Adjuvant chemotherapy in locally advanced rectal cancer after neo-adjuvant concurrent chemoradiotherapy and surgery: A retrospective study in Vietnamese patients

BACKGROUND: Advances in preoperative chemoradiotherapy and surgical techniques offered improvements in rates of locoregional recurrence but did not address distant metastasis. Traditionally, adjuvant chemotherapy has been administered with the goal of limiting systemic recurrences. OBJECTIVE: Evaluation of the efficacy and safety of adjuvant chemotherapy in patients with locally advanced rectal cancer after preoperative chemoradiotherapy and surgery. METHODS: From January 2017 to December 2018, 103 patients diagnosed with clinical stage II or III rectal cancer received adjuvant chemotherapy with capecitabine or XELOX regimens after neoadjuvant concurrent chemoradiotherapy and total mesorectal excision. Overall survival, disease-free survival, and toxicity were analyzed. RESULTS: The median follow-up time was 52.5 months (6.5–66.8 months). The mean 3-year disease-free survival and 3-year overall survival were 86.2% (95% CI: 82.8–89.6) and 92.2% (95% CI: 86.9–97.5), respectively. The rate of hematologic and nonhematologic toxicity was low, mostly grades 1 and 2 including anemia, leucopenia, thrombocytopenia, and liver enzymes elevations were 85.4, 50.5, 42.8, and 45.6%, respectively. CONCLUSION: The capecitabine and XELOX regimen in adjuvant settings for rectal cancer patients receiving neoadjuvant chemoradiotherapy and surgery was a safe and effective modality. Further randomized trials need to be conducted to evaluate the role of postoperative therapy for these individuals.