title: Peripheral primitive neuroectodermal tumor of the small bowel mesentery: a case showing perforation at onset.
abstract: A case of peripheral primitive neuroectodermal tumor of the small bowel mesentery with an uncommon clinical onset is reported. A 40-year-old man was admitted to hospital because of acute severe abdominal pain. Chest X-ray revealed a free air sign beneath the diaphragm. At emergency surgery a mass measuring 11.0 x 8.0 cm with perforation was located in the jejunal mesenteric region. Histologically the resected lesion consisted of sheets of undifferentiated small round cells forming abortive Homer Wright rosettes. Some spindle-shaped cells showed perivascular pseudorosettes. Immunohistochemical study revealed that the tumor cells expressed positivity against CD99 (MIC2), neuron-specific enolase, synaptophysin and vimentin. To the authors' knowledge this is the first documentation of peripheral primitive neuroectodermal tumor of the small bowel mesentery with perforation at onset.
authors.affiliation: Department of Pathology, Tottori University Hospital, Yonago, Japan. yhorie-ttr@umin.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Horie
authors.forename: M
authors.initials: M
authors.lastname: Kato
mesh_terms: D000006:Abdomen, Acute / Q000209:etiology / Q000473:pathology / Q000601:surgery; D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis; D017809:Fatal Outcome; D006801:Humans; D007150:Immunohistochemistry; D007416:Intestinal Perforation / Q000209:etiology / Q000473:pathology* / Q000601:surgery; D007421:Intestine, Small / Q000473:pathology* / Q000601:surgery; D008297:Male; D008643:Mesentery / Q000473:pathology*; D018241:Neuroectodermal Tumors, Primitive, Peripheral / Q000150:complications / Q000473:pathology* / Q000601:surgery; D010534:Peritoneal Neoplasms / Q000150:complications / Q000473:pathology* / Q000601:surgery
chemical_list: D014408:Biomarkers, Tumor