Prospective phase II trial of neoadjuvant chemo-radiotherapy with Oxaliplatin and Capecitabine in locally advanced rectal cancer (XELOXART)

Neo-adjuvant chemo-radiotherapy (CT-RT) has been shown to decrease local recurrence rate in locally advanced rectal cancer. This multicenter phase II trial was conducted to evaluate the feasibility, safety and effectiveness of a combination of pre-operative radiotherapy and concurrent Capecitabine plus Oxaliplatin (XELOXART Trial). From October 2008 to May 2011, fifty consecutive patients affected with T3/T4 and/or N+ rectal cancer were enrolled. Treatment protocol consisted of 50.4 Gy in 28 fractions, Oxaliplatin 60 mg/m² once a week for 6 weeks and oral Capecitabine 825 mg/m² twice daily from day 1 to 14 and from day 22 to 35. Surgery was planned 6-8 weeks after. Main endpoints were pathological complete response rate (pCR) and the type of surgery performed compared to the planned one at diagnosis. 50 patients were included; pCR (ypT0N0M0) was achieved in 6 patients (12 %). Tumour downstaging was observed in 27 patients (54 %), and nodal downstaging in 32 patients (64 %). A total of 32 patients had lower rectal cancer, with 24 candidate for abdominal-perineal resection. At the end of CT-RT, a total of 12/24 (50 %) underwent conservative surgery. Grade 3 toxicity (fatigue and diarrhoea) occurred in 4 % of patients; grade 4 sensory neuropathy occurred in 2 % of patients. Perioperative complications of any grade occurred in 10 % of patients. Pre-operative CT-RT with Capecitabine-Oxaliplatin was well tolerated and resulted in an encouraging sphincter preservation and tumour downstaging rate. No improvements in terms of pathological complete response rate were shown.