BIRC5 and esophageal squamous cell carcinoma: The combined OR was 1.92 (95% CI: 0.73–5.05; Z = 1.31; P = 0.39), 0.51 (95% CI: 0.14–1.87; Z = 1.01; P = 0.31), 1.05 (95% CI: 0.24–4.65; Z = 0.06; P = 0.95), 0.58 (95% CI: 0.16–2.08; Z = 0.84; P = 0.40) or 0.93 (95% CI: 0.41–2.15; Z = 0.16; P = 0.87), respectively, indicating that survivin expression in nuclei had no significant impact on the clinicopathological features of ESCC patients (Table 4).