Impact of renal vein invasion and fat invasion in pT3a renal cell carcinoma.

Abstract

• To evaluate the prognostic impact of tumor fat invasion (FI) and renal vein invasion (RVI) in patients with T3a renal cell carcinoma. • In total, 220 consecutive patients treated for renal cell carcinoma between 1992 and 2009 were analyzed. T3a stage cases were selected. • A single pathologist reviewed all cases. • The present study cohort included 46 patients with mean follow-up of 28.6 months, of whom 17 (36.9%) died from disease. Patients were initially divided into three groups including 24 (52.1%) of FI only, 11 (23.9%) of RVI only and 11 (23.9%) of both FI and RVI. • In univariate analysis, no significant differences in disease-specific survival (DSS) were noted between FI only and RVI only groups (P= 0.91). DSS was significantly worse in the FI + RVI group compared to the other groups (P= 0.02). • When grouped into FI or RVI vs FI + RVI, DSS remained significantly lower in the group containing the parameters concurrently (P= 0.009). Progression-free survival also was significantly lower in FI + RVI group (P= 0.01). • Metastasis, positive lymph nodes and the presence of FI + RVI remained as isolated predictors of survival. • Patients with FI + RVI presented a 2.6-fold increase in risk of death from cancer and a 2.5-fold increase in risk of disease progression (P= 0.04) compared to those with either of them alone. • The isolated or concomitant presence of FI and RVI may be used as one of the criteria for staging in the next edition of the Tumour-Node-Metastasis classification because they have significantly different outcomes.