The Impact of Tumor Location on Resection and Survival for Pancreatic Ductal Adenocarcinoma

Abstract

BackgroundDifferences in clinical staging and survival among pancreatic head, body, and tail cancers are not well defined. We aim to identify the prognostic relevance of primary tumor location in patients undergoing treatment for pancreatic ductal adenocarcinoma (PDAC). Materials and methodsThe National Cancer Database was used to identify patients with PDAC from 1998 to 2011 (n = 175,556). Patients were categorized by primary tumor site into head (67.5%, n = 118,343), body (15.5%, n = 27,218), and tail (17.0%, n = 29,885) groups. Univariate and Cox regression analyses were used to determine covariates associated with overall survival (OS). ResultsPatients with head PDAC presented with earlier stage disease (39.2% Stage I/II versus 19.7% versus 16.0%, P < 0.001) and underwent resection more often (27.9% versus 10.7% versus 17.0%, P < 0.001) than those with body or tail tumors. Of surgically resected PDAC, those localized to the head had advanced pathologic stage (84.8% stage II/III versus 66.6% versus 65.6%, P < 0.001), higher nodal positivity (64.9% versus 45.8% versus 45%, P < 0.001), and worse tumor grade (35.9% poorly differentiated versus 29.5% versus 27.8%, P < 0.001). Despite increased utilization of adjuvant therapies (54.4% versus 45.6% versus 42.0%, P < 0.001), patients with head PDAC had inferior OS compared with those with body and tail tumors (P < 0.001). ConclusionsWhen examining patients with PDAC undergoing resection, tumor localization to the head is associated with improved resectability because they present earlier. Of resected PDACs, however, those localized to the head have worse OS compared with body and tail tumors. This discrepancy may represent a combination of lead time and selection biases and biologic differences between tumor sites.