1530P Gemcitabine/nab-paclitaxel versus (modified) FOLFIRINOX for palliative first-line treatment of advanced pancreatic cancer: A propensity score analysis

Gemcitabine/nab-Paclitaxel (GN) and (modified) FOLFIRINOX are standard first-line treatment options for advanced pancreatic ductal adenocarcinoma (PDAC), but no randomized head-to-head comparison between these treatments currently exists. We thus conducted a propensity score (PS) analysis of overall (OS) and progression-free survival (PFS) outcomes in a tri-center cohort of PDAC patients treated with either GN or (m)FOLFIRINOX. Four-hundred-fifty-five patients were included (table). In unadjusted analysis, both OS and PFS were highly similar in the GN group (n=297) and (m)FOLFIRINOX group (n=158). In detail, median-, 1-year, and 2-year OS estimates were 10.1 months, 42%, and 18% in the GN group, as compared to 11.2 months, 45%, and 12% in the (m)FOLFIRINOX group, respectively (log-rank p=0.783). In terms of PFS, median (4.6 vs. 4.8 months), 6-month (40% vs. 43%), and 1-year (9% vs. 9%) estimates were also highly comparable (log-rank p=0.717). However, patients in the (m)FOLFIRINOX group were significantly younger, less comorbid, had a lower prevalence of myocardial infarction, and a better ECOG performance status. These imbalances in confounders were removed by weighting the data with the PS. In PS analysis of survival outcomes, OS and PFS remained comparable between the two treatment groups. In detail, PS-weighted median-, 1-year, and 2-year OS estimates were 10.1 months, 42%, and 18% in the GN group, as compared to 10.1 months, 40%, and 13% in the (m)FOLFIRINOX group (PS-weighted log-rank p=0.449). PS-weighted median (4.6 vs. 4.4 months), 6-month (41% vs. 35%), and 1-year (7% vs. 7%) PFS estimates did again not differ (PS-weighted log-rank p=0.329).Table 1530PBaseline characteristicsVariableGN (n=297)(m)FOLFIRINOX (n=158)pAge (years)70 [62-74]63 [53-67]<0.0001Female sex123 (41%)64 (41%)0.851Charleson Comorbidity Index9 [8-10]8 [7-9]<0.0001Myocardial infarction23 (8%)4 (3%)0.035ECOG: 087 (30%)99 (63%)<0.0001Tumor location: Pancreatic head175 (61%)74 (50%)0.024Primary palliative setting242 (81%)140 (89%)0.033Surgery of primary tumor65 (22%)18 (11%)0.006Prior adjuvant chemotherapy44 (15%)14 (9%)0.085Tumor extent: Metastatic231 (78%)121 (77%)0.282CA 19-9 (U/mL)959 [74-6390]1555 [135-12278]0.117Data are medians [25th-75th percentile] or absolute frequencies (%). Open table in a new tab Data are medians [25th-75th percentile] or absolute frequencies (%). In this propensity score analysis of advanced PDAC patients undergoing 1st-line combination chemotherapy with GN or (m)FOLFIRINOX, OS and PFS did not differ between these two treatments.