Preoperative chemoradiotherapy with capecitabine and oxaliplatin in patients with locally advanced rectal cancer.

Abstract

548 Background: Locally advanced rectal carcinoma is associated with high rate of abdomino-perineal amputation. We analyzed a cohort of patients (pts) diagnosed of locally advanced rectal cancer, treated with neoadjuvant chemoradiotherapy (QT-RT) with capecitabine and oxaliplatin (XELOX) followed by four cycles of adjuvant XELOX after surgery. Methods: Patients with locally advanced rectal cancer (T3-T4 and/or N+) were treated with oxaliplatin (50mg/m2 day 1, 8, 22 and 29) and capecitabine (1,650mg/m2 on days 1 to 14 and 22 to 35) combined with pelvic radiotherapy (180 cGy/day; 45Gy in 25 fractions). Surgery was scheduled 4 to 6 weeks after completion QT-RT. Four cycles of adjuvant XELOX were administered (capecitabine 2,000mg/m2 on days 1 to 14 and oxaliplatin 130mg/m2 on day 1) every 3 weeks. Main end points assessed were: rate of sphincter preservation, pathologic complete response (pCR) rate and the feasibility of postoperative chemotherapy. Results: From March 2007 to April 2010, 98 pts with locally advanced rectal cancer were included. M/F: 66/32; ECOG 0/1: 19/79; median age: 64 (38-81); upper/mid/distal rectum: 13/50/35; clinical stage: cT3/N- 9, cT2-T3/N+ 72, cT4/N- 4, cT4/N+ 13. Full dose of preoperative QT-RT was administered in 93 pts (95%). Main toxicities were grade 1/2 neurotoxicity (56/4) and grade 2/3 diarrhea (23/10). After treatment 96 pts underwent surgery. Sphincter preservation, R0 resections and pCR were achieved in 57, 93 pts and 17 (18%) patients, respectively, and 65 pts (66%) received all 4 cycles of adjuvant XELOX. Grade 3/4 toxicities included diarrhea 3/0, vomiting 2/0, neurotoxicity 5/0, hand-foot syndrome 1/0, neutropenia 4/0 and thrombopenia 0/4. 3-year progression-free and overall survival were 66% and 72%, respectively. No toxic deaths were reported. Downstaging in T/N stage was achieved in 53/71 pts (55/74%) respectively. Conclusions: Combination preoperative QT-RT with capecitabine and oxaliplatin is a well tolerated regimen and achieves encouraging rates of pCR, R0 resection, sphincter preservation and tumor downstaging in patients with locally advanced rectal cancer. No significant financial relationships to disclose.