Pathology/Lab Coding Alert

Question: When we perform tumor immunohistochemistry for ER/PR status for breast tissue, how should we report the procedure and the hormone status findings?

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Answer: To select the appropriate procedure code for breast tissue immunochemistry for estrogen receptor (ER) and/or progesterone receptor (PR) status, you need to know if the pathologist manually counts/estimates the number of stained cells on the slide, or if the procedure uses a computer to help assess the level of staining on the slides. Choose from the following codes:

• 88360 (Morphometric analysis, tumor immunohisto­chemistry [eg, Her-2/neu, estrogen receptor/ progesterone receptor], quantitative or semiquantitative, per specimen, each single antibody stain procedure; manual))
• 88361 (… using computer-assisted technology)

Dx: You can report ER positive results using Z17.0 (Estrogen receptor positive status (ER+)) and negative findings as Z17.1 (Estrogen receptor negative status (ER-)). ICD-10-CM currently doesn’t provide a specific code for PR status; however. when ICD-10-CM 2025 goes into effect on Oct. 1, 2024, you will have two new codes to indicate PR status:

• Z17.21 (Progesterone receptor positive status)
• Z17.22 (Progesterone receptor negative status)

More: The ICD-10-CM update will also include the following new codes that will make it easier to describe lab findings for human epidermal growth factor receptor 2 (HER-2) in association with ER/PR status. These updates will be significant for accurately reporting diagnoses that impact breast cancer treatment:

• Z17.31 (Human epidermal growth factor receptor 2 positive status)
• Z17.32 (Human epidermal growth factor receptor 2 negative status)
• Z17.410 (Hormone receptor positive with human epidermal growth factor receptor 2 positive status)
• Z17.411 (Hormone receptor positive with human epidermal growth factor receptor 2 negative status)
• Z17.420 (Hormone receptor negative with human epidermal growth factor receptor 2 positive status)
• Z17.421 (Hormone receptor negative with human epidermal growth factor receptor 2 negative status)

Code first: For any of the preceding findings, ICD-10-CM indicates that you must code first any malignant neoplasm, such as C50.- (Malignant neoplasm of breast).