Outcomes of neoadjuvant therapy for locally advanced pancreatic adenocarcinoma: an intention to treat analysis with comparison to patients with resectable and borderline resectable disease

Abstract

Background: Neoadjuvant therapy (NAT) for pancreatic ductal adenocarcinoma (PDAC) has gained popularity. However, results of NAT are rarely compared to other cohorts or on an intention-to-treat basis. This study presented outcomes from a centre where NAT was standard of care for patients with locally advanced (LA) disease and up-front resection was standard of care for patients with borderline resectable (BR) venous disease or resectable disease. Methods: Patients with PDAC between 2013 and 2017 (n=345) were classified as resectable, BR and LA, according to NCCN criteria. Results: Some 16% (54/345) were BR and 20% (70/345) were LA. Patients with LA disease were younger than those with BR or resectable disease (64vs65vs68 years, p< 0.001). NAT was used 79% of LA disease, 4% of BR, and none of the resectable patients (p< 0.001). There were no differences in survival between resectable, BR and LA disease (19vs15vs19 months; p=0.585). Resection rates were higher in resectable disease followed by BR and LA (78%vs65%vs30%; p< 0.001). Among those with LA disease 44% (31/70) did not receive any surgery. Among those that did the median survival was 31 months (HR: 0.29, 95% CI: 0.11 - 0.79, p=0.015). Conclusion: Survival between patients with resectable, BR or LA disease is equivalent. A large proportion of patients with LA disease never undergo surgery. If this can be improved, then NAT is likely to be associated with increased survival. However, studies of quality of life and patient preference are urgently required, as these are almost certainly affected by NAT.