Impact of intensified chemotherapy in metastatic pancreatic ductal adenocarcinoma (PDAC) in clinical routine in Europe.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is associated with poor prognosis. Gemcitabine is the standard chemotherapy for patients with metastatic pancreatic adenocarcinoma (MPA). Randomized clinical trials evaluating intensified chemotherapies including FOLFIRINOX and nab-paclitaxel plus gemcitabine (NAB+GEM) have shown improvement in survival. Here, we have evaluated the efficacy of intensified chemotherapy versus gemcitabine monotherapy in real-life settings across Europe. METHODS: A retrospective multi-center study including 1056 MPA patients, between 2012 and 2015, from nine centers in UK, Germany, Italy, Hungary and the Swedish registry was performed. Follow-up was at least 12 months. Cox proportional Harzards regression was used for uni- and multivariable evaluation of prognostic factors. RESULTS: Of 1056 MPA patients, 1030 (98.7%) were assessable for survival analysis. Gemcitabine monotherapy was the most commonly used regimen (41.3%), compared to FOLFIRINOX (n = 204, 19.3%), NAB+GEM (n = 81, 7.7%) and other gemcitabine- or 5-FU-based regimens (n = 335, 31.7%). The median overall survival (OS) was: FOLFIRINOX 9.9 months (95%CI 8.4-12.6), NAB+GEM 7.9 months (95%CI 6.2-10.0), other combinations 8.5 months (95%CI 7.7-9.3) and gemcitabine monotherapy 4.9 months (95%CI 4.4-5.6). Compared to gemcitabine monotherapy, any combination of chemotherapeutics improved the survival with no significant difference between the intensified regimens. Multivariable analysis showed an association between treatment center, male gender, inoperability at diagnosis and performance status (ECOG 1-3) with poor prognosis. CONCLUSION: Gemcitabine monotherapy was predominantly used in 2012-2015. Intensified chemotherapy improved OS in comparison to gemcitabine monotherapy. In real-life settings, the OS rates of different treatment approaches are lower than shown in randomized phase III trials.