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Immunohistochemistry for Microscopic Evaluation of Breast Cancer
Blue Cross & Blue Shield of Mississippi·MS · Pathology, Oncology, General Surgery·Medical Policy
Effective date
Oct 1, 2025
We identified it
Jun 20, 2026
Summary
This is an established policy for immunohistochemistry (IHC) stains in breast cancer diagnosis that was reviewed on 12/06/2024 with no changes, and will have new ICD-10 codes added effective 10/01/2025. The policy defines coverage for ER, PR, and Her2 testing for invasive breast cancer and limited ER testing for ductal in-situ cancer.
Action Required
By October 1, 2025: Billing team must update coding system to include new ICD-10 diagnosis codes C50.A0, C50.A1, and C50.A2 for breast cancer cases. Verify these codes are available in billing software and encounter forms for pathology and oncology services.