Impact of dysplasia at resection margin on oncologic outcome after curative resection of oral tongue squamous cell carcinoma: significance of high-grade dysplastic resection margin.

ABSTRACT

BACKGROUND: This study aimed to compare the oncologic outcomes among negative, close, positive, and dysplasia resection margins (RMs) with oral tongue squamous cell carcinoma (OSCC) and to investigate the impact of dysplastic RMs. METHODS: The 565 patients were retrospectively analyzed and divided into four groups according to RM. Dysplasia was classified into mild, moderate, and severe subgroups. RESULTS: RMs consisted of negative (62.1%), close (27.1%), positive (2.1%), and dysplastic (8.7%). In multivariate analysis, advanced T/N stages and positive RM were significant risk factors for overall survival, while dysplasia at the RM was not a significant risk factor for locoregional recurrence or overall survival. In subgroup analysis of patients with dysplastic margin, RM with severe dysplasia showed higher recurrence than mild and moderate dysplasia. CONCLUSIONS: Dysplastic RM was not a risk factor for recurrence and survival. Severe dysplasia RM should be carefully observed due to higher recurrence compared to other dysplasia RMs.