Two-week course of preoperative chemoradiotherapy followed by delayed surgery for rectal cancer: a phase II multi-institutional clinical trial (KROG 11-02)

Abstract

Purpose: The aim of this study was to evaluate the efficacy and safety of a two-week schedule of radiotherapy with oral capecitabine in locally advanced rectal cancer.

Methods and materials: Eighty patients with rectal cancer located in the mid to low rectum, staged cT3-4N0-2M0, were prospectively enrolled. They underwent preoperative chemoradiotherapy and delayed surgery 6-8 weeks after the completion of radiation therapy. A radiation dose of 33 Gy in 10 fractions was delivered to the pelvis for 2 weeks. One cycle of oral capecitabine was administered at a dose of 1650 mg/m(2)/day during radiotherapy. Tumor response and toxicity were the study endpoints. This study was registered at ClinicalTrials.gov (number, NCT01431599).

Results: All included patients underwent total mesorectal excisions including 12 cases of robot assisted surgery and 50 cases of laparoscopic surgery. Of the 80 patients, 27 (33.8%) achieved downstaging (ypT0-2N0) of a rectal tumor and 11 (13.8%) had a pathologically complete response (ypCR). Downstaging rates were 45% for T classification and 65% for N classification. Sphincter saving was achieved in 73 (91.3%) of the 80 patients. Of the 80 patients, 3 (3.8%) experienced grade 3 hematologic toxicity, and 2 (2.5%) had grade 3 postoperative complications such as ileus and wound dehiscence. There was no grade 4 toxicity.

Conclusion: A two-week schedule of radiotherapy with oral capecitabine in locally advanced rectal cancer patients showed low toxicity profiles and promising results in terms of tumor response.

Keywords: Preoperative chemoradiotherapy; Rectal cancer; Total mesorectal excision; Two-week course.