Treatment Outcomes and Prognostic Factors of Gemcitabine Plus Nab-Paclitaxel as Second-Line Chemotherapy after Modified FOLFIRINOX in Unresectable Pancreatic Cancer

SIMPLE SUMMARY: There is no established standard second-line chemotherapy after modified FOLFIRINOX for unresectable pancreatic cancer. While gemcitabine plus nab-paclitaxel is often used as second-line chemotherapy after modified FOLFIRINOX, outcomes and prognostic factors of second-line gemcitabine plus nab-paclitaxel have been unclear. This study revealed that median overall survival (OS) and progression-free survival (PFS) of second-line gemcitabine plus nab-paclitaxel were 7.2 months and 3.6 months, respectively. Performance status, modified Glasgow prognostic score, and neutrophil-to-lymphocyte ratio were independently associated with overall survival. Our prognostic model using these parameters classifies patients into the good and poor prognosis groups. Median OS and PFS were longer in the good prognosis group than in the poor prognosis group. Efficacy of second-line gemcitabine plus nab-paclitaxel was notably limited, particularly in the poor prognosis group. ABSTRACT: Outcomes and prognostic factors of second-line gemcitabine plus nab-paclitaxel (GnP) after modified FOLFIRINOX (mFFX) for unresectable pancreatic cancer were unclear. We retrospectively analyzed consecutive patients with unresectable pancreatic cancer treated with GnP after first-line mFFX treatment between March 2015 and March 2022 at our hospital. A total of 103 patients were included. Median overall survival (OS) from the start of first-line and second-line treatments was 14.9 months and 7.2 months, respectively. Median progression-free survival (PFS) was 3.6 months. Performance status, modified Glasgow prognostic score, and neutrophil-to-lymphocyte ratio were independently associated with OS. Our prognostic model using these parameters classifies patients into good (n = 70) and poor (n = 33) prognosis groups. Median OS and PFS were longer in the good prognosis group than in the poor prognosis group (OS: 9.3 vs. 3.8 months, p < 0.01; PFS: 4.1 vs. 2.3 months, p < 0.01). Grade 3/4 adverse events were observed in 70.9% of patients, with neutropenia being the most frequent. While GnP as second-line treatment was well-tolerated, efficacy of second-line gemcitabine plus nab-paclitaxel was notably limited, particularly in the poor prognosis group.