Cancer Causes and Controls: abstract - Microsatellite instability and survival in rectal cancer (Lynch Syndrome)

"Abstract
Objective High levels of microsatellite instability (MSI-H) have been associated in many studies with improved prognosis in colon cancer. Very few studies have evaluated the effect of MSI-H on rectal cancer survival. We assessed MSI-H and other genetic and epigenetic changes on survival of 990 individuals diagnosed with first primary rectal cancer.
Conclusion The genetic and epigenetic characteristics of MSI-H rectal cancers suggest that they are enriched for Lynch-associated tumors; adverse prognosis associated with MSI-H in these tumors may reflect the relatively high frequency of Lynch-associated cancers and/or the effect of radiation or chemotherapy on Lynch-associated rectal cancers or MSI tumors in general."