Adjuvant therapy for elderly patients with resected gastric adenocarcinoma: Population-based practices and treatment effectiveness

BACKGROUND: A study was undertaken to determine the survival benefit of postoperative chemoradiation therapy for elderly patients with resected gastric adenocarcinoma. METHODS: The authors identified 1023 individuals aged 65 years and older (median = 76) who underwent gastrectomy for nonmetastatic stage IB-IV gastric adenocarcinoma diagnosed between 2000 and 2002 in the linked Surveillance, Epidemiology, and End Results-Medicare database. They examined factors associated with receiving postoperative chemoradiation and analyzed the survival benefit associated with receiving postoperative chemoradiation. RESULTS: Thirty percent of patients received adjuvant chemoradiation. On multivariate analysis, younger age (P <.0001), lymph node involvement (P <.0001), and more recent diagnosis (P =.0284) were associated with receiving chemoradiation. There was a trend toward increased use among patients with less comorbidity (P =.0515). The median follow-up was 25.5 months, and 62% died. On multivariate survival analysis, older patients (P <.0001) and those with lymph node involvement (P <.0001), T3 or T4 disease (P =.0472), higher grade disease (P =.0355), and more comorbidity (P =.0411) were more likely to die. After adjustment for other factors, receipt of adjuvant chemoradiation therapy did not significantly increase survival (hazard ratio, 0.90; 95% confidence interval, 0.72-1.12; P =.3453) and did not increase survival in a multivariate analysis that included propensity scores (P =.2090). CONCLUSIONS: The authors did not detect a survival benefit, suggesting that some elderly patients with resected gastric adenocarcinoma may not gain a survival benefit from the administration of adjuvant chemoradiation. The analysis had limitations, and the results are hypothesis generating. Future gastric cancer trials should enroll more elderly patients and stratify patients by age to better understand the impact of treatment regimens on older patients.