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Confirmed germline pathogenic / likely-pathogenic monoallelic variant in CHEK2. Most comm...

Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.

IDRF-CHEK2-CONFIRMED-CARRIER
TypeRed flag
Statusreviewed 2026-05-19 | pending_clinical_signoff
DiseasesDIS-BREAST DIS-CRC DIS-PROSTATE
SourcesSRC-NCCN-BREAST-2025 SRC-NCCN-GENETIC-FAMILIAL-BREAST-OVARIAN-2025 SRC-NCCN-GENETIC-FAMILIAL-CRC-2025

Red Flag Origin

DefinitionConfirmed germline pathogenic / likely-pathogenic monoallelic variant in CHEK2. Most common population variant is c.1100delC truncating loss-of-function (~1.5% European population frequency); other pathogenic variants include c.444+1G>A (splice), p.Ile157Thr (missense with modest effect), and large deletions. Heterozygous CHEK2 carriers have moderate-penetrance breast cancer risk (RR ~2.0-3.0; lifetime ~20-30% for truncating variants, lower for missense), modest CRC risk (RR ~1.5-2.0; lifetime ~5-10% over baseline), prostate cancer (RR ~2-3 with high-grade enrichment for c.1100delC), thyroid cancer (smaller signal). Most common moderate-penetrance variant in multi- gene panels among European-ancestry cohorts. Patient has confirmed positive germline test; no current personal cancer diagnosis in the carrier being assessed. Prevention-persona RedFlag (§20, v0.3 moderate-penetrance breast g...
Clinical directioninvestigate
Categoryother

Trigger Logic

{
  "any_of": [
    {
      "finding": "germline_chek2_pathogenic_variant_confirmed",
      "value": true
    },
    {
      "finding": "germline_chek2_1100delc_confirmed",
      "value": true
    },
    {
      "finding": "germline_chek2_likely_pathogenic_variant",
      "value": true
    }
  ],
  "type": "lab_value"
}

Notes

Prevention-persona RedFlag for CHEK2 heterozygous carriers. Risk estimates vary substantially by variant: truncating > splice > missense. Engine routes to enhanced breast surveillance (annual mammography from age 40 + MRI consideration), modestly tightened CRC screening (colonoscopy from age 40 with q5y interval per NCCN), and prostate awareness from age 40-45 for males with c.1100delC. STUB pending two-Co-Lead signoff per CHARTER §6.1 dev-mode.

Used By

Indications

Red flag