Capecitabine and Oxaliplatin Before, During, and After Radiotherapy for High-Risk Rectal Cancer.

Purpose: To evaluate the effect of capecitabine and oxaliplatin before, during, and after radiotherapy for high-risk rectal cancer.

Patients And Methods: Patients with rectum cancer T4 or T3 involving the mesorectal fascia was included in a prospective phase 2 trial. Liver or lung metastases were accepted if the surgeons found them resectable. The patients received 6 weeks of capecitabine and oxaliplatin before chemoradiotherapy (CRT), continued capecitabine and oxaliplatin during radiotherapy, and received 4 weeks of capecitabine and oxaliplatin after CRT. The patients received radiotherapy as intensity-modulated radiotherapy. Total mesorectal excision was planned 8 weeks after CRT. The patients were evaluated with magnetic resonance imaging (MRI) before start of treatment, after 6 weeks of chemotherapy, and again just before the operation. The European Organization for Research and Treatment of Cancer (EORTC) QLQ-CR29 scoring system was used to evaluate adverse events.

Results: Fifty-two patients were enrolled between 2009 and 2012. The treatment was well tolerated, with only one death during treatment. Eighty percent of assessable patients experienced response to chemotherapy alone as evaluated by MRI, which increased to 94% after complete oncologic treatment. Forty-nine patients had a total mesorectal excision performed, all with a R0 resection and with a pathologic complete response of 20% for patients with T3 tumor and 7% for patients with T4 tumor. Five patients had metastases at study entry, while 47 patients had locally advanced rectal cancer without metastases. Of these 47 patients, overall survival and progression-free survival at 5 years was 72% and 62%, respectively, with a median follow-up of 60 months.

Conclusion: This aggressive approach with capecitabine and oxaliplatin before, during, and after radiotherapy for high-risk rectal cancer is safe and feasible; it also has an impressive response rate as measured by MRI and a promising 5-year overall survival.