohno, Kikuo [Department of Neurosurgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo (Japan)

    2009-07-15

    Introduction: To plan the optimal BNCT for patients with malignant cerebral glioma, estimation of the ratio of boron concentration in tumor tissue against that in the surrounding normal brain (T/N ratio of boron) is important. We report a positron emission tomography (PET) imaging method to estimate T/N ratio of tissue boron concentration based on pharmacokinetic analysis of amino acid probes. Methods: Twelve patients with cerebral malignant glioma underwent 60 min dynamic PET scanning of brain after bolus injection of {sup 18}F-borono-phenyl-alanine (FBPA) with timed arterial blood sampling. Using kinetic parameter obtained by this scan, T/N ratio of boron concentration elicited by one-hour constant infusion of BPA, as performed in BNCT, was simulated on Runge-Kutta algorithm. {sup 11}C-methionine (MET) PET scan, which is commonly used in worldwide PET center as brain tumor imaging tool, was also performed on the same day to compare the image characteristics of FBPA and that of MET. Result: PET glioma images obtained with FBPA and MET are almost identical in all patients by visual inspection. Estimated T/N ratio of tissue boron concentration after one-hour constant infusion of BPA, T/N ratio of FBPA on static condition, and T/N ratio of MET on static condition showed significant linear correlation between each other. Conclusion: T/N ratio of boron concentration that is obtained by constant infusion of BPA during BNCT can be estimated by FBPA PET scan. This ratio can also be estimated by MET-PET imaging. As MET-PET study is available in many clinical PET center, selection of candidates for BNCT may be possible by MET-PET images. Accurate planning of BNCT may be performed by static images of FBPA PET. Use of PET imaging with amino acid probes may contribute very much to establish an appropriate application of BNCT for patients with malignant glioma.

  14. PET pharmacokinetic analysis to estimate boron concentration in tumor and brain as a guide to plan BNCT for malignant cerebral glioma

    Introduction: To plan the optimal BNCT for patients with malignant cerebral glioma, estimation of the ratio of boron concentration in tumor tissue against that in the surrounding normal brain (T/N ratio of boron) is important. We report a positron emission tomography (PET) imaging method to estimate T/N ratio of tissue boron concentration based on pharmacokinetic analysis of amino acid probes. Methods: Twelve patients with cerebral malignant glioma underwent 60 min dynamic PET scanning of brain after bolus injection of 18F-borono-phenyl-alanine (FBPA) with timed arterial blood sampling. Using kinetic parameter obtained by this scan, T/N ratio of boron concentration elicited by one-hour constant infusion of BPA, as performed in BNCT, was simulated on Runge-Kutta algorithm. 11C-methionine (MET) PET scan, which is commonly used in worldwide PET center as brain tumor imaging tool, was also performed on the same day to compare the image characteristics of FBPA and that of MET. Result: PET glioma images obtained with FBPA and MET are almost identical in all patients by visual inspection. Estimated T/N ratio of tissue boron concentration after one-hour constant infusion of BPA, T/N ratio of FBPA on static condition, and T/N ratio of MET on static condition showed significant linear correlation between each other. Conclusion: T/N ratio of boron concentration that is obtained by constant infusion of BPA during BNCT can be estimated by FBPA PET scan. This ratio can also be estimated by MET-PET imaging. As MET-PET study is available in many clinical PET center, selection of candidates for BNCT may be possible by MET-PET images. Accurate planning of BNCT may be performed by static images of FBPA PET. Use of PET imaging with amino acid probes may contribute very much to establish an appropriate application of BNCT for patients with malignant glioma.

  15. Stereotactic Comparison Study of 18F-Alfatide and 18F-FDG PET Imaging in an LLC Tumor-Bearing C57BL/6 Mouse Model

    Wei, Yu-Chun; Gao, Yongsheng; Zhang, Jianbo; Fu, Zheng; Zheng, Jinsong; Liu, Ning; Hu, Xudong; Hou, Wenhong; Yu, Jinming; Yuan, Shuanghu

    2016-01-01

    This study aimed to stereotactically compare the PET imaging performance of 18F-Alfatide (18F-ALF-NOTA-PRGD2, denoted as 18F-Alfatide) and 18F-fluorodeoxyglucose (FDG) and immunohistochemistry (IHC) staining in Lewis lung carcinoma (LLC) tumor-bearing C57BL/6 mouse model. 18F-FDG standard uptake values (SUVs) were higher than 18F-Alfatide SUVs in tumors, most of the normal tissues and organs except for the bladder. Tumor-to-brain, tumor-to-lung, and tumor-to-heart ratios of 18F-Alfatide PET were significantly higher than those of 18F-FDG PET (P SUV and GLUT-1 (R = 0.895, P SUV and αvβ3 (R = 0.595, P = 0.019), 18F-FDG SUV and 18F-Alfatide SUV (R = 0.917, P < 0.001), and GLUT-1 and αvβ3 (R = 0.637, P = 0.011). Therefore, 18F-Alfatide PET may be an effective tracer for tumor detection, spatial heterogeneity imaging and an alternative supplement to 18F-FDG PET, particularly for patients with enhanced characteristics in the brain, chest tumors or diabetes, meriting further study. PMID:27350554

  16. Stereotactic Comparison Study of (18)F-Alfatide and (18)F-FDG PET Imaging in an LLC Tumor-Bearing C57BL/6 Mouse Model.

    Wei, Yu-Chun; Gao, Yongsheng; Zhang, Jianbo; Fu, Zheng; Zheng, Jinsong; Liu, Ning; Hu, Xudong; Hou, Wenhong; Yu, Jinming; Yuan, Shuanghu

    2016-01-01

    This study aimed to stereotactically compare the PET imaging performance of (18)F-Alfatide ((18)F-ALF-NOTA-PRGD2, denoted as (18)F-Alfatide) and (18)F-fluorodeoxyglucose (FDG) and immunohistochemistry (IHC) staining in Lewis lung carcinoma (LLC) tumor-bearing C57BL/6 mouse model. (18)F-FDG standard uptake values (SUVs) were higher than (18)F-Alfatide SUVs in tumors, most of the normal tissues and organs except for the bladder. Tumor-to-brain, tumor-to-lung, and tumor-to-heart ratios of (18)F-Alfatide PET were significantly higher than those of (18)F-FDG PET (P SUV and GLUT-1 (R = 0.895, P SUV and αvβ3 (R = 0.595, P = 0.019), (18)F-FDG SUV and (18)F-Alfatide SUV (R = 0.917, P < 0.001), and GLUT-1 and αvβ3 (R = 0.637, P = 0.011). Therefore, (18)F-Alfatide PET may be an effective tracer for tumor detection, spatial heterogeneity imaging and an alternative supplement to (18)F-FDG PET, particularly for patients with enhanced characteristics in the brain, chest tumors or diabetes, meriting further study. PMID:27350554

  17. A novel metric for quantification of homogeneous and heterogeneous tumors in PET for enhanced clinical outcome prediction

    Rahmim, Arman; Schmidtlein, C. Ross; Jackson, Andrew; Sheikhbahaei, Sara; Marcus, Charles; Ashrafinia, Saeed; Soltani, Madjid; Subramaniam, Rathan M.

    2016-01-01

    Oncologic PET images provide valuable information that can enable enhanced prognosis of disease. Nonetheless, such information is simplified significantly in routine clinical assessment to meet workflow constraints. Examples of typical FDG PET metrics include: (i) SUVmax, (2) total lesion glycolysis (TLG), and (3) metabolic tumor volume (MTV). We have derived and implemented a novel metric for tumor quantification, inspired in essence by a model of generalized equivalent uniform dose as used in radiation therapy. The proposed metric, denoted generalized effective total uptake (gETU), is attractive as it encompasses the abovementioned commonly invoked metrics, and generalizes them, for both homogeneous and heterogeneous tumors, using a single parameter a. We evaluated this new metric for improved overall survival (OS) prediction on two different baseline FDG PET/CT datasets: (a) 113 patients with squamous cell cancer of the oropharynx, and (b) 72 patients with locally advanced pancreatic adenocarcinoma. Kaplan-Meier survival analysis was performed, where the subjects were subdivided into two groups using the median threshold, from which the hazard ratios (HR) were computed in Cox proportional hazards regression. For the oropharyngeal cancer dataset, MTV, TLG, SUVmax, SUVmean and SUVpeak produced HR values of 1.86, 3.02, 1.34, 1.36 and 1.62, while the proposed gETU metric for a  = 0.25 (greater emphasis on volume information) enabled significantly enhanced OS prediction with HR  =  3.94. For the pancreatic cancer dataset, MTV, TLG, SUVmax, SUVmean and SUVpeak resulted in HR values of 1.05, 1.25, 1.42, 1.45 and 1.52, while gETU at a  = 3.2 (greater emphasis on SUV information) arrived at an improved HR value of 1.61. Overall, the proposed methodology allows placement of differing degrees of emphasis on tumor volume versus uptake for different types of tumors to enable enhanced clinical outcome prediction.

  18. FDG-PET/CT for detection of the unknown primary head and neck tumor

    Johansen, J; Petersen, H; Godballe, Christian; Loft, Annika; Grau, Cai

    2011-01-01

    The benefit of FDG-PET in addition to standard work-up for carcinoma of unknown primary (CUP) and metastatic neck lesions has been widely described. However, most studies have been of retrospective nature with large heterogeneities in terms of workup standards and patient selection leaving several...... questions to be answered regarding the real value of PET in CUP. We here present an overview of the literature with focus on the current evidence of FDG-PET in detecting a primary in CUP and discuss the rationale of PET/CT in the diagnostic armamentarium of CUP....

  19. Prognostic value of defining the systemic tumor volume with FDG-PET in diffuse large b cell lymphoma

    We measured the systemic tumor volume using FDG-PET in patients with diffuse large B cell lymphoma (DLBL). We also investigated its prognostic role, and compared it with that of other prognostic factors. FDG PET was performed in 38 newly diagnosed DLBL patients (20 men, 18 women, age 55.715.1 years) at pre-treatment of chemotherapy. Clinical staging of lymphoma was evaluated by Ann Arbor system. On each FDG PET scan, we acquired volume of interest (VOl) at the cut-off value of SUV=2.5 in every measurable tumor by the automatic edge detection software. According to the VOI, we measured the metabolic volume and mean SUV, and estimated volume-activity indexes (SUV Vol) as mean SUV times metabolic volume. And then, we calculated the summed metabolic volume (VOLsum) and summed SUV Vol (SUV Volsum) in every FDG PET scan. Maximum SUV of involved lesion (SUVmax) was also acquired on each FDG PET scan. Time to treatment failure (TTF) was compared among VOLsum (median), SUV Volsum (median), SUVmax (median), clinical stage, gender, age, LDH, and performance status-assigned response designations by Kaplan-Meier survival analysis. Initial stages of DLBL patients were stage I in 4, II in 14, III in 15, and IV in 4 by Ann Arbor system. Median follow up period was 15.5months, and estimated mean TTF was 22.3 months. Univariate analysis demonstrated that TTF is statistically significantly reduced in those with high VOLsum (>215.1cm2, p=0.004), high SUV Volsum (>1577.5, p=0.003), and increased LDH (p=0.036). TTF did not correlate with SUVmax (p=0.571), clinical stage (p=0.194), gender (p=0.549), and age (p=0.128), and performance status =2 (p=0.074). Multivariate analysis using VOLsum, SUV Volsum, LDH, and performance status demonstrated no statistically significant predictor of TTF (p>0.05). Systemic tumor volume measurement using FDG-PET is suggestive to be the significant prognostic factor in patients with DLBL

  20. Molecular markers derived from bombesin for tumor diagnosis by SPECT and PET

    A high number of molecules have already been identified to have high affinity to some receptors overexpressed on tumour cells and the radiolabelling of those molecules offers the possibility of new compounds for tumour diagnosis and therapy by nuclear medicine. Among of those molecules, bombesin (BBN) has become focus of interest, as its BB2 receptors are known to be overexpressed in prostate, breast, colon, pancreatic and lung tumour, as long as glioblastomas and neuroblastomas. BBN agonists and antagonists have already been described for this purpose and promising results were obtained in preclinical studies. However, most of them exhibited high abdominal accumulation, especially in pancreas and intestines, which can compromise diagnosis accuracy and cause serious adverse effects in therapy. In this context, the goal of the present work to radiolabel new BBN derivatives with 111In and 68Ga and to evaluate their potential for BB2 positive tumors diagnosis by single photon emission tomography (SPECT) and positron emission tomography (PET). The structure of studied peptides was Q-YGn-BBN(6-14), where Q is the chelator, n is the number of glycine aminoacids in the spacer YGn and BBN(6-14) is the original bombesin sequence from the aminoacid 6 to 14. The derivative in which the last aminoacid (methionine, Met) was replaced by norleucine (Nle) was also evaluated. The experimental evaluation of the bombesin derivatives was divided into four steps: computational studies, molecular markers for SPECT, molecular markers for PET and toxicological studies. The theoretical partition (log P) and distribution (log D) coefficients were calculated for all bombesin derivatives conjugated to DTPA (diethylenetriaminepentaacetic acid) and DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) chelators applying computational programmes. Bombesin derivatives for SPECT were developed by radiolabelling DTPA-conjugated bombesin derivatives with 111In to determine the best spacer

  1. FDG-PET Response Prediction in Pediatric Hodgkin’s Lymphoma: Impact of Metabolically Defined Tumor Volumes and Individualized SUV Measurements on the Positive Predictive Value

    Background: In pediatric Hodgkin’s lymphoma (pHL) early response-to-therapy prediction is metabolically assessed by (18)F-FDG PET carrying an excellent negative predictive value (NPV) but an impaired positive predictive value (PPV). Aim of this study was to improve the PPV while keeping the optimal NPV. A comparison of different PET data analyses was performed applying individualized standardized uptake values (SUV), PET-derived metabolic tumor volume (MTV) and the product of both parameters, termed total lesion glycolysis (TLG); Methods: One-hundred-eight PET datasets (PET1, n = 54; PET2, n = 54) of 54 children were analysed by visual and semi-quantitative means. SUVmax, SUVmean, MTV and TLG were obtained the results of both PETs and the relative change from PET1 to PET2 (Δ in %) were compared for their capability of identifying responders and non-responders using receiver operating characteristics (ROC)-curves. In consideration of individual variations in noise and contrasts levels all parameters were additionally obtained after threshold correction to lean body mass and background; Results: All semi-quantitative SUV estimates obtained at PET2 were significantly superior to the visual PET2 analysis. However, ΔSUVmax revealed the best results (area under the curve, 0.92; p < 0.001; sensitivity 100%; specificity 85.4%; PPV 46.2%; NPV 100%; accuracy, 87.0%) but was not significantly superior to SUVmax-estimation at PET2 and ΔTLGmax. Likewise, the lean body mass and background individualization of the datasets did not impove the results of the ROC analyses; Conclusions: Sophisticated semi-quantitative PET measures in early response assessment of pHL patients do not perform significantly better than the previously proposed ΔSUVmax. All analytical strategies failed to improve the impaired PPV to a clinically acceptable level while preserving the excellent NPV

  2. FDG-PET Response Prediction in Pediatric Hodgkin’s Lymphoma: Impact of Metabolically Defined Tumor Volumes and Individualized SUV Measurements on the Positive Predictive Value

    Amr Elsayed M. Hussien

    2015-01-01

    Full Text Available Background: In pediatric Hodgkin’s lymphoma (pHL early response-to-therapy prediction is metabolically assessed by (18F-FDG PET carrying an excellent negative predictive value (NPV but an impaired positive predictive value (PPV. Aim of this study was to improve the PPV while keeping the optimal NPV. A comparison of different PET data analyses was performed applying individualized standardized uptake values (SUV, PET-derived metabolic tumor volume (MTV and the product of both parameters, termed total lesion glycolysis (TLG; Methods: One-hundred-eight PET datasets (PET1, n = 54; PET2, n = 54 of 54 children were analysed by visual and semi-quantitative means. SUVmax, SUVmean, MTV and TLG were obtained the results of both PETs and the relative change from PET1 to PET2 (Δ in % were compared for their capability of identifying responders and non-responders using receiver operating characteristics (ROC-curves. In consideration of individual variations in noise and contrasts levels all parameters were additionally obtained after threshold correction to lean body mass and background; Results: All semi-quantitative SUV estimates obtained at PET2 were significantly superior to the visual PET2 analysis. However, ΔSUVmax revealed the best results (area under the curve, 0.92; p < 0.001; sensitivity 100%; specificity 85.4%; PPV 46.2%; NPV 100%; accuracy, 87.0% but was not significantly superior to SUVmax-estimation at PET2 and ΔTLGmax. Likewise, the lean body mass and background individualization of the datasets did not impove the results of the ROC analyses; Conclusions: Sophisticated semi-quantitative PET measures in early response assessment of pHL patients do not perform significantly better than the previously proposed ΔSUVmax. All analytical strategies failed to improve the impaired PPV to a clinically acceptable level while preserving the excellent NPV.

