Transoral bisected resection for T1-2 oral tongue squamous cell carcinoma to secure adequate deep margin

Background: To investigate the clinical usefulness of transoral bisected resection (TBR) as a new method to secure adequate deep resection margin in T1-2 oral tongue squamous cell carcinomas (SCC). Methods: Among 75 patients with cT1-2N0 oral tongue SCCs, 45 (60%) received transoral en-bloc resection (TER) while 30 (40%) received patients underwent TBR. Primary tumor resection was performed with 1.5-cm surgical resection margin for both groups. Mucosal and deep resection margins, adjuvant treatments including re-resection of the tongue and cheomoradiotherapy, local and regional recurrence free survival, and overall survival were compared between the two groups. Results: Mean deep resection margin in the TBR group was 9.9 mm (95% CI: 8.4-11.4 mm), which was significantly (P < 0.001) wider than that of the TER group (mean: 5.4 mm, 95% CI: 4.5-6.3 mm). However, mucosal resection margins were not significantly (P=0.153) different between the two groups. Re-resection of tongue was performed for 6 (13.3%) of 17 (37.8%) patients with inadequate deep resection margin in the TER group and none (0%) in 4 (13.3%) patients with inadequate deep resection margin in the TBR group. Adjuvant radiation due to inadequate deep resection margin was performed for 6.7% of patients in both groups. The TBR group had better local recurrence free survival than the TER group. However, regional recurrence free survival and overall survival were not significantly different between the two groups. Conclusion: TBR could provide adequate deep resection margin for early stage tongue cancers with better local tumor control than TER. It can decrease the necessity of adjuvant treatment for re-resection of the tongue.