The Outcome of Induction Chemotherapy, Followed by Neoadjuvant Chemoradiotherapy and Surgery, in Locally Advanced Rectal Cancer.

Background & Objective: Currently, neoadjuvant chemoradiotherapy, followed by surgery, is the standard treatment for locally advanced rectal cancer. The use of induction chemotherapy for this tumor is controversial. In this study, the benefits and side effects of induction chemotherapy in locally advanced rectal cancer are evaluated.

Methods: Twenty-nine patients with locally advanced rectal cancer in 2018-2019 were enrolled in this study. Initially, they underwent induction chemotherapy (oxaliplatin 130 mg/m every 3 weeks and capecitabine 1000 mg/m twice a day for 14 days every 3 weeks for 2 courses). Then, neoadjuvant chemoradiotherapy (radiotherapy 50.4 Gy/28 for 5 days a week concomitant with weekly oxaliplatin 50 mg/m, as well as capecitabine 825 mg/m/bid on the days of radiotherapy) was administered. After 4 weeks, computed tomography (CT) scan of thorax, pelvis, and abdomen with and without contrast was performed. Total mesorectal surgery was performed 6-8 weeks after the end of radiotherapy. Four courses of adjuvant chemotherapy were applied. Pathologic complete response (pCR), margin, sphincter preservation, and adverse effects were assessed.

Results: In this study, pCR was present in 6 (20.7%) patients. R0 resection was done in 96.05%. Sphincter was preserved in 44.4% of lower rectal tumors. Two patients (6.9%) did not complete adjuvant treatment. Grade 3 adverse effects were documented in 13.7% of cases during induction chemotherapy and 17.2% of cases during neoadjuvant chemoradiation. Mortality was not reported.

Conclusion: Induction chemotherapy, followed by neoadjuvant chemoradiotherapy and surgery, would be an effective and safe modality in locally advanced rectal cancer.