  3. FDG-PET Response Prediction in Pediatric Hodgkin’s Lymphoma: Impact of Metabolically Defined Tumor Volumes and Individualized SUV Measurements on the Positive Predictive Value

    Hussien, Amr Elsayed M. [Department of Nuclear Medicine (KME), Forschungszentrum Jülich, Medical Faculty, Heinrich-Heine-University Düsseldorf, Jülich, 52426 (Germany); Department of Nuclear Medicine, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, 40225 (Germany); Furth, Christian [Department of Radiology and Nuclear Medicine, Medical School, Otto-von-Guericke University Magdeburg, Magdeburg, 39120 (Germany); Schönberger, Stefan [Department of Pediatric Oncology, Hematology and Clinical Immunology, University Children’s Hospital, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, 40225 (Germany); Hundsdoerfer, Patrick [Department of Pediatric Oncology and Hematology, Charité Campus Virchow, Humboldt-University Berlin, Berlin, 13353 (Germany); Steffen, Ingo G.; Amthauer, Holger [Department of Radiology and Nuclear Medicine, Medical School, Otto-von-Guericke University Magdeburg, Magdeburg, 39120 (Germany); Müller, Hans-Wilhelm; Hautzel, Hubertus, E-mail: h.hautzel@fz-juelich.de [Department of Nuclear Medicine (KME), Forschungszentrum Jülich, Medical Faculty, Heinrich-Heine-University Düsseldorf, Jülich, 52426 (Germany); Department of Nuclear Medicine, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, 40225 (Germany)

    2015-01-28

    Background: In pediatric Hodgkin’s lymphoma (pHL) early response-to-therapy prediction is metabolically assessed by (18)F-FDG PET carrying an excellent negative predictive value (NPV) but an impaired positive predictive value (PPV). Aim of this study was to improve the PPV while keeping the optimal NPV. A comparison of different PET data analyses was performed applying individualized standardized uptake values (SUV), PET-derived metabolic tumor volume (MTV) and the product of both parameters, termed total lesion glycolysis (TLG); Methods: One-hundred-eight PET datasets (PET1, n = 54; PET2, n = 54) of 54 children were analysed by visual and semi-quantitative means. SUVmax, SUVmean, MTV and TLG were obtained the results of both PETs and the relative change from PET1 to PET2 (Δ in %) were compared for their capability of identifying responders and non-responders using receiver operating characteristics (ROC)-curves. In consideration of individual variations in noise and contrasts levels all parameters were additionally obtained after threshold correction to lean body mass and background; Results: All semi-quantitative SUV estimates obtained at PET2 were significantly superior to the visual PET2 analysis. However, ΔSUVmax revealed the best results (area under the curve, 0.92; p < 0.001; sensitivity 100%; specificity 85.4%; PPV 46.2%; NPV 100%; accuracy, 87.0%) but was not significantly superior to SUVmax-estimation at PET2 and ΔTLGmax. Likewise, the lean body mass and background individualization of the datasets did not impove the results of the ROC analyses; Conclusions: Sophisticated semi-quantitative PET measures in early response assessment of pHL patients do not perform significantly better than the previously proposed ΔSUVmax. All analytical strategies failed to improve the impaired PPV to a clinically acceptable level while preserving the excellent NPV.

  4. Unusual association of alveolar rhabdomyosarcoma with pancreatic metastasis: emerging role of PET-CT in tumor staging

    Pancreatic metastases in childhood cancer have been rarely reported in the radiology literature although ample evidence exists in pathology reports for its occurrence in patients with alveolar rhabdomyosarcomas (RMS). Assess the occurrence of pancreatic metastases in alveolar rhabdomyosarcomas, increase awareness of this association and reassess current staging protocols. Three major oncology centers reviewed their records and imaging examinations. Patients' history and demographics, primary tumor site and histology, presence of tumor recurrence, and presence and location of other metastases were reviewed. Pancreatic metastases occurred in eight patients with alveolar RMS. Four of these presented at diagnosis and four with disease recurrence. In recurrent disease, the duration between the diagnosis of the primary tumor and pancreatic metastases varied from 8 months to 6 years (mean ± SD: 2.38 ± 2.49 years). In all patients who received PET scans, pancreatic metastases showed a marked FDG-uptake, but had variable detectability with CT. Pancreatic metastases were not associated with certain primary tumor locations or presence of other metastases, mandating an evaluation of the pancreas in all cases of alveolar rhabdomyosarcomas. Radiologists should be sensitized and actively evaluate the pancreas in patients with alveolar RMS. Optimizing CT and PET-CT protocols may increase the diagnostic yield. (orig.)

  5. Comparative evaluation of 18F-FDOPA, 13N-AMMONIA, 18F-FDG PET/CT and MRI in primary brain tumors - a pilot study

    To determine the diagnostic reliability of 18F-FDOPA, 13N-Ammonia and 18F-FDG PET/CT in primary brain tumors and comparison with magnetic resonance imaging (MRI). A total of 23 patients, 8 preoperative and 15 postoperative, undergoing evaluation for primary brain tumors were included in this study. Of them, 9/15 were operated for high grade gliomas (7/9 astrocytomas and 2/9 oligodendrogliomas) and 6/15 for low grade gliomas (5/6 astrocytomas and 1/6 oligodendroglioma). After PET study, 2 of 8 preoperative cases were histopathologically proven to be of benign etiology. 3 low grade and 2 high grade postoperative cases were disease free on 6 months follow-up. Tracer uptake was quantified by standardized uptake values (SUVmax) and the SUVmax ratio of tumor to normal symmetrical area of contra lateral hemisphere (T/N). 18F-FDOPA uptake was also quantified by SUVmax ratio of tumor to striatum (T/S). Conventional MR studies were done in all patients. Both high-grade and low-grade tumors were well visualized with 18F-FDOPA PET. Sensitivity of 18F-FDOPA PET was substantially higher (6/6 preoperative, 3/3 low grade postoperative, 7/7 high grade postoperative) than with 18F-FDG (3/6 preoperative, 1/3 low grade postoperative, 3/7 high grade postoperative) and 13N-Ammonia PET (2/6 preoperative, 1/3 low grade postoperative, 1/7 high grade postoperative). FDOPA was equally specific as FDG and Ammonia PET in operated cases but was falsely positive in two preoperative cases. Sensitivity of FDOPA (16/16) was more than MRI (13/16). 18F-FDG uptake correlates with tumor grade. Though 18F-FDOPA PET cannot distinguish between tumor grade, it is more reliable than 18F-FDG and 13N-Ammonia PET for evaluating brain tumors. 18F-FDOPA PET may prove to be superior to MRI in evaluating recurrence and residual tumor tissue. 13N-Ammonia PET did not show any encouraging results. (author)

  6. MicroPET imaging of brain tumor angiogenesis with {sup 18}F-labeled PEGylated RGD peptide

    Chen, Xiaoyuan; Park, Ryan; Hou, Yingping; Tohme, Michel; Bading, James R.; Conti, Peter S. [PET Imaging Science Center, Department of Radiology, University of Southern California Keck School of Medicine, 1510 San Pablo St., Suite 350, CA 90033, Los Angeles (United States); Khankaldyyan, Vazgen; Gonzales-Gomez, Ignacio; Laug, Walter E. [Department of Pediatrics, Childrens Hospital Los Angeles, CA 90027, Los Angeles (United States)

    2004-08-01

    We have previously labeled cyclic RGD peptide c(RGDyK) with fluorine-18 through conjugation labeling via a prosthetic 4-[{sup 18}F]fluorobenzoyl moiety and applied this [{sup 18}F]FB-RGD radiotracer for {alpha}{sub v}-integrin expression imaging in different preclinical tumor models with good tumor-to-background contrast. However, the unfavorable hepatobiliary excretion and rapid tumor washout rate of this tracer limit its potential clinical applications. The aims of this study were to modify the [{sup 18}F]FB-RGD tracer by inserting a heterobifunctional poly(ethylene glycol) (PEG, M.W. =3,400) between the {sup 18}F radiolabel and the RGD moiety and to test this [{sup 18}F]FB-PEG-RGD tracer for brain tumor targeting and in vivo kinetics. [{sup 18}F]FB-PEG-RGD was prepared by coupling the RGD-PEG conjugate with N-succinimidyl 4-[{sup 18}F]fluorobenzoate ([{sup 18}F]SFB) under slightly basic conditions (pH=8.5). The radiochemical yield was about 20-30% based on the active ester [{sup 18}F]SFB, and specific activity was over 100 GBq/{mu}mol. This tracer had fast blood clearance, rapid and high tumor uptake in the subcutaneous U87MG glioblastoma model (5.2{+-}0.5%ID/g at 30 min p.i.). Moderately rapid tumor washout was observed, with the activity accumulation decreased to 2.2{+-}0.4%ID/g at 4 h p.i. MicroPET and autoradiography imaging showed a very high tumor-to-background ratio and limited activity accumulation in the liver, kidneys and intestinal tracts. U87MG tumor implanted into the mouse forebrain was well visualized with [{sup 18}F]FB-PEG-RGD. Although uptake in the orthotopic tumor was significantly lower (P<0.01) than in the subcutaneous tumor, the maximum tumor-to-brain ratio still reached 5.0{+-}0.6 due to low normal brain background. The results of H and E staining post mortem agreed with the anatomical information obtained from non-invasive microPET imaging. In conclusion, PEGylation suitably modifies the physiological behavior of the RGD peptide. [{sup 18

  7. Reproducibility of 18F-FDG microPET Studies in Mouse Tumor Xenografts

    Dandekar, Mangal; Tseng, Jeffrey R.; Gambhir, Sanjiv S.

    2007-01-01

    18F-FDG has been used to image mouse xenograft models with small-animal PET for therapy response. However, the reproducibility of serial scans has not been determined. The purpose of this study was to determine the reproducibility of 18F-FDG small-animal PET studies.

  8. Comparison of the prognostic values of {sup 68}Ga-DOTANOC PET/CT and {sup 18}F-FDG PET/CT in patients with well-differentiated neuroendocrine tumor

    Sharma, Punit; Naswa, Niraj; Kc, Sudhir Suman; Yadav, Yashwant; Kumar, Rakesh; Bal, Chandrasekhar [All India Institute of Medical Sciences, Department of Nuclear Medicine, Ansari Nagar, New Delhi (India); Alvarado, Luis Andres; Dwivedi, Alok Kumar [Texas Tech University Health Sciences Center, Division of Biostatistics and Epidemiology, El Paso, TX (United States); Ammini, Ariachery C. [All India Institute of Medical Sciences, Department of Endocrinology and Metabolism, New Delhi (India)

    2014-12-15

    To determine the prognostic value of {sup 68}Ga-DOTANOC PET/CT in patients with well-differentiated neuroendocrine tumor (NET), and to compare the prognostic value with that of {sup 18}F-FDG PET/CT and other conventional clinicopathological prognostic factors. Data from 37 consecutive patients (age 46.6 ± 13.5 years, 51 % men) with well-differentiated NET who underwent {sup 68}Ga-DOTANOC PET/CT and {sup 18}F-FDG PET/CT were analyzed. All patients underwent a baseline visit with laboratory and radiological examinations. Clinical and imaging follow-up was performed in all patients. Progression-free survival (PFS) was measured from the date of the first PET/CT scan to the first documentation of progression of disease. {sup 68}Ga-DOTANOC PET/CT was positive in 37 of the 37 patients and {sup 18}F-FDG PET/CT was positive in 21. During follow-up 10 patients (27 %) showed progression of disease and 27 (73 %) showed no progression (24 stable disease, 3 partial response). The median follow-up was 25 months (range 2 - 52 months). Among the variables evaluated none was significantly different between the progressive disease and nonprogressive disease groups, with only SUVmax on {sup 68}Ga-DOTANOC PET/CT being borderline significant (P = 0.073). In the univariate analysis for PFS outcome, SUVmax on {sup 68}Ga-DOTANOC PET/CT (HR 0.122, 95 % CI 0.019 - 0.779; P = 0.026) and histopathological tumor grade (HR 4.238, 95 % CI 1.058 - 16.976; P = 0.041) were found to be associated with PFS. Other factors including age, sex, primary site, Ki-67 index, TNM stage, {sup 18}F-FDG PET/CT status (positive/negative), SUVmax on {sup 18}F-FDG PET/CT and type of treatment were not significant. In multivariable analysis, only SUVmax on {sup 68}Ga-DOTANOC PET/CT was found to be an independent positive predictor of PFS (HR 0.122, 95 % CI 0.019 - 0.779; P = 0.026). SUVmax measured on {sup 68}Ga-DOTANOC PET/CT is an independent, positive prognostic factor in patients with well-differentiated NET and

  9. Investigation of realistic PET simulations incorporating tumor patient's specificity using anthropomorphic models: Creation of an oncology database

    Purpose: The GATE Monte Carlo simulation toolkit is used for the implementation of realistic PET simulations incorporating tumor heterogeneous activity distributions. The reconstructed patient images include noise from the acquisition process, imaging system's performance restrictions and have limited spatial resolution. For those reasons, the measured intensity cannot be simply introduced in GATE simulations, to reproduce clinical data. Investigation of the heterogeneity distribution within tumors applying partial volume correction (PVC) algorithms was assessed. The purpose of the present study was to create a simulated oncology database based on clinical data with realistic intratumor uptake heterogeneity properties.Methods: PET/CT data of seven oncology patients were used in order to create a realistic tumor database investigating the heterogeneity activity distribution of the simulated tumors. The anthropomorphic models (NURBS based cardiac torso and Zubal phantoms) were adapted to the CT data of each patient, and the activity distribution was extracted from the respective PET data. The patient-specific models were simulated with the Monte Carlo Geant4 application for tomography emission (GATE) in three different levels for each case: (a) using homogeneous activity within the tumor, (b) using heterogeneous activity distribution in every voxel within the tumor as it was extracted from the PET image, and (c) using heterogeneous activity distribution corresponding to the clinical image following PVC. The three different types of simulated data in each case were reconstructed with two iterations and filtered with a 3D Gaussian postfilter, in order to simulate the intratumor heterogeneous uptake. Heterogeneity in all generated images was quantified using textural feature derived parameters in 3D according to the ground truth of the simulation, and compared to clinical measurements. Finally, profiles were plotted in central slices of the tumors, across lines with

  10. Pre-operative FDG PET/CT findings related to early tumor recurrence in breast cancer patients

    The purpose of this study was to identify any pre-operative FDG PET/CT findings related to early recurrence in the breast cancer patients. One hundred eighteen breast cancer patients who underwent 18F-FDG PET/CT scan for preoperative staging from September 2004 to September 2005 were included. All patients received operation and follow-up examination. From the FDG PET/CT images, (1) the peak standard uptake values (pSUV) of the primary tumor, (2) pSUV of axillary lymph node (LN) were recorded. 7 out of 118 patients had tumor recurrence within 26 months after the surgery. The mean pSUV of primary tumors with early recurrence (6.113.22) was significantly higher than the mean pSUV of the early recurrence negative follow-up group (3.432.43). The mean pSUVs of the axillary LN showed no significant difference between the early recurrence group and recurrence negative (2.122.17 vs 2.411.13). Of 111 patients with no evidence of recurrence, 71 patients showed no perceptible FDG uptake in the axillary LNs. On the other hand, all of the 7 recurrent breast cancer cases show increased FDG uptakes of axillary LN. In the recurrence negative group, no axillary LN demonstrated perceptibly increased FDG uptakes in 64% (71/111 cases); increased FDG uptake was noted in 36% (40/111 cases). In breast cancer patients who had early recurrence, the pSUV of the primary tumor was significantly higher than that of early recurrence negative patients. Though the pSUV of the axillary LN was not a predictor of recurrent breast cancer, all recurrent breast cancer patients had FDG uptake in axillary LN

  11. Systematic analysis of 18F-FDG PET and metabolism, proliferation and hypoxia markers for classification of head and neck tumors

    Quantification of molecular cell processes is important for prognostication and treatment individualization of head and neck cancer (HNC). However, individual tumor comparison can show discord in upregulation similarities when analyzing multiple biological mechanisms. Elaborate tumor characterization, integrating multiple pathways reflecting intrinsic and microenvironmental properties, may be beneficial to group most uniform tumors for treatment modification schemes. The goal of this study was to systematically analyze if immunohistochemical (IHC) assessment of molecular markers, involved in treatment resistance, and 18F-FDG PET parameters could accurately distinguish separate HNC tumors. Several imaging parameters and texture features for 18F-FDG small-animal PET and immunohistochemical markers related to metabolism, hypoxia, proliferation and tumor blood perfusion were assessed within groups of BALB/c nu/nu mice xenografted with 14 human HNC models. Classification methods were used to predict tumor line based on sets of parameters. We found that 18F-FDG PET could not differentiate between the tumor lines. On the contrary, combined IHC parameters could accurately allocate individual tumors to the correct model. From 9 analyzed IHC parameters, a cluster of 6 random parameters already classified 70.3% correctly. Combining all PET/IHC characteristics resulted in the highest tumor line classification accuracy (81.0%; cross validation 82.0%), which was just 2.2% higher (p = 5.2×10-32) than the performance of the IHC parameter/feature based model. With a select set of IHC markers representing cellular processes of metabolism, proliferation, hypoxia and perfusion, one can reliably distinguish between HNC tumor lines. Addition of 18F-FDG PET improves classification accuracy of IHC to a significant yet minor degree. These results may form a basis for development of tumor characterization models for treatment allocation purposes

  12. Can an FDG-PET/CT predict tumor clearance of the mesorectal fascia after preoperative chemoradiation of locally advanced rectal cancer?

