BRCC3 and nasopharyngeal carcinoma: Multivariate analysis including the BRCC3 expression level, T classification, N classification, distant metastasis and skull-base invasion demonstrated that the BRCC3 expression level (P = 0.01), distant metastasis (P < 0.001), relapse (P = 0.001), and skull-base invasion (P = 0.013) were independent prognostic factors for NPC (Table 2).