Background and purpose: To study the effect of accelerated radiation treatment in locally advanced head and neck cancer, a prospective randomised trial was conducted comparing two fractionation schemes which differed only in the overall treatment time; fraction size and total dose were the same in both arms.
Materials and methods: Eighty-two patients with stage 3 or 4 squamous cell cancer of the oral cavity, oropharynx, hypopharynx or larynx considered suitable for radical radiotherapy as primary treatment were stratified by site and stage and randomised to receive 66 Gy in 33 2 Gy daily fractions in 45-48 days (o.d.) or 66 Gy in 33 2 Gy twice daily fractions in 22-25 days (b.i.d.).
Results: An initial improved clinical response in tumour control in the b.i.d. arm was not sustained and the 3 year recurrence free survival and overall survival rates were similar and not significantly different. The actuarial recurrence free survival was 49.1% in the b.i.d. arm and 44.3% in the o.d. arm. The disease free 3 year survival was 59.4% and 56.8%, respectively. The acute and late normal tissue effects were scored using the RTOG scale. As expected the acute effects were much greater in the b.i.d. arm. The combined grade 3 and 4 late effects were similar but the proportion of grade 4 reactions was significantly higher in the b.i.d. arm. The increase in grade 4 toxicity caused the trial to be discontinued after 82 of the planned 226 patients had been randomised.
Conclusions: The severity of the normal tissue effects and a failure to demonstrate sustained local control does not support this fractionation scheme in patients with such extensive head and neck cancer.