Surgical treatment for locally advanced lower third rectal cancer after neoadjuvent chemoradiation with capecitabine: prospective phase II trial.

Background: Treatment of rectal cancer requires a multidisciplinary approach with standardized surgical, pathological and radiotherapeutic procedures. Sphincter preserving surgery for cancer of the lower rectum needs a long-course of neoadjuvant treatments to reduce tumor volume, to induce down-staging that increases circumferential resection margin, and to facilitate surgery.

Objective: To evaluate the rate of anal sphincter preservation in low lying, resectable, locally advanced rectal cancer and the resectability rate in unresectable cases after neoadjuvent chemoradiation by oral Capecitabine.

Methods: This trial included 43 patients with low lying (4-7 cm from anal verge) locally advanced rectal cancer, of which 33 were resectable. All patients received preoperative concurrent chemoradiation (45 Gy/25 fractions over 5 weeks with oral capecitabine 825 mg/m2 twice daily on radiotherapy days), followed after 4-6 weeks by total mesorectal excision technique.

Results: Preoperative chemoradiation resulted in a complete pathologic response in 4 patients (9.3%; 95% CI 3-23.1) and an overall downstaging in 32 patients (74.4%; 95% CI 58.5-85). Sphincter sparing surgical procedures were done in 20 out of 43 patients (46.5%; 95% CI 31.5-62.2). The majority (75%) were of clinical T3 disease. Toxicity was moderate and required no treatment interruption. Grade II anemia occurred in 4 patients (9.3%, 95% CI 3-23.1), leucopenia in 2 patients (4.7%, 95% CI 0.8-17) and radiation dermatitis in 4 patients (9.3%, 95% CI 3-23.1) respectively.

Conclusions: In patients with low lying, locally advanced rectal cancer, preoperative chemoradiation using oral capecitabine 825 mg/m2, twice a day on radiotherapy days, was tolerable and effective in downstaging and resulted in 46.5% anal sphincter preservation rate.