title: Primary retroperitoneal acinar cell cystadenoma.
abstract: In this report, we describe a case of hitherto unreported primary retroperitoneal acinar cell cystadenoma that morphologically and immunophenotypically resembled pancreatic acinar cell cystadenoma. Pancreatic acinar cell cystadenoma is a very uncommon benign lesion characterized by acinar cell differentiation, the evidence of pancreatic exocrine enzyme production, and the absence of cellular atypia. Our case occurred in a 55-year-old woman presenting a 10-cm multilocular cystic lesion in the retroperitoneum thought to be a mucinous cystic neoplasm. At laparotomy, the cystic mass, which showed no connection with any organ, was completely resected with a clinical diagnosis of cystic lymphangioma. The diagnosis of retroperitoneal acinar cell cystadenoma was based on the recognition of morphological acinar differentiation, the immunohistochemical demonstration of the acinar marker trypsin, and the absence of cellular atypia. These peculiar features can be used in the differential diagnosis with all the other cystic lesions of the retroperitoneum.
authors.affiliation: Department of Pathology, S. Cuore Don Calabria Negrar 37024, Italy. anna.pesci@sacrocuore.it
authors.forename: Anna
authors.initials: A
authors.lastname: Pesci
authors.forename: Paola
authors.initials: P
authors.lastname: Castelli
authors.forename: Enrico
authors.initials: E
authors.lastname: Facci
authors.forename: Luigi
authors.initials: L
authors.lastname: Romano
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Zamboni
mesh_terms: D061354:Acinar Cells / Q000378:metabolism / Q000473:pathology*; D014408:Biomarkers, Tumor / Q000378:metabolism; D003537:Cystadenoma / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D003937:Diagnosis, Differential; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D018191:Lymphangioma, Cystic / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D008875:Middle Aged; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D016896:Treatment Outcome; D014357:Trypsin / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D014357:Trypsin