Clinical role of early dynamic FDG-PET/CT for the evaluation of renal cell carcinoma

ObjectivesWe studied the usefulness of early dynamic (ED) and whole-body (WB) FDG-PET/CT for the evaluation of renal cell carcinoma (RCC).MethodsOne hundred patients with 107 tumours underwent kidney ED and WB FDG-PET/CT. We visually and semiquantitatively evaluated the FDG accumulation in RCCs in the ED and WB phases, and compared the accumulation values with regard to histological type (clear cell carcinoma [CCC] vs. non-clear cell carcinoma [N-CCC]), the TNM stage (high stage [3–4] vs. low stage [1–2]), the Fuhrman grade (high grade [3–4] vs. low grade [1–2]) and presence versus absence of venous (V) and lymphatic (Ly) invasion.ResultsIn the ED phase, visual evaluation revealed no significant differences in FDG accumulation in terms of each item. However, the maximum standardized uptake value and tumour-to-normal tissue ratios were significantly higher in the CCCs compared to the N-CCCs (p < 0.001). In the WB phase, in contrast, significantly higher FDG accumulation (p < 0.001) was found in RCCs with a higher TNM stage, higher Furman grade, and the presence of V and Ly invasion in both the visual and the semiquantitative evaluations.ConclusionsED and WB FDG-PET/CT is a useful tool for the evaluation of RCCs.Key Points• ED and WB FDG-PET/ CT helps to assess patients with RCC• ED FDG-PET/CT enabled differentiation between CCC and N-CCC• FDG accumulation in the WB phase reflects tumour aggressiveness• Management of RCC is improved by ED and WB FDG-PET/CT