Postoperative hypofractionated–accelerated radiotherapy (HypoAR) for locally advanced rectal cancer

Abstract

Abstract Background despite the advances in preoperative hypofractionated–accelerated radiotherapy for patients with locally advanced rectal cancer, postoperative radiotherapy delivered with standard fractionation (46–50 Gy in 5 weeks) remains a standard adjuvant schedule. The role of hypofractionated–accelerated radiotherapy in a postoperative setting remains largely unexplored. Methods eighty-eight patients with rectal cancer infiltrating the rectal wall and/or having metastasis to the perirectal lymph nodes were treated with surgery followed by adjuvant chemotherapy and, subsequently, with hypofractionated–accelerated radiotherapy. Ten fractions of 3.4 Gy were delivered to the pelvis for 10 consecutive fractions, within 12 days. The follow-up of patients alive at the time of analysis ranges from 12–120 months (median 48). Results mild abdominal discomfort and diarrhoea were frequent, but medical medication was demanded in 14/88 (15.9%) of patients. The incidence of late toxicities was low; 4/88 (3.5%) patients complained for intermittent intestinal urgency. Locoregional recurrence occurred in 8/88 patients (9%). The 5-year locoregional relapse-free survival was achieved in 89.7% of patients, and this dropped to 84% in node-positive patients (P = 0.45). The 5-year disease-specific overall survival was 72.4%. Nodal involvement showed a trend to negatively affect prognosis (5-year overall survival 68.2 vs. 79.6%; P = 0.23). Conclusion postoperative hypofractionated–accelerated radiotherapy has minimal early and late toxicity. The locoregional control and disease-specific survival rates are similar to the expected from conventional postoperative chemoradiotherapy. The 2.5-fold decrease of radiotherapy treatment time, reduction of waiting lists and the lower overall cost of radiotherapy are additional benefits associated with hypofractionated–accelerated radiotherapy.