[The prognosis of neck dissection with sternocleidomastoid muscle preservation and resection in advanced oral squamous cell carcinoma: a retrospective cohort analysis].

Purpose: To investigate the prognosis of advanced oral squamous cell carcinoma (AOSCC) patients undergoing neck dissection with sternocleidomastoid muscle (SCM) preservation and resection.
Methods: From January 2013 to June 2017, a total of 235 AOSCC patients(stage Ⅲ and stage Ⅳ) who were diagnosed and underwent neck dissection at the Department of Oral and Maxillofacial Surgery, College and Hospital of Stomatology, Guangxi Medical University, were collected and followed-up. The differences in overall survival（OS）, local recurrence-free survival (LRFS) and regional recurrence-free survival (RRFS) were compared between different surgical procedures. SPSS 25.0 software package was used for statistical analysis.
Results: Among 235 patients with postoperative follow-up, 101 patients retained the SCM during operation, and 134 patients had SCM removed. There was no significant difference in 5-year survival rate and 5-year regional recurrence rate between the SCM preservation group and the SCM resection group. Kaplan-Meier method of univariate analysis showed that SCM preservation or resection had no significant difference in OS, LRFS and RRFS. Cox multivariate regression analysis results showed that there was no significant difference between different surgical procedures in OS, LRFS and RRFS, while N stage and postoperative chemoradiotherapy were independent influencing factors for OS, LRFS and RRFS in AOSCC patients.
Conclusions: Neck dissection with SCM preservation in AOSCC patients has no effect on survival and recurrence (including local recurrence and regional recurrence). It is feasible for AOSCC patients to undergo SCM-preserving neck dissection when metastatic cervical lymph nodes do not invade SCM. N stage and postoperative chemoradiotherapy affect the prognosis of AOSCC patients.