Prognostic analysis and nomogram establishment in patients with head and neck myoepithelial carcinoma

Purpose To further explore the clinicopathological characteristics and determinants of survival of patients with HNMC. Methods The Surveillance, Epidemiology and End Results (SEER) database was used to collect the data of patients diagnosed with HNMC from 1975 to 2016. Kaplan-Meier analysis and log-rank testing compared the survival difference. Cox hazard regression models analyzed the survival outcome and prognostic factors. Concordance index (C-index) verified the nomogram. Results A total of 322 eligible cases were retrieved. The mean age at diagnosis was 61 years old and the male to female ratio was 1:1. The major salivary gland was the most common primary site (72.5%). Patients with adjuvant radiation showed better overall survival (OS) (P < 0.05). Advanced grade, N, M stage and nonsurgery contributed independently to shorter OS, while the advanced N, M stage and nonsurgery contributed independently to shorter disease-specific survival (DSS) (P < 0.05). The C-index of OS-specific nomogram was 0.768 (95% CI 0.726-0.810). Conclusions HNMC usually appears in elderly patients and has no gender difference. The 5-year OS and DSS rates are 70% and 79.8%, respectively. Grade, N, M stage and surgery are independent prognostic factors for OS, while N, M stage and surgery are independent prognostic factors for DSS. Compared with the surgery alone, adjuvant radiation appears to offer a significant OS benefit for patients with stage III or IV.