| Amsterdam Criteria (1991) |
| 1. Three of more relatives, of whom two are first-degree relative of the third, with documented colorectal cancer |
| 2. Cancer occurring across two or more generations |
| 3. One or more cancers diagnosed before age 50 |
| 4. Familial adenomatous polyposis excluded |
| Bethesda Guidelines (1997) |
| 1. Individuals who meet the Amsterdam criteria |
| 2. Individual with two HNPCC-related cancers (synchronous/metachronous colorectal cancers or extracolonic cancers) |
| 3. Individuals with colorectal cancer and a first-degree relative with |
| a. Colorectal cancer diagnosed before age 45 or |
| b. HNPCC-related extracolonic cancer diagnosed before age 45 or |