PT - JOURNAL ARTICLE AU - Fang, D C AU - Jass, J R AU - Wang, D X AU - Zhou, X D AU - Luo, Y H AU - Young, J TI - Infrequent loss of heterozygosity of APC/MCC and DCC genes in gastric cancer showing DNA microsatellite instability. AID - 10.1136/jcp.52.7.504 DP - 1999 Jul 01 TA - Journal of Clinical Pathology PG - 504--508 VI - 52 IP - 7 4099 - http://jcp.bmj.com/content/52/7/504.short 4100 - http://jcp.bmj.com/content/52/7/504.full SO - J Clin Pathol1999 Jul 01; 52 AB - AIM: To investigate the role of DNA microsatellite instability (MSI) in gastric carcinogenesis by studying associations between MSI status, clinicopathological features, and loss of genetic loci. METHODS: Six microsatellite loci and loss of heterozygosity at APC, DCC, and MCC were analysed by polymerase chain reaction based methods in 53 cases of advanced gastric cancer. RESULTS: MSI was observed in 32.1% of gastric carcinomas (17/53) and 20% of foci of intestinal metaplasia (3/15). Seven gastric carcinomas (13.7%) were MSI-high (MSI-H) (three loci or more) and 10 (18.9%) were MSI-low (MSI-L) (one or two loci). The frequency of MSI-H was higher in intestinal (25.0%) than in diffuse carcinomas (3.7%) (p < 0.05). None of the MSI-H tumours showed loss of heterozygosity at APC, MCC, or DCC loci. CONCLUSIONS: MSI may have an important and early role in a subset of gastric cancers, particularly the intestinal type. The MSI-H subset of gastric cancer has features in common with its colorectal counterpart, whereas MSI-L and microsatellite stable cancers appear to develop through the loss of heterozygosity pathway.