Family pedigree pattern suggestive of germline NF1 carrier state in an asymptomatic indiv...

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

ID	`RF-NF1-FAMILY-HISTORY-SUSPICION`
Type	Red flag
Status	reviewed 2026-05-19 \| pending_clinical_signoff
Diseases	`DIS-BREAST` `DIS-GLIOMA-LOW-GRADE` `DIS-SOFT-TISSUE-SARCOMA`
Sources	`SRC-NCCN-BREAST-2025` `SRC-NCCN-CNS-2025` `SRC-NCCN-GENETIC-FAMILIAL-BREAST-OVARIAN-2025`

Red Flag Origin

Definition	Family pedigree pattern suggestive of germline NF1 carrier state in an asymptomatic individual who has NOT yet had germline NF1 sequencing or who does NOT independently meet NIH/Bethesda clinical diagnostic criteria for neurofibromatosis type 1 (full- criteria-met individuals route to the confirmed-carrier RF). NF1 is autosomal-dominant with ~1 in 3000 prevalence — most common single-gene cancer-predisposition syndrome. Triggers include any of (a) first-degree relative with a confirmed NF1 pathogenic / likely-pathogenic variant (carrier-by-descent at-risk individual); (b) first-degree relative with full NIH-criteria-met clinical NF1 diagnosis (cutaneous café-au-lait pattern + neurofibromas) but no confirmatory genetic testing performed on the at-risk individual; (c) family-history pattern of childhood optic pathway glioma in one or more first/second-degree relatives — strongly suggestiv...
Clinical direction	investigate
Category	other

Trigger Logic

{
  "any_of": [
    {
      "finding": "family_nf1_known_pathogenic_variant_fdr",
      "value": true
    },
    {
      "finding": "family_first_degree_relative_with_clinical_nf1_diagnosis",
      "value": true
    },
    {
      "finding": "family_childhood_optic_pathway_glioma",
      "value": true
    },
    {
      "finding": "family_mpnst_in_relatives",
      "value": true
    }
  ],
  "type": "lab_value"
}

Notes

v0.3 Wave M suspicion variant — pre-testing family-history- suspicion counterpart to RF-NF1-CONFIRMED-CARRIER. Fires when family pedigree pattern suggests NF1 carrier state but the at- risk individual has not yet had germline NF1 sequencing AND does not independently meet ≥2 NIH/Bethesda clinical diagnostic criteria. Distinct trigger findings from the confirmed-carrier RF — the confirmed-carrier RF fires on `germline_nf1_pathogenic_ variant_confirmed`, `nih_nf1_clinical_diagnostic_criteria_met`, or `germline_nf1_likely_pathogenic_variant`; this suspicion RF fires on family-history-only findings. NF1 has an important pediatric dimension — at-risk children should have annual clinical evaluation by a pediatrician familiar with NF1 (cutaneous evaluation, neurologic exam, vision testing) before formal genetic testing. Genetic testing may be deferred until age 5-10 in asymptomatic at-risk children where the clinical picture remains equivocal — many NF1 features develop only in childhood and the diagnosis becomes clinically evident with age. Standard pathway includes referral to a specialty NF1 clinic (multidisciplinary — pediatric ophthalmology, genetics, neurology, dermatology) where a...

Used By

Indications

IND-NF1-SUSPICION-PREVENTION-EMPIRICAL-SURVEILLANCE - IND-NF1-SUSPICION-PREVENTION-EMPIRICAL-SURVEILLANCE
IND-NF1-SUSPICION-PREVENTION-TESTING - IND-NF1-SUSPICION-PREVENTION-TESTING