Pathology/Lab Coding Alert

Question: Your answer to a recent bone-marrow biopsy coding question describes using CPT 88360 for a Her-2/neu test scored as 1+ using a semiquantitative scale [-Try Your Hand at This Bone Marrow Case,- Pathology/Lab Coding Alert April 2006]. Is that correct for all payers?

Mississippi Subscriber Answer: Although the code description for 88360 (Morphometric analysis, tumor immunohistochemistry [e.g., Her-2/neu, estrogen receptor/progesterone receptor], quantitative or semiquantitative, each antibody; manual) clearly includes semiquantitative tests, Medicare and some other payers expect you to report these tests with 88342 (Immunohistochemistry [including tissue immunoperoxidase], each antibody).
 
The confusion stems from a statement in the National Correct Coding Policy Manual to the effect that -immunohistochemistry reported with qualitative grading such as 1+ to 4+ should be reported as 88342.- The College of American Pathologists made a similar statement in the December 2004 CAP Today.
 
