The Influence of Adjuvant Radiation Therapy Dose on Overall Survival for Resected Pancreatic Adenocarcinoma

• Type of Material: Article
• Authors: William A. Hall, Emory University; Lauren E. Colbert, Emory University; Yuan Liu, Emory University; Theresa Wicklin Gillespie, Emory University; Joseph Lipscomb, Emory University; Claire Hardy, Emory University; David A Kooby, Emory University; Roshan S. Prabhu, Emory University; John Kauh, Emory University; Jerome C Landry, Emory University
• Language: English
• Date: 2013-06-15
• Publisher: Wiley: 12 months
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2013 American Cancer Society
• Final Published Version (URL): http://onlinelibrary.wiley.com/doi/10.1002/cncr.28047/abstract;jsessionid=2C09F806037BE989E9A8F33130D21638.f04t04
• Title of Journal or Parent Work: Cancer
• ISSN: 0008-543X
• Volume: 119
• Issue: 12
• Start Page: 2350
• End Page: 2357
• Grant/Funding Information: This work was supported in part by the National Center forAdvancing Translational Sciences of the National Institutes ofHealth under Award Number UL1TR000454 and TL1TR000456.
• Keywords: Pancreatic Adenocarcinoma adjuvant Radiation Therapy; Resected Pancreatic Adenocarcinoma; Post-operative management in resected pancreatic adenocarcinoma; Adjuvant radiation dose in resected pancreatic adenocarcinoma
• Research Categories: Health Sciences, Oncology; Health Sciences, Medicine and Surgery; Health Sciences, Epidemiology

Abstract

Background Adjuvant radiation therapy (A-RT) for resected pancreatic adenocarcinoma (PAC) is controversial. We aim to determine if there is an association between overall survival (OS) and A-RT dose. Methods National Cancer Data Base (NCDB) data were obtained for all patients who underwent A-RT for resected PAC from 1998-2002. Univariate (UV) and multivariable (MV) survival analysis were performed along with Kaplan-Meier (KM) estimates for A-RT levels < 40 Gy, 40 to < 50 Gy, 50 to < 55 Gy, and ≥ 55 Gy. Results 1,385 patients met inclusion criteria. Median age was 64 (29-87); all patients underwent surgical resection and A-RT +/- chemotherapy. 231 patients were AJCC 5th edition stage I, 273 stage II, 734 stage III, and 126 stage IVA; 21 were unknown. Median A-RT dose was 45 Gy (1.63 Gy-69 Gy). Median OS was 21 months (95% CI 19 - 23). On MV analysis A-RT dose < 40 Gy (HR, 1.30 [95% CI 1.03-1.66]; p = 0.031), A-RT dose 40 to < 50 Gy (HR, 1.17 [95% CI 1.00-1.37]; p = 0.05), and A-RT dose ≥ 55 Gy (HR, 1.44 [95% CI 1.08-1.93]; p = 0.013) predicted worse OS when compared with the reference category of 50 to < 55 Gy. Conclusions A-RT doses of less than 40 Gy, 40 to < 50 Gy, and ≥ 55 Gy were associated with inferior OS. The dose of A-RT delivered appears to influence OS and a prospective study evaluating the addition of optimally delivered A-RT for resected PAC is needed.