    Vliegen, R.F.A.; Beets-Tan, R.G. [Dept. of Radiology, Univ. Hospital Maastricht (Netherlands); Vanhauten, B.; Oellers, M.; Buijsen, J.; Baardwijk, A. van; Ruysscher, D. de; Lammering, G. [Maastricht Radiation Oncology (Maastro), GROW, Univ. Hospital Maastricht (Netherlands); Driessen, A. [Dept. of Pathology, Univ. Hospital Maastricht (Netherlands); Kessels, A.G. [Dept. of Statistics, Univ. Hospital Maastricht (Netherlands); Arens, A. [Dept. of Nuclear Medicine, Univ. Hospital Maastricht (Netherlands); Beets, G.L. [Dept. of Surgery, Univ. Hospital Maastricht (Netherlands)

    2008-09-15

    Background and purpose: more effective preoperative treatment in locally advanced rectal cancer gives rise to a more individualized, conservative surgical treatment strategy. This, however, requires accurate information on tumor response after chemoradiation (CRT). So far, MRI and CT have failed to provide such information. Therefore, the value of a combined FDG-PET/CT in predicting tumor clearance of the mesorectal fascia (MRF) was determined. Patients and methods: 20 rectal cancer patients with MRF tumor invasion underwent preoperative PET/CT before and on average 6.3 weeks after CRT. The SUV{sub max} (maximal standard uptake value) on sequential PET/CT and the shortest distance between the outlined tumor volume and the MRF measured by using autocontouring software on post-CRT PET/CT were registered. The surgical specimen was evaluated for tumor clearance of the MRF and the tumor regression grade (TRG). Results: the TRG significantly corresponded with the SUV{sub max} changes induced by CRT (p = 0.025), and showed a trend with the post-CRT SUV{sub max} (TRG 1-2 vs. TRG 3-5: SUV{sub max} = 3.0 vs. 5.0; p = 0.06). However, the pathologically verified tumor clearance of the MRF was not correlated with any of the tested SUV parameters nor with the shortest distance between the residual tumor and the MRF. Conclusion: post-CRT PET/CT is not a useful tool for evaluating anatomic tumor changes and, therefore, not accurate in predicting tumor clearance of the MRF. However, it might be a useful tool in predicting pathologic tumor response after CRT. (orig.)

  13. Tumor uptake of 68Ga-DOTA-Tyr3-octreotate: animal PET studies of tumor flow and acute somatostatin receptor modulation in the CA20948 rat model

    Introduction: Factors determining the in vivo uptake of radiolabeled somatostatin analogs by neuroendocrine tumors are poorly known. The aim is to evaluate in vivo tumor perfusion and regulation of somatostatin receptors (sstr) following acute exposure to octreotide, in an animal model of neuroendocrine tumor. Methods: H215O flow studies were performed in 8 CA20948 tumor-bearing rats and another 36 rats underwent three [68Ga]-DOTA-Tyr3-octreotate imaging sessions at 24-h intervals. After baseline (Day 0) imaging, scanning was repeated on Day 1 after octreotide injection (175 μg/kg), with a variable delay: no injection (controls, n=7), coinjection (n=6), and octreotide injection 20 min (n=7), 2 h (n=8) and 4 h (n=8) before imaging. Repeat images without octreotide was performed at Day 2 followed by sacrifice and tumor counting. Results: H215O studies failed to measure quantitative tumor perfusion in this model. On Day 1, ratio of tumor uptake to Day 0 was 1.2±0.3 in controls; 0.6±0.2 in the coinjection group; 0.9±0.2, 1.1±0.1 and 1.2±0.2 in the other groups, respectively. Uptake in the coinjection group showed a statistically significant reduction of tumor uptake (P2=0.946). Conclusion: Acute exposure to unlabeled octreotide in this neuroendocrine tumor model results in a rapid recycling or resynthesis of sstr. Positron emission tomography (PET) allowed to reliably assess quantitative uptake of [68Ga]-DOTA-Tyr3-octreotate over time in the same animal, but failed in this model to measure tumor perfusion.

  14. Leptomeningeal carcinomatosis as only pathological finding at FDG-PET/CT in case of tumor marker elevation in breast cancer

    Leptomeningeal carcinomatosis is an infrequent disease and although its treatment is palliative, earlier diagnosis will lead to prolonged survival and improve functional outcome. Whole-body FDG-PET allows the entire spinal cord to be examined noninvasively, so close attention should be paid to the spinal canal, since these lesions can easily be mistaken for physiologic uptake, sometimes there is no clinical suspicion and may occur without concurrent active cancer. We present a female patient with a history of carcinoma of the breast, who presented an elevation of serum tumor marker CA 15-3. An FDG-PET/CT study only revealed multiple abnormal uptake at the vertebral foramen at thoracic and lumbosacral regions suggesting leptomeningeal metastases that were confirmed by MRI and cerebrospinal fluid cytology

  15. Giant Cell Tumor Pulmonary Metastases Mimic Primary malignant Pulmonary Nodules on 18F FDG PET/CT

    A 59-year-old man with a 30-year history of multiple recurrences of a giant cell tumor (GCT) of the left knee was referred for an 18F-FDG PET/CT to evaluate a solitary pulmonary nodule. The nodule was mildly FDG-avid, raising suspicion of malignancy. It was excised and histologically proven to be a GCT pulmonary metastasis. A follow-up PET/CT done 2 years later revealed a new, larger lung mass that was more intensely FDG-avid, but of the same histology. This rare report highlights a pitfall in the evaluation of solitary pulmonary lesions by 18F-FDG PCT/CT in patients with GCT of the bone

  16. SU-E-J-249: Characterization of Gynecological Tumor Heterogeneity Using Texture Analysis in the Context of An 18F-FDG PET Adaptive Protocol

    Nawrocki, J [Duke University Medical Physics Graduate Program, Durham, NC (United States); Chino, J; Craciunescu, O [Duke University Medical Center Department of Radiation Oncology, Durham, NC (United States); Das, S [University of North Carolina School of Medicine, Chapel Hill, NC (United States)

    2015-06-15

    Purpose: We propose a method to examine gynecological tumor heterogeneity using texture analysis in the context of an adaptive PET protocol in order to establish if texture metrics from baseline PET-CT predict tumor response better than SUV metrics alone as well as determine texture features correlating with tumor response during radiation therapy. Methods: This IRB approved protocol included 29 women with node positive gynecological cancers visible on FDG-PET treated with EBRT to the PET positive nodes. A baseline and intra-treatment PET-CT was obtained. Tumor outcome was determined based on RECIST on posttreatment PET-CT. Primary GTVs were segmented using 40% threshold and a semi-automatic gradient-based contouring tool, PET Edge (MIM Software Inc., Cleveland, OH). SUV histogram features, Metabolic Volume (MV), and Total Lesion Glycolysis (TLG) were calculated. Four 3D texture matrices describing local and regional relationships between voxel intensities in the GTV were generated: co-occurrence, run length, size zone, and neighborhood difference. From these, 39 texture features were calculated. Prognostic power of baseline features derived from gradientbased and threshold GTVs were determined using the Wilcoxon rank-sum test. Receiver Operating Characteristics and logistic regression was performed using JMP (SAS Institute Inc., Cary, NC) to find probabilities of predicting response. Changes in features during treatment were determined using the Wilcoxon signed-rank test. Results: Of the 29 patients, there were 16 complete responders, 7 partial responders, and 6 non-responders. Comparing CR/PR vs. NR for gradient-based GTVs, 7 texture values, TLG, and SUV kurtosis had a p < 0.05. Threshold GTVs yielded 4 texture features and TLG with p < 0.05. From baseline to intra-treatment, 14 texture features, SUVmean, SUVmax, MV, and TLG changed with p < 0.05. Conclusion: Texture analysis of PET imaged gynecological tumors is an effective method for early prognosis and should

  17. SU-E-J-249: Characterization of Gynecological Tumor Heterogeneity Using Texture Analysis in the Context of An 18F-FDG PET Adaptive Protocol

    Purpose: We propose a method to examine gynecological tumor heterogeneity using texture analysis in the context of an adaptive PET protocol in order to establish if texture metrics from baseline PET-CT predict tumor response better than SUV metrics alone as well as determine texture features correlating with tumor response during radiation therapy. Methods: This IRB approved protocol included 29 women with node positive gynecological cancers visible on FDG-PET treated with EBRT to the PET positive nodes. A baseline and intra-treatment PET-CT was obtained. Tumor outcome was determined based on RECIST on posttreatment PET-CT. Primary GTVs were segmented using 40% threshold and a semi-automatic gradient-based contouring tool, PET Edge (MIM Software Inc., Cleveland, OH). SUV histogram features, Metabolic Volume (MV), and Total Lesion Glycolysis (TLG) were calculated. Four 3D texture matrices describing local and regional relationships between voxel intensities in the GTV were generated: co-occurrence, run length, size zone, and neighborhood difference. From these, 39 texture features were calculated. Prognostic power of baseline features derived from gradientbased and threshold GTVs were determined using the Wilcoxon rank-sum test. Receiver Operating Characteristics and logistic regression was performed using JMP (SAS Institute Inc., Cary, NC) to find probabilities of predicting response. Changes in features during treatment were determined using the Wilcoxon signed-rank test. Results: Of the 29 patients, there were 16 complete responders, 7 partial responders, and 6 non-responders. Comparing CR/PR vs. NR for gradient-based GTVs, 7 texture values, TLG, and SUV kurtosis had a p < 0.05. Threshold GTVs yielded 4 texture features and TLG with p < 0.05. From baseline to intra-treatment, 14 texture features, SUVmean, SUVmax, MV, and TLG changed with p < 0.05. Conclusion: Texture analysis of PET imaged gynecological tumors is an effective method for early prognosis and should

  18. Clinical impact of [18F]FDG-PET in patients with suspected recurrent breast cancer based on asymptomatically elevated tumor marker serum levels. A preliminary report

    The purpose of this study was to evaluate retrospectively the impact of [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) on the detection of recurrent breast cancer based on asymptomatically elevated tumor markers levels. Whole-body FDG-PET was performed in 30 patients with suspected recurrent breast cancer and asymptomatic tumor marker increase but negative or equivocal other imaging modality results. A blood sample was drawn in each case for marker assay (CA 15-3 and CEA) on the same day as the FDG-PET. All of these 30 asymptomatic patients had either CA 15-3>32 U/ml or CEA>5 ng/ml. The final diagnosis of recurrent breast cancer was established by operation/biopsy histopathological findings or clinical follow-up for >1 year by additional morphological imaging techniques. Among the 30 patients, the final diagnosis of recurrent breast cancer was established in 38 sites in 28 patients. FDG-PET accurately detected 35/38 sites in 25/28 patients with recurrence. The diagnostic sensitivity and accuracy of FDG-PET in patients with suspected recurrent breast cancer and asymptomatically elevated tumor markers were 96 and 90%, respectively. FDG-PET is a useful technique for detecting recurrent breast cancer suspected from asymptomatically elevated tumor markers levels and has an important clinical impact on the management of these patients. (author)

  19. 18F-FAMT uptake correlates with tumor proliferative activity in oral squamous cell carcinoma. Comparative study with 18F-FDG PET and immunohistochemistry

    L-3-[18F]-fluoro-α-methyl tyrosine (FAMT) is transported into cancer cells by L-type amino acid transporter 1 (LAT1). The purpose of the present study is to correlate the uptake of FAMT and fluorodeoxyglucose (FDG) with the cellular proliferative activity measured by the Ki-67 labeling index (Ki-67 LI) in oral squamous cell carcinoma (OSCC). Twenty-five patients with OSCC were enrolled in this study. Both FAMT-positron emission tomography (PET) and FDG-PET were performed within 4 weeks before surgery in all cases. The uptake of FAMT and FDG was compared by semiquantitative analysis with maximal standardized uptake values (SUVmax) of the primary tumors. Ki-67 LI of the tumors was analyzed by immunohistochemical staining and correlated with the clinicopathologic variables and the uptake of PET tracers. For primary tumor detection, FAMT-PET exhibited a sensitivity of 84%, whereas that of FDG-PET was 88%. In all visible lesions, mean FDG uptake determined by average SUVmax was 9.7 (range 4.2-15.9) and mean FAMT uptake was 3.5 (range 1.3-8.5). The SUVmax of FAMT tended to show a better correlation with Ki-67 LI (r=0.878) than that of FDG (r=0.643). Uptake of FAMT correlated with cellular proliferation of OSCC. FAMT-PET may be a useful procedure to evaluate tumor proliferation of OSCC. (author)

  20. SU-C-9A-03: Simultaneous Deconvolution and Segmentation for PET Tumor Delineation Using a Variational Method

    Li, L; Tan, S [Huazhong University of Science and Technology, Wuhan, Hubei (China); Lu, W; D' Souza, W [University of Maryland School of Medicine, Baltimore, MD (United States)

    2014-06-01

    Purpose: To implement a new method that integrates deconvolution with segmentation under the variational framework for PET tumor delineation. Methods: Deconvolution and segmentation are both challenging problems in image processing. The partial volume effect (PVE) makes tumor boundaries in PET image blurred which affects the accuracy of tumor segmentation. Deconvolution aims to obtain a PVE-free image, which can help to improve the segmentation accuracy. Conversely, a correct localization of the object boundaries is helpful to estimate the blur kernel, and thus assist in the deconvolution. In this study, we proposed to solve the two problems simultaneously using a variational method so that they can benefit each other. The energy functional consists of a fidelity term and a regularization term, and the blur kernel was limited to be the isotropic Gaussian kernel. We minimized the energy functional by solving the associated Euler-Lagrange equations and taking the derivative with respect to the parameters of the kernel function. An alternate minimization method was used to iterate between segmentation, deconvolution and blur-kernel recovery. The performance of the proposed method was tested on clinic PET images of patients with non-Hodgkin's lymphoma, and compared with seven other segmentation methods using the dice similarity index (DSI) and volume error (VE). Results: Among all segmentation methods, the proposed one (DSI=0.81, VE=0.05) has the highest accuracy, followed by the active contours without edges (DSI=0.81, VE=0.25), while other methods including the Graph Cut and the Mumford-Shah (MS) method have lower accuracy. A visual inspection shows that the proposed method localizes the real tumor contour very well. Conclusion: The result showed that deconvolution and segmentation can contribute to each other. The proposed variational method solve the two problems simultaneously, and leads to a high performance for tumor segmentation in PET. This work was

  1. Quantitation and visualization of tumor-specific T cells in the secondary lymphoid organs during and after tumor elimination by PET

    Matsui, Ken; Wang Zheng; McCarthy, Timothy J.; Allen, Paul M.; Reichert, David E. E-mail: ReichertD@wustl.edu

    2004-11-01

    Increased understanding in the area of trafficking behavior of adoptively transferred tumor-specific T cells could help develop better therapeutic protocols. We utilized the DUC18/CMS5 tumor model system in conjunction with a microPET scanner to study the DUC18 T cell distribution pattern in spleens and lymph nodes in live mice. Anti-Thy1.2 antibodies conjugated to 1,4,7,10-tetraazacyclododecane-N,N',N'',N''-tetraacetic acid (DOTA) and radiolabeled with {sup 64}Cu were administered to three groups of BALB-Thy1.1 mice on days 4, 7, or 14 post-DUC18 T cell transfer. We were able to detect the transferred cells in all the major lymph nodes, spleens, and in tumors. Our findings suggest that tumor-specific T cells do not all preferentially localize to the tumors but they also home to all the major lymphoid organs; additionally the number of DUC18 T cells remains relatively constant during and after tumor elimination within each lymphoid organ.

