Real-world survival outcomes of using neoadjuvant chemotherapy in pancreatic cancer patients: Findings from the PURPLE clinical registry.

Abstract

e16755 Background: Only a minority of pancreatic cancer patients (pts) are surgical candidates at presentation. Neoadjuvant chemotherapy (NAT) is proposed to increase the proportion of surgical candidates. This study investigates the impact of NAT in routine care of pancreatic cancer. Three cohorts were analysed, patients with early-stage resectable (ER), borderline resectable (BR) and locally advanced (LA) pancreatic cancer. Within these groups, survival outcomes of those undergoing immediate resection (IR) was compared to those receiving NAT with nab-paclitaxel and Gemcitabine (nabPGem) and NAT with FOLFIRINOX. Methods: The PURPLE registry consists of 1492 pancreatic cancer pts from 27 hospitals in Australia, New-Zealand and Singapore, collated between 2016-2019. After exclusion of LA unresectable and metastatic pts (n = 809), 683 pts were included. Kaplan-Meir curves estimated survival between groups with 95% confidence intervals. Multivariable cox proportional hazards models adjusted for age, gender and ECOG performance status. Results: Of 683 pts, 107 received NAT and 576 underwent IR. Those in the NAT group had favourable characteristics, including younger age (mean 63 vs. 66 yrs, p < 0.01) and higher proportion of ECOG 0 vs. ≥1 (64% vs 46%) than those undergoing IR. Of those that received NAT, 64 received FOLFIRINOX and 35 nabPGem. Those receiving FOLFIRINOX were younger (mean: 60 vs. 67 yrs, p < 0.01) and were more likely ECOG 0 compared to those receiving nabPGem (72% vs. 46%, p = 0.02). Resection rates for pts undergoing IR vs. NAT were 88% vs. 50% in ER and 16% vs. 43% in BR. Rates of R0 resection margins in pts undergoing IR vs. NAT were 54% vs. 25% in ER and 6% vs. 21% in BT. Comparing ER to BR, mOS was 29.9 vs. 20.3 mths (HR: 0.54, p < 0.01). Within BR, mOS was 20.3 vs. 17.2 mths for NAT vs. IR (HR: 1.11, p = 0.74). Comparing those receiving FOLFIRINOX vs. nabPGem over all groups, mOS was 22 mths vs. 12 mths (HR: 0.31, p < 0.01). Conclusions: Real-world data confirms the use of NAT remains infrequent in this Asia-Pacific population. The use of FOLFIRINOX was associated with better survival than nabPGem based on this observational study. Improved methods for treatment selection are required. Potential biomarkers including circulating tumor DNA are being explored in the DYNAMIC-Pancreas clinical trial.