Population-based outcomes research on treatment patterns and impact of chemotherapy in older patients with metastatic gastric cancer

Older patients with cancer are underrepresented in clinical trials, and thus, limited data are available on older patients with metastatic gastric cancer (MGC). This study was conducted to assess patterns of care, and outcomes of chemotherapy and its predictors, in older patients with MGC. Using the Korean Health Insurance Review and Assessment Service (HIRA) database, a nationwide population-based outcomes study was conducted. From the HIRA database, patients newly diagnosed with MGC in 2010 were identified (N = 1871). Patients aged a parts per thousand yen70 years were defined as older patients (N = 792) and those aged < 70 years as younger patients (N = 1079). Compared with younger patients, fewer older patients were diagnosed with MGC and received cancer treatment at high-volume medical institutions. Palliative chemotherapy was less frequently administered in older patients than in younger patients. In multivariate analyses, although combination chemotherapy as the first-line treatment (vs. monotherapy) and salvage chemotherapy after first-line chemotherapy (vs. no salvage chemotherapy) conferred more prolonged survival in the entire patient population, first-line combination chemotherapy did not provide an additional survival benefit in older patients compared to monotherapy. We found several barriers for older patients in approaching high-quality medical resources or receiving appropriate treatments. Although age was not an independent prognostic factor for survival in MGC, palliative chemotherapy was less frequently used in older patients. In our analysis, combination chemotherapy as the first-line treatment did not provide an additional benefit to older patients compared to monotherapy.