  2. FDG PET/CT imaging of desmoplastic small round cell tumor: findings at staging, during treatment and at follow-up

    Desmoplastic small round cell tumor (DSRCT) is a very uncommon soft-tissue tumor of children and young adults. It has an aggressive course with generally poor survival. In general the assessment of tumor burden and response has relied upon CT or MRI. However these tumors are often metabolically active and can be evaluated using FDG PET/CT imaging. The purpose of this study was to determine the metabolic activity of desmoplastic small round cell tumors using FDG PET/CT imaging and the potential utility of FDG PET/CT in this disease. Eight patients (seven male, one female; ages 2-20 years, median 11 years) with confirmed DSRCT underwent 82 positron emission tomography/computed tomography (PET/CT) scans. PET/CT was used for initial staging (seven patients, eight scans), monitoring response to therapy (eight patients, 37 scans) and for surveillance of DSRCT recurrence (six patients, 37 scans). Each scan performed at diagnosis showed abnormally elevated uptake in the primary tumor. Five patients had abdominal pelvic involvement, and two of those also had thoracic disease. Six patients whose scans showed no abnormal sites of uptake at the end of therapy have had progression-free survivals of 2-10 years. One patient whose scan continued to show uptake during treatment died of disease 1.3 years from diagnosis. Another patient with persistent uptake remained in treatment 3 years after initial diagnosis. One surveillance scan identified recurrent disease. FDG PET/CT identified elevated metabolic activity in each patient studied. Despite our small sample size, FDG PET/CT scans appear useful for the management of patients with DSCRT. Patients whose studies become negative during or following treatment may have a prolonged remission. (orig.)

  3. FDG PET/CT imaging of desmoplastic small round cell tumor: findings at staging, during treatment and at follow-up

    Ostermeier, Austin; Snyder, Scott E.; Shulkin, Barry L. [St. Jude Children' s Research Hospital, Department of Radiological Sciences, MS 220, Memphis, TN (United States); McCarville, M.B. [St. Jude Children' s Research Hospital, Department of Radiological Sciences, MS 220, Memphis, TN (United States); College of Medicine, University of Tennessee Health Science Center, Department of Radiology, Memphis, TN (United States); Navid, Fariba [St. Jude Children' s Research Hospital, Department of Oncology, Memphis, TN (United States); University of Tennessee Health Science Center, Department of Pediatrics, College of Medicine, Memphis, TN (United States)

    2015-08-15

    Desmoplastic small round cell tumor (DSRCT) is a very uncommon soft-tissue tumor of children and young adults. It has an aggressive course with generally poor survival. In general the assessment of tumor burden and response has relied upon CT or MRI. However these tumors are often metabolically active and can be evaluated using FDG PET/CT imaging. The purpose of this study was to determine the metabolic activity of desmoplastic small round cell tumors using FDG PET/CT imaging and the potential utility of FDG PET/CT in this disease. Eight patients (seven male, one female; ages 2-20 years, median 11 years) with confirmed DSRCT underwent 82 positron emission tomography/computed tomography (PET/CT) scans. PET/CT was used for initial staging (seven patients, eight scans), monitoring response to therapy (eight patients, 37 scans) and for surveillance of DSRCT recurrence (six patients, 37 scans). Each scan performed at diagnosis showed abnormally elevated uptake in the primary tumor. Five patients had abdominal pelvic involvement, and two of those also had thoracic disease. Six patients whose scans showed no abnormal sites of uptake at the end of therapy have had progression-free survivals of 2-10 years. One patient whose scan continued to show uptake during treatment died of disease 1.3 years from diagnosis. Another patient with persistent uptake remained in treatment 3 years after initial diagnosis. One surveillance scan identified recurrent disease. FDG PET/CT identified elevated metabolic activity in each patient studied. Despite our small sample size, FDG PET/CT scans appear useful for the management of patients with DSCRT. Patients whose studies become negative during or following treatment may have a prolonged remission. (orig.)

  4. 68Ga-DOTA-NGR as a novel molecular probe for APN-positive tumor imaging using MicroPET

    Aminopeptidase N (APN) is selectively expressed on many tumors and the endothelium of tumor neovasculature, and may serve as a promising target for cancer diagnosis and therapy. Asparagine–glycine–arginine (NGR) peptides have been shown to bind specifically to the APN receptor and have served as vehicles for the delivery of various therapeutic drugs in previous studies. The purpose of this study was to synthesize and evaluate the efficacy of a 68Ga-labeled NGR peptide as a new molecular probe that binds to APN. Methods: NGR peptide was conjugated with 1,4,7,10-tetraazacyclododecane-N,N’,N”,N”’-tetraacetic acid (DOTA) and labeled with 68Ga at 95 °C for 10 min. In vitro uptake and binding analysis was performed with A549 and MDA-MB231 cells. Biodistribution of 68Ga-DOTA-NGR was determined in normal mice by dissection method. 68Ga-DOTA-NGR PET was performed in A549 and MDA-MB231 xenografts, and included dynamic and static imaging. APN expression in tumors and new vasculatures was analyzed by immunohistochemistry. Results: The radiochemical purity of 68Ga-DOTA-NGR was 98.0% ± 1.4% with a specific activity of about 17.49 MBq/nmol. The uptake of 68Ga-DOTA-NGR in A549 cells increased with longer incubation times, and could be blocked by cold DOTA-NGR, while no specific uptake was found in MDA-MB231 cells. In vivo biodistribution studies showed that 68Ga-DOTA-NGR was mainly excreted from the kidney, and rapidly cleared from blood and nonspecific organs. MicroPET imaging showed that high focal accumulation had occurred in the tumor site at 1 h post-injection (pi) in A549 tumor xenografts. A significant reduction of tumor uptake was observed following coinjection with a blocking dose of DOTA-NGR, whereas only mild uptake was found in MDA-MB231 tumor xenografts. Tumor uptake, measured as the tumor/lung ratio, increased with time peaking at 12.58 ± 1.26 at 1.5 h pi. Immunohistochemical staining confirmed that APN was overexpressed on A549 cells and

  5. Retroperitoneal bronchogenic cyst presenting paraadrenal tumor incidentally detected by {sup 18}F-FDG PET/CT

    Yoon, Ye Ri; Choi, Ji Youn; Lee, Sang Mi; Kim, Yeo Joo; Cho, Hyun Deuk; Lee, Jeong Won; Jeon, Youn Soo [Soonchunhyang University Cheonan Hospital, Cheonan (Korea, Republic of)

    2015-03-15

    A follow-up 18F-fluorodeoxyglucose ({sup 18}F-FDG) PET/CT scan of a 57-year-old asymptomatic male who had undergone total thyroidectomy for thyroid cancer revealed a 5.0 x 4.0-cm, well-defined, ovoid-shaped mass around the left adrenal gland without definite FDG uptake. On the adrenal CT scan, the left paraadrenal tumor showed high attenuation on the precontrast scan without enhancement. The average Hounsfield unit (HU) was 58.1 on the precontrast scan and 58.4 on the postcontrast scan. The patient underwent laparoscopic adrenalectomy for resection of the left paraadrenal tumor. The final histopathologic examination revealed a bronchogenic cyst. Although retroperitoneal bronchogenic cysts are rare, they should be considered in the differential diagnosis of retroperitoneal cystic tumors. The preoperative diagnosis is difficult, but a contrast-enhanced CT scan or {sup 18}F-FDG PET/CT scan may be useful for differentiating hyperattenuated cysts from other soft tissue masses.

  6. PET imaging of tumor neovascularization in a transgenic mouse model with a novel 64Cu-DOTA-knottin peptide

    Nielsen, Carsten Haagen; Kimura, Richard H; Withofs, Nadia;

    2010-01-01

    the knottin peptide are compared with standard 18F-fluorodeoxyglucose (FDG) PET small animal imaging. Lung nodules as small as 3 mm in diameter were successfully identified in the transgenic mice by small animal CT, and both 64Cu-DOTA-knottin 2.5F and FDG were able to differentiate lung nodules from...... the surrounding tissues. Uptake and retention of the 64Cu-DOTA-knottin 2.5F tracer in the lung tumors combined with a low background in the thorax resulted in a statistically higher tumor to background (normal lung) ratio compared with FDG (6.01±0.61 versus 4.36±0.68; P...... animal CT followed by characterization with the use of small animal PET with a novel 64Cu-1,4,7,10-tetra-azacylododecane-N,N',N'',N'''-tetraacetic acid (DOTA)-knottin peptide that targets integrins upregulated during angiogenesis on the tumor associated neovasculature. The imaging results obtained with...

  7. Comparison of 18F PET and 99mTc SPECT imaging in phantoms and in tumored mice.

    Cheng, Dengfeng; Wang, Yi; Liu, Xinrong; Pretorius, P Hendrik; Liang, Minmin; Rusckowski, Mary; Hnatowich, Donald J

    2010-08-18

    Our objective was to compare the performance of a micro-single photon emission computed tomography (micro-SPECT) with that of a micro-positron emission tomography (microPET) in a Her2+ tumored mice using an anti-Her2 nanoparticle radiolabeled with (99m)Tc and (18)F. Camera performance was first compared using phantoms; then a tumored mouse administered the (99m)Tc-nanoparticle was imaged on a Bioscan NanoSPECT/CT, while another tumored mouse received the identical nanoparticle, labeled now with (18)F, and was imaged on a Philips Mosaic HP PET camera. The nanoparticle was radiolabeled with (99m)Tc via MAG(3) chelation and with (18)F via SFB as an intermediate. Phantom imaging showed that the resolution of the SPECT camera was clearly superior, but even with 4 heads and multipinhole collimators, detection sensitivity was 15-fold lower. Radiolabeling of the nanoparticle by chelation with (99m)Tc was considerably easier and safer than manual covalent attachment of (18)F. Both cameras provided accurate quantitation of radioactivity over a broad range. In conclusion, when deciding between (99m)Tc vs (18)F, an advantage rests with the chelation of (99m)Tc over covalent attachment of (18)F, achieved manually or otherwise, but with these small animal cameras, this choice also results in trading lower sensitivity for higher resolution. PMID:20681508

  8. Inter-modality variation in gross tumor volume delineation in 18FDG-PET guided IMRT treatment planning for lung cancer.

    Song, Yulin; Chan, Maria; Burman, Chandra; Cann, Donald

    2006-01-01

    Rapid advances in 18FDG-PET/CT technology and novel co-registration algorithms have created a strong interest in 18FDG-PET/CT's application in intensity modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT). Accurate target volume delineation, particularly identification of pathologically positive lymph nodes, could translate into favorable treatment outcome. However, gross tumor volume (GTV) delineation on both CT and 18FDG-PET is very sensitive to observer variation. The objectives of the study were to investigate the inter-modality variation in gross tumor volume delineation defined by two imaging modalities for lung cancer: CT and 18FDG-PET/CT and its dosimetric implications in intensity modulated radiation therapy (IMRT). PMID:17946204

  9. Early prediction of therapy response and disease free survival after induction chemotherapy in stage III non-small cell lung cancer by FDG-PET: Correlation between tumor FDG-metabolism and morphometric tumor response

    Aim: Chemotherapy with Docetaxel and Carboplatin (DC) has shown high response rates in advanced non-small cell lung cancer (NSCLC). Histologic tumor response after chemotherapy or combined chemoradiotherapy is strongly associated with systemic tumor control and potentially cure. Metabolic tumor response assessed by FDG-PET after induction VIP-chemotherapy has been shown to be predictive of outcome in NSCLC. The aim of the present study was to correlate the tumor FDG metabolism as measured by F-18 FDG-PET with morphometric findings after DC induction chemotherapy plus Erythropoietin (10,000 IU Epo s.c. three times a week). Material and Methods: In this prospective multicenter study, 54 patients with NSCLC stage IIIA (9 patients) or IIIB (45 patients) were enrolled and received neoadjuvant treatment with D 100 mg/m2 d1 and C AUC 7.5 d2 q21 days for 4 cycles prior to surgery. Postoperatively, all patients received adjuvant radiotherapy. WB-PET-studies (ECAT Exact 47) were obtained p.i. of 400 MBq F-18 FDG. Standardized uptake values (SUV), metabolic tumor diameter (MTD) and metabolic tumor index (MTI SUV x MTD) were assessed. Image fusion of PET and CT data was applied on a HERMES computer. Results: Of 54 enrolled patients, 46 were evaluable for response by CT. 30/46 patients (65%) achieved complete remission (CR, 1 patient) or partial remission (PR 29 patients.). Of the 46 patients, 37 patients completed neoadjuvant chemotherapy (Chx) and were studied before and after Chx by FDG-PET. 14 (30% of the 46 evaluable patients) had SUV < 2.5, corresponding to metabolic complete remission (mCR), 23 had PR or stable disease (non-mCR); in 9 patients, PET was not performed because of progressive disease demonstrated by CT. The R0-resection rate was 56% (27/48 evaluable patients). Of the 14 patients with metabolic CR, 9 were evaluated by morphometry. All had regression grades III (no vital tumor cells) or grade IIB (< 10% vital tumor cells and induced apoptosis). With a median

  10. Ga-68 DOTATOC PET/CT-Guided Biopsy and Cryoablation with Autoradiography of Biopsy Specimen for Treatment of Tumor-Induced Osteomalacia.

