Effects of Chemotherapy on Survival Outcomes in Older Patients with Metastatic Pancreatic Cancer: A Nationwide Population-Based Study.

Clinical data on chemotherapy outcomes in older patients with pancreatic cancer are limited. This population-based study aimed to evaluate the effects of chemotherapy on survival outcomes in older patients with metastatic pancreatic cancer (mPC). Data from the National Health Insurance Service linked to the Korea Central Cancer Registry (2012 to 2019) were used. We assessed chemotherapy utilization and overall survival (OS) across various age groups and chemotherapy regimens. Among 20,549 patients with mPC, 8,652 received chemotherapy, including 711 and 163 patients aged 76-80 and ≥81 years, respectively. In the chemotherapy group, the median OS (mOS) was 9, 8, 7, and 6 months for the 21-70, 71-75, 76-80, and ≥81-year age groups, respectively (p<0.001). In contrast, untreated patients had an mOS of only 2 months across all age groups. Propensity score matching for patients aged ≥76 years revealed that chemotherapy was associated with a significantly longer mOS compared with no treatment (7 months vs 2 months: hazard ratio, 0.3; 95% confidence interval, 0.271 to 0.333; p<0.001). Among patients treated with gemcitabine plus nab-paclitaxel, the mOS was 11, 10, 9, and 7 months across the age groups, respectively (p<0.001). For those receiving the FOLFIRINOX regimen, the mOS was 12, 11, and 10 months in patients aged 21-70, 71-75, and 76-80 years, respectively (p=0.001). These real-world data suggest that chemotherapy is effective in older patients with mPC. Notably, chemotherapy with gemcitabine plus nab-paclitaxel and FOLFIRINOX provided substantial survival benefits even in patients aged 76-80 years, with only marginal differences compared to younger cohorts.