Patterns of Care and Outcomes of Adjuvant Chemoradiation for Node-Positive Pancreatic Adenocarcinoma

Purpose: The literature has been conflicting on the superiority of adjuvant chemoradiation over chemotherapy for node-positive adenocarcinoma of the pancreas following definitive surgery. We aimed to evaluate the patterns of care and outcomes of these two treatment options using the National Cancer Database (NCDB). Methods: Patients diagnosed with non-metastatic, node-positive adenocarcinoma of the pancreas from 2006 to 2014 who received oncologic resection with negative margins were identified in the NCDB. Patient- and clinical-related factors were compared between those who received adjuvant chemotherapy alone (aC) versus adjuvant chemoradiation (aCRT). Univariable and multivariable logistic regression was performed to assess for predictors of adjuvant chemoradiation use. The Kaplan-Meier method was used to assess overall survival (OS) and Cox regression analysis was used to assess impact of covariables on OS. Results: There were 3609 patients who met the study criteria, of which 2988 (82.8%) received chemotherapy alone and 621 (17.2%) who received chemoradiation. Median follow up for living patients was 33.8 months (IQR 22–51). On multivariable logistic regression, those who received treatment in more recent years of diagnoses (OR 0.21–0.37, p < 0.001) were less likely to receive aCRT over aC. Two-year OS for those who received chemo alone was 44.9% and for chemoradiation was 42.6% (p = 0.169). This finding was sustained on multivariable survival analysis (HR 0.99, p = 0.867). Conclusions: Adjuvant chemotherapy alone for adenocarcinoma of the pancreas is the predominant treatment of choice among US hospitals. There was no overall survival benefit noted in those who were treated with adjuvant chemoradiation.