Univariate analysis showed that male (hazard ratio (HR), 1,78; 95% CI, 1.02–3.11; P = 0.044), thickness >4.0 mm (HR, 2.45; 95% CI, 1.09–5.53; P = 0.031), lymph node metastasis (HR, 4.33; 95% CI, 2.39–7.86; P<0.001), AJCC stage III (HR, 6.25; 95% CI, 2.8–13.99; P<0.001) and IV (HR, 8.03; 95% CI 2.74–23.49; P<0.001), and IMP-3 (HR, 3.64; 95% CI, 1.55–8.58; P = 0.003) expression predicted an unfavorable OS (S1 Table). Here, IMP3 is linked to metastatic malignant neoplasm in the lymph nodes.