Amsterdam II Criteria (Lynch Syndrome)
The Amsterdam II criteria (Vasen and colleagues 1999) identify families that may have Lynch syndrome, also called hereditary non-polyposis colorectal cancer.
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Example
- At least 3 relatives with a cancer in the Amsterdam II spectrum
- Yes
- One of them is a FIRST-DEGREE relative of the other two
- Yes
- At least 2 successive generations affected
- Yes
- At least one diagnosed before age 50
- Yes
- Familial adenomatous polyposis excluded in the colorectal cases
- Yes
- Tumors verified by pathological examination
- Yes
- Are all three cancers colorectal?
- No
Result: Meets Amsterdam II
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What the result means
- Mnemonic
- "3-2-1" covers only THREE of the six. It omits the FIRST-DEGREE relationship, FAP exclusion, and pathological verification.
- The trap
- Three affected COUSINS satisfy "3" and fail the criteria - one of the three must be first-degree to the other two.
- Spectrum
- CLOSED: colorectal, endometrium, small intestine, ureter, renal pelvis. Any other cancer contributes NOTHING to the count.
- Amsterdam I
- Counted COLORECTAL ONLY. A family whose three cancers include an endometrial one meets II and fails I.
- Negative
- NOT evidence against Lynch syndrome. Bethesda exists because these criteria are TOO STRICT. Do not withhold MMR IHC, MSI or germline testing.
- Accuracy
- Sensitivity and specificity DELIBERATELY WITHHELD - always null. The quoted figures were single-sourced.
- Scope
- FAMILY-HISTORY criteria. Do not diagnose Lynch syndrome (a germline diagnosis), identify a gene, or set surveillance.
What you enter
- At least 3 relatives with a cancer in the Amsterdam II spectrum.
- One of them is a FIRST-DEGREE relative of the other two.
- At least 2 successive generations affected.
- At least one diagnosed before age 50.
- Familial adenomatous polyposis excluded in the colorectal cases.
- Tumors verified by pathological examination.
- Are all three cancers colorectal?
Full field descriptions
- At least 3 relatives with a cancer in the Amsterdam II spectrum. Covered by the "3-2-1" mnemonic.
- One of them is a FIRST-DEGREE relative of the other two. NOT covered by the "3-2-1" mnemonic - this is one of the three requirements the mnemonic omits.
- At least 2 successive generations affected. Covered by the "3-2-1" mnemonic.
- At least one diagnosed before age 50. Covered by the "3-2-1" mnemonic.
- Familial adenomatous polyposis excluded in the colorectal cases. NOT covered by the "3-2-1" mnemonic - this is one of the three requirements the mnemonic omits.
- Tumors verified by pathological examination. NOT covered by the "3-2-1" mnemonic - this is one of the three requirements the mnemonic omits.
- Are all three cancers colorectal? Used only for the Amsterdam I comparison, whose spectrum was colorectal cancer only.
How this is calculated
- Rule
- ALL SIX requirements must be met. A CONJUNCTION, not a count - 5 of 6 FAILS and is not a near miss.
Vasen HFA, Watson P, Mecklin JP, Lynch HT. New clinical criteria for HNPCC (Lynch syndrome) proposed by the International Collaborative Group on HNPCC. Gastroenterology. 1999;116(6):1453-1456. Amsterdam I: Vasen HFA, et al. Dis Colon Rectum. 1991;34(5):424-425. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.