Resection of early oral squamous cell carcinoma with positive or close margins: Relevance of adjuvant treatment in relation to local recurrence Margins of 3 mm as safe as 5 mm

The treatment strategy of early stage oral squamous cell carcinoma's (OSCC) resected with close or involved margins is a returning point of discussion. In this study we reviewed the consequences of re-resection (RR), postoperative radiotherapy (PORT) or watchful waiting (WW). Two-hundred patients with a primary resected Stage 1-2 OSCC of the tongue, floor of the mouth and cheek were included and retrospectively analysed. Local recurrence ratio was related to margin status, unfavourable histological parameters (spidery infiltrative, peri-neural and vascular-invasive growth) and postoperative treatment modality. 3-year overall survival (OS) and disease-specific survival (DSS) was calculated in relation to margin status. Twenty-two of 200 (11%) patients had pathological positive margins (PM), 126 (63%) close margins (CM), and 52 (26%) free margins (FM). OS and DSS were not significantly different between these groups. Nine of 200 (4.5%) patients developed local recurrent disease. Two (9.1%) had a PM, five (4.0%) a CM and two (3.8%) a FM. Of the nine recurrences, five patients had undergone PORT, one a RR, and three follow-up. Watchful waiting for CM ⩾3 mm with ⩽2 unfavourable histological parameters showed, besides margin status no significant differences with the FM group. With this treatment strategy, the local recurrence rate was 4.5%. No evidence was found for local adjuvant treatment in case of close margins ⩾3 mm with ⩽2 unfavourable histological parameters. Current data do not support the use of one treatment modality above any other.