[Analysis of microsatellite alteration in colorectal cancer]

We investigated the possible correlation between the microsatellite alterations (replication error: RER, and loss of heterozygosity: LOH) and clinicopathologic factors and survival in colorectal cancer. A total of 78 colorectal cancers was examined for microsatellite alteration at three microsatellite loci containing D2S123, D18S58 and C117-703. RER is considered positive when at least one microsatellite locus is detected. RER was positive in 28.2%, and the respective positivity was 12.8%, 15.3% and 11.5%. The positivity of LOH was 6.4%, 10.3% and 19.2%, in that order. RER-positive cancers were more significantly found in the proximal colon than the distal colorectum. Node-negative colorectal cancers were more noted in RER (+)-positive cancers. Multivariate analysis showed that LOH in D18S58 locus and RER in CI17-703 locus were independent prognostic factors.