Lymphovascular invasion in clear cell renal cell carcinoma-Association with disease-free and cancer-specific survival

ObjectivesThe objective is to evaluate the effect of lymphovascular invasion (LVI) on disease-free survival (DFS) and cancer-specific survival (CSS) in patients with clinically localized clear cell renal cell carcinoma (ccRCC).MethodsPatients with ccRCC who were treated surgically in 1997 to 2010 were identified. Retrospective chart review was performed to identify clinical outcomes. Independent pathologic re-review was performed by a single pathologist to confirm LVI status. Pathologic features were correlated with clinical outcomes using Kaplan-Meier and Cox regression analyses.ResultsFour hundred and nineteen patients with nonmetastatic ccRCC comprised the study cohort. Three hundred and thirty-three of these patients had an organ-confined (pT1-2, N any, and M0) disease. LVI was present in 14.3% of all nonmetastatic patients. In all patients with nonmetastatic ccRCC, presence of LVI was correlated with significantly shorter DFS (P <0.001) and CSS (P = 0.001) on Kaplan-Meier analysis. In cases of organ-confined, nonmetastatic ccRCC, presence of LVI was a significant predictor of DFS (hazard ratio = 4.0, P = 0.026) and CSS (hazard ratio = 12.7, P = 0.01) on multivariate analysis. Patients with organ-confined RCC who were LVI positive had similar DFS (P = 0.957) and CSS (P = 0.799) to patients with locally advanced tumors (pT3-pT4, N any, and M0) on Kaplan-Meier analysis.ConclusionsThe presence of LVI is an independent predictor of both DFS and CSS in organ-confined, nonmetastatic ccRCC. LVI positivity in patients with otherwise pathologically organ-confined ccRCC confers oncologic outcomes similar to those of patients with locally advanced disease. If confirmed by others, future revisions to the tumor-node-metastasis staging system may incorporate LVI status into the prognostic algorithm of patients with RCC.