Results from a prospective, randomised study on (accelerated) preoperative versus (conventional) postoperative radiotherapy in treatment of patients with resectable squamous cell carcinoma of the oral cavity – The ARTSCAN 2 study

Background and purpose An earlier prospective randomised multicentre study (ARTSCAN) in head and neck cancer patients that compared conventionally fractionated radiotherapy (CF) with accelerated radiotherapy (AF) was inconclusive. In the subgroup of oral cavity squamous cell cancer (OCSCC) a large absolute, but not statistically significant, difference in local control was seen in favour of AF. This difference was more pronounced in resectable tumours. The finding raised the hypothesis that AF could be beneficial for OCSCC patients. In addition, the longstanding controversy on pre- or postoperative radiotherapy was addressed. Materials and methods Patients with OCSCC, judged to withstand and likely benefit from combined therapy, were recruited. Subjects were randomised to either preoperative AF with 43 fractions given as a concomitant boost with two fractions/day to the tumour bearing volume to a total dose of 68 Gy in 4.5 weeks followed by surgery, or primary surgery with postoperative CF, total dose 60 or 66 Gy in 6-7 weeks. For patients whose tumours had high-risk features, 66 Gy and concomitant cisplatin was prescribed. Results 250 patients were randomised. Median follow-up was 5 years for locoregional control (LRC) and 9 years for overall survival (OS). There were no statistically significant differences between the two treatment arms regarding LRC and OS. LRC at five years was 73% (95% CI, 65-82) in preoperative AF and 78% (95% CI, 70-85) in postoperative CF. Toxicity was more pronounced in preoperative AF. Conclusion This study does not support that AF prior to surgery improves outcome in oral cavity cancer compared with postoperative CF.