title: Ductal and acinar differentiation in pancreatic endocrine tumors.
abstract: Rare pancreatic endocrine tumors consisting of both exocrine and endocrine components have been reported sporadically. We investigated the ductal and acinar differentiation in pancreatic endocrine tumors. In immunohistochemical studies of 28 pancreatic endocrine tumors, staining with anti-carcinoembryonic antigen (CEA) or CA19-9 antibody indicated ductal differentiation, while staining with anti-amylase or anti-trypsin antibody indicated acinar differentiation. K-ras gene mutations and p53 gene alterations also were studied. Ten tumors were immunoreactive for CEA or CA19-9. Five tumors diffusely immunoreactive for CEA or CA19-9, in addition to endocrine markers, were diagnosed as duct-endocrine cell tumors of the pancreas. Two tumors diffusely immunoreactive for CEA or CA19-9 and also for pancreaticogut hormones as well as endocrine markers were diagnosed as duct-acinarendocrine cell tumors. These tumors showed uniform histologic features and synchronous ductal, acinar, and endocrine differentiation, distinct from the coexisting different cellular populations seen in collision tumors. All tumors were malignant. These duct-endocrine cell tumors or duct-acinar- endocrine cell tumors of the pancreas may be derived from a stem cell that retains the capability of expressing either an exocrine or endocrine phenotype. Only one K-ras gene mutation and no p53 gene alterations were detected in these tumors, which suggests that they constitute an entity with a different origin than ductal carcinomas.
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, Japan.
authors.forename: Terumi
authors.initials: T
authors.lastname: Kamisawa
authors.forename: Yuyang
authors.initials: Y
authors.lastname: Tu
authors.forename: Naoto
authors.initials: N
authors.lastname: Egawa
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Ishiwata
authors.forename: Kouji
authors.initials: K
authors.lastname: Tsuruta
authors.forename: Astutake
authors.initials: A
authors.lastname: Okamoto
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Hayashi
authors.forename: Morio
authors.initials: M
authors.lastname: Koike
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Yamaguchi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D018395:CA-19-9 Antigen / Q000032:analysis; D002272:Carcinoembryonic Antigen / Q000032:analysis; D002276:Carcinoid Tumor / Q000473:pathology*; D018267:Carcinoma, Acinar Cell / Q000473:pathology*; D021441:Carcinoma, Pancreatic Ductal / Q000473:pathology*; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010179:Pancreas / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen