Quantitative tumour necrosis is an independent predictor of overall survival in clear cell renal cell carcinoma

Previous studies have reached conflicting results regarding whether tumour necrosis is a predictor of survival in clear cell renal cell carcinoma. In addition, studies quantifying the extent of necrosis are limited. The aim of this study was to determine if quantifying tumour necrosis could improve its predictive value for survival in clear cell renal cell carcinoma. We reviewed the clinical pathological information contained in The Cancer Genome Atlas for clear cell renal cell carcinoma and correlated it with overall survival using a Cox proportional hazard model. Necrosis was quantified on a single frozen section slide taken at the time of tissue harvesting for molecular studies. For all tumours, the presence of tumour necrosis was a significant predictor of overall survival (p < 0.001) on univariate analysis. When quantitated, >10% necrosis was associated with survival, but ≤10% necrosis was not. On multivariate analysis, age (p = 0.004), T3b stage (p = 0.02), M1 stage (p < 0.001), necrosis >30% (p < 0.001), and elevated serum calcium (p = 0.003) remained significant. For clinical stage 1-2 (T1-T2N0M0) tumours, necrosis >20% was significant on univariate analysis (p<0.005), and remained so on multivariate analysis (p < 0.001). We conclude that quantitating the extent of tumour necrosis adds prognostic information in clear cell renal cell carcinomas, including organ confined tumours.