NEW YORK (Reuters Health) -In primary esophageal squamous cell carcinoma, frequent microsatellite instability affecting two DNA mismatch repair genes is associated with extraesophageal primary carcinoma, according to a new study.
Microsatellite instability may be “predictive of another primary cancer in esophageal squamous cell carcinoma patients,” Dr. Masakazu Yashiro from Osaka City University Graduate School of Medicine in Japan told Reuters Health.
Patients with esophageal squamous cell carcinoma frequently develop other primary cancers, the researcher explained. In a prior study, 18% of 2991 patients with esophageal cancer developed cancer in another organ either synchronously or metachronously, with gastric cancer occurring most often followed by head and neck cancer and colorectal cancer.
Among 34 patients with esophageal carcinoma and other primary carcinomas in the current study, Dr. Yashiro’s team observed high frequency microsatellite instability in 15 patients (44.1%) but in only 6 (14.3%) of 42 patients with esophageal cancer alone (p < 0.01).
Twelve of 15 tumors with high frequency microsatellite instability (80%) showed loss of expression of either hMLH1 or hMSH2, two mismatch repair genes, the researcher reported in the March 10th International Journal of Cancer. Six of 9 tumors (66.7%) with reduced hMLH1 expression also displayed hypermethylation of the hMLH1 promotor region.
“In this study, carcinogenesis of esophageal carcinoma together with other primary carcinoma was closely associated with the microsatellite instability pathway because of mismatch repair protein deficiency,” Dr. Yashiro said.
The findings suggest that microsatellite instability might be a risk factor for another primary tumor in patients with esophageal squamous cell carcinoma, he concluded.
Source: Int J Cancer 2005;114:166-173. [ Google search on this article ]
MeSH Headings:Neoplasms: Neoplasms, Second Primary: Microsatellite Repeats: Tandem Repeat Sequences: DiseasesCopyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.
