ICD-10 D04.21
Billable / SpecificCarcinoma in situ of skin of right ear and external auricular canal
About ICD-10-CM D04.21
ICD-10-CM code D04.21 represents Carcinoma in situ of skin of right ear and external auricular canal. This is a billable/specific code in the Neoplasms chapter (block D04). The 2026 edition of ICD-10-CM D04.21 became effective on October 1, 2025.
Medicare LCD Coverage for D04.21
Local Coverage Determinations (LCDs) from CMS MACs that list D04.21 as a covered diagnosis.
Showing top 10 of 672 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing D04.21.
5 Medicare
CPT Codes Commonly Billed with D04.21
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 77336 CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
- 77370 CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
- 77439 CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
- 77436 CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
- 77437 CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
- 77285 CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
- 0394T CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
- 77280 CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
- G6001 CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
- 77300 CMS LCD: Billing and Coding: Superficial Radiation Therapy (SRT) for the Treatment of Nonmelanoma Skin Cancers (NMSC) CMS LCD
Convert D04.21 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 |
|---|---|---|
| D04.21 | 2322 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To D04.21
Other codes in section D00-D09 (In situ neoplasms).
ICD-10 D04.21, Billing FAQ
Is ICD-10 code D04.21 billable? +
Yes, D04.21 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What CPT codes are commonly billed with D04.21? +
Procedures frequently paired with D04.21 include: 77336, 77370, 77439, 77436, 77437.
What ICD-9 codes does D04.21 map to? +
Per CMS GEMs, D04.21 maps to ICD-9 codes: 2322. Useful for legacy data review and historical claim analysis.
Get the full PayerReady toolkit
Free access to CPT/ICD-10 lookup, denial appeals, fee comparator, and claim auditing with credentialing enrollment.
Start free →Run this code through our claim audit tool
Check NCCI bundling, MUE limits, and modifier logic before submission.
Try the auditor →Did this page help?
Quick signal so we know what to improve.
If you want a code reference page that doesn't exist yet, email coding@payerready.com.
Tell us what's missing or wrong: coding@payerready.com. We respond within 5 business days.
Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
Powered by 11K CPT · 98K ICD-10 · 860K MPFS rates · 4.5M NCCI edits · 9.5M NPIs. Our data methodology · About our coding team