ICD-10 Code C50.521 – Malignant neoplasm of lower-outer quadrant of right male breast (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C50.521 – Malignant neoplasm of lower-outer quadrant of right male breast
What it is
This code identifies a malignant tumor in the lower-outer quadrant of the right breast in a male patient. Use it when documentation specifies both the breast quadrant and male sex.
Clinical signs
Clinical features may include a palpable breast mass, nipple changes, skin dimpling, or local tenderness. Clinical features vary; refer to documentation.
When to use this code
Use C50.521 when the provider documents primary breast cancer in the lower-outer quadrant of the right male breast. It is also appropriate when imaging, biopsy, or pathology clearly localizes the malignancy to that quadrant. Check documentation if the site is described differently or only as breast cancer.
Do not use for
Do not use this code for benign breast disease, unspecified breast malignancy, or cancer in a different breast quadrant. Also avoid it if the record does not confirm the right male breast location.
Coding tip
Verify laterality, quadrant, and male sex in the report before assigning C50.521.