WHAT IS LYNCH SYNDROME?
Lynch syndrome (also known as Hereditary Non-Polyposis Colorectal Cancer, or HNPCC) is a hereditary cancer syndrome resulting from certain inherited changes, or mutations, in a class of genes known as the mismatch repair genes. When working properly, these genes help to correct certain types of errors in the body's genetic code that occasionally occur as part of the body's normal cellular processes. Individuals who are born with a copy of one of these genes that isn't working properly are at an increased risk for developing certain types of cancer. Experts estimate that as many as one in 500 people in the US are Lynch syndrome carriers.
People with Lynch syndrome are more likely to develop colon cancer in their lifetime, with colon cancer also tending to occur at an earlier age than in the general population. Women with this disorder also have a high risk of cancer of the endometrium (lining of the uterus) and ovaries. While rare even in people with Lynch syndrome, other cancers associated with this disorder include cancers of the stomach, small intestine, liver, gallbladder ducts, upper urinary tract, brain, skin, and prostate.
Although Lynch syndrome was originally described as not involving noncancerous (benign) growths (polyps) in the colon, people with Lynch syndrome may occasionally have colon polyps. Although the polyps do not occur in greater numbers than in the general population, they tend to occur at a younger age and are more likely to become cancerous. Polyps associated with Lynch syndrome have also been shown to move more quickly from the noncancerous polyp stage to cancer.
For more general information on hereditary cancer syndromes and the roles our genes play in cancer, start here.