Clinical outcome of modified FOLFIRINOX versus gemcitabine plus nab-paclitaxel as first line chemotherapy in metastatic pancreatic cancer.

Abstract

438 Background: FOLFIRINOX and Gemcitabine plus nab-paclitaxel (GN) have been established as first line chemotherapy in metastatic pancreatic cancer (mPC). But few data support preferable first line choice of these two regimens in “real-world” clinical setting. Methods: We retrospectively enrolled 135 chemotherapy-naive mPC patients treated with modified FOLFIRINOX (mFFX) or GN at National Cancer Center Hospital East between December 2013 and September 2015. mFFX is a modified regimen of reduced dose of irinotecan 150mg/m2 and eliminated bolus 5-FU from original FFX. GN consists of gemcitabine 1000mg/m2 plus nab-paclitaxel 125mg/m2 day1,8,15 every 4 weeks. We compared characteristics, efficacy and adverse events between mFFX and GN. Results: Seventy patients were treated with mFFX and 65 patients with GN as first line therapy. Demographic and baseline characteristics (mFFX/GN) were similar as follows: ECOG performance status (0-1): 100% / 99%, Gender (male): 66% / 69%, liver metastasis: 56%/49%, peritoneal metastasis: 34% / 31%, prior biliary drainage: 21%/17%, median observation period: 330 / 265 days, respectively. The population of elderly patients ( > 75y) was smaller in mFFX than GN (4.3% vs. 12%, p = 0.05). Objective response rate (27% vs. 39%, p = 0.02) and disease control rate (79% vs. 92%, p = 0.02) were significantly lower in mFFX than in GN. Median OS was 11.5 months (95% CI: 9.7-16.8) in mFFX and 14.0 months (95% CI: 12.2 - not reached) in GN. Median PFS was 5.7 months (95% CI: 3.4-7.1) in mFFX and 6.5 months (95% CI: 6.1-7.9) in GN. One-year survival rate was significantly higher in GN than in mFFX (44% vs. 67%, p = 0.0006). Incidences of grade 3 or 4 neutropenia (47% vs. 45%), diarrhea (1.4% vs. 2.0%), and peripheral neuropathy (4.2% vs. 4.6%) were similar in each group. On the other hand, incidences of febrile neutropenia (8.5% vs. 2.0%, p = 0.06) and G-CSF use rate (21% vs. 0%, p < 0.0001), anorexia (13% vs. 3%, p = 0.03) were significantly higher in mFFX than those of GN. Conclusions: Patients treated with GN showed more favorable efficacy and survival. Incidences of most adverse events did not differ between mFFX and GN,whereas febrile neutropenia occurred more frequently in mFFX.