Impact of dysplastic surgical margins for patients with oral squamous cell carcinoma

Objectives: Dysplastic changes at the surgical margin of oral squamous cell carcinoma (OSCC) could be encountered frequently. However, the impact of a dysplastic surgical margin on patients with OSCC remains unclear. Materials and methods: Retrospectively, we reviewed patients with OSCC who were diagnosed and treated at the National Taiwan University Hospital between January 2010 and December 2015. Patients were divided into four groups: clear ( >= 5 mm), close ( < 5 mm), positive, and dysplastic margins. Results: Of 1642 patients, 596 had clear margin, 169 had positive margin, 707 had close margin, and 170 had dysplastic margin. The mean age at diagnosis was 55 +/- 11 years (range, 16-97 years). Dysplastic margins were frequently present in patients with primary T1/T2 OSCC (odds ratio [OR] = 1.7, p = 0.009), tumor without perineural invasion (OR = 1.48, p = 0.04), and tumor thickness <= 10 mm (OR = 1.94, p = 0.001). In patients with clear, close, positive, and dysplastic margins, the 5-year disease-free survival rates were 63.1%, 51%, 37.2%, and 54.7%, respectively; overall survival (OS) rates were 71.1%, 61.9%, 49%, and 72%, respectively. Disease-free and overall survival were not significantly different in patients with dysplastic and clear margins (p = 0.37 and p = 0.38, respectively). Adjuvant radiotherapy had no significant benefit for patients with dysplastic margins. Finally, a multivariate analysis showed that the presence of a dysplastic margin was not an independent risk factor for disease-free (p = 0.43) and overall survival (p = 0.71). Conclusions: The survival rates of the patients with OSCC who had dysplastic margin were significantly better than those with positive margin.