Trophoblast Cell Surface Antigen 2 (Trop2) in Chromophobe Renal Cell Carcinoma

Background: Overexpression of tumor-associated calcium signal transducer 2 (Trop2) is found in many tumor entities. The prognostic value of Trop2 in renal cell renal carcinoma (RCC), especially in nonclear cell RCC, is still unclear. Aim: The aim of this study was to evaluate the prognostic impact of Trop2 expression in a large cohort of patients with chromophobe (ch)RCC. Materials and Methods: Patients who underwent renal surgery due to chRCC were retrospectively evaluated. Tumor specimens were analyzed for Trop2 expression by immunohistochemistry. Results: Eighty-one chRCC patients were eligible for analysis, of these 24 (29.6%) patients were positive for Trop2. No significant associations were found for Trop2 expression and clinical attributes in patients with chRCC. The Kaplan-Meier analysis revealed no differences in 5-year overall survival for Trop2- compared to Trop2+ (89.6% vs. 100.0%; p = 0.288). Conclusion: In chRCC, Trop2 expression is not associated with survival and other parameters of aggressiveness. Due to the rare incidence of chRCC, further studies with larger cohorts are warranted.