ICD-10 Code C50.929 – Malignant neoplasm of unspecified site of unspecified male breast (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C50.929 – Malignant neoplasm of unspecified site of unspecified male breast
What it is
This code identifies a malignant breast tumor in a male patient when the exact site is not documented. Use it when the record confirms breast cancer but does not specify the quadrant or other location.
Clinical signs
Clinical features vary; refer to documentation. Breast cancer in men may present as a palpable breast mass, nipple changes, discharge, or skin or tissue distortion, but coding should follow the documented diagnosis.
When to use this code
Use C50.929 when the provider documents primary malignant neoplasm of the male breast and the site is unspecified. This is appropriate for pathology, oncology, or discharge records that confirm malignancy without a more precise breast location. If later documentation identifies a specific site, code that more specific diagnosis instead.
Do not use for
Do not use this code for female breast cancer or for benign, in situ, or metastatic disease without documentation supporting a primary male breast malignancy. Check documentation if the site is known.
Coding tip
Query the provider when the record says “male breast cancer” but omits the exact site, because laterality and location may support a more specific code.