STAT3 and nonpapillary renal cell carcinoma: Our results demonstrate that pS727-STAT3 levels constitute an independent prognostic factor of overall survival that divides advanced-stage ccRCC patients into two groups: those with low pS727-STAT3 levels and better prognosis, and those with high pS727-STAT3 levels prone to die earlier over time (Fig. 2a,b).