ICD-10 Code C50.911 – Malignant neoplasm of unspecified site of right female breast (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C50.911 – Malignant neoplasm of unspecified site of right female breast
What it is
This code identifies a malignant tumor in the right female breast when the exact breast location is not specified in the record. Use it when documentation confirms cancer of the right breast but does not name a quadrant or other site.
Clinical signs
Clinical features vary; refer to documentation. Breast cancer may be described by a palpable mass, abnormal imaging, skin or nipple changes, or biopsy-confirmed malignancy.
When to use this code
Use C50.911 when the provider documents primary cancer of the right female breast and does not identify a more specific site. It is appropriate for final diagnoses, oncology follow-up notes, and pathology reports that confirm malignancy without localizing detail.
If later documentation names a specific quadrant or overlapping site, code to that more precise category instead. Check documentation for laterality and whether the tumor is primary, secondary, or in situ.
Do not use for
Do not use this code for left breast cancer, bilateral disease, or unspecified breast laterality. It also does not apply to benign breast masses or carcinoma in situ unless documentation specifically supports malignancy.
Coding tip
Verify both laterality and site detail before coding; if the record is vague, use the unspecified-site code only when the right breast is clearly documented.