Modified FOLFIRINOX as a second-line therapy following gemcitabine plus nab-paclitaxel therapy in metastatic pancreatic cancer

Background There is no established second-line treatment after failure of gemcitabine plus nab-paclitaxel (GnP) therapy for metastatic pancreatic cancer (MPC). The purpose of this study was to evaluate the efficacy and tolerability of the modified FOLFIRINOX (mFFX) as a second-line therapy for MPC and to investigate prognostic factors for survival. Methods From 2015 to 2019, we retrospectively reviewed the medical records of consecutive patients receiving mFFX for MPC after failure of GnP therapy. Patients were treated every 2 weeks with mFFX (intravenous oxaliplatin 85 mg/m 2 , intravenous irinotecan 150 mg/m 2 , and continuous infusion of 5-fluorouracil 2400 mg/m 2 for 46 h without bolus infusion). Results In total, 104 patients received mFFX. The median overall survival (OS) was 7.0 months (95% confidence interval [CI]: 6.2–9.8) and the progression-free survival (PFS) 3.9 months (95% CI 2.8–5.0). The objective response rate was 10.6% and the disease control rate 56.7%. The median relative dose intensities of oxaliplatin, irinotecan, and infusional 5-FU were 80.0% (range 21.5–100%), 77.2% (range 38.1–100%), and 85.9% (range 36.9–100%), respectively. Grade 3–4 toxicities were reported in 57 patients (54.8%), including neutropenia, leukopenia, anemia, febrile neutropenia, and peripheral sensory neuropathy. Glasgow prognostic score and carcinoembryonic antigen level were independently associated with survival. Our prognostic model using these parameters could classify the patients into good ( n = 38), intermediate ( n = 47), and poor ( n = 19) prognostic groups. The median OS and PFS time was 14.7 (95% CI 7.6–16.3) and 7.6 months (95% CI 4.1–10.5) for the good prognostic factors, 6.5 (95% CI 5.5–10.0) and 3.6 months (95% CI 2.7–4.8) for the intermediate prognostic factors and 5.0 (95% CI 2.9–6.6) and 1.7 months (95% CI 0.9–4.3) for the poor prognostic factors, respectively. Conclusions The mFFX showed to be a tolerable second-line treatment for MPC after GnP failure. Our prognostic model might be useful for deciding whether mFFX is indicated in this setting.