ICD-10 D33.9
Billable / Specific HCC v28: 12Benign neoplasm of central nervous system, unspecified
About ICD-10-CM D33.9
ICD-10-CM code D33.9 represents Benign neoplasm of central nervous system, unspecified. This is a billable/specific code in the Neoplasms chapter (block D33). The 2026 edition of ICD-10-CM D33.9 became effective on October 1, 2025.
Coding Tips for D33.9
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
D33.9 is a CMS-HCC v28 risk-adjustment code (category 12). To count for the patient Risk Adjustment Factor (RAF), document the diagnosis with MEAT language each calendar year: Monitored, Evaluated, Assessed, Treated. A diagnosis on the problem list alone does not satisfy CMS RADV audit standards. Include the diagnosis in the assessment with current status and current treatment plan.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under D33.9. Per CMS ICD-10-CM Tabular 2026.
- Benign neoplasm of nervous system (central) NOS
Medicare Advantage HCC Impact
Capture this diagnosis annually for accurate risk adjustment. Missed HCC captures are the #1 revenue leak in Medicare Advantage risk programs.
Medicare LCD Coverage for D33.9
Local Coverage Determinations (LCDs) from CMS MACs that list D33.9 as a covered diagnosis.
Showing top 10 of 81 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing D33.9.
1 Cigna
5 Medicare
CPT Codes Commonly Billed with D33.9
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
Convert D33.9 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| D33.9 | 2259 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To D33.9
Other codes in section D10-D36 (Benign neoplasms, except benign neuroendocrine tumors).
ICD-10 D33.9, Billing FAQ
Is ICD-10 code D33.9 billable? +
Yes, D33.9 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What other names or terms map to D33.9? +
ICD-10 D33.9 includes: Benign neoplasm of nervous system (central) NOS.
Does D33.9 affect Medicare Advantage HCC risk adjustment? +
Yes. D33.9 maps to CMS-HCC v28 category 12. Capture this diagnosis annually for accurate Medicare Advantage risk score.
What CPT codes are commonly billed with D33.9? +
Procedures frequently paired with D33.9 include: 95940, G0453, 95941.
What ICD-9 codes does D33.9 map to? +
Per CMS GEMs, D33.9 maps to ICD-9 codes: 2259. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on June 1, 2026.
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