Assessment of atherosclerosis in multiple myeloma and smoldering myeloma patients using 18F- sodium fluoride PET/CT.

BACKGROUND: To compare the NaF uptake in the thoracic aorta and whole heart, as an early indicator of atherosclerosis, in multiple myeloma (MM) and smoldering multiple myeloma (SMM) patients with a healthy control (HC) group. METHODS: Forty-four untreated myeloma patients (35 MM and nine SMM) and twenty-six age and gender-matched HC subjects were collected. Each individual's NaF uptake in three parts of the aorta (AA: ascending aorta, AR: aortic arch, DA: descending aorta) and the whole heart was segmented. Average global standardized uptake value means were derived by sum of the product of each slice area divided by the sum of those slice areas. Results were reported as target to background ratio (TBR). RESULTS: There was a significant difference between the NaF uptake in the thoracic aorta of myeloma and HC groups [AA (myeloma = 1.82 ± 0.21, HC = 1.24 ± 0.02), AR (myeloma = 1.71 ± 0.19, HC = 1.28 ± 0.03) and DA (myeloma = 1.96 ± 0.28, HC = 1.38 ± 0.03); P-values < 0.001]. The difference in the whole heart NaF uptake between two groups was also significant (P < 0.001). CONCLUSIONS: We observed a higher uptake of NaF in the thoracic aorta and whole heart of myeloma patients in comparison to the matched control group.

Prognostic significance of 18F-sodium fluoride in newly diagnosed multiple myeloma patients.

Focal bone lesions and fractures due to weakened bone are associated with higher morbidity and mortality of multiple myeloma (MM) patients. 18F-sodium fluoride (18F-NaF) is a sensitive PET radiotracer for detection of abnormal bone metabolism and, therefore, is particularly suited to assess the degree of bone involvement in MM patients. We aimed to investigate the prognostic significance of metabolic active volume (MAV) of 18F-NaF-avid lesions in MM patients. In addition to MAV, conventional methods of PET quantification, namely SUVmean and SUVmax, were measured in each patient for the purpose of comparison. Thirty-seven newly diagnosed MM patients were included. PET imaging was performed after intravenous administration of 200 MBq NaF. Active bone lesions and fractures on whole-body 18F-NaF-PET/CT scans were identified. An adaptive thresholding algorithm automatically calculated the total MAV, SUVmean and SUVmax for each patient (ROVER, ABX, Radeberg, Germany). The patients were followed for a median of 39.8 months after treatment (range: 17.8-55.4). The overall survival (OS) of patients with 18F-NaF-MAV value > 38.65 (36.36% [N of Events/Total N: 4/11]) was significantly shorter than that of patients with 18F-NaF-MAV value < 38.65 (3.85% [1/26]; P = 0.002). In multivariate forward stepwise (conditional LR) Cox regression analysis of prognostic factors of OS (including 18F-NaF-MAV (> 38.65 or < 38.65), age, gender, beta-2 microglobulin, and revised international staging system), 18F-NaF-MAV remained the only significant factor (HR: 14.39, P = 0.02). The results for PFS were not significant. Moreover, Kaplan-Meier analyses of conventional methods of PET quantification did not reveal any statistically significant log-rank p-values. MM patients with high 18F-NaF-MAV had shorter overall survival, compared to those with low 18F-NaF-MAV levels (NCT02187731).

Primary Synovial Sarcoma Presenting as a Huge Mass: A Report of a Rare Case and Review of Literature.

Primary synovial sarcoma of mediastinum is very rare among soft tissue sarcomas. Only a few cases have been reported in the literatures. The best treatment is still unclear, but, surgical resection is the main therapy. In this article we report a case of a 20*20 cm (2000gr) primary giant mediastinal synovial sarcoma in a 42 year-old man. We performed radical excision of the tumor and the metastasis.

