The Trends and Outcomes of Initial Palliative Chemotherapy in Patients with Pancreatic Cancer in Korea Based on National Health Insurance Service Data.

Background/Objectives: The survival rate of patients with pancreatic cancer (PC) has improved gradually since the introduction of FOLFIRINOX (FFX) and gemcitabine + albumin-bound paclitaxel (GnP) regimens. However, the trends and outcomes of initial palliative chemotherapy before and after the advent of these regimens and their contribution to survival rates are not well understood. This study aimed to investigate this in patients with PC in Korea using claims data from the National Health Insurance Service (NHIS). Methods: Patients diagnosed with PC who underwent initial palliative chemotherapy between 2007 and 2019 were identified from the NHIS database. Patient demographics, comorbidities, chemotherapy regimens, and survival rates were analyzed using follow-up data up to 2020. Results: In total, 14,760 patients (mean age, 63.78 ± 10.18 years; men, 59.19%) were enrolled. As initial palliative chemotherapy, 3823 patients (25.90%) received gemcitabine alone; 2779 (18.83%) received gemcitabine + erlotinib; 1948 (13.20%) received FFX; and 1767 (11.97%) received GnP. The median survival values were 15.00 months for FFX; 11.04 months for GnP; 8.40 months for gemcitabine alone; and 8.51 months for gemcitabine + erlotinib. The adjusted hazard ratio (aHR) for GnP vs. FFX was 1.291 (95% CI, 1.206-1.383) in the multivariate Cox regression analysis of mortality. Radiation therapy (aHR, 0.667; 95% CI, 0.612-0.728) and second-line chemotherapy (aHR, 0.639; 95% CI, 0.597-0.684) were significantly associated with improved survival. Conclusions: Our study found that first-line chemotherapy with FFX was associated with significantly longer survival than the other regimens, although caution is needed in interpreting the results.