Identifying Patients at Risk for HNPCC

Increasingly, direct genetic testing for germline mutations in MLH1, MSH2, and MSH6 is used to diagnose hereditary nonpolyposis colorectal cancer (HNPCC) in patients with a suggestive personal or family history. In general, the following "red flags" in a patient 's personal or family history should raise suspicion for HNPCC:
		Colorectal or endometrial cancer diagnosed prior to age 50
		Two or more HNPCC-related cancers in an individual or a family⁵¹

According to recent American Gastroenterological Association (AGA) guidelines,³² genetic testing for germline mutations in HNPCC-related genes is indicated for:
		Affected individuals from families meeting the Amsterdam Criteria
		Individuals with two HNPCC-related cancers (including synchronous/metachronous colorectal cancers)
		Individuals with colorectal cancer who have a first-degree relative with an HNPCC-related cancer (or colorectal adenoma) with at least one of the cancers diagnosed before age 50 (adenoma diagnosed before age 40)
		First-degree adult relatives of those with a known HNPCC mutation
		Colorectal cancer patients whose tumor specimens are microsatellite instability high (MSI-H).

Genetic testing will allow you to accurately identify patients with HNPCC and then adjust their medical management accordingly.

A genetic test for hereditary nonpolyposis colorectal cancer (HNPCC)