Assessing the feasibility of NaF-PET/CT versus FDG-PET/CT to detect abdominal aortic calcification or inflammation in rheumatoid arthritis patients.

OBJECTIVE: We aimed to determine whether NaF-PET/CT or FDG-PET/CT can detect abdominal aortic molecular calcification and inflammation in patients with rheumatoid arthritis (RA). METHODS: In this study, 18 RA patients (4 women, 14 men; mean age 56.0 ± 11.7) and 18 healthy controls (4 women, 14 men; mean age 55.8 ± 11.9) were included. The controls were matched to patients by sex and age (± 4 years). All subjects of this study underwent NaF-PET/CT scanning 90 min following the administration of NaF. FDG-PET/CT imaging was performed 180 min following intravenous FDG injection. Using OsiriX software, the global mean standardized uptake value (global SUVmean) in abdominal aorta was calculated for both FDG and NaF. The NaF SUVmean and FDG SUVmean were divided by the blood pool activity providing target-to-background ratios (TBR) namely, NaF-TBRmean and FDG-TBRmean. The CT calcium volume score was obtained using a growing region algorithm based on Hounsfield units. RESULTS: The average NaF-TBRmean score among RA patients was significantly greater than that of healthy controls (median 1.61; IQR 1.49-1.88 and median 1.40; IQR 1.23-1.52, P = 0.002). The average CT calcium volume score among RA patients was also significantly greater than that of healthy controls (median 1.96 cm3; IQR 0.57-5.48 and median 0.004 cm3; IQR 0.04-0.05, P < 0.001). There was no significant difference between the average FDG-TBRmean scores in the RA patients when compared to healthy controls (median 1.29; IQR 1.13-1.52 and median 1.29; IQR 1.13-1.52, respectively, P = 0.98). CONCLUSION: Quantitative assessment with NaF-PET/CT identifies increased molecular calcification in the wall of the abdominal aorta among patients with RA as compared with healthy controls, while quantitative assessment with FDG-PET/CT did not identify a difference in aortic vessel wall FDG uptake between the RA and healthy control groups.

Association between age, uptake of 18F-fluorodeoxyglucose and of 18F-sodium fluoride, as cardiovascular risk factors in the abdominal aorta.

OBJECTIVE: We aimed to assess the feasibility of quantifying fluorine-18-fluorodexoglucose (18F-FDG) and 18F-sodium fluoride (18F-NaF) uptake in abdominal aorta and examine their association with age and cardiovascular risk factors. SUBJECTS AND METHODS: Our study comprised 123 subjects (48±14 years of age, 62 men) including 78 healthy volunteers and 45 patients with chest pain syndrome, who originally enrolled in the CAMONA study in Odense, Denmark (NCT01724749). All subjects underwent 18F-FDG positron emission tomography/computed tomography (PET/CT) and 18F-NaF PET/CT on separate days, 180min and 90min after administration of tracers, respectively. The global tracer uptake value (GTUV) in the abdominal aorta was determined as sum of the product of each slice area and its corresponding average standardized uptake value (SUV mean), divided by the sum of those slice areas. In addition, for each subject, the 10 years Framingham risk score (FRS) was calculated. The correlations between 18F-NaF and 18F-FDG GTUV with age and 10 years FRS were assessed in all, healthy and patient subjects. RESULTS: There was a significant, positive correlation between subjects' age and 18F-NaF GTUV (r=0.35, P<0.001), but not 18F-FDG GTUV (r=0.06, P=0.53). Also, there was a significant, positive correlation between 10 years FRS and 18F-NaF GTUV (r=0.30, P<0.001), but not 18F-FDG GTUV (r=0.01, P=0.95). Individual differences in 18F-FDG and 118F-NaF uptake were large in both healthy subjects and patients. CONCLUSION: In this study, the global uptake of 18F-NaF in abdominal aorta was positively associated with age and 10 years FRS in all subjects, healthy and patient groups, whereas the global uptake of 18F-FDG was not.