Composition of Perinephric Fat and Fuhrman Grade in Clear Cell Renal Cell Carcinoma: The Role of Peritumoral Collateral Vessels

Background: The aim of this study was to investigate whether the presence of peritumoral collateral vessels could be indicative of a high Fuhrman grade (e.g., III and IV) in clear cell renal cell carcinoma (ccRCC). Methods: Between November 2019 and February 2020, a total of 267 ccRCC patients with histology-proven diagnoses were retrospectively analyzed and screened. Imaging analysis was performed on computed tomography (CT) images to assess the presence of peritumoral collateral vessels and understand the potential association with high Fuhrman grades. These vessels are defined as dilated and macroscopically visible peritumoral renal capsular veins. Results: A total of 190 ccRCC patients were included in the study, considering the exclusion criteria. In patients with peritumoral collateral vessels, there was a statistically significant greater presence of ccRCC with a high Fuhrman grade both among the total cohort of patients regardless gender (n = 190) (p < 0.001) as well as among ccRCC male patients only (n = 127) (p < 0.005). Conclusion: Here, we show a novel association between peritumoral collateral vessels and ccRCC with high Fuhrman grades in male patients. The presence of peritumoral collateral vessels in perinephric adipose tissue can be indicative of more aggressive ccRCC.