title: Osteoclast-like giant cell tumour of the pancreas presenting as a pseudocyst-like lesion.
abstract: A 57-year-old male patient presented with a cystic lesion in the tail of the pancreas, which was considered to be a pseudocyst. He was treated by cystojejunostomy but one year later a tumour was found to have invaded the stomach and jejunum. This was an osteoclast-like giant cell tumour containing a small area of typical ductal adenocarcinoma. Immunohistochemical staining revealed that the pleomorphic tumour cells were positive for cytokeratin, epithelial membrane antigen, vimentin and the proliferation marker MIB-1. The osteoclast-like giant cells and some small histiocytic cells stained for leukocyte common antigen and histiocytic markers and were negative for MIB-1. At autopsy, tumour rests were found in the pancreas but there were no metastases. Osteoclast-like giant cell tumours of the pancreas may present as cystic lesions and should be included in the differential diagnosis of pseudocysts.
authors.affiliation: Department of Pathology, Hegau-Klinikum, Singen, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Oehler
authors.forename: M
authors.initials: M
authors.lastname: Jürs
authors.forename: G
authors.initials: G
authors.lastname: Klöppel
authors.forename: B
authors.initials: B
authors.lastname: Helpap
mesh_terms: D034961:Antigens, Nuclear; D014408:Biomarkers, Tumor / Q000032:analysis; D003937:Diagnosis, Differential; D017809:Fatal Outcome; D005870:Giant Cell Tumors / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D007583:Jejunum / Q000473:pathology; D007633:Keratins / Q000032:analysis; D019394:Ki-67 Antigen; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009687:Nuclear Proteins / Q000032:analysis; D010190:Pancreatic Neoplasms / Q000473:pathology* / Q000601:surgery; D010192:Pancreatic Pseudocyst / Q000473:pathology* / Q000601:surgery
chemical_list: D034961:Antigens, Nuclear; D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D009687:Nuclear Proteins; D007633:Keratins