C50.4 (Malignant neoplasm of upper-outer quadrant of breast) compared with D05 (Carcinoma in situ of breast), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1. MedCoder-derived
Not coded here — these two are mutually exclusive.
“Paget's disease of breast or nipple (C50.-)”
An Excludes1 note means the two conditions cannot occur together, so the pair should not be reported for the same encounter. The sole exception is when the conditions are documented as unrelated to each other.
Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a
No — do not report together. D05 carries an Excludes1 note covering C50.4: “Paget's disease of breast or nipple (C50.-)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
| C50.4Malignant neoplasm of upper-outer quadrant of breast | D05Carcinoma in situ of breast | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | C00-D49 — Neoplasms (C00-D49) | C00-D49 — Neoplasms (C00-D49) |
| Definition | Malignant neoplasm of upper-outer quadrant of breast is a non-billable ICD-10-CM category code (C50.4). | Carcinoma in situ of breast is a non-billable ICD-10-CM category code (D05). |
| Includes | connective tissue of breast Paget's disease of breast Paget's disease of nipple | Bowen's disease erythroplasia grade III intraepithelial neoplasia Queyrat's erythroplasia |
| 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