PT - JOURNAL ARTICLE AU - Furuya, Sho AU - Manabe, Osamu AU - Ohira, Hiroshi AU - Naya, Masanao AU - Hirata, Kenji AU - Koyanagawa, Kazuhiro AU - Aikawa, Tadao AU - tsujino, Ichizo AU - Oyama-Manabe, Noriko AU - Shiga, Tohru TI - <strong>FMISO PET/CT detects hypoxia lesions in cardiac and extra-cardiac sarcoidosis.</strong> DP - 2019 May 01 TA - Journal of Nuclear Medicine PG - 379--379 VI - 60 IP - supplement 1 4099 - http://jnm.snmjournals.org/content/60/supplement_1/379.short 4100 - http://jnm.snmjournals.org/content/60/supplement_1/379.full SO - J Nucl Med2019 May 01; 60 AB - 379Objectives: 18F-fluorodeoxyglucose (FDG) PET plays an important role in diagnosis of cardiac sarcoidosis (CS). However, both long-period of fasting and special dietary instructions are required to suppress the physiological myocardial FDG uptake. We previously reported a case with 18F-fluoromisonidazole (FMISO) accumulation in CS. However, the relationship between FMISO and FDG accumulations is not well investigated. The aims of this prospective study were 1) to assess whether physiological FMISO uptake in the myocardium is seen or not 2) to compare the FMISO and FDG uptakes in patients with sarcoidosis. Materials and Methods: Eight patients who were diagnosed as sarcoidosis were enrolled in this study. All patients underwent FMISO PET and FDG PET within 10 days (median: 6 days, range: 1-7 days). All patients fasted overnight (for at least 18 hours) preceded by a low-carbohydrate diet before FDG PET but were given no special dietary preparations before FMISO PET. CS was diagnosed based on Japanese Society of Sarcoidosis and Other Granulomatous disorders 2015 guideline. FMISO and FDG uptake of cardiac and extra-cardiac involvement was evaluated visually and semi-quantitatively using maximum standardized uptake value (SUVmax). The degree of radiotracer uptake in the sarcoidosis lesions was visually classified as negative or positive compared with the blood pool uptake. For sarcoidosis lesions not visible on FMISO PET scan, a region of interest (ROI) was drawn corresponding to the FDG images. The metabolic volume was defined as the volume within the boundary determined using the threshold as the SUVmean of the blood pool × 1.5. Results: Seven (88%) patients were diagnosed as CS. Six patients showed both cardiac and extra-cardiac FDG uptake due to the sarcoidosis. One patient had only cardiac involvement, 1 patient had extra-cardiac FDG uptake but not cardiac lesion. FDG scans were performed at 1 hour after tracer injection and FMISO scans were performed at 4 hours after injection. All CS patients showed focal FDG uptake pattern without physiological myocardial uptake. No patient showed the physiological uptake of FMISO. FMISO uptake was observed in five CS patients (5/7). In the semiquantitative assessment of FDG PET, the mean ± standard deviation (SD) of SUVmax was 8.18 ± 1.71 for the cardiac lesion. This result was significantly higher than that of FMISO PET (2.43 ± 0.59; p &lt; 0.0001). The uptake of cardiac lesion did not have a significant correlation between FDG and FMISO (R = 0.022, p = 0.75). Eight extra-cardiac sarcoidosis involvements (6 mediastinal/hilar lymph nodes and 2 lungs) were found in FDG PET. FMISO PET detected 4 lesions (3 mediastinal/hilar lymph nodes and 1 lung). There was no lesion that FMISO uptake showed positive but FDG uptake did not. SUVmax of FDG PET was 11.6 ± 5.93 which was significantly higher than that of FMISO PET (2.41 ± 1.25; p &lt; 0.0001). Extra-cardiac lesion did not have a significant correlation between FDG and FMISO uptake (R = 0.35, p = 0.12). The extra-cardiac lesion with FMISO uptake had higher metabolic volume of FDG PET compared to the lesion without FMISO PET (125.3 ± 82.2 vs 13.9 ± 13.4 ml; p = 0.037). Conclusions: No patient showed the physiological uptake of FMISO even without special dietary preparations. This preliminary study demonstrated that hypoxia exists independently of FDG uptake in CS. FMISO PET may provide the alternative information in CS even without special dietary preparations.