Preoperative Treatment Combining Capecitabine with Radiation Therapy in Rectal Cancer: A GERCOR Phase II Study

Abstract

Objective(s): To assess efficacy and tolerability of preoperative capecitabine chemoradiation in rectal cancer. Methods: Patients received radiotherapy 45 Gy in 25 fractions over 5 weeks and capecitabine 825 mg/m² twice daily throughout radiotherapy. Surgery was performed 5–7 weeks after radiotherapy. The primary endpoint was pathological complete response, secondary endpoints were downstaging and tolerability. Results: Fifty-one patients were enrolled in a phase II study, median age 62 years (range 35–78). Sixty-three percent of tumours involved the lower third of the rectum, 45% were fixed. The median delivered radiotherapy dose was 44.8 Gy (range 39.6–45.0 Gy) over 33–49 days. The treatment-related grade 3 adverse events were diarrhoea (12%), skin reactions (8%) and asthenia (8%), with no grade 4 toxicity. Fifty patients underwent surgery (29 conservative) and 1 patient refused. The pathological complete response rate was 20% and a further 10% of patients had minimal residual disease. Additional tumour downstaging was seen in 28% of patients and the sphincter preservation rate was 58%. Conclusions: Preoperative capecitabine chemoradiation is well tolerated and its efficacy supports further exploration, both as a single agent and as part of new therapeutic strategies.