C44.521 vs C50.1
C44.521 (Squamous cell carcinoma of skin of breast) compared with C50.1 (Malignant neoplasm of central portion of breast), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. C50.1 carries an Excludes1 note covering C44.521: “skin of breast (C44.501, C44.511, C44.521, C44.591)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| C44.521Squamous cell carcinoma of skin of breast | C50.1Malignant neoplasm of central portion of breast | |
|---|---|---|
| Billing status | Billable | Non-billable header |
| Classification | C00-D49 — Neoplasms (C00-D49) | C00-D49 — Neoplasms (C00-D49) |
| Definition | Squamous cell carcinoma of skin of breast is a billable ICD-10-CM diagnosis code (C44.521). | Malignant neoplasm of central portion of breast is a non-billable ICD-10-CM category code (C50.1). |
| Includes | malignant neoplasm of sebaceous glands malignant neoplasm of sweat glands | connective tissue of breast Paget's disease of breast Paget's disease of nipple |
| Use additional code | — | code to identify estrogen, and other hormones and factors receptor status (Z17.-) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources