In search of lost time: Delays in adjuvant therapy for pancreatic adenocarcinoma among under-resourced patient populations

Abstract

Background: The initiation of adjuvant chemotherapy for pancreatic adenocarcinoma within 12 weeks after surgery is recommended by the National Comprehensive Cancer Network. This study seeks to identify factors associated with delayed adjuvant chemotherapy and whether delays impact survival in under-resourced populations.

Methods: Patients with nonmetastatic pancreatic adenocarcinoma who received a definitive resection followed by adjuvant chemotherapy between 2006 and 2017 were queried from the National Cancer Database. Multivariate logistic regression models were constructed to determine the relationship between socioeconomic/clinical variables and delayed adjuvant chemotherapy. Kaplan Meier curves compared survival between under-resourced patients receiving delayed versus timely adjuvant chemotherapy.

Results: Among 25,008 patients, timely adjuvant chemotherapy varied by stage (stage 1: 67.9% vs stage 2: 75.8% vs stage 3: 89.2%; P < .001). Older age (odds ratio 1.02, 95% confidence interval 1.02-1.03; P < .001), Non-Hispanic Black race (odds ratio 1.25, 95% confidence interval 1.11-1.41; P < .001), increasing comorbidity score (odds ratio 1.18, 95% confidence interval 1.12-1.23; P < .001), 30-day readmission (odds ratio 1.45, 95% confidence interval 1.28-1.63; P < .001), and undergoing a Whipple (odds ratio 1.30, 95% confidence interval 1.16-1.44; P < .001) were associated with delayed adjuvant chemotherapy. Conversely, the highest neighborhood median income quartile (odds ratio 0.84, 95% confidence interval 0.73-0.97; P = .021), private insurance (odds ratio 0.59, 95% confidence interval 0.46-0.76; P < .001), Medicare (odds ratio 0.68, 95% confidence interval 0.52-0.88; P = .003), and receipt of neoadjuvant therapy (odds ratio 0.05, 95% confidence interval 0.04-0.06; P < .001) were associated with timely adjuvant chemotherapy. Non-Hispanic Black patients and patients with the lowest neighborhood education had worse overall survival when receiving delayed versus timely adjuvant chemotherapy.

Conclusion: Timely adjuvant chemotherapy for pancreatic adenocarcinoma was only achieved in 73.3% of patients. Age, race, comorbidities, median income, and insurance were identified as barriers. Delayed adjuvant chemotherapy was associated with worse survival among under-resourced populations.