Evaluation of purely accelerated six fractions per week radiotherapy in postoperative oral cavity squamous cell carcinoma.

Objectives: Randomized controlled trials have shown improved loco-regional control (LRC) and disease-free survival (DFS) by modest acceleration using six fractions per-week radiotherapy (RT) as compared to conventional fractionation in patients of head and neck squamous cell carcinoma. We aimed to evaluate the role of pure modestly accelerated fractionated radiotherapy (PM-ART) using six fractions per-week in patients of postoperative oral cavity squamous cell carcinoma (OCSCC).

Materials And Methods: Between May 2015 and July 2016, 40 OCSCC patients with ≥ 1 indication of RT were treated with adjuvant PM-ART, 60 Gray in 30 fractions over 5 weeks by three-dimensional conformal technique on a linear accelerator with a sixth 2 Gray fraction on Saturday using same fields. Primary endpoint was to assess acute toxicity, which was reviewed weekly during RT using Radiation Therapy Oncology Group criteria.

Results: Maximal grade 3 oral mucositis, pharynx/esophageal toxicity, and skin toxicity were seen in 77.5%, 25%, and 17.5%, respectively. Two patients had grade 4 mucositis. 47.5% were on tube feeding during RT. All the patients were taken off Ryle's tube within 4 weeks of RT completion. The median RT completion duration was 36 days. Three patients had treatment interruptions. With a median follow-up of 21.2 months, the 2-year LRC, DFS, and overall survival rates were 87.5%, 83.5%, and 85%, respectively. There were two distant failures.

Conclusion: PM-ART is feasible and tolerable. The high acute mucositis rates did not result in increased consequential late toxicity.