Comparison of the Efficacy of Nal-IRI+5FU/LV and S-1 in Patients with Advanced Pancreatic Cancer Refractory to Gemcitabine and Nab-Paclitaxel.

INTRODUCTION

Nanoliposomal irinotecan (nal-IRI) + 5-fluorouracil (FU)/leucovorin (LV) is the new standard second-line therapy for advanced pancreatic cancer (PC). Tegafur, gimeracil, and oteracil potassium (S-1) have been used in advanced PC after gemcitabine (GEM) plus nab-paclitaxel treatment, but the clinical difference between nal-IRI+5-FU/LV and S-1 remains unclear.

METHODS

We retrospectively compared the efficacy and safety of nal-IRI+5-FU/LV and S-1 in patients with advanced PC refractory to GEM plus nab-paclitaxel. The primary endpoints were progression-free survival (PFS) and overall survival (OS). Secondary endpoints included objective response rate (ORR), disease control rate (DCR), and safety.

RESULTS

We analyzed patients with advanced PC who were refractory to GEM plus nab-paclitaxel from May 2015 to January 2022 at our hospital. Twelve patients treated with nal-IRI+5-FU/LV and 51 patients treated with S-1 were included in this study. Comparing the nal-IRI+5-FU/LV and S-1 groups, the median PFS was 2.95 months versus 2.10 months (p = 0.658), respectively, and the median OS was 8.51 months versus 5.83 months (p = 0.763), respectively. The ORR and DCR were 8.3% and 2.0% (p = 0.347) and 58.3% and 49.0% (p = 0.750) for the nal-IRI+5-FU/LV and S-1 groups, respectively. There were no significant differences in adverse events between the two groups. In a subgroup analysis, patients under 65 years of age treated with S-1 had a significantly better median OS (HR, 3.46; 95% CI: 1.02-11.71, p = 0.046).

CONCLUSION

Nal-IRI+5-FU/LV and S-1 were equally effective and safe as second-line therapy for PC. However, the results suggest that S1 is an option for younger patients, especially those under 65 years.