Overall Survival Prediction and Usefulness of Second-Line Chemotherapy in Advanced Pancreatic Adenocarcinoma

Background In advanced pancreatic ductal adenocarcinoma (aPDAC), there is no consensual strategy for second-line chemotherapy (L2). Better discrimination of overall survival (OS) may help clinical decision-making. We aimed to predict OS from the beginning of L2 and to assess the benefit from chemotherapy among the identified risk groups. Methods Analyses were derived from all consecutive aPDAC patients treated at Besancon University Hospital, Besancon, France, between January 2003 and December 2013 (n = 462). The association of 50 parameters with OS was evaluated using univariate and multivariable Cox analyses. Based on the final model, a prognostic nomogram and score were developed and externally validated. Patients in the external validation cohort who received L2 (n = 163) were treated at three French institutions between January 2010 and April 2016. All statistical tests were two-sided. Results In the development cohort, 395 patients (85.5%) were eligible for L2, of which 261 (66.1%) were treated. Age, smoking status, liver metastases, performance status, pain, jaundice, ascites, duration of first-line, and type of L2 regimen were identified as independent prognostic factors for OS in L2. The score determined three groups with median OS of 11.3 months (95% confidence interval [CI] = 9.1 to 12.9 months), 3.6 months (95% CI = 2.6 to 4.7 months), and 1.4 months (95% CI = 1.2 to 1.7 months), for low-, intermediate-, and high-risk groups, respectively ( P < .001). By applying the score in the population eligible for L2 but untreated, the chemotherapy benefit was statistically significant across all groups, but with a magnitude of the effect decreased statistically significantly from low- to high-risk groups ( P = .001 for treatment and risk groups interaction term). The ability of the score to discriminate OS was confirmed in the external validation cohort. Conclusions This prognostic nomogram and score in patients with aPDAC can accurately predict OS before administration of L2 and may help clinicians in their therapeutic decisions.