Mark W. Ball et al. from the James Buchanan Brady Institute of Urology at Johns Hopkins University School of Medicine published an article in the 2015 issue of BJU Int on the extent of renal vein invasion affecting the prognosis of patients with renal cell carcinoma, primarily to compare segmental versus main renal vein invasion (RVI) in patients with renal cancer on patient prognosis The impact of RVI on patient prognosis. The study retrospectively analyzed kidney cancer patients who underwent resection from 2003 to 2013 and were divided into five groups: T2 (N = 135), T3a with fatty infiltration (N = 185), T3a with segmental renal vein invasion (N = 87), T3a with main renal vein invasion (N = 64), and T3b (N = 40). Kaplan-Meier survival analysis and multivariate Cox regression analysis were used to determine the effect of segmental renal vein invasion on recurrence-free survival (RFS) and tumor-specific survival (CSS). The Haller C index was used to compare the prognostic accuracy of current and recommended staging models. RESULTS: At a median follow-up of 37 months, RFS and CSS were significantly worse in patients with main renal vein invasion compared with segmental renal vein invasion (P values 0.03 and 0.009, respectively). In multivariate Cox regression analysis, the risk of recurrence was significantly higher (HR 2.3, 95% confidence interval: 1.1-4.4, P = 0.03) and CSS was significantly lower (HR 3.5, 95% confidence interval 1.3-9.9, P = 0.02) in main renal vein invasion compared with segmental deep vein invasion. The accuracy of prognostic judgments was improved in subgroup T3a by differentiating between segmental and main renal vein invasion compared with the current staging system for CSS (C index 0.66 vs. 0.59) and RFS (0.70 vs. 0.60). Thus, main renal vein invasion was associated with having poorer RFS and CSS compared to segmental renal vein invasion.The results of this study may be instructive for patient counseling and future staging guidelines.