BIRC5 and nasopharyngeal carcinoma: When the patient cohort was stratified according to tumor expression of both VEGF and survivin in 175 patients, The 5-year survival rate in 48 NPC patients with survivin and VEGF dual over-expression was significantly lower than that of 62 patients with dual low-expression (18.22% vs. 73.54%, respectively; P = 0.0003; Figure 5D).