Table 2 Amsterdam I/II criteria and revised Bethesda guidelines for the selection of individuals with a higher risk of Lynch Syndrome

Amsterdam I criteria

There should be at least 3 relatives with colorectal cancer (CRC), and all the following criteria should be present:

- a first-degree relative of the other 2;

- cancer involving at 2 successive generations;

- at least one CRC diagnosed before the age of 50 years;

- familial adenomatous polyposis must be excluded

Amsterdam II criteria

Three or more relatives with histologically verified Lynch sindrome-related tumors (colorectal, endometrial, small bowel, ureter or renal pelvis) of which:

- a relative should be a first-degree relative of the other two;

- cancer involving at 2 successive generations;

- one or more cancers must be diagnosed before the age of 50 years;

- familial adenomatous polyposis should be excluded.

Revised Bethesda Guidelines

- Colorectal cancer diagnosed in a patient younger than 50 years;

- Presence of synchronous or metachronous colorectal or other LS-associated tumors, regardless of age;

- Colorectal cancer with MSI histology diagnosed in patients younger than 60 years;

- Colorectal cancer diagnosed in a patient with one or more first-degree relatives with LS-related cancer, with one of the tumors diagnosed under age 50 years;

- Colorectal cancer diagnosed in a patient with two or more first- or second-degree relatives with LS-related cancers regardless of age.