RESUMO
AIM: The aim of this study was to investigate the significance of microscopic venous invasion (MVI) as a prognostic factor for patients with renal cell carcinoma (RCC). METHODS: The present study included 220 patients with non-metastatic RCC who underwent radical nephrectomy (RN). MVI was defined by the presence of a cancer cell in blood vessels based on microscopic examination of hematoxylin-eosin stained specimens. The impact of MVI on disease progression and survival after 37 (6-190) months of median follow-up and its correlation with known clinicopathological features were studied. Survival analyses using Kaplan-Meier and log-rank models for univariate comparisons and Cox proportional hazards model for multivariate analyses were performed. RESULTS: MVI was found in 68 patients (30.8%), and of these, 26 (38.2%) developed a tumor recurrence and 16 (23.5%) died of cancer progression, whereas only 18 (11.8%) of the remaining 152 patients without MVI presented with disease-recurrence and 8 (5.3%) died of cancer. In the multivariate analysis, MVI (P=0.014) Fuhrman's grade (P=0.028), and sarcomatoid differentiation (SD) (P=0.01) were the factors predicted a decreased disease-free survival (DFS). Meanwhile, MVI (P=0.04) and SD (P=0.029) were also found to be predictor of cancer specific survival (CSS) with necrosis (P=0.037) in multivariate analysis. CONCLUSION: The present study showed that MVI is associated with the vast majority of the adverse pathological features related with RCC. Furthermore, it was found to be an independent clinical prognostic factor for DFS and CSS.