Undifferentiated giant cell type carcinoma of the gallbladder with sarcomatoid dedifferentiation: a case report and review of the literature.

Introduction: Undifferentiated gallbladder carcinoma is a rare entity. Among unusual types of undifferentiated gallbladder carcinoma, giant cell type carcinoma is infrequent and, moreover, very few cases of such neoplasms with osteoclast-like giant cells have been documented. We report a case of undifferentiated gallbladder carcinoma presenting an unusual immunophenotype that was shown to be of giant cell type with sarcomatoid dedifferentiation infiltrated by osteoclast-like multinucleated cells.

Gastrointestinal stromal tumors of the rectum: report of five cases.

We report on five patients (three males and two females), with a median age of 66.2 years (range, 58-73 years) who were admitted in our department from April 1998 until January 2004 with the diagnosis of rectal gastrointestinal stromal tumor (GIST). Their main symptoms were rectal bleeding, constipation and abdominal discomfort.

Collision tumour of the stomach with a cancer to cancer metastasis: a case report.

Introduction: Coexistence of a primary gastric lymphoma and a gastric adenocarcinoma is a rare event. The diagnosis is suspected after the pathologic examination of the endoscopic biopsies and definitely documented with the examination of the surgical specimen.

Case Presentation: We are presenting a rare case of a 77-year-old Greek man with epigastric pain of one and a half month duration, nausea, anorexia and weight loss.

BCL-2, p53 and HLA-DR antigen expression in surgically treated parotid cancer patients.

Our objective was to investigate the prognostic significance of bcl-2 protein, p53 protein and HLA-DR antigen expression in a group of surgically treated parotid cancer patients. We studied bcl-2, p53 and HLA-DR immunohistochemical expression in paraffin-embedded surgically removed tissue specimens derived from 26 patients with parotid cancer and 9 patients with Warthin parotid tumors operated between 2000 and 2006 at the Hippokration Hospital of Athens. The staining results were correlated with the patients' clinicopathological characteristics and clinical outcome.