carbon-11-methionine and Multiple-Myeloma

A 68-year-old woman with a history of multiple myeloma on regular hematological follow-up and with no previous relevant gynecological diseases was found to have an incidental focal uptake by the right ovary at C-methionine PET/CT (C-MET). Transvaginal ultrasound was then performed showing a 2-cm solid right ovarian mass with irregular borders and moderate vascularization at color Doppler examination. Therefore, the patient underwent bilateral salpingectomy, and the final histological results revealed a rare presentation of mature teratoma with insular carcinoid tumor arising from the right ovary.

Topics: Aged; Carcinoid Tumor; Female; Humans; Incidental Findings; Methionine; Multiple Myeloma; Ovarian Neoplasms; Positron Emission Tomography Computed Tomography; Teratoma

to compare the results of tumor visualization when using 18F-FDG and 11C-methionine PET/CT after auto-HSCT in MM patients.. A prospective study included 27 MM patients subjected to 18F-FDG and 11C-methionine PET/CT on day 100 after auto-HSCT. Obtained images were visually and semi - quantitatively analyzed. Focal areas of increased uptake for every radiopharmaceutical agent (hypermetabolic foci) not associated with its physiological distribution were registered. Maximum Standardized Uptake Values (SUVmax) in pathological foci were automatically calculated for every radiopharmaceutical agent separately. PET/CT findings were compared to antitumor response achieved after auto-HSCT according to International MM Working Group criteria.. After auto-HSCT, the majority of patients (16/60%) achieved a complete response. Abnormal 18F-FDG uptake was registered in 37% (n=10) of patients, negative PET findings were obtained in 63% (n=17) of patients. 11C-methionine PET/CT revealed hypermetabolic foci in 67% (n=18) of patients, and there was no 11C-methionine uptake in 33% (n=9). Pathological foci of radiopharmaceutical agent uptake were 1.8 times more frequently revealed using PET/CT with 11C-methionine (p.. Цель исследования: сопоставить результаты визуализации опухолевого поражения методом позитронно - эмиссионной томографии, совмещенной с компьютерной томографией (ПЭТ/КТ) с 18F-фтордезоксиглюкозой (18F-ФДГ) и 11C-метионином у больных множественной миеломой (ММ) после трансплантации аутологичных гемопоэтических стволовых клеток (ауто-ТГСК). Материалы и методы. В проспективное исследование включено 27 больных ММ, которым на 100-й день после ауто-ТГСК выполнялась ПЭТ/КТ с 18F-ФДГ и 11C-метионином. Полученные изображения оценивали визуально и полуколичественно. Выявляли очаги повышенного накопления каждого из препаратов (очаги гиперметаболизма), не связанные с его физиологическим распределением. В патологическом очаге по каждому из препаратов в автоматическом режиме рассчитывалось максимальное стандартизированное значение накопления радиофармпрепаратов (SUVmax). Проводили сопоставление результатов ПЭТ/КТ и противоопухолевого ответа, достигнутого после ауто-ТГСК согласно критериям международной рабочей группы по изучению ММ. Результаты. После выполнения ауто-ТГСК у большинства больных (16/60%) достигнута полная ремиссия (ПР) заболевания. При использовании 18F-ФДГ патологическое накопление отмечено в 37% (n=10) случаев, ПЭТ-негативные результаты получены у 63% (n=17) больных. Очаги гиперметаболизма после применения 11C-метионина выявлены в 67% (n=18) случаев, отсутствие накопления определено у 33% (n=9) больных. При исследовании с 11C-метионином у больных ММ в 1,8 раза чаще определялись очаги патологического накопления радиофармпрепарата (p.

Topics: Carbon Radioisotopes; Fluorodeoxyglucose F18; Hematopoietic Stem Cell Transplantation; Humans; Methionine; Multiple Myeloma; Positron Emission Tomography Computed Tomography; Prospective Studies; Radiopharmaceuticals; Sensitivity and Specificity; Transplantation, Autologous

Multiple myeloma (MM) remains an essentially incurable hematologic malignancy originating from clonal plasma cells. This study evaluated the usefulness of the radiotracers (11)C-methionine (MET) and (18)F-2`-deoxy-2`-fluorodeoxyglucose (FDG) for staging and re-staging in MM. 43 patients with MM underwent both MET- and FDG-PET/CT for staging or re-staging within 3±2 days. Scans were compared on a patient and on a lesion basis. Tracer uptake was correlated with the degree of bone marrow (BM) involvement and standard clinical parameters of disease activity. Additionally, BM samples were stained for L-type amino acid transporter 1 (LAT1) expression in 15 patients. MET-PET detected focal lesions (FL) in 39/43 subjects (90.7%), whereas 10 patients were missed in FDG-PET/CT (detection rate, 33/43; 76.7%; p<0.05). MET depicted more FL in 28/43 patients (65.1%; p<0.001), whereas in the remainder (34.9%, n=15) both tracers yielded comparable results. LAT1 was highly expressed on the cell surface of myeloma cells. Both FDG and MET uptake correlated significantly with biopsy-proven BM involvement (p<0.001), with MET demonstrating a stronger correlation (SUVmean, r=0.9 vs r=0.6; SUVmax, r=0.88 vs r=0.58). Abnormal beta-2-microglobulin and free light chain levels correlated with the presence of focal intramedullary lesions detected in MET- or FDG-PET/CT (MET, p=0.006 and p=0.01, respectively; FDG, p=0.02 and p=0.01). MET appears to be superior to FDG for staging and re-staging of both intra- and extramedullary MM lesions. Tracer uptake correlates with BM involvement, β2m and FLC levels and appears to be a more accurate marker of tumor burden and disease activity.

Topics: Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Bone Marrow; Female; Fluorodeoxyglucose F18; Humans; Male; Methionine; Middle Aged; Multimodal Imaging; Multiple Myeloma; Positron-Emission Tomography; Radiopharmaceuticals; Tomography, X-Ray Computed

Multiple myeloma (MM) remains an essentially incurable hematologic malignancy. However, new treatment modalities and novel drugs have been introduced and thus additional tools for therapy monitoring are increasingly needed. Therefore, we evaluated the radiotracers 11C-Methionine (paraprotein-biosynthesis) and 18F-FDG (glucose-utilization) for monitoring response to anti-myeloma-therapy and outcome prediction. Influence of proteasome-inhibition on radiotracer-uptake of different MM cell-lines and patient-derived CD138+ plasma cells was analyzed and related to tumor-biology. Mice xenotransplanted with MM.1S tumors underwent MET- and FDG-μPET. Tumor-to-background ratios before and after 24 h, 8 and 15 days treatment with bortezomib were correlated to survival. Treatment reduced both MET and FDG uptake; changes in tracer-retention correlated with a switch from high to low CD138-expression. In xenotransplanted mice, MET-uptake significantly decreased by 30-79% as early as 24 h after bortezomib injection. No significant differences were detected thus early with FDG. This finding was confirmed in patient-derived MM cells. Importantly, early reduction of MET- but not FDG-uptake correlated with improved survival and reduced tumor burden in mice. Our results suggest that MET is superior to FDG in very early assessment of response to anti-myeloma-therapy. Early changes in MET-uptake have predictive potential regarding response and survival. MET-PET holds promise to individualize therapies in MM in future.

Topics: Animals; Cell Line, Tumor; Cell Proliferation; Humans; Methionine; Mice; Mice, Inbred NOD; Mice, SCID; Multiple Myeloma; Positron-Emission Tomography; Radiopharmaceuticals; Survival Analysis