A novel case of rhabdoid colon carcinoma associated with a positive CpG island methylator phenotype and BRAF mutation.

Autor: Pancione M; Department of Biological and Environmental Sciences, University of Sannio, 82100 Benevento, Italy., Di Blasi A, Sabatino L, Fucci A, Dalena AM, Palombi N, Carotenuto P, Aquino G, Daniele B, Normanno N, Colantuoni V
Jazyk: angličtina
Zdroj: Human pathology [Hum Pathol] 2011 Jul; Vol. 42 (7), pp. 1047-52. Date of Electronic Publication: 2011 Feb 11.
DOI: 10.1016/j.humpath.2010.10.016
Abstrakt: Colon carcinoma with rhabdoid characteristics is a rare, malignant tumor whose molecular alterations have not been clarified yet. We report a novel case of a colon adenocarcinoma with rhabdoid features in a 71-year-old woman, localized to the right colon and associated with local lymph node and liver metastasis. The patient died within 8 months from surgery despite target chemotherapy. The tumor was enriched in cells with a typical rhabdoid-type morphology displaying a marked and diffuse vimentin staining. Cells were also positive for epidermal growth factor receptor (EGFR), p53, Ki67, and β-catenin and negative for cytokeratin 20/cytokeratin 7, E-cadherin, and CDX2. Remarkably, the promoter regions of 4 of 5 specific genes that define the so-called "CpG island methylator phenotype," including mutL homolog 1 (MLH1), were methylated. Consistently, microsatellite instability was detected. A BRAF V600E mutation and no KRAS mutations were identified. Finally, 4 tumor suppressor gene promoters CDH1, CDKN1B, CDKN1C, and MGMT were not methylated. This is the first case of a colorectal carcinoma with rhabdoid features, "CpG island methylator phenotype," high microsatellite instability associated with a BRAF mutation, and patient poorer outcome.
(Copyright © 2011 Elsevier Inc. All rights reserved.)
Databáze: MEDLINE