Tumors of the Ampulla of Vater: Histopathologic Classification and Predictors of Survival

BackgroundThe histology and clinical behavior of ampullary tumors vary substantially. We speculated that this might reflect the presence of two kinds of ampullary adenocarcinoma: pancreaticobiliary and intestinal.Study DesignWe analyzed patient demographics, presentation, survival (mean followup 44 months), and tumor histology for 157 consecutive ampullary tumors resected from 1989 to 2006. Histologic features were reviewed by a pathologist blinded to clinical outcomes. Survival was compared using Kaplan-Meier/Cox proportional hazards analysis.ResultsThere were 33 benign (32 adenomas and 1 paraganglioma) and 124 malignant (118 adenocarcinomas and 6 neuroendocrine) tumors. One hundred fifteen (73%) patients underwent a Whipple procedure, 32 (20%) a local resection, and 10 (7%) a palliative operation. For adenocarcinomas, survival in univariate models was affected by jaundice, histologic grade, lymphovascular, or perineural invasion, T stage, nodal metastasis, and pancreaticobiliary subtype (p < 0.05). Size of tumor did not predict survival, nor did cribriform/papillary features, dirty necrosis, apical mucin, or nuclear atypia. In multivariate models, lymphovascular invasion, perineural invasion, stage, and pancreaticobiliary subtype predicted survival (p < 0.05). Patients with pancreaticobiliary ampullary adenocarcinomas presented with jaundice more often than those with the intestinal kind (p = 0.01) and had worse survival.ConclusionsIn addition to other factors, tumor type (intestinal versus pancreaticobiliary) had a major effect on survival in patients with ampullary adenocarcinoma. The current concept of ampullary adenocarcinoma as a unique entity, distinct from duodenal and pancreatic adenocarcinoma, might be wrong. Intestinal ampullary adenocarcinomas behaved like their duodenal counterparts, but pancreaticobiliary ones were more aggressive and behaved like pancreatic adenocarcinomas.