¹⁸F-FDG PET/CT predicts Fuhrman grade in renal clear cell carcinomas

Objectives To evaluate the usefulness of ¹⁸F-FDG PET/CT in the prediction of Fuhrman grade in renal clear cell carcinomas.

Methods 43 cases of pathologically confirmed renal clear cell carcinoma were retrospectively analyzed. The efficiencies of visual assessment, SUV_max, SUR_liver and SUR_aorta in differentiating high grade (Fuhrman III-IV) from low grade (Fuhrman I-II) were calculated and compared in pairs.

Results Among the 41 noncystic lesions included in the following analysis, 9 cases were diagnosed as PET positive, including 4 Fuhrman II cases, 4 Fuhrman III cases and one Fuhrman IV case. SUV_max, SUR_liver and SUR_aorta between low/high Fuhrman grade groups were statistically different. Between the two groups, SUV_max were 3.71±1.91,11.58±8.88 (t=-4.828,P<0.001),SUR_liver were 1.38±0.71,4.98±3.51 (t=-5.630,P<0.001),and SUR_aorta were 1.98±1.02,6.92±5.34 (t=-5.136,P<0.001). The AUCs of visual assessment, SUV_max, SUR_liver and SUR_aorta were 0.752,0.867,0.871 and 0.909, while their sensitivity and specificity were 62.50%,87.50%,87.50%,87.50% and 87.88%,84.85%,87.88%,87.88% respectively. The ROCs of SUR_aorta and visual assessment were statistically different (P = 0.0188), while those of other parameters were not.

Conclusions ¹⁸F-FDG PET/CT is useful in detecting high Fuhrman grade renal cell carcinomas, and SUR_aorta can be a promising parameter.