STAT3 and nasopharyngeal carcinoma: Multivariate Cox regression analysis revealed that T stage, LNM, N stage, clinical stage and expression of JAK2, STAT3 and VEGF were independent risk factors associated with the prognosis of NPC patients (all P < 0.05), while the factors of gender, age, differentiation type, smoking and family history had no effect on the prognosis of patients with NPC (all P < 0.05) (Table 4).