title: Extra-ampullary duodenal adenocarcinoma.
abstract: Extra-ampullary duodenal adenocarcinomas are rare, and when studied, frequently have been grouped with jejunoileal adenocarcinomas. Nevertheless, anecdotal experiences suggest that these neoplasms may present 2 or more distinct phenotypes. To better characterize these neoplasms, we performed a retrospective review of 38 cases with a special focus on the morphologic and immunophenotypic characteristics and their clinicopathologic significance. Our cohort of extra-ampullary duodenal adenocarcinomas was classified on the basis of the morphologic features into gastric type (n=19, 50%), intestinal type (n=14, 37%), pancreaticobiliary type (n=2, 5%), and others (n=3, 8%). Most gastric-type adenocarcinomas (n=18, 95%) developed in the proximal duodenum, whereas the other types were located equally in the proximal and distal duodenum. Intestinal-type dysplasia was present at the periphery of 8 (57%) intestinal-type adenocarcinomas, and 8 (42%) gastric-type adenocarcinoma were associated with gastric-type dysplasia. Gastric foveolar metaplasia (n=12) and Brunner gland hyperplasia (n=10) were exclusively recognized adjacent to gastric-type adenocarcinomas. Notably, intestinal-type histology and the absence of lymph node metastasis were significantly associated with favorable disease-free survival in univariate and multivariate analyses. In summary, this study demonstrated that 2 major subsets of extra-ampullary duodenal adenocarcinoma, intestinal type and gastric type, are associated with distinct histopathologic features and clinical behavior.
authors.affiliation: *Department of Pathology, Massachusetts General Hospital Boston, MA †Department of Pathology, University of Tokyo, Tokyo, Japan ‡Division of Anatomical Pathology, Queen Elizabeth II Health Sciences Centre, Halifax, NS, Canada.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Ushiku
authors.forename: Thomas
authors.initials: T
authors.lastname: Arnason
authors.forename: Masashi
authors.initials: M
authors.lastname: Fukayama
authors.forename: Gregory Y
authors.initials: GY
authors.lastname: Lauwers
mesh_terms: D000230:Adenocarcinoma / Q000276:immunology / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D018572:Disease-Free Survival; D004379:Duodenal Neoplasms / Q000276:immunology / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D004386:Duodenum / Q000276:immunology / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D053208:Kaplan-Meier Estimate; D008297:Male; D008679:Metaplasia; D008875:Middle Aged; D015999:Multivariate Analysis; D010641:Phenotype; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors
chemical_list: D014408:Biomarkers, Tumor