Q85.01 ICD-10-CM Code: Neurofibromatosis, type 1
HCC Buddy Code Card
Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.
FY 2026 Apr update / Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0) / Other congenital malformations (Q80-Q89)
Q85.01
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidanceNeurofibromatosis, type 1
Neurofibromatosis type 1 is an inherited genetic disorder causing multiple benign tumors to grow along nerves, often with skin changes and bone abnormalities.
Buddy Insight
Neurofibromatosis type 1 is the most common form, affecting 1 in 3,000 people and carrying significant cancer risk including malignant peripheral nerve sheath tumors, requiring lifelong surveillance and multidisciplinary management.
CMS-HCC V28
MappedHCC 23
RAF 0.251
CMS-HCC V24
MappedHCC 12
RAF 0.150
ACA/HHS
00
RAF 0
ESRD/PACE
MappedHCC 12
RAF 0.0
RXHCC
00
RAF 0
Code Trumping
Basket needed
Code Book Path
Inclusion Terms
Official- Von Recklinghausen disease
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for Q85.01 in this effective period.
Related Child Codes
Includes
OfficialICD-10-CM does not list Includes notes for Q85.01 in this effective period.
Excludes 1
OfficialICD-10-CM does not list Excludes 1 notes for Q85.01 in this effective period.
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for Q85.01 in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for Q85.01 in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for Q85.01 in this effective period.
Buddy Documentation Tip
MEAT Support
Audit Caution
Common Mistakes
Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.
Is Q85.01 an HCC code?
Yes. Q85.01 maps to Melanoma and Other Skin Cancers under the CMS-HCC V28 risk adjustment model (and Breast, Prostate, and Other Cancers and Tumors under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for Q85.01
For Q85.01to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed Q85.01 during that encounter, not just copy-forwarded from a problem list.
What This Code Means
Q85.01 is the ICD-10-CM diagnosis code for neurofibromatosis, type 1. Neurofibromatosis type 1 is an inherited genetic disorder causing multiple benign tumors to grow along nerves, often with skin changes and bone abnormalities. Q85.01 sits in the ICD-10-CM chapter for congenital malformations, deformations and chromosomal abnormalities (q00-qa0), within the section covering other congenital malformations (q80-q89).
Under the CMS-HCC V28 risk adjustment model, Q85.01 maps to Melanoma and Other Skin Cancers (HCC 23) with a community, non-dual, aged base RAF weight of 0.251. Under the older CMS-HCC V24 model, Q85.01 maps to Breast, Prostate, and Other Cancers and Tumors (HCC 12) with a community, non-dual, aged base RAF weight of 0.150. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
NF1 is the most common type; document specific manifestations such as café-au-lait spots, optic nerve involvement, or skeletal abnormalities. Because Q85.01 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for Q85.01 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •NF1 is the most common type; document specific manifestations such as café-au-lait spots, optic nerve involvement, or skeletal abnormalities
- •Consider coding associated complications separately (e.g., malignant peripheral nerve sheath tumors if present)
Clinical Significance
Neurofibromatosis type 1 is the most common form, affecting 1 in 3,000 people and carrying significant cancer risk including malignant peripheral nerve sheath tumors, requiring lifelong surveillance and multidisciplinary management. The condition has high penetrance with variable expression, necessitating individualized care approaches and genetic counseling for families.
Documentation Requirements
- ✓Two or more NF1 diagnostic criteria met
- ✓Multiple café-au-lait spots with specific size criteria
- ✓Two or more neurofibromas or one plexiform neurofibroma
- ✓Freckling in axillary or inguinal regions
- ✓Optic glioma documentation
- ✓Distinctive osseous lesions
- ✓First-degree relative with NF1
- ✓Genetic testing results when available