Intraductal papillary neoplasms of the bile duct (IPNB) is the collective term used to refer to papillary bile duct tumors, mucin producing bile duct tumors, and cystic bile duct tumors. Pathologically, these tumors may be considered a highly differentiated adenocarcinoma or a tumor of borderline malignant potential. IPNB is classified into one of four variants based on cell differentiation.
View Article and Find Full Text PDFBackground: Low-grade cribriform cystadenocarcinomas (LGCCC) are rare salivary gland tumors, classified into a variant of cystadenocarcinoma by the 2005 WHO classification. All previously reported cases arose from parotid glands, except for a case from a minor salivary gland. We report here for the first time a case of LGCCC arising from the submandibular gland.
View Article and Find Full Text PDFDuring a routine health examination, a 50-year-old man was found to have an elevated lesion at the esophagogastric junction. Poorly differentiated adenocarcinoma was diagnosed from the biopsy findings. Computed tomography showed metastases in the mediastinal, intra-abdominal, and paraaortic lymph nodes.
View Article and Find Full Text PDFSecondary resistance of gastrointestinal stromal tumors (GISTs) to tyrosine kinase inhibitors occurs after several years' administration. However, the mechanism of resistance has not been fully clarified. In this study, we analyzed the genotypes and the histologic and immunohistochemical phenotypes of metastatic GISTs with and without imatinib treatment, and clarified the pleomorphic nature of metastatic GISTs.
View Article and Find Full Text PDFProgressive transformation of germinal center (PTGC) usually affects the peripheral lymph nodes. Little is known about the extranodal PTGC. To clarify the clinicopathological and molecular findings of extranodal PTGC, we studied 14 such cases.
View Article and Find Full Text PDFBackground: Esophageal carcinosarcoma is a very rare neoplasm and its clinicopathological characteristics and the prognostic factors that influence the clinical outcome of the patient remain a matter of controversy.
Patients And Methods: Twenty patients with esophageal carcinosarcoma were referred to our institutions. Tissue blocks were reviewed and sections containing both carcinomatous and sarcomatous components were stained for epithelial and mesenchymal markers and a proliferating cell marker.
To identify additional alterations to c-kit or platelet-derived growth factor receptor alpha (PDGFRA) genes in gastrointestinal stromal tumors (GIST), we investigated the methylation status of nine known methylation-sensitive CpG islands (p15, p16, p73, 0-6-methylguanine-DNA methyltransferase, E-cadherin, mutL homolog 1, colon cancer nonpolyposis type 2 (escherichia), methylated in tumors [MINT]1, MINT2, and MINT31), and compared the results with the malignant potential and gain-of-function mutation types of GIST. Thirty-five GIST (c-kit mutations in 25 cases, PDGFRA mutations in seven cases, and lacking either mutation in three cases) were subjected to methylation-specific polymerase chain reaction to detect the methylation status of the nine methylation-sensitive CpG islands. Aberrant DNA methylation of these loci was found in 94% of all GIST.
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