    Maybody, Majid; Grewal, Ravinder K; Healey, John H; Antonescu, Cristina R; Fanchon, Louise; Hwang, Sinchun; Carrasquillo, Jorge A; Kirov, Assen; Farooki, Azeez

    2016-09-01

    Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by small benign tumors of mesenchymal origin also known as phosphaturic mesenchymal tumors mixed connective tissue variant. Excellent prognosis is expected with eradication of the culprit tumor. These small tumors are notoriously difficult to localize with conventional imaging studies; this often leads to an extensive work up and prolonged morbidity. We report a patient with clinical diagnosis of TIO whose culprit tumor was localized with Ga-68 DOTATOC PET/CT and MRI. Biopsy and cryoablation were performed under Ga-68 DOTATOC PET/CT guidance. Autoradiography of the biopsy specimen was performed and showed in situ correlation between Ga-68 DOTATOC uptake and histopathology with millimeter resolution. PMID:27150801

  11. Impact of patient weight on tumor visibility based on human-shaped phantom simulation study in PET imaging system

    Energy window technique has been implemented in all positron emission tomography (PET) imaging protocol, with the aim to remove the unwanted low energy photons. Current practices in our institution however are performed by using default energy threshold level regardless of the weight of the patient. Phantom size, which represents the size of the patient's body, is the factor that determined the level of scatter fraction during PET imaging. Thus, the motivation of this study is to determine the optimum energy threshold level for different sizes of human-shaped phantom, to represent underweight, normal, overweight and obese patients. In this study, the scanner was modeled by using Monte Carlo code, version MCNP5. Five different sizes of elliptical-cylinder shaped of human-sized phantoms with diameter ranged from 15 to 30 cm were modeled. The tumor was modeled by a cylindrical line source filled with 1.02 MeV positron emitters at the center of the phantom. Various energy window widths, in the ranged of 10–50% were implemented to the data. In conclusion, the phantom mass volume did influence the scatter fraction within the volume. Bigger phantom caused more scattering events and thus led to coincidence counts lost. We evaluated the impact of phantom sizes on the sensitivity and visibility of the simulated models. Implementation of wider energy window improved the sensitivity of the system and retained the coincidence photons lost. Visibility of the tumor improved as an appropriate energy window implemented for the different sizes of phantom. - Highlights: • Optimizing the energy window improved the sensitivity of the PET system. • Improving the visibility of the tumors using the optimized energy window. • Recommendations on the optimized energy windows for different body sizes. • Using simulated phantom using MCNP to determine various body sizes

  12. FDG-PET for Evaluating the Antitumor Effect of Intraarterial 3-Bromopyruvate Administration in a Rabbit VX2 Liver Tumor Model

    Park, Hee Sun; Chung, Jin Wook; Jae, Hwan Jun; Kim, Young Il; Son, Kyu Ri; Lee, Min Jong; Park, Jae Hyung; Kang, Won Jun; Yoon, Jung Hwan; Chung, Hesson; Lee, Kichang

    2007-01-01

    Objective We wanted to investigate the feasibility of using FDG-PET for evaluating the antitumor effect of intraarterial administration of a hexokinase II inhibitor, 3-bromopyruvate (3-BrPA), in a rabbit VX2 liver tumor model. Materials and Methods VX2 carcinoma was grown in the livers of ten rabbits. Two weeks later, liver CT was performed to confirm appropriate tumor growth for the experiment. After tumor volume-matched grouping of the rabbits, transcatheter intraarterial administration of ...

  13. One-step radiosynthesis of 18F-AlF-NOTA-RGD2 for tumor angiogenesis PET imaging

    One of the major obstacles of the clinical translation of 18F-labeled arginine-glycine-aspartic acid (RGD) peptides has been the laborious multistep radiosynthesis. In order to facilitate the application of RGD-based positron emission tomography (PET) probes in the clinical setting we investigated in this study the feasibility of using the chelation reaction between Al18F and a macrocyclic chelator-conjugated dimeric RGD peptide as a simple one-step 18F labeling strategy for development of a PET probe for tumor angiogenesis imaging. Dimeric cyclic peptide E[c(RGDyK)]2 (RGD2) was first conjugated with a macrocyclic chelator, 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA), and the resulting bioconjugate NOTA-RGD2 was then radiofluorinated via Al18F intermediate to synthesize 18F-AlF-NOTA-RGD2. Integrin binding affinities of the peptides were assessed by a U87MG cell-based receptor binding assay using 125I-echistatin as the radioligand. The tumor targeting efficacy and in vivo profile of 18F-AlF-NOTA-RGD2 were further evaluated in a subcutaneous U87MG glioblastoma xenograft model by microPET and biodistribution. NOTA-RGD2 was successfully 18F-fluorinated with good yield within 40 min using the Al18F intermediate. The IC50 of 19F-AlF-NOTA-RGD2 was determined to be 46 ± 4.4 nM. Quantitative microPET studies demonstrated that 18F-AlF-NOTA-RGD2 showed high tumor uptake, fast clearance from the body, and good tumor to normal organ ratios. NOTA-RGD2 bioconjugate has been successfully prepared and labeled with Al18F in one single step of radiosynthesis. The favorable in vivo performance and the short radiosynthetic route of 18F-AlF-NOTA-RGD2 warrant further optimization of the probe and the radiofluorination strategy to accelerate the clinical translation of 18F-labeled RGD peptides. (orig.)

  14. Staging of cervical cancer based on tumor heterogeneity characterized by texture features on 18F-FDG PET images

    Mu, Wei; Chen, Zhe; Liang, Ying; Shen, Wei; Yang, Feng; Dai, Ruwei; Wu, Ning; Tian, Jie

    2015-07-01

    The aim of the study is to assess the staging value of the tumor heterogeneity characterized by texture features and other commonly used semi-quantitative indices extracted from 18F-FDG PET images of cervical cancer (CC) patients. Forty-two patients suffering CC at different stages were enrolled in this study. Firstly, we proposed a new tumor segmentation method by combining the intensity and gradient field information in a level set framework. Secondly, fifty-four 3D texture features were studied besides of SUVs (SUVmax, SUVmean, SUVpeak) and metabolic tumor volume (MTV). Through correlation analysis, receiver-operating-characteristic (ROC) curves analysis, some independent indices showed statistically significant differences between the early stage (ES, stages I and II) and the advanced stage (AS, stages III and IV). Then the tumors represented by those independent indices could be automatically classified into ES and AS, and the most discriminative feature could be chosen. Finally, the robustness of the optimal index with respect to sampling schemes and the quality of the PET images were validated. Using the proposed segmentation method, the dice similarity coefficient and Hausdorff distance were 91.78   ±   1.66% and 7.94   ±   1.99 mm, respectively. According to the correlation analysis, all the fifty-eight indices could be divided into 20 groups. Six independent indices were selected for their highest areas under the ROC curves (AUROC), and showed significant differences between ES and AS (P  Pearson correlation of RP under different sampling schemes is 0.9991   ±   0.0011. RP is a highly stable feature and well correlated with tumor stage in CC, which suggests it could differentiate ES and AS with high accuracy.

  15. Desmoplastic small round cell tumor: impact of 18F-FDG PET induced treatment strategy in a patient with long-term outcome

    Alessio Imperiale

    2009-07-01

    Full Text Available The desmoplastic small round cell tumor (DSRCT is an uncommon and highly aggressive cancer. The role of 18F-FDG PET in management of DSRCT is little reported. We report a case of metastasized abdominal DSRCT detected in a 43-year old patient whose diagnostic and therapeutic approaches were influenced by 18F-FDG PET-CT. The patient is still alive ten years after diagnosis. 18F-FDG PET-CT seems to be a useful method for assessing therapeutic efficiency and detecting early recurrences even in rare malignancies such as DSRCT.

  16. In Vivo Phenotyping of Tumor Metabolism in a Canine Cancer Patient with Simultaneous 18F-FDG-PET and Hyperpolarized 13C-Pyruvate Magnetic Resonance Spectroscopic Imaging (hyperPET: Mismatch Demonstrates that FDG may not Always Reflect the Warburg Effect

    Henrik Gutte

    2015-06-01

    Full Text Available In this communication the mismatch between simultaneous 18F-FDG-PET and a 13C-lactate imaging (hyperPET in a biopsy verified squamous cell carcinoma in the right tonsil of a canine cancer patient is shown. The results demonstrate that 18F-FDG-PET may not always reflect the Warburg effect in all tumors.

  17. Which FDG/PET parameters of the primary tumors in colon or sigmoid cancer provide the best correlation with the pathological findings?

    Chen, Shang-Wen, E-mail: vincent1680616@yahoo.com.tw [Department of Radiation Oncology, China Medical University Hospital, No. 2, Yuh-Der Road, Taichung 404, Taiwan (China); Graduate Institute of Clinical Medicine Science and School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan (China); School of Medicine, Taipei Medical University, Taipei, Taiwan (China); Chen, William Tzu-Liang, E-mail: wtchen@mail.cmuh.org.tw [Department of Surgery, China Medical University Hospital, No. 2, Yuh-Der Road, Taichung 404, Taiwan (China); Wu, Yi-Chen, E-mail: ed101302@edah.org.tw [Department of Nuclear Medicine, E-DA Hospital, I-Shou University, No. 1, Yida Road, Jiaosu, Yanchao, Kaohsiung 82445, Taiwan (China); Yen, Kuo-Yang, E-mail: cruise_ann@yahoo.com.tw [Department of Nuclear Medicine and PET Center, China Medical University Hospital, No. 2, Yuh-Der Road, Taichung 404, Taiwan (China); Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan (China); Hsieh, Te-Chun, E-mail: d10119@mail.cmuh.org.tw [Department of Nuclear Medicine and PET Center, China Medical University Hospital, No. 2, Yuh-Der Road, Taichung 404, Taiwan (China); Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan (China); Lin, Tze-Yi, E-mail: tylin.tw@msa.hinet.net [Department of Pathology, China Medical University Hospital, No. 2, Yuh-Der Road, Taichung 404, Taiwan (China); Kao, Chia-Hung, E-mail: d10040@mail.cmuh.org.tw [Department of Nuclear Medicine and PET Center, China Medical University Hospital, No. 2, Yuh-Der Road, Taichung 404, Taiwan (China); Graduate Institute of Clinical Medicine Science and School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan (China)

    2013-09-15

    Background To compare {sup 18}F-fluoro-2-deoxdeoxyglucose (FDG) positron emission tomography (PET) related parameters of primary colon or sigmoid cancer (CSC) with pathological findings. Methods Seventy-seven CSC patients who have undergone preoperative PET computed tomograms (PET/CT) are included in this study. Maximum PET-based tumor length (TL) and tumor width (TW) are determined using several auto-segmentation methods, and various thresholds of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are measured. The PET-based TL and TW are compared with maximum pathological length and width on the pathological specimen. Results Using a 30% threshold level for maximum uptake of TL (TL30%) and TW (TW30%) yield results that provide an optimal match with maximum pathological length (R = 0.81, p < 0.001) and width (R = 0.70, p < 0.001). TW30% was an independent factor for predicting pathological T3 or T4 stages (OR = 1.26, 95% CI = 1.07–1.47, p = 0.01). The receiver-operating characteristic curves show MTV at a fixed threshold of 40% maximum uptake (MTV40%), and TW30% achieved better correlation with the advanced pathological T stage. No associations with positive N stage were observed. Conclusion Pretreatment PET/CT is a useful tool for predicting the final pathological findings for CSC patients requiring surgical procedures.

  18. Which FDG/PET parameters of the primary tumors in colon or sigmoid cancer provide the best correlation with the pathological findings?

    Background To compare 18F-fluoro-2-deoxdeoxyglucose (FDG) positron emission tomography (PET) related parameters of primary colon or sigmoid cancer (CSC) with pathological findings. Methods Seventy-seven CSC patients who have undergone preoperative PET computed tomograms (PET/CT) are included in this study. Maximum PET-based tumor length (TL) and tumor width (TW) are determined using several auto-segmentation methods, and various thresholds of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are measured. The PET-based TL and TW are compared with maximum pathological length and width on the pathological specimen. Results Using a 30% threshold level for maximum uptake of TL (TL30%) and TW (TW30%) yield results that provide an optimal match with maximum pathological length (R = 0.81, p < 0.001) and width (R = 0.70, p < 0.001). TW30% was an independent factor for predicting pathological T3 or T4 stages (OR = 1.26, 95% CI = 1.07–1.47, p = 0.01). The receiver-operating characteristic curves show MTV at a fixed threshold of 40% maximum uptake (MTV40%), and TW30% achieved better correlation with the advanced pathological T stage. No associations with positive N stage were observed. Conclusion Pretreatment PET/CT is a useful tool for predicting the final pathological findings for CSC patients requiring surgical procedures

  19. Metabolic impact of partial volume correction of [18F]FDG PET-CT oncological studies on the assessment of tumor response to treatment

    The aim of this work is to evaluate the metabolic impact of Partial Volume Correction (PVC) on the measurement of the Standard Uptake Value (SUV) from [18F]FDG PET-CT oncological studies for treatment monitoring purpose. Twenty-nine breast cancer patients with bone lesions (42 lesions in total) underwent [18F]FDG PET-CT studies after surgical resection of breast cancer primitives, and before (PET-I) and after (PET-II) chemotherapy and hormone treatment. PVC of bone lesion uptake was performed on the two [18F]FDG PET-CT studies, using a method based on Recovery Coefficients (RC) and on an automatic measurement of lesion metabolic volume. Body-weight average SUV was calculated for each lesion, with and without PVC. The accuracy, reproducibility, clinical feasibility and the metabolic impact on treatment response of the considered PVC method was evaluated. The PVC method was found clinically feasible in bone lesions, with an accuracy of 93% for lesion sphere-equivalent diameter >1 cm. Applying PVC, average SUV values increased, from 7% up to 154% considering both PET-I and PET-II studies, proving the need of the correction. As main finding, PVC modified the therapy response classification in 6 cases according to EORTC 1999 classification and in 5 cases according to PERCIST 1.0 classification. In conclusion, PVC has an important metabolic impact on the assessment of tumor response to treatment by [18F]FDG PET-CT oncological studies

  20. Malignant extrarenal rhabdoid tumor of the spine: staging and evaluation of response to therapy with F-18 FDG PET/CT.

    Makis, William; Ciarallo, Anthony; Hickeson, Marc

    2011-07-01

    Malignant extrarenal rhabdoid tumor (ERRT) is a very rare type of soft-tissue sarcoma with a reported incidence of 0.3% of all soft-tissue sarcomas. Only 7 cases of spinal malignant ERRT have been reported in the literature, and to our knowledge, F-18 FDG PET/CT imaging for staging and evaluation of response to therapy for these tumors has not been previously described. This is a case of an 8-month-old boy with malignant ERRT of the spine, who was staged with F-18 FDG PET/CT, and had his tumor burden assessed with PET/CT after chemotherapy, which altered the subsequent chemotherapy regimen. PMID:21637073

  1. {sup 18}F-FLT and {sup 18}F-FDOPA PET kinetics in recurrent brain tumors

    Wardak, Mirwais; Schiepers, Christiaan; Dahlbom, Magnus; Phelps, Michael E.; Huang, Sung-Cheng [David Geffen School of Medicine at UCLA, Department of Molecular and Medical Pharmacology, Los Angeles, CA (United States); Cloughesy, Timothy F. [David Geffen School of Medicine at UCLA, Department of Neurology, Los Angeles, CA (United States)

    2014-06-15

    In this study, kinetic parameters of the cellular proliferation tracer {sup 18}F-3'-deoxy-3'-fluoro-l-thymidine (FLT) and the amino acid probe 3,4-dihydroxy-6-{sup 18}F-fluoro-l-phenylalanine (FDOPA) were measured before and early after the start of therapy, and were used to predict the overall survival (OS) of patients with recurrent malignant glioma using multiple linear regression (MLR) analysis. High-grade recurrent brain tumors in 21 patients (11 men and 10 women, age range 26 - 76 years) were investigated. Each patient had three dynamic PET studies with each probe: at baseline and after 2 and 6 weeks from the start of treatment. Treatment consisted of biweekly cycles of bevacizumab (an angiogenesis inhibitor) and irinotecan (a chemotherapeutic agent). For each study, about 3.5 mCi of FLT (or FDOPA) was administered intravenously and dynamic PET images were acquired for 1 h (or 35 min for FDOPA). A total of 126 PET scans were analyzed. A three-compartment, two-tissue model was applied to estimate tumor FLT and FDOPA kinetic rate constants using a metabolite- and partial volume-corrected input function. MLR analysis was used to model OS as a function of FLT and FDOPA kinetic parameters for each of the three studies as well as their relative changes between studies. An exhaustive search of MLR models using three or fewer predictor variables was performed to find the best models. Kinetic parameters from FLT were more predictive of OS than those from FDOPA. The three-predictor MLR model derived using information from both probes (adjusted R{sup 2} = 0.83) fitted the OS data better than that derived using information from FDOPA alone (adjusted R{sup 2} = 0.41), but was only marginally different from that derived using information from FLT alone (adjusted R{sup 2} = 0.82). Standardized uptake values (either from FLT alone, FDOPA alone, or both together) gave inferior predictive results (best adjusted R{sup 2} = 0.25). For recurrent malignant glioma treated

  2. Tumor hypoxia and microscopic diffusion capacity in brain tumors: A comparison of 62Cu-Diacetyl-Bis (N4-Methylthiosemicarbazone) PET/CT and diffusion-weighted MR imaging

    The aim of this study was to clarify the relationship between tumor hypoxia and microscopic diffusion capacity in primary brain tumors using 62Cu-Diacetyl-Bis (N4-Methylthiosemicarbazone) (62Cu-ATSM) PET/CT and diffusion-weighted MR imaging (DWI). This study was approved by the institutional human research committee and was HIPAA compliant, and informed consent was obtained from all patients. 62Cu-ATSM PET/CT and DWI were performed in a total of 40 primary brain tumors of 34 patients with low grade glioma (LGG, n = 13), glioblastoma (GBM, n = 20), and primary central nervous system lymphoma (PCNSL, n = 7). 62Cu-ATSM PET/CT parameters and apparent diffusion coefficient (ADC) obtained by DWI were compared. High intensity signals by 62Cu-ATSM PET/CT and DWI in patients with GBM and PCNSL, and low intensity signals in LGG patients were observed. An inverse correlation was found between maximum SUV (SUVmax) and minimum ADC (ADCmin) (r = -0.583, p ratio) and ADCmin for all tumors (r = -0.532, p max and T/Bratio in GBM were higher than LGG (p min was lower in GBM (p = 0.011) and PCNSL (p = 0.01) than in LGG, while no significant difference was found between GBM and PCNSL (p = 0.90). Tumor hypoxia assessed by 62Cu-ATSM PET/CT correlated with microscopic diffusion capacity obtained by DWI in brain tumors. Both 62Cu-ATSM PET/CT and DWI were considered feasible imaging methods for grading glioma. However, 62Cu-ATSM PET/CT provided additional diagnostic information to differentiate between GBM and PCNSL. (orig.)

