title: Adenocarcinoma of the thymus, enteric type: report of 2 cases, and proposal for a novel subtype of thymic carcinoma.
abstract: We report 2 cases of primary thymic adenocarcinoma with enteric differentiation. One carcinoma occurred in a 41-year-old man as a 7-cm-diameter cystic tumor and the other one in a 39-year-old woman as a 6-cm-diameter solid mass. Both tumors were located in the anterior mediastinum. Clinical staging did not reveal any extrathymic tumor. Histologically, the tumors were classified as adenocarcinoma, not otherwise specified, and a mucinous (colloid) carcinoma, respectively. Immunohistochemically, both tumors were positive for cytokeratin 20 (CK20), CDX2, and carcinoembryonic antigen, reflecting enteric differentiation. A review of the literature on 43 other cases of primary thymic adenocarcinomas suggested 11 further cases with enteric differentiation, as assessed by CK20 and/or CDX2 expression. We propose that thymic adenocarcinoma with enteric differentiation represents a novel subtype of thymic carcinoma. It is mostly of mucinous morphology and frequently associated with thymic cysts. The clinical outcome is variable. Recognition of primary thymic adenocarcinoma with enteric differentiation is helpful for the differentiation from metastatic disease, mainly from the gastrointestinal tract.
authors.affiliation: *Department of Thoracic Surgery, Division of Surgery Departments of †Pathology §Radiology, Medical University Vienna ∥Department of Pulmology and Karl Landsteiner Institute of Clinical and Experimental Pneumology, Hietzing Hospital, Vienna, Austria ‡Institute of Pathology, University Medical Center Mannheim, University of Heidelberg, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Moser
authors.forename: Ana Iris
authors.initials: AI
authors.lastname: Schiefer
authors.forename: Stefan
authors.initials: S
authors.lastname: Janik
authors.forename: Alexander
authors.initials: A
authors.lastname: Marx
authors.forename: Helmut
authors.initials: H
authors.lastname: Prosch
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Pohl
authors.forename: Barbara
authors.initials: B
authors.lastname: Neudert
authors.forename: Anke
authors.initials: A
authors.lastname: Scharrer
authors.forename: Walter
authors.initials: W
authors.lastname: Klepetko
authors.forename: Leonhard
authors.initials: L
authors.lastname: Müllauer
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000737:chemistry / Q000145:classification / Q000473:pathology* / Q000601:surgery; D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D002454:Cell Differentiation; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D013945:Thymoma / Q000737:chemistry / Q000145:classification / Q000473:pathology* / Q000601:surgery; D013953:Thymus Neoplasms / Q000737:chemistry / Q000145:classification / Q000473:pathology* / Q000601:surgery; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden
chemical_list: D014408:Biomarkers, Tumor