FOLFIRINOX de-escalation in advanced pancreatic cancer (aPC): A multicenter real-life study.

Abstract

4639 Background: FOLFIRINOX (5FU, irinotecan, and oxaliplatin) is a reference first line (L1) of chemotherapy (CT) in fit patients (Pts) with advanced pancreatic cancer (aPC). Limiting toxicities (in particular, neuropathy) are frequent and maintaining quality of life without a lack of efficacy is a crucial need. Modalities and efficacy of maintenance strategy in aPC remain scarcely studied. Our study describes the French practices of a FOLFIRINOX de-escalation and maintenance in a real-life multicentric cohort. Methods: We performed a retrospective multicentric study in 5 French centers. Pts receiving FOLFIRINOX L1 for aPC were recruited between January 2011 and December 2018. FOLFIRINOX de-escalation was defined as stopping oxaliplatin and/or irinotecan in patients without tumor progression, after at least 4 cycles of FOLFIRINOX. Maintenance schedules were oral capecitabine or intravenous (IV) 5FU, FOLFOX or FOLFIRI. Primary endpoint was overall survival (OS). Secondary endpoints were first progression-free survival (PFS1) and, in case of reintroduction of FOLFIRINOX, second progression free survival (PFS2). OS and PFS were estimated using the Kaplan-Meier method and compared using the log-rank test. Results: Among the 321 patients included, 147 (46%) received a maintenance therapy. Median age was 60.0 (53-66), 35 (24%) had locally advanced PC and 91 (62%) had metastatic PC. The median number of cycles of FOLFIRINOX was 9.0 (6.0-11.0). Median OS was 16.1 months (95%CI=13.7-20.3). Median PFS1 was 9.4 months (95%CI=8.5-10.4). The preferred maintenance regimen was FOLFIRI in 66 (45%), vs fluoropyrimidine (FP) in 52 (35%) and FOLFOX in 25 (17%). Among 118 Pts who received a maintenance CT with FP or FOLFIRI, there was no difference in PFS1 (median: 10.1 vs 9.0, respectively, p=0.33) or OS (median: 16.6 versus 18.7, p=0.86) between the 2 maintenance regimens. After progression under maintenance CT with FOLFIRI or FP, reintroduction of FOLFIRINOX was performed in 20.2% of Pts, with a median PFS2 of 2.8 months (95%CI=2.0-22.3). The rates of G3-4 toxicity were significantly higher during FOLFIRI maintenance CT than with FP (41% vs 22%, p=0.03), especially neuropathy (73% vs 9%). Conclusions: FOLFIRINOX de-escalation in aPC is largely used in France. Fluoropyrimidine maintenance chemotherapy appears to be as effective as FOLFIRI.