ICD-10 Code C50.522 – Malignant neoplasm of lower-outer quadrant of left male breast (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C50.522 – Malignant neoplasm of lower-outer quadrant of left male breast
What it is
This code identifies a malignant tumor in the lower-outer quadrant of the left breast in a male patient. It specifies both the anatomic site and the patient sex.
Clinical signs
Typical findings include a palpable breast mass, nipple changes, skin dimpling, or localized pain, but clinical features vary; refer to documentation. Diagnosis is usually supported by imaging and pathology.
When to use this code
Use this code when the provider documents primary breast cancer in the lower-outer quadrant of the left breast and identifies the patient as male. It is appropriate for confirmed malignancy, including biopsy-proven or otherwise documented cases. If the quadrant or laterality is not stated, check documentation.
Do not use for
Do not use it for benign breast disease, carcinoma in situ, or unspecified breast site coding. Also avoid it when the record does not clearly support left-sided, lower-outer quadrant, male breast involvement.
Coding tip
Match the code to the exact site and laterality in the pathology or provider note before assigning it.