The Amsterdam criteria are a set of guidelines used by practitioners to determine if a family is at risk of Hereditary Nonpolyposis Colorectal Cancer (HNPCC), also known as Lynch syndrome. These guidelines were originally developed in 1990 in Amsterdam, and were revised in 1999 in light of new information about genetics. The second set of criteria are sometimes referred to as Amsterdam II to differentiate them from the earlier recommendations. Genetic counselors and other medical professionals may consider these when evaluating a family with a history of colorectal and related cancers.
Under the original Amsterdam criteria, patients had to have three relatives with a history of colorectal cancer, and at least one of them had to be a first degree relative. This was later revised to include related cancers, like growths in the small bowel, renal pelvis, and endometrium. The cancers need to be confirmed with evaluation in a pathology lab, and doctors also need to exclude a condition called familial adenomatous polyposis, which can cause growths in the gut.
Additionally, the cancers need to span two or more generations, and at least one of them must have been diagnosed before age 50. Histories that meet these guidelines can indicate that a person could develop HNPCC, which might indicate a need for more aggressive screening and earlier interventions. The Amsterdam criteria create a useful guide for doctors making decisions about screening and treatment recommendations for their patients. After one person in a family meets the guidelines, others may want to consider evaluation as well.
In an additional adjustment to the original Amsterdam criteria, some practitioners argue that two incidences of cancer in a small family should qualify a patient for consideration. Genetic conditions can be harder to identify and track in a small family because there are fewer people in which they can manifest; a few random instances of cancer in these cases might not be so random when closely evaluated, as they could indicate that the family has a genetic predisposition to cancer. Patients undergoing review to see if they meet the Amsterdam criteria should also discuss other family cancers and genetic issues, as these may be important.
Doctors can also use the Bethesda guidelines, which work slightly differently, to evaluate a patient for the risk of HNPCC and to determine if tumors should undergo special testing. These guidelines can be used to determine if a patient should receive genetic testing to check for cancer risks. They can also provide information about whether more aggressive early screening would be advised to catch growths early.