C50.A0: Malignant inflammatory neoplasm of unspecified breast

New code · FY2026

Billable: use this code on claims.

• New code, effective October 1, 2025 (FY2026).

Code breakdown

Coding notes

Inclusion terms (from C50.A)

• Inflammatory breast cancer (IBC)

Includes (from C50)

• connective tissue of breast
• Paget's disease of breast
• Paget's disease of nipple

Excludes1 (from C50)

• skin of breast (C44.501, C44.511, C44.521, C44.591)

Use additional code (from C50)

• code to identify estrogen, and other hormones and factors receptor status (Z17.-)

Medicare coverage

C50.A0 is listed as a covered diagnosis in 14 Medicare billing and coding articles:

• A54338 Billing and Coding: MolDX: Germline testing for use of PARP inhibitors
• A55224 Billing and Coding: MolDX: Germline testing for use of PARP inhibitors
• A55294 Billing and Coding: MolDX: Germline testing for use of PARP inhibitors
• A56542 Billing and Coding: BRCA1 and BRCA2 Genetic Testing
• A56695 Billing and Coding: Implantable Infusion Pump
• A56748 Billing and Coding: White Cell Colony Stimulating Factors
• A56827 Billing and Coding: Proton Beam Therapy
• A57449 Billing and Coding: BRCA1 and BRCA2 Genetic Testing
• A58652 Billing and Coding: MolDX: Lab-Developed Tests for Inherited Cancer Syndromes in Patients with Cancer
• A58679 Billing and Coding: MolDX: Lab-Developed Tests for Inherited Cancer Syndromes in Patients with Cancer

…and 4 more. Check the coverage tool for your CPT code.

Check this code

• Code search: full entry and nearby codes
• Excludes checker: can it be billed with another code?
• Coverage checker: is it covered for your CPT code?

All FY2026 ICD-10-CM changes

ICD-10-CM codes and descriptions are from the CMS and NCHS code files. Coverage is from the CMS Medicare Coverage Database billing and coding articles.