Pathology/Lab Coding Alert

Question: What CPT® codes should we report for breast specimen tests listed with the following results? tissue ER: positive (100% of the cells strongly positive) tissue PR: positive (rare focal weak positivity identified, greater than 20% of the cells) HER-2/neu overexpression: negative (0+/3+).

Tennessee Subscriber

Answer: You don't provide enough information to code with certainty. CPT® provides the following three codes that might describe immunohistochemistry (IHC) tests for estrogen receptor (ER), progesterone receptor (PR) and HER-2/neu for breast specimens:

• 88342 -- Immunohistochemistry [including tissue immunoperoxidase], each antibody
• 88360 -- Morphometric analysis, tumor immunohistochemistry (e.g., Her-2/neu, estrogen receptor/progesterone receptor), quantitative or semiquantitative, each antibody; manual
• 88361 -- ... using computer-assisted technology.

Because you performed three antibody tests -- ER, PR, and HER-2/neu -- you'll report three distinct codes for the service. But to choose the correct code for each test, you need to know whether the test is qualitative or quantitative/semiquantitative, and whether the lab platform is manual or automated.

Best guess: Because the ER/PR results express a percentage of stained cells, those tests would be quantitative or semiquantitative, meaning you'd report each test as 88360 or 88361. Because you don't know if the test is run on an automated platform, you can't choose between those two codes without more information.

The HER-2/neu results are even vaguer. Common HER-2/neu tests that use a reporting scale of 0 to 3+ involve counting cells as a component of the grading. If the scoring requires the pathologist to count cells to evaluate percentage of cell staining, 88360 or 88361 describe the procedure better than 88342. But some grading scales, especially for older IHC tests, may involve only a qualitative evaluation of staining intensity (such as 1+ to 4+), and may warrant 88342.