Author(s): Amanda Carlson
Mentor(s): George Molina, Raja Narayan
Institution BYU
Introduction: Pancreatic cancer (PC) often recurs locally after surgical resection with curative intent. Preoperative radiation, also known as neoadjuvant radiation therapy (NRT) and which may consist of chemoradiation, has been found to be beneficial in reducing local recurrence and improving overall survival (OS) among patients with esophageal and rectal cancers (ERC). However, its efficacy in PC remains uncertain, with mixed results from various trials. The Alliance A021501 trial indicated better OS with neoadjuvant chemotherapy alone compared to adding hypofractionated NRT, while the Dutch PREOPANC trial reported improved 5-year survival with NRT. Numerous studies have linked hospital surgical volume to patient outcomes. However, few have assessed the impact of hospital radiation volume on postoperative and oncologic outcomes, despite the complexity of NRT. This study aims to evaluate the impact of institutional NRT volume on postoperative and oncologic outcomes in PC patients. Methods: This retrospective cohort study utilized data from the National Cancer Database (NCDB). Two cohorts were identified to define hospital volume: one for patients who received NRT for esophageal/rectal adenocarcinoma or squamous cell carcinoma and another for patients who received NRT for pancreatic adenocarcinoma. Hospital NRT volume was categorized into low (<90th percentile) and high (≥90th percentile) based on mean annual patient volume for ERC and PC. For the remaining analysis, the PC cohort was refined to include only patients who underwent surgical resection. Univariable analysis compared patient characteristics across hospital volume groups. Multivariable logistic regression models assessed the association between hospital NRT volume and surgical margin status, as well as 30-day readmission rates. OS was analyzed using a Cox proportional hazards model, and Kaplan-Meier survival curves compared OS between high and low NRT volume hospitals. Results: Between 2011 and 2019, 2,879 PC patients who received NRT followed by surgical resection were identified for this study. Patients treated at high NRT volume hospitals had a higher median income, were more likely to be treated at academic facilities, and had larger tumors compared to those at low volume hospitals. Surgical margin status and 30-day readmission rates were not significantly associated with hospital NRT volume. High NRT volume hospitals were associated with improved OS for both ERC and PC. The median OS for high NRT volume hospitals was 36.0 months for ERC and 35.9 months for PC, compared to 31.3 months and 29.4 months, respectively, for low volume hospitals.