Risk factors for survival of head and neck soft tissue sarcomas: A comparison between 7th and 8th edition AJCC staging systems.

Abstract

Soft tissue sarcomas of the head and neck (HNSTS) show various histological types and clinical behaviour. Recently, the 8th edition of the American Joint Committee on Cancer (AJCC) proposed a staging system for HNSTS independent of other body soft tissue sarcomas, which requires validation. Therefore, we evaluated the prognostic factors for the survival of HNSTS patients through a comparison between previous and current AJCC staging systems. This study involved 135 consecutive HNSTS patients who underwent primary surgery, chemoradiotherapy or chemotherapy. Patients were grouped into staged (S) and not staged (NS) cancer according to the AJCC 8th edition staging. Cox proportional-hazard regression analyses were used to identify factors associated with overall survival (OS), and progression-free survival (PFS) in all, S or NS patients. Median follow-up period was 75months and the 5-year OS and PFS rates of all patients were 67.8% and 53.4%, respectively, which was similar between S and NS groups. Age, tumour size and grade, overall stage (7th edition) and resection margin were the significant prognostic factors for OS and PFS in all patients and NS group (all P<0.05), whereas positive resection margin was the only significant factor for OS and PFS in the S group (P<0.001). While OS was poorly discriminated among different 8th edition T-categories, different 7th edition showed good discrimination among overall stages in all patients and the NS group. The revised staging system may not provide an improved risk stratification for survival of HNSTS patients.