  3. Multiparametric Monitoring of Early Response to Antiangiogenic Therapy: A Sequential Perfusion CT and PET/CT Study in a Rabbit VX2 Tumor Model

    Jung Im Kim

    2014-01-01

    Full Text Available Objectives. To perform dual analysis of tumor perfusion and glucose metabolism using perfusion CT and FDG-PET/CT for the purpose of monitoring the early response to bevacizumab therapy in rabbit VX2 tumor models and to assess added value of FDG-PET to perfusion CT. Methods. Twenty-four VX2 carcinoma tumors implanted in bilateral back muscles of 12 rabbits were evaluated. Serial concurrent perfusion CT and FDG-PET/CT were performed before and 3, 7, and 14 days after bevacizumab therapy (treatment group or saline infusion (control group. Perfusion CT was analyzed to calculate blood flow (BF, blood volume (BV, and permeability surface area product (PS; FDG-PET was analyzed to calculate SUVmax, SUVmean, total lesion glycolysis (TLG, entropy, and homogeneity. The flow-metabolic ratio (FMR was also calculated and immunohistochemical analysis of microvessel density (MVD was performed. Results. On day 14, BF and BV in the treatment group were significantly lower than in the control group. There were no significant differences in all FDG-PET-derived parameters between both groups. In the treatment group, FMR prominently decreased after therapy and was positively correlated with MVD. Conclusions. In VX2 tumors, FMR could provide further insight into the early antiangiogenic effect reflecting a mismatch in intratumor blood flow and metabolism.

  4. Usefulness of [18F]FDG-PET in diagnosis of bone and soft tissue tumors. Study with multi-center survey by questionnaire

    In the aspect of future additional approval of [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) diagnosis of the title tumors in the health insurance, its usefulness was studied by questionnaire to 18 facilities, where PET had been conducted for those tumors in the period July, 2005-February, 2006. Major questions concerned the purpose and finding of PET, findings by other imaging and by tumor markers, and judgment of PET effectiveness compared with other imaging (more useful, equally or less, and its reason). Subjects were 75 cases (42 males, 33 females; 3-82 years old) in 20 diseases, which involved 21 cases of osteosarcoma, 7 of leiomyosarcoma, 8 of Ewing sarcoma, 6 of liposarcoma, 5 of hemangiosarcoma, 4 of synovial sarcoma, each 3 of rhabdomyosarcoma, giant cell tumor, Schwannoma, malignant fibrous histiocytoma, each 2 of chondrosarcoma, alveolar soft part sarcoma, each one of epithelioid sarcoma, endometrial storomal sarcoma, hibernoma, fibrosarcoma, multiple osteochondroma, sacral chondroma, Langerhans cell histiocytosis and neurofibromatosis. Obtained were the judgments of highly useful in 5 diseases, fairly useful in 4, useful in 3, and useful/inconclusive due to the only one case in 8. FDG-PET was thus found useful in all diseases examined. (R.T.)

  5. SU-C-9A-01: Parameter Optimization in Adaptive Region-Growing for Tumor Segmentation in PET

    Purpose: To design a reliable method to determine the optimal parameter in the adaptive region-growing (ARG) algorithm for tumor segmentation in PET. Methods: The ARG uses an adaptive similarity criterion m - fσ ≤ I-PET ≤ m + fσ, so that a neighboring voxel is appended to the region based on its similarity to the current region. When increasing the relaxing factor f (f ≥ 0), the resulting volumes monotonically increased with a sharp increase when the region just grew into the background. The optimal f that separates the tumor from the background is defined as the first point with the local maximum curvature on an Error function fitted to the f-volume curve. The ARG was tested on a tumor segmentation Benchmark that includes ten lung cancer patients with 3D pathologic tumor volume as ground truth. For comparison, the widely used 42% and 50% SUVmax thresholding, Otsu optimal thresholding, Active Contours (AC), Geodesic Active Contours (GAC), and Graph Cuts (GC) methods were tested. The dice similarity index (DSI), volume error (VE), and maximum axis length error (MALE) were calculated to evaluate the segmentation accuracy. Results: The ARG provided the highest accuracy among all tested methods. Specifically, the ARG has an average DSI, VE, and MALE of 0.71, 0.29, and 0.16, respectively, better than the absolute 42% thresholding (DSI=0.67, VE= 0.57, and MALE=0.23), the relative 42% thresholding (DSI=0.62, VE= 0.41, and MALE=0.23), the absolute 50% thresholding (DSI=0.62, VE=0.48, and MALE=0.21), the relative 50% thresholding (DSI=0.48, VE=0.54, and MALE=0.26), OTSU (DSI=0.44, VE=0.63, and MALE=0.30), AC (DSI=0.46, VE= 0.85, and MALE=0.47), GAC (DSI=0.40, VE= 0.85, and MALE=0.46) and GC (DSI=0.66, VE= 0.54, and MALE=0.21) methods. Conclusions: The results suggest that the proposed method reliably identified the optimal relaxing factor in ARG for tumor segmentation in PET. This work was supported in part by National Cancer Institute Grant R01 CA172638; The

  6. SU-C-9A-01: Parameter Optimization in Adaptive Region-Growing for Tumor Segmentation in PET

    Tan, S [University of Maryland School of Medicine, Baltimore, MD (United States); Huazhong University of Science and Technology, Wuhan, Hubei (China); Xue, M; Chen, W; D' Souza, W; Lu, W [University of Maryland School of Medicine, Baltimore, MD (United States); Li, H [Washington University School of Medicine, Saint Louis, MO. (United States)

    2014-06-01

    Purpose: To design a reliable method to determine the optimal parameter in the adaptive region-growing (ARG) algorithm for tumor segmentation in PET. Methods: The ARG uses an adaptive similarity criterion m - fσ ≤ I-PET ≤ m + fσ, so that a neighboring voxel is appended to the region based on its similarity to the current region. When increasing the relaxing factor f (f ≥ 0), the resulting volumes monotonically increased with a sharp increase when the region just grew into the background. The optimal f that separates the tumor from the background is defined as the first point with the local maximum curvature on an Error function fitted to the f-volume curve. The ARG was tested on a tumor segmentation Benchmark that includes ten lung cancer patients with 3D pathologic tumor volume as ground truth. For comparison, the widely used 42% and 50% SUVmax thresholding, Otsu optimal thresholding, Active Contours (AC), Geodesic Active Contours (GAC), and Graph Cuts (GC) methods were tested. The dice similarity index (DSI), volume error (VE), and maximum axis length error (MALE) were calculated to evaluate the segmentation accuracy. Results: The ARG provided the highest accuracy among all tested methods. Specifically, the ARG has an average DSI, VE, and MALE of 0.71, 0.29, and 0.16, respectively, better than the absolute 42% thresholding (DSI=0.67, VE= 0.57, and MALE=0.23), the relative 42% thresholding (DSI=0.62, VE= 0.41, and MALE=0.23), the absolute 50% thresholding (DSI=0.62, VE=0.48, and MALE=0.21), the relative 50% thresholding (DSI=0.48, VE=0.54, and MALE=0.26), OTSU (DSI=0.44, VE=0.63, and MALE=0.30), AC (DSI=0.46, VE= 0.85, and MALE=0.47), GAC (DSI=0.40, VE= 0.85, and MALE=0.46) and GC (DSI=0.66, VE= 0.54, and MALE=0.21) methods. Conclusions: The results suggest that the proposed method reliably identified the optimal relaxing factor in ARG for tumor segmentation in PET. This work was supported in part by National Cancer Institute Grant R01 CA172638; The

  7. Can hypoxia-PET map hypoxic cell density heterogeneity accurately in an animal tumor model at a clinically obtainable image contrast?

    Background: PET allows non-invasive mapping of tumor hypoxia, but the combination of low resolution, slow tracer adduct-formation and slow clearance of unbound tracer remains problematic. Using a murine tumor with a hypoxic fraction within the clinical range and a tracer post-injection sampling time that results in clinically obtainable tumor-to-reference tissue activity ratios, we have analyzed to what extent inherent limitations actually compromise the validity of PET-generated hypoxia maps. Materials and methods: Mice bearing SCCVII tumors were injected with the PET hypoxia-marker fluoroazomycin arabinoside (FAZA), and the immunologically detectable hypoxia marker, pimonidazole. Tumors and reference tissue (muscle, blood) were harvested 0.5, 2 and 4 h after FAZA administration. Tumors were analyzed for global (well counter) and regional (autoradiography) tracer distribution and compared to pimonidazole as visualized using immunofluorescence microscopy. Results: Hypoxic fraction as measured by pimonidazole staining ranged from 0.09 to 0.32. FAZA tumor to reference tissue ratios were close to unity 0.5 h post-injection but reached values of 2 and 6 when tracer distribution time was prolonged to 2 and 4 h, respectively. A fine-scale pixel-by-pixel comparison of autoradiograms and immunofluorescence images revealed a clear spatial link between FAZA and pimonidazole-adduct signal intensities at 2 h and later. Furthermore, when using a pixel size that mimics the resolution in PET, an excellent correlation between pixel FAZA mean intensity and density of hypoxic cells was observed already at 2 h post-injection. Conclusions: Despite inherent weaknesses, PET-hypoxia imaging is able to generate quantitative tumor maps that accurately reflect the underlying microscopic reality (i.e., hypoxic cell density) in an animal model with a clinical realistic image contrast.

  8. Impact of patient weight on tumor visibility based on human-shaped phantom simulation study in PET imaging system

    Musarudin, M.; Saripan, M. I.; Mashohor, S.; Saad, W. H. M.; Nordin, A. J.; Hashim, S.

    2015-10-01

    Energy window technique has been implemented in all positron emission tomography (PET) imaging protocol, with the aim to remove the unwanted low energy photons. Current practices in our institution however are performed by using default energy threshold level regardless of the weight of the patient. Phantom size, which represents the size of the patient's body, is the factor that determined the level of scatter fraction during PET imaging. Thus, the motivation of this study is to determine the optimum energy threshold level for different sizes of human-shaped phantom, to represent underweight, normal, overweight and obese patients. In this study, the scanner was modeled by using Monte Carlo code, version MCNP5. Five different sizes of elliptical-cylinder shaped of human-sized phantoms with diameter ranged from 15 to 30 cm were modeled. The tumor was modeled by a cylindrical line source filled with 1.02 MeV positron emitters at the center of the phantom. Various energy window widths, in the ranged of 10-50% were implemented to the data. In conclusion, the phantom mass volume did influence the scatter fraction within the volume. Bigger phantom caused more scattering events and thus led to coincidence counts lost. We evaluated the impact of phantom sizes on the sensitivity and visibility of the simulated models. Implementation of wider energy window improved the sensitivity of the system and retained the coincidence photons lost. Visibility of the tumor improved as an appropriate energy window implemented for the different sizes of phantom.

  9. Preoperative Prediction of Cervical Lymph Node Metastasis Using Primary Tumor SUVmax on 18F-FDG PET/CT in Patients with Papillary Thyroid Carcinoma

    Jung, Ji-hoon; Kim, Choon-Young; Son, Seung Hyun; Kim, Do-Hoon; Jeong, Shin Young; Lee, Sang-Woo; Lee, Jaetae; Ahn, Byeong-Cheol

    2015-01-01

    Objectives The aim of the current study was to evaluate the value of preoperative 18F-FDG (FDG) PET/CT in predicting cervical lymph node (LN) metastasis in patients with papillary thyroid carcinoma (PTC). Methods One hundred and ninety-three newly diagnosed PTC patients (M: F = 25:168, age = 46.8 ± 12.2) who had undergone pretreatment FDG PET/CT and had neck node dissection were included in this study. The FDG avidity of the primary tumor and the SUVmax of the primary tumor (pSUVmax) were ana...

  10. Correlation of FDG-PET measurements with morphometric tumor response after induction chemotherapy and adjuvant radiotherapy in stage III non-small cell lung cancer (NSCLC)

    Full text: Docetaxel (D) and carboplatin (C) combination chemotherapy (DC) has shown high response rates in advanced NSCLC. Histologic tumor response after chemotherapy or combined modality induction is strongly associated with systemic tumor control and potentially cure. Metabolic tumor response assessed by FDG-PET after induction chemotherapy with etoposide, ifosfamide and cisplatin (VIP) has been shown to be predictive of outcome in NSCLC. Finally, erythropoietin (EPO) may prevent the decrease in hemoglobin levels that was seen in a previous study of DC (median drop 2.7 g/dl) and thus may enhance treatment efficacy. The aim of the present study was to correlate FDG-PET studies with histomorphometric findings after DC induction chemotherapy plus Epo. 33 patients (pts) with NSCLC stage IIIA (7 pts) or IIIB (24 pts) were enrolled and received treatment with D 100 mg/m2 dl and C AUC 7.5 d2 q21 days for 4 cycles. Epo was given at 10,000 IU s.c. three times a week. All pts received adjuvant radiotherapy. Of 33 enrolled patients, 22 were evaluable for response by CT imaging. 14/22 pts (64 %) achieved PR. Of the 22 responders, 20 were evaluable for repeated FDG-PET studies. 13/20 pts had a decrease of standardized uptake values (SUV) and of the metabolic tumor index (MTI) by >50 %, 9/20 had SUV <2.5 (CR). Seven of these 9 pts underwent tumor resection, and specimens were subjected to morphometric analysis. In 7/7 cases, no vital tumor cells were detected in the specimens. In contrast to our previous study, hemoglobin levels increased by a median of 0.3 g/dl. Morphometric tumor response after induction chemotherapy correlates strongly with metabolic remission by FDG-PET. FDG-PET appears to be a useful non-invasive diagnostic tool to predict pathologic response and potentially long-term outcome in stage III NSCLC. (author)

  11. Usefulness of [18F]FDG-PET in diagnosis of gastric cancer, duodenal ampullary cancer and gastrointestinal storomal tumor (GIST). Study with multi-center survey by questionnaire

    [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) diagnosis of the three cancers in the title (gastric cancer (GC), duodenal ampullary cancer (DAC) and gastrointestinal storomal tumor (GIST), respectively) is not approved in the health insurance despite their high morbidity in Japan. Clinical usefulness and economical effectiveness in PET diagnosis of these cancers were studied by questionnaire to facilities, where PET had been conducted for the cancers in the period July, 2005-February, 2006. Major questions concerned the purpose and finding of PET, findings by other imaging and by tumor markers, and judgment of PET effectiveness compared with other imaging (more useful, equally or less, and its reason). Patients with GC were 173 cases (120 males, 53 females; mean age 65.3 y), with DAC, 10 (8, 2; 67.6 y), and with GIST, 15 (10, 5; 59.9 y). Obtained were the judgments in GC diagnosis of more useful in 47.4%, equally in 45.1% and less in 7.5%; in DAC, 20, 70 and 10%; and in GIST, 40, 46.7 and 13.3%, respectively. More useful was found in the primary lesion and useful, in the metastatic and recurrent lesions. FDG-PET could detect the latter lesions which had not been found by other imaging techniques, and such findings were thought to be also meaningful from the aspect of medical economics because of possible avoidance of inappropriate surgery and time reduction of hospitalization. (R.T.)

