Contact with renal sinus is associated with poor prognosis in surgically treated pT1 clear cell renal cell carcinoma

OBJECTIVE To investigate the prognostic significance of contact with the renal sinus in patients with clear cell renal cell carcinoma. METHODS A total of 787 pT1N0M0 clear cell renal cell carcinoma patients who had undergone radical or partial nephrectomy were reviewed retrospectively. A tumor in contact with the renal sinus was defined as a tumor radiologically attached to the renal sinus. Metastatic-free survival rates were analyzed in the total and propensity score-matched cohorts. A risk score model for metastasis after surgery was developed. RESULTS Of the 787 patients, 411 (52.2%) had tumors in contact with renal sinus. The contact with renal sinus group showed poorer metastatic-free survival in both total and matched cohorts. In multivariate analysis, contact with renal sinus was an independent prognostic factor of metastasis, as well as Fuhrman grade, microvascular invasion and age. The scoring model likewise consisted of Fuhrman grade, microvascular invasion, age and contact with renal sinus. Metastasis-free survival curves were clearly stratified according to risk, with 5-year metastasis-free survival rates of 95.7% and 65.2% in the low- and high-risk groups, respectively (P