Impact of Nab-Paclitaxel-based Second-line Chemotherapy in Metastatic Pancreatic Cancer

Background: Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with median survival of 20% at 1 year. We conducted a retrospective study to assess the efficacy and tolerability of nab-paclitaxel (NP)-based second-line chemotherapy in metastatic PDAC. Patients and Methods: The Indiana University Simon Cancer Center pancreatic cancer program was used to identify patients with metastatic PDAC who received any second-line chemotherapy. Demographic, clinical and outcomes data were collected by manual chart abstraction. Patients were divided into two groups: a NP-based treatment group and a non-NP-based treatment group. Overall (OS) and progression-free (PFS) survival were estimated using Kaplan-Meier method. Cox proportional hazards regression was used for multivariate analyses. Results: A total of 120 patients received second-line chemotherapy. There were 47 (39%) patients in the NP group and 73 (61%) in the non-NP group. As compared to the non-NP group, the NP group showed improved median PFS [2.8 vs. 2.1 months; hazard ratio (HR)=0.62, 95% confidence interval (CI)=0.38-1.02; p=0.06] and median OS (7.5 vs. 4.7 months; HR=0.67, 95% CI=0.45-1.00; p=0.05). Multivariate analyses adjusted for age showed a significantly improved PFS (adjusted HR=0.60, 95% CI=0.36-0.98; p=0.04) and a suggestion of improved OS (adjusted HR=0.67, 95% CI=0.44-1.01, p=0.05) in the NP group as compared to non-NP group. Serious adverse events were seen in 13.3% of patients in the non-NP group and 17.1% patients in the NP group. Conclusion: In a single-institution retrospective cohort study, we report a significant improvement in the PFS and suggestion of improvement in the OS with NP-based second-line chemotherapy with an acceptable toxicity rate.