  12. Noninvasive Evaluation of Metabolic Tumor Volume in Lewis Lung Carcinoma Tumor-Bearing C57BL/6 Mice with Micro-PET and the Radiotracers 18F-Alfatide and 18F-FDG: A Comparative Analysis.

    Yu-Chun Wei

    Full Text Available To explore the value of a new simple lyophilized kit for labeling PRGD2 peptide (18F-ALF-NOTA-PRGD2, denoted as 18F-alfatide in the determination of metabolic tumor volume (MTV with micro-PET in lewis lung carcinoma (LLC tumor-bearing C57BL/6 mice verified by pathologic examination and compared with those using 18F-fluorodeoxyglucose (FDG PET.All LLC tumor-bearing C57BL/6 mice underwent two attenuation-corrected whole-body micro-PET scans with the radiotracers 18F-alfatide and 18F-FDG within two days. 18F-alfatide metabolic tumor volume (VRGD and 18F-FDG metabolic tumor volume (VFDG were manually delineated slice by slice on PET images. Pathologic tumor volume (VPath was measured in vitro after the xenografts were removed.A total of 37 mice with NSCLC xenografts were enrolled and 33 of them underwent 18F-alfatide PET, and 35 of them underwent 18F-FDG PET and all underwent pathological examination. The mean ± standard deviation of VPath, VRGD, and VFDG were 0.59±0.32 cm3 (range,0.13~1.64 cm3, 0.61±0.37 cm3 (range,0.15~1.86 cm3, and 1.24±0.53 cm3 (range,0.17~2.20 cm3, respectively. VPath vs. VRGD, VPath vs. VFDG, and VRGD vs. VFDG comparisons were t = -0.145, P = 0.885, t = -6.239, P<0.001, and t = -5.661, P<0.001, respectively. No significant difference was found between VPath and VRGD. VFDG was much larger than VRGD and VPath. VRGD seemed more approximate to the pathologic gross tumor volume. Furthermore, VPath was more strongly correlated with VRGD (R = 0.964,P<0.001 than with VFDG (R = 0.584,P<0.001.18F-alfatide PET provided a better estimation of gross tumor volume than 18F-FDG PET in LLC tumor-bearing C57BL/6 mice.

  13. Decision tree sensitivity analysis for cost-effectiveness of chest FDG-PET in patients with a pulmonary tumor (non-small cell carcinoma)

    Kosuda, Shigeru; Watanabe, Masumi; Kobayashi, Hideo; Kusano, Shoichi [National Defence Medical College, Tokorozawa, Saitama (Japan); Ichihara, Kiyoshi

    1998-07-01

    Decision tree analysis was used to assess cost-effectiveness of chest FDG-PET in patients with a pulmonary tumor (non-small cell carcinoma, {<=}Stage IIIB), based on the data of the current decision tree. Decision tree models were constructed with two competing strategies (CT alone and CT plus chest FDG-PET) in 1,000 patient population with 71.4% prevalence. Baselines of FDG-PET sensitivity and specificity on detection of lung cancer and lymph node metastasis, and mortality and life expectancy were available from references. Chest CT plus chest FDG-PET strategy increased a total cost by 10.5% when a chest FDG-PET study costs 0.1 million yen, since it increased the number of mediastinoscopy and curative thoracotomy despite reducing the number of bronchofiberscopy to half. However, the strategy resulted in a remarkable increase by 115 patients with curable thoracotomy and decrease by 51 patients with non-curable thoracotomy. In addition, an average life expectancy increased by 0.607 year/patient, which means increase in medical cost is approximately 218,080 yen/year/patient when a chest FDG-PET study costs 0.1 million yen. In conclusion, chest CT plus chest FDG-PET strategy might not be cost-effective in Japan, but we are convinced that the strategy is useful in cost-benefit analysis. (author)

  14. Decision tree sensitivity analysis for cost-effectiveness of chest FDG-PET in patients with a pulmonary tumor (non-small cell carcinoma)

    Decision tree analysis was used to assess cost-effectiveness of chest FDG-PET in patients with a pulmonary tumor (non-small cell carcinoma, ≤Stage IIIB), based on the data of the current decision tree. Decision tree models were constructed with two competing strategies (CT alone and CT plus chest FDG-PET) in 1,000 patient population with 71.4% prevalence. Baselines of FDG-PET sensitivity and specificity on detection of lung cancer and lymph node metastasis, and mortality and life expectancy were available from references. Chest CT plus chest FDG-PET strategy increased a total cost by 10.5% when a chest FDG-PET study costs 0.1 million yen, since it increased the number of mediastinoscopy and curative thoracotomy despite reducing the number of bronchofiberscopy to half. However, the strategy resulted in a remarkable increase by 115 patients with curable thoracotomy and decrease by 51 patients with non-curable thoracotomy. In addition, an average life expectancy increased by 0.607 year/patient, which means increase in medical cost is approximately 218,080 yen/year/patient when a chest FDG-PET study costs 0.1 million yen. In conclusion, chest CT plus chest FDG-PET strategy might not be cost-effective in Japan, but we are convinced that the strategy is useful in cost-benefit analysis. (author)

  15. Role of 18F- FDG PET-CT in detection of primary tumors in carcinoma of unknown primary site: an Indian experience

    Full text: The management of the patients with carcinoma of an unknown primary represents a difficult challenge in oncology. Metastatic cancers of unknown primary origin are characterised by a poor prognosis. Conventional radiological imaging allows only detection of 20%-27% of primary cancers. To evaluate the role of 18F-FDG PET/CT in detection of primary tumors in carcinoma of unknown primary site. Methods: In the present study, a total of 31 patients (22 males, 9 females; mean age 53.1 years) with biopsy or cytopathology proven metastatic carcinoma and negative conventional diagnostic procedures (CT, MRI or Panendoscopy) were included. All patients underwent whole body 18F-FDG PET/CT study. Patient data was retrospectively analysed. Histopathological diagnosis is kept as the gold standard. Hypermetabolic areas at the site of CT changes were considered as positive and rate of detection of primary site is evaluated. Among 31 patients, 18F-FDG PET/CT detected primary site in 14 patients. 18F-FDG PET/CT was negative in remaining 17 patients and could not localise primary. Among the 14 positive PET-CT patients, the results of 2 patients became false positive. The detection rate of 18F-FDG PET/CT in localising primary site was 38%. It is concluded that 18F-FDG PET/CT was found to be useful diagnostic procedure for the evaluation of patients with metastatic carcinoma and primary of unknown origin

  16. Preliminary assessment of dynamic contrast-enhanced CT implementation in pretreatment FDG-PET/CT for outcome prediction in head and neck tumors

    Abramyuk, Andrij; Wolf, Gunter; Tokalov, Sergey; Koch, Arne; Abolmaali, Nasreddin (OncoRay - Molecular and Biological Imaging, Medical Faculty Carl Gustav Carus, Dresden Univ. of Technology, Dresden (Germany)), e-mail: Andrij.Abramyuk@OncoRay.de; Shakirin, Georgy (Forschungszentrum Dresden Rossendorf, Inst. of Radiation Physics, Dresden (Germany)); Haberland, Ulrike (Siemens Healthcare Sector Computed Tomography, Forchheim (Germany)); Appold, Steffen (Clinic and Policlinic for Radiotherapy and Radiation Oncology, Univ. Clinics Carl Gustav Carus, Dresden Univ. of Technology, Dresden (Germany)); Zoephel, Klaus (Clinic and Policlinic for Nuclear Medicine, Univ. Clinics Carl Gustav Carus, Dresden Univ. of Technology, Dresden (Germany))

    2010-09-15

    Background: Recently published data show some controversy concerning the impact of [18F]-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in predicting head and neck tumors (HNT) outcome. Assessment of tumor blood supply parameters using dynamic contrast-enhanced CT (DCE-CT) may deliver additional information concerning this important question. Purpose: To evaluate the contribution of DCE-CT implemented in pretherapeutic FDG-PET/CT protocol for prognosis prediction in patients with HNT. Material and Methods: Ten consecutive patients (median age 50 years, range 47-74 years) with histologically proven HNT underwent FDG-PET/CT with DCE-CT before treatment. FDG uptake was measured by maximum standardized uptake value (SUVmax). Relative tumor blood volume (rTBV) was determined from DCE-CT using Patlak analysis. Intratumoral heterogeneity was assessed by means of lacunarity analysis. Obtained values were compared with time-to-progression and overall survival. PET and DCE-CT images were compared on a pixel-by-pixel basis using Pearson coefficient of correlation. Results: Three patients with lower FDG uptake (SUVmax: 8+-1) and five patients with higher FDG uptake (SUVmax: 15+-4, P=0.004) were free of local recurrence for 24 months. Two groups of patients with significantly differing lower (group A: 0.37+-0.02, n=6) and higher (group B: 0.52+-0.01, n=4; P<0.01), tumor heterogeneity (lacunarity) were identified. Corresponding mean rTBV was higher in group A (9.6+-1.8 ml/100 ml) than in group B (6.2+-0.6 ml/100 ml). All six patients with homogeneous tumor blood supply (lower lacunarity) and higher rTBV were free of local recurrence during 24 months, while two of four patients with heterogeneous tumor blood supply (higher lacunarity) and lower rTBV died during follow-up due to tumor relapse. A weak correlation between FDG-PET and DCE-CT rTBV was observed (R2=0.1). Conclusion: FDG-PET/CT and DCT-CT are complementary methods for surveillance

  17. Synthesis and In Vitro and In Vivo Evaluation of a New 68Ga-Semicarbazone Complex: Potential PET Radiopharmaceutical for Tumor Imaging

    N. S. Al-Hokbany

    2014-01-01

    Full Text Available In an attempt to develop new tumor imaging radiotracers with favorable biochemical properties, we have synthesized new 68Ga-2-acetylpyridine semicarbazone (68Ga-[APSC]2 as a potential positron emission tomography (PET tumor imaging agent using a straightforward and a one-step simple reaction. Radiochemical yield and purity were quantitative without HPLC purification. Biodistribution studies in nude mice model bearing human MDA-MB-231 cell line xenografts displayed significant tumor uptake of 68Ga-[APSC]2 radiotracer after 2 h postinjection (p.i.. The initial results demonstrate that 68Ga-[APSC]2 radiotracer may be useful probe for detecting and staging of hypoxic tumor using PET imaging modality.

  18. 18F-FDG and 18F-FLT-PET imaging for monitoring everolimus effect on tumor-growth in neuroendocrine tumors: studies in human tumor xenografts in mice.

    Camilla Bardram Johnbeck

    Full Text Available The mTOR inhibitor everolimus has shown promising results in some but not all neuroendocrine tumors. Therefore, early assessment of treatment response would be beneficial. In this study, we investigated the in vivo and in vitro treatment effect of everolimus in neuroendocrine tumors and evaluated the performance of 18F-FDG and the proliferation tracer 18F-FLT for treatment response assessment by PET imaging.The effect of everolimus on the human carcinoid cell line H727 was examined in vitro with the MTT assay and in vivo on H727 xenograft tumors. The mice were scanned at baseline with 18F-FDG or 18F-FLT and then treated with either placebo or everolimus (5 mg/kg daily for 10 days. PET/CT scans were repeated at day 1,3 and 10.Everolimus showed significant inhibition of H727 cell proliferation in vitro at concentrations above 1 nM. In vivo tumor volumes measured relative to baseline were significantly lower in the everolimus group compared to the control group at day 3 (126±6% vs. 152±6%; p = 0.016, day 7 (164±7% vs. 226±13%; p<0.001 and at day 10 (194±10% vs. 281±18%; p<0.001. Uptake of 18F-FDG and 18F-FLT showed little differences between control and treatment groups, but individual mean uptake of 18F-FDG at day 3 correlated with tumor growth day 10 (r2 = 0.45; P = 0.034, 18F-FLT mean uptake at day 1 correlated with tumor growth day 7 (r2 = 0.63; P = 0.019 and at day 3 18F-FLT correlated with tumor growth day 7 (r2 = 0.87; P<0.001 and day 10 (r2 = 0.58; P = 0.027.Everolimus was effective in vitro and in vivo in human xenografts lung carcinoid NETs and especially early 18F-FLT uptake predicted subsequent tumor growth. We suggest that 18F-FLT PET can be used for tailoring therapy for neuroendocrine tumor patients through early identification of responders and non-responders.

  19. The differentiation of malignant and benign musculoskeletal tumors by F-18 FDG PET/CT studies-determination of maxSUV by analysis of ROC curve

    Kong, Eun Jung; Cho, Ihn Ho; Chun, Kyung Ah; Won, Kyu Chang; Lee, Hyung Woo; Choi, Jun Heok; Shin, Duk Seop [Yeungnam University College of Medicine, Daegu (Korea, Republic of)

    2007-12-15

    We evaluated the standard uptake value (SUV) of F-18 FDG at PET/CT for differentiation of benign from malignant tumor in primary musculoskeletal tumors. Forty-six tumors (11 benign and 12 malignant soft tissue tumors, 9 benign and 14 malignant bone tumors) were examined with F-18 FDG PET/CT (Discovery ST, GE) prior to tissue diagnosis. The maxSUV(maximum value of SUV) were calculated and compared between benign and malignant lesions. The lesion analysis was based on the transverse whole body image. The maxSUV with cutoff of 4.1 was used in distinguishing benign from malignant soft tissue tumor and 3.05 was used in bone tumor by ROC curve. There was a statistically significant difference in maxSUV between benign (n = 11; maxSUV 3.4 {+-} 3.2) and malignant (n = 12; maxSUV 14.8 {+-} 12.2) lesion in soft tissue tumor ({rho} = 0.001). Between benign bone tumor (n = 9; maxSUV 5.4 {+-} 4.0) and malignant bone tumor (n = 14; maxSUV 7.3 {+-} 3.2), there was not a significant difference in maxSUV. The sensitivity and specificity for differentiating malignant from benign soft tissue tumor was 83% and 91%, respectively. There were four false positive malignant bone tumor cases to include fibrous dysplasia, Langerhans-cell histiocytosis (n = 2) and osteoid osteoma. Also, one false positive case of malignant soft tissue tumor was nodular fasciitis. The maxSUV was useful for differentiation of benign from malignant lesion in primary soft tissue tumors. In bone tumor, the low maxSUV correlated well with benign lesions but high maxSUV did not always mean malignancy.

  20. Combining [(11)C]-AnxA5 PET Imaging with Serum Biomarkers for Improved Detection in Live Mice of Modest Cell Death in Human Solid Tumor Xenografts

    Q. Cheng; Lu, L; Grafström, J; Olofsson, MH; Thorell, JO; Samén, E; K. Johansson; Ahlzén, HS; Stone-Elander, S; Linder, S; Arnér, Elias S.J.

    2012-01-01

    BACKGROUND: In vivo imaging using Annexin A5-based radioligands is a powerful technique for visualizing massive cell death, but has been less successful in monitoring the modest cell death typically seen in solid tumors after chemotherapy. Here we combined dynamic positron emission tomography (PET) imaging using Annexin A5 with a serum-based apoptosis marker, for improved sensitivity and specificity in assessment of chemotherapy-induced cell death in a solid tumor model. METHODOLOGY/...

  1. Bilateral pheochromocytomas and neuroendocrine tumor of pancreas demonstrated with FDG-PET/CT in a patient with von Hippel-Lindau syndrome: A case report

    Aim/Background: Von Hippel Lindau disease (VHL) is a hereditary cancer syndrome in which affected individuals are at risk for developing tumors in a number of organs, including the kidneys, brain, spine, adrenal glands, eyes and pancreas. Here we reported a case of a VHL syndrome with CNS hemangioblastoma, bilateral pheochromocytomas and pancreatic tumors and F-18 FDG PET/CT scan findings. Methods and Materials: A 21 year old female with no significant past medical or family history except iodine hypersensitivity (not suitable for CT contrast agents), presented initially with a CNS hemangioblastoma, which was completely resected. Her laboratory analysis showed increased 24-hour urine vanillylmandelic acid (VMA) and plasma metanephrine, and Ca19.9 levels. Other laboratory parameters were normal. She subsequently underwent a staging FDG PET/CT to exclude the possibility of other cancers of VHL syndrome. Whole-body image was obtained 60 minutes after the intravenous administration of 15 mCi of F-18 FDG on a Siemens Biograph 16 PET/CT scanner. Results: Whole body F-18 FDG PET/CT scan revealed an nonmetabolic area in the right cerebellar hemisphere secondary to tumor resection. Additionally, PET/CT study also showed abnormally increased FDG metabolism in the adrenal glands bilaterally and pancreas consistent with bilateral pheochromocytomas and pancreatic tumor. Bilateral pheochromocytomas and neuroendocrine tumor of pancreas were verified after surgical exploration. Discussions: VHL is a rare autosomal dominant familial cancer syndrome caused by germline deletions or mutations in the VHL tumor suppressor gene located on chromosome 3p25. Symptoms often begin in the second to third decades of life. Symptoms caused by VHL depend on the organ involved. Criteria for the diagnosis of VHL include: more than one hemangioblastoma in the CNS, one CNS hemangioblastoma and visceral manifestations of VHL, or one manifestation and a known family history of VHL. Important

  2. Evaluation of Clinical Contributions Provided by Addition of the Brain, Calvarium, and Scalp to the Limited Whole Body Imaging Area in FDG-PET/CT Tumor Imaging

    Bekir Tasdemir

    2014-01-01

    Full Text Available Purpose. The aim of this study was to detect additional findings in whole body FDG-PET/CT scan including the brain, calvarium, and scalp (compared to starting from the base of the skull in cancer patients and to determine contributions of these results to tumor staging and treatment protocols. Materials and Methods. We noted whether the findings related to the brain, calvarium, and scalp in 1359 patients had a potential to modify staging of the disease, chemotherapy protocol, radiotherapy protocol, and surgical management. We identified rates of metastatic findings on the brain, calvarium, and scalp according to the tumor types on FDG-PET/CT scanning. Results. We found FDG-PET/CT findings for malignancy above the base of the skull in 42 patients (3.1%, one of whom was a patient with an unknown primary tumor. Twenty-two of the metastatic findings were in the brain, 16 were in the calvarium, and two were in the scalp. Conclusion. This study has demonstrated that addition of the brain to the limited whole body FDG-PET/CT scanning may provide important contributions to the patient’s clinical management especially in patients with lung cancer, bladder cancer, malignant melanoma, breast cancer, stomach cancer, and unknown primary tumor.

  3. Staging of cervical cancer based on tumor heterogeneity characterized by texture features on 18F-FDG PET images

    The aim of the study is to assess the staging value of the tumor heterogeneity characterized by texture features and other commonly used semi-quantitative indices extracted from 18F-FDG PET images of cervical cancer (CC) patients. Forty-two patients suffering CC at different stages were enrolled in this study. Firstly, we proposed a new tumor segmentation method by combining the intensity and gradient field information in a level set framework. Secondly, fifty-four 3D texture features were studied besides of SUVs (SUVmax, SUVmean, SUVpeak) and metabolic tumor volume (MTV). Through correlation analysis, receiver-operating-characteristic (ROC) curves analysis, some independent indices showed statistically significant differences between the early stage (ES, stages I and II) and the advanced stage (AS, stages III and IV). Then the tumors represented by those independent indices could be automatically classified into ES and AS, and the most discriminative feature could be chosen. Finally, the robustness of the optimal index with respect to sampling schemes and the quality of the PET images were validated. Using the proposed segmentation method, the dice similarity coefficient and Hausdorff distance were 91.78   ±   1.66% and 7.94   ±   1.99 mm, respectively. According to the correlation analysis, all the fifty-eight indices could be divided into 20 groups. Six independent indices were selected for their highest areas under the ROC curves (AUROC), and showed significant differences between ES and AS (P  <  0.05). Through automatic classification with the support vector machine (SVM) Classifier, run percentage (RP) was the most discriminative index with the higher accuracy (88.10%) and larger AUROC (0.88). The Pearson correlation of RP under different sampling schemes is 0.9991   ±   0.0011. RP is a highly stable feature and well correlated with tumor stage in CC, which suggests it could differentiate ES and AS with high

  4. Automated contouring of tumor regions in treatment planning CT images using PET/CT images based on a localized level set method

    The aim of this study was to develop an automated method for contouring lung tumor regions in treatment planning computed tomography (CT) images using positron emission tomography (PET)/CT images. The initial regions of lung tumors were identified by thresholding the PET images at a certain percentage of maximum standardized uptake value (SUV). A localized level set method (LLSM), which we proposed in this study, was applied for the initial tumor region, and the proposed method determines an optimum contour of the gross tumor volume (GTV) region by searching a minimum point of average speed function on the contours of the LSM function with changing evolution time. For performance evaluation were employed the Dice similarity coefficient (DSC), which denotes the degree of a region similarity between the gold standard of the GTV determined by radiation oncologists and the GTV region obtained by our proposed method. We applied our proposed method to data sets of planning CT and PET/CT image sets for six lung cancer patients. The average DSC was 0.77, which seems to be feasible for segmentation of lung tumors. Preliminary results show that the proposed method may be useful for assisting treatment planners in delineation of the tumor region. (author)

  5. A prospective trial comparing FDG-PET/CT and CT to assess tumor response to cetuximab in patients with incurable squamous cell carcinoma of the head and neck

    Computed tomography (CT), the standard method to assess tumor response to cetuximab in incurable squamous cell carcinoma of the head and neck (SCCHN), performs poorly as judged by the disparity between high disease control rate (46%) and short time to progression (TTP) (70 days). F-18 fluorodeoxyglucose positron emission tomography (FDG-PET)/CT is an alternative method to assess tumor response. The primary objective of this prospective trial was to evaluate the metabolic response of target lesions, assessed as the change in maximum standardized uptake value (SUVmax) on FDG-PET/CT before and after 8 weeks (cycle 1) of cetuximab. Secondary objectives were to compare tumor response by CT (RECIST 1.0) and FDG-PET/CT (EORTC criteria) following cycle 1, and determine TTP with continued cetuximab administration in patients with disease control by CT after cycle 1 but stratified for disease control or progression by FDG-PET/CT. Among 27 patients, the mean percent change of SUVmax of target lesions after cycle 1 was −21% (range: +72% to −81%); by FDG-PET/CT, partial response (PR)/stable disease (SD) occurred in 15 patients (56%) and progression in 12 (44%), whereas by CT, PR/SD occurred in 20 (74%) and progression in 7 (26%). FDG-PET/CT and CT assessments were discordant in 14 patients (P = 0.0029) and had low agreement (κ = 0.30; 95% confidence interval [CI]: 0.12, 0.48). With disease control by CT after cycle 1, median TTP was 166 days (CI: 86, 217) if the FDG-PET/CT showed disease control and 105 days (CI: 66, 159) if the FDG-PET/CT showed progression (P < 0.0001). Median TTP of the seven patients whose post cycle 1 CT showed progression compared to the 12 whose FDG-PET/CT showed progression were similar (53 [CI: 49, 56] vs. 61 [CI: 50, 105] days, respectively). FDG-PET/CT may be better than CT in assessing benefit of cetuximab in incurable SCCHN

  6. Net-based data transfer and automatic image fusion of metabolic (PET) and morphologic (CT/MRI) images for radiosurgical planning of brain tumors

    Aim: The main purpose of radiosurgery in comparison to conventional radiotherapy of brain tumors is to reach a higher radiation dose in the tumor and sparing normal brain tissue as much as possible. To reach this aim it is crucial to define the target volume extremely accurately. For this purpose, MRI and CT examinations are used for radiotherapy planning. In certain cases, however, metabolic information obtained by positron emission tomography (PET) may be useful to achieve a higher therapeutic accuracy by sparing important brain structures. This can be the case, i.e. in low grade astrocytomas for exact delineation of vital tumor as well as in differentiating scaring tissue from tumor recurrence and edema after operation. For this purpose, radiolabeled aminoacid analogues (e.g. C-11 methionine) and recently O-2-[18F] Fluorethyl-L-Tyrosin (F-18 FET) have been introduced as PET tracers to detect the area of highest tumor metabolism which allows to obtain additional information as compared to FDG-PET that reflects the local glucose metabolism. In these cases, anatomical and metabolic data have to be combined with the technique of digital image fusion to exactly determine the target volume, the isodoses and the area where the highest dose has to be applied. Materials: We have set up a data transfer from the PET Center of the Zentralklinik Bad Berka with the Department of Stereotactic Radiation at the Helios Klinik Erfurt (distance approx. 25 km) to enable this kind of image fusion. PET data (ECAT EXACT 47, Siemens/CTI) are transferred to a workstation (NOVALIS) in the Dept. of Stereotactic Radiation to be co-registered with the CT or MRI data of the patient. All PET images are in DICOM format (obtained by using a HERMES computer, Nuclear Diagnostics, Sweden) and can easily be introduced into the NOVALIS workstation. The software uses the optimation of mutual information to achieve a good fusion quality. Sometimes manual corrections have to be performed to get an

  7. Evaluation of {sup 68}Ga-DOTA-TOC PET/CT for the detection of duodenopancreatic neuroendocrine tumors in patients with MEN1

    Morgat, Clement; Mazere, Joachim; Hindie, Elif; Fernandez, Philippe [CNRS, INCIA, Bordeaux (France); University of Bordeaux, INCIA, Bordeaux (France); University Hospital of Bordeaux, Department of Nuclear Medicine, Bordeaux (France); Velayoudom-Cephise, Fritz-Line; Nunes, Marie-Laure; Tabarin, Antoine [USN Haut-Leveque, Department of Endocrinology, Pessac (France); Schwartz, Paul; Guyot, Martine [University Hospital of Bordeaux, Department of Nuclear Medicine, Bordeaux (France); Gaye, Delphine [University Hospital of Bordeaux, Department of Radiology, Pessac (France); Vimont, Delphine; Schulz, Juergen [CNRS, INCIA, Bordeaux (France); University of Bordeaux, INCIA, Bordeaux (France); Smith, Denis [University Hospital of Bordeaux, Department of Oncology, Bordeaux (France)

    2016-07-15

    Somatostatin receptor scintigraphy with {sup 111}In-pentetreotide (SRS) is used to detect duodenopancreatic neuroendocrine tumors (dpNETs) in multiple endocrine neoplasia type 1 (MEN1). However, SRS has limited sensitivity for this purpose. Positron emission tomography/computed tomography (PET/CT) with {sup 68}Ga-DOTA-TOC has a higher rate of sporadic dpNETs detection than SRS but there is little data for dpNETs detection in MEN1. To compare the performances of {sup 68}Ga-DOTA-TOC PET/CT, SRS and contrast-enhanced computed tomography (CE-CT) to diagnose dpNETs in MEN1. Single-institution prospective comparative study Nineteen consecutive MEN1 patients (aged 47 ± 13 years) underwent {sup 68}Ga-DOTA-TOC PET/CT, SRS, and CE-CT within 2 months in random order. Blinded readings of images were performed separately by experienced physicians. Unblinded analysis of CE-CT, combined with additional magnetic resonance imaging, endoscopic-ultrasound, {sup 18}F-2-fluoro-deoxy-d-glucose ({sup 18}F-FDG) PET/CT or histopathology results served as reference standard for dpNETs diagnosis. The sensitivity of {sup 68}Ga-DOTA-TOC PET/CT, SRS, and CE-CT was 76, 20, and 60 %, respectively (p < 0.0001). All the true-positive lesions detected by SRS were also depicted on {sup 68}Ga-DOTA-TOC PET/CT. {sup 68}Ga-DOTA-TOC PET/CT detected lesions of smaller size than SRS (10.7 ± 7.6 and 15.2 ± 5.9 mm, respectively, p < 0.03). False negatives of {sup 68}Ga-DOTA-TOC PET/CT included small dpNETs (<10 mm) and {sup 18}F-FDG PET/CT positive aggressive dpNETs. No false positives were recorded. In addition, whole-body mapping with {sup 68}Ga-DOTA-TOC PET/CT identified extra-abdominal MEN1-related tumors including one neuroendocrine thymic carcinoma identified by the three imaging procedures, one bronchial carcinoid undetected by CE-CT and three meningiomas undetected by SRS. Owing to higher diagnostic performance, {sup 68}Ga-DOTA-TOC PET/CT (or alternative {sup 68}Ga-labeled somatostatin analogues

  8. Scintigraphy and PET scan in the exploration of the adrenal incidental tumor (incidentaloma)

    To eliminate a pheochromocytoma, the Mibg-scintigraphy has an excellent specificity and a sensitivity of 90%. The injuries do not fix this tracer and can get a PET scan with 18F-DOPA. Sometimes, a PET scan with 18F-F.D.G. can be useful even in absence of malignancy. To recognize an injury with a cortico-adrenal origin, the iodo-cholesterol is a specific tracer: in case of fixation of the tracer near the radiological injury, we can conclude generally to a benign cortico-adrenal injury. In case of lack of fixation of the tracer near the radiological injury, we will evoke a destructive injury of the adrenal gland, a priori malignant one. The PET scan with 18F-F.D.G. is also useful to help at the malignancy or not malignancy diagnosis of an adrenal mass whom radiological characteristics are not in favour of a typical adenoma. It is a whole body examination that allows to make an extension situation of a malignant adrenal mass in the same examination. (N.C.)

  9. Automatic FDG-PET-based tumor and metastatic lymph node segmentation in cervical cancer

    Arbonès, Dídac R.; Jensen, Henrik G.; Loft, Annika; Munck af Rosenschöld, Per; Hansen, Anders Elias; Igel, Christian; Darkner, Sune

    2014-03-01

    Treatment of cervical cancer, one of the three most commonly diagnosed cancers worldwide, often relies on delineations of the tumour and metastases based on PET imaging using the contrast agent 18F-Fluorodeoxyglucose (FDG). We present a robust automatic algorithm for segmenting the gross tumour volume (GTV) and metastatic lymph nodes in such images. As the cervix is located next to the bladder and FDG is washed out through the urine, the PET-positive GTV and the bladder cannot be easily separated. Our processing pipeline starts with a histogram-based region of interest detection followed by level set segmentation. After that, morphological image operations combined with clustering, region growing, and nearest neighbour labelling allow to remove the bladder and to identify the tumour and metastatic lymph nodes. The proposed method was applied to 125 patients and no failure could be detected by visual inspection. We compared our segmentations with results from manual delineations of corresponding MR and CT images, showing that the detected GTV lays at least 97.5% within the MR/CT delineations. We conclude that the algorithm has a very high potential for substituting the tedious manual delineation of PET positive areas.

  10. Role of {sup 18}F-FDG PET/CT in the evaluation of primary tumours of unknown origin; experience of the Hospital Angeles del Pedregal; Papel del 18F-FDG PET/CT en la evaluacion de tumores primarios de origen desconocido; experiencia del Hospital Angeles del Pedregal

    Sanchez, N.; Serna, J.A.; Quiroz, O.; Valenzuela, J.; Romo, C.; Ramirez, J.L. [Hospital Angeles del Pedregal, Mexico D.F. (Mexico)

    2007-07-01

    It was in 1994 when published studies appear that evaluate the utility of the {sup 18}F-FDG PET in the patients with primary tumors of unknown origin (TOD); starting from then diverse studies that support the clinical utility of the study arise with {sup 18}F-FDG PET in the detection of the primary tumor. It is as well as it has been calculated that the study with {sup 18}F-FDG PET is able to detect the primary tumor in around 40% of the patients with negative results in the conventional diagnostic procedures. Until the moment, most of the studies published in relation to the primary tumors of unknown origin only evaluate the paper of the study with {sup 18}F-FDG PET, without including the image fusion technique PET/CT, which has demonstrated in diverse studies; in oncological scenarios different from the TOD, a superior diagnosis certainty. (Author)