Lynch syndrome

Lynch syndrome, also hereditary non-polyposis colorectal cancer syndrome (abbreviated HNPCC), is a constellation of clinical findings caused by a mutation in a mismatch repair gene, of which there are several.

As the name suggests, HNPCC is a form of inherited colorectal cancer that is not characterized by abundant intestinal polyps (non-polyposis), as in adenomatous polyposis coli.

Clinical

Divided into:

• Lynch syndrome I - colon cancer associated.
• Lynch syndrome II - non-colon cancer associated.

Associations

• Colorectal carcinoma.
• Non-endometrioid endometrial carcinoma.
• Stomach.
• Biliary tree.

Genes

• MSH2 gene.
• MLH1 gene.
• PMS2 gene.
• MSH6 gene.
• Others.

Special types

Muir-Torre syndrome

Muir-Torre syndrome is a subset of HNPCC that includes the presence of sebaceous adenomas. It is caused by mutations in MSH2 or MLH1.

See also

• GI polyps.
• Familial polyposis coli.