Surgical tumour margins and their significance in oral squamous cell carcinoma

There are many prognostic indicators used to predict tumour recurrence and overall prognosis in oral squamous cell carcinoma (OSCC). Most of these biological factors cannot be directly influenced by clinicians managing these heterogeneous group of tumours. Excision margins can potentially be increased at the time of surgery by including more normal tissue than the commonly accepted 1 cm resection distance from the macroscopic tumour edge. However, this can lead to poorer quality of life for patients and does not necessarily address microscopic extensions or dicohesive patterns of tumour growth. Surgical margins can be affected by tissue shrinkage immediately following resection and the choice of instrument used for surgery. Currently, most regard a clear resection margin as being >5 mm, a close margin as more than 1 mm but <5 mm and an involved margin <1 mm. In this article, we provide a brief overview of tumour margins in OSCC, including several recently published large meta-analyses. Based upon these and other studies, there is still conflicting data in the literature about the ideal margin for OSCC. There is a growing body of evidence that suggests a clearance of 1 mm might be adequate for some cancers. However, adequacy of resection should be considered along with the many other prognostic indicators of OSCC when the multi-disciplinary team considers further treatment for these patients.