Lobular carcinoma in situ of left breast

This code identifies the presence of abnormal cell growth confined to the lobules of the left breast, which is considered a non-invasive precursor to invasive lobular carcinoma. It signifies a high-risk lesion that has not spread beyond the lobule's basement membrane.

Apply this code when documentation explicitly states a diagnosis of lobular carcinoma in situ (LCIS) affecting the left breast. This diagnosis is typically established via biopsy or surgical pathology reports.

• Ensure the laterality (left breast) is clearly documented.
• Do not confuse with invasive lobular carcinoma (C50.-) or ductal carcinoma in situ (D05.1-).
• Code only confirmed diagnoses; do not use for suspected or rule-out conditions.