D33.3 ICD-10-CM Code: Benign neoplasm of cranial nerves
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 / Neoplasms (C00-D49) / Benign neoplasms, except benign neuroendocrine tumors (D10-D36)
D33.3
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidanceBenign neoplasm of cranial nerves
A non-cancerous tumor that develops on one of the twelve pairs of nerves that originate from the brain.
Buddy Insight
Benign neoplasm of the cranial nerves most commonly represents vestibular schwannoma (acoustic neuroma) arising from the vestibulocochlear nerve (CN VIII), which accounts for 80-90% of benign cranial nerve tumors.
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
MappedHCC 22
RAF 0.0
Code Trumping
Basket needed
Code Book Path
Inclusion Terms
Official- Benign neoplasm of olfactory bulb
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for D33.3 in this effective period.
Related Child Codes
Includes
OfficialICD-10-CM does not list Includes notes for D33.3 in this effective period.
Excludes 1
Official- angioma (D18.0-)
- benign neoplasm of meninges (D32.-)
- benign neoplasm of peripheral nerves and autonomic nervous system (D36.1-)
- hemangioma (D18.0-)
- neurofibromatosis (Q85.0-)
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for D33.3 in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for D33.3 in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for D33.3 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 D33.3 an HCC code?
Yes. D33.3 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 D33.3
For D33.3to 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 D33.3 during that encounter, not just copy-forwarded from a problem list.
What This Code Means
D33.3 is the ICD-10-CM diagnosis code for benign neoplasm of cranial nerves. A non-cancerous tumor that develops on one of the twelve pairs of nerves that originate from the brain. D33.3 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering benign neoplasms, except benign neuroendocrine tumors (d10-d36).
Under the CMS-HCC V28 risk adjustment model, D33.3 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, D33.3 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.
Cranial nerves include the optic, oculomotor, trigeminal, facial, vestibulocochlear, and other nerves. Because D33.3 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 D33.3 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Cranial nerves include the optic, oculomotor, trigeminal, facial, vestibulocochlear, and other nerves
- •Document which specific cranial nerve is affected if possible for better clinical documentation
Clinical Significance
Benign neoplasm of the cranial nerves most commonly represents vestibular schwannoma (acoustic neuroma) arising from the vestibulocochlear nerve (CN VIII), which accounts for 80-90% of benign cranial nerve tumors. Other benign cranial nerve tumors include trigeminal schwannomas and facial nerve schwannomas. These tumors can cause hearing loss, tinnitus, facial weakness, and balance disturbances depending on the nerve involved.
Documentation Requirements
- ✓MRI with gadolinium enhancement documenting the cranial nerve tumor is the standard diagnostic study.
- ✓Identify the specific cranial nerve involved if possible.
- ✓Document tumor size, associated symptoms (hearing loss, tinnitus, facial paresis), audiometric findings, and the chosen management approach (observation, surgery, stereotactic radiosurgery).
- ✓If resected, include pathology confirming benign schwannoma.