title: Cellular hamartoma resembling gastrointestinal stromal tumor: a solid tumor of the pancreas expressing c-kit (CD117).
abstract: Solid tumors of the pancreas are usually neoplastic. We report on two adult patients, each with a solid tumor of the pancreas that presented with an unusual histology and seemed to follow a benign course. The tumors, one located in the body and one in the tail, were well demarcated and composed of irregularly arranged but well-differentiated acini and small intralobular and interlobular ducts embedded in predominantly hypocellular fibrotic tissue that contained fascicles of cytologically bland spindle cells. Islets were lacking, but immunohistochemical staining for chromogranin A and insulin revealed individual scattered insulin-producing cells distributed between acinar and ductal cells. The spindle cell component tissue showed coexpression of CD34, c-kit (CD117) and bcl-2. The follow-up (2 and 4 years) of the patients was uneventful. We propose to designate the tumors as 'cellular hamartoma resembling gastrointestinal stromal tumor.
authors.affiliation: Department of Pathology, University of Kiel, Germany. upauser@path.uni-kiel.de
authors.forename: Ursula
authors.initials: U
authors.lastname: Pauser
authors.forename: Maria T S
authors.initials: MT
authors.lastname: da Silva
authors.forename: Jörg
authors.initials: J
authors.lastname: Placke
authors.forename: David S
authors.initials: DS
authors.lastname: Klimstra
authors.forename: Günter
authors.initials: G
authors.lastname: Klöppel
mesh_terms: D018952:Antigens, CD34 / Q000378:metabolism; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000378:metabolism / Q000473:pathology*; D006222:Hamartoma / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010182:Pancreatic Diseases / Q000378:metabolism / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D019089:Stem Cell Factor / Q000378:metabolism*
chemical_list: D018952:Antigens, CD34; D019253:Proto-Oncogene Proteins c-bcl-2; D019089:Stem Cell Factor