MUC3A and nonpapillary renal cell carcinoma: Furthermore, high MUC3A expression was found to be a identified negative prognostic factor for localized ccRCC patients in OS (HR, 2.509; 95 % CI, 1.136 to 5.539; P < 0.001) and RFS (HR, 2.658; 95 % CI, 1.287 to 5.489; P = 0.008).