Publication Abstract

Authors: Huang XZ, Gao P, Song YX, Sun JX, Chen XW, Zhao JH, Ma B, Wang J, Wang ZN

Title: Impact of age on efficacy of postoperative oxaliplatin-based chemotherapy in patients with rectal cancer after neoadjuvant chemoradiotherapy.

Journal: Oncotarget 7(15):19643-53

Date: 2016 Apr 12

Abstract: BACKGROUND: Clinical practice guidelines focusing on age-related adjuvant chemotherapy for rectal cancer are currently limited. The present study aimed to explore the impact of age on the efficacy of adjuvant oxaliplatin-based chemotherapy in patients with rectal cancer after neoadjuvant chemoradiotherapy. METHODS: We performed a retrospective cohort analysis using data from the Surveillance, Epidemiology, and End Results-Medicare-linked database from 1992-2009. We enrolled patients with yp stages I-III rectal cancer who received neoadjuvant chemoradiotherapy and underwent curative resection. The age-related survival benefit of adding oxaliplatin to adjuvant 5-fluorouracil (5-FU) chemotherapy was evaluated using Kaplan-Meier survival analysis with propensity score-matching and Cox proportional hazards models. RESULTS: Comparing the oxaliplatin group with the 5-FU group, there were significant interactions between age and chemotherapy efficacy in terms of overall survival (OS) (p for interaction = 0.017) among patients with positive lymph nodes (ypN+). Adding oxaliplatin to 5-FU could prolong survival in patients aged < 73 years and ypN+ category, and but did not translate into survival benefits in patients aged ≥ 73 years and ypN+ category. No significant interactions were observed among ypN- patients, and oxaliplatin did not significantly improve OS, regardless of age. CONCLUSIONS: In patients with rectal cancer who have already received neoadjuvant chemoradiotherapy and undergone curative resection, adding oxaliplatin to 5-FU could prolong OS in patients aged < 73 years and ypN+ category. However, adding oxaliplatin did not translate into survival benefits in patients age ≥ 73 years and ypN+ category, or in ypN- patients.