The efficacy and safety of gemcitabine + nab-PTX for recurrence and refractory pancreatic cancer.

Abstract

485 Background: Gemcitabine + nab-Paclitaxel (GnP) is considered as one of the standard first-line chemotherapy for advanced pancreatic cancer (PC), but its efficacy and safety of GnP in patients with refractory or recurrent (Ref/Rec) PC has not been fully reported. Therefore, we conducted this retrospective analysis of GnP in patients with Ref/Rec PC. Methods: Consecutive patients with PC who received GnP at the University of Tokyo Hospital were retrospectively studied. Clinical outcomes in patients with Ref/Rec PC were compared with those in patients with PC receiving GnP as 1st line therapy. Dose intensity was calculated as the total amout of drug given in eight weeks. Tumor response was evaluated using RECIST 1.1 and adverse event using CTCAE ver 4.0. Progression free survival (PFS) were evaluated using the Kaplan-Meier method and compared by long-rank test. Cox regression models were used to calculate hazard ratios (HRs) to evaluate the prognostic factors in patients with Ref/Rec PC and in patients receiving GnP as 1stline therapy. Results: A total of 80 patients (37 as 1st line, 18 refractory and 25 recurrent) received GnP between January 2015 and July 2016. There were no significant differences in patient characteristics between 1st line therapy group and Ref/Rec group other than sex (Male in 41 vs. 67%). In relative dose intensity (RDI), there were no significant difference (75 vs. 72%). AE rates, both hematologic and non-hematologic, did not differ significantly between two groups. RDI was 75 vs. 72% for gemcitabine and 80 vs. 79% for nab-Paclitaxel. Response rate and disease control rate were 23 and 93% vs. 11 and 86%. The median PFS were 9.0 (95%CI: 4.9-13.9) vs. 5.5 (95%CI: 3.5-8.0) months (p = 0.06) and 1-year survival rate were 42.9 vs. 14.3% (p = 0.16). In the multivariate analyses, HRs of RDI < 70 were 2.44 (95%CI: 1.07-5.49, p = 0.04) in Ref/Rec group, while the association was not significant in the 1st line group (HR 1.70 [95%CI: 0.63-4.25], p = 0.28). Conclusions: GnP was safely administered in patients with Ref/Rec PC with DI comparable to 1st line therapy. However, PFS in refractory and recurrent group tended to be short compared to those receiving GnP as 1st line therapy. DI was associated with the prognosis only in Ref/Rec PC.