Clinicopathologic features and prognostic factors in patients with renal cell carcinoma with sarcomatoid differentiation.

Renal cell carcinoma with sarcomatoid differentiation (RCCs) is rare, accounting for 1-8% of all RCC histological subtypes. In this study, we examined 139 patients with RCCs and aimed to explore their clinicopathologic features and prognostic factors. From January 2007 to January 2019, patients who were pathologically diagnosed with RCCs were included in this retrospective study. Data on clinicopathologic features and overall survival were collected. The expression of CK, vimentin, CK7, and CD10 in the sarcomatoid regions of RCCs was detected. The Kaplan-Meier curves and log-rank tests were used to describe the effect of clinicopathologic characteristics on overall survival. A Cox regression model was used to evaluate risk factors for prognosis. A total of 139 patients with RCCs were identified. The median age at diagnosis was 60 years. The median survival time of all patients was 39 months. The three- and five-year survival rates were 50.2% and 44.0%, respectively. A high pathologic T stage (pT3 and pT4), microvascular invasion, and lymph node metastasis were significant predictors of prognosis. Pathologic T4 stage and lymph node metastasis were independent prognostic factors for overall survival in patients with RCCs. Furthermore, the expression of CD10 was a prognostic factor for overall survival. In this study, a relatively large cohort of patients with RCCs was analyzed. We summarized the clinicopathologic features of RCCs and explored the risk factors for prognosis. Our findings may provide valuable prediction for clinical strategy.