title: Main pancreatic duct obstruction due to a small nonfunctioning endocrine tumor of the pancreas.
abstract: A 65-year-old Japanese male was referred to our hospital for evaluation of a main pancreatic duct obstruction. Two months previously, he had suffered an attack of acute pancreatitis that was resolved with conservative treatment. Dynamic contrast-enhanced study by multidetector row computed tomography revealed a well-enhanced 5 x 5 mm mass in the head of the pancreas with dilatation of the main pancreatic duct in the body and tail. On endoscopic retrograde pancreatography, obstruction of the main pancreatic duct in the head of the pancreas was noted. Pancreatic juice cytology was nondiagnostic. Endoscopic ultrasonography demonstrated a well-defined hypoechoic mass, about 5 mm in size, with distal main pancreatic duct dilatation. The patient underwent elective pylorus-preserving pancreaticoduodenectomy. Pathological examination revealed a well-differentiated endocrine tumor of the pancreas of uncertain behavior, 5 mm in size. Immunohistochemically, the tumor was diffusely positive for chromogranin A and synaptophysin, and focally it was positive for insulin, glucagon, and CA19-9; it was negative for gastrin. The final diagnosis was main pancreatic duct obstruction secondary to a nonfunctioning endocrine tumor of the pancreas of uncertain behavior. Of note, a small nonfunctioning endocrine tumor of the pancreas is important in the differential diagnosis of main pancreatic duct obstruction demonstrated by radiographic examinations.
authors.affiliation: Department of Surgery, Division of Clinical Medical Science, Graduate School of Biochemical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan. umk@hiroshima-u.ac.jp
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Uemura
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Murakami
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hayashidani
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sudo
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hashimoto
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ohge
authors.forename: Tamito
authors.initials: T
authors.lastname: Sasaki
authors.forename: Koji
authors.initials: K
authors.lastname: Arihiro
authors.forename: Taijiro
authors.initials: T
authors.lastname: Sueda
mesh_terms: D000368:Aged; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000379:methods; D003287:Contrast Media / Q000494:pharmacology; D003937:Diagnosis, Differential; D004701:Endocrine Gland Neoplasms / Q000150:complications* / Q000601:surgery; D004724:Endoscopy; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D019394:Ki-67 Antigen / Q000096:biosynthesis; D008297:Male; D010183:Pancreatic Ducts / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D010190:Pancreatic Neoplasms / Q000150:complications* / Q000601:surgery; D010195:Pancreatitis / Q000150:complications; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D019394:Ki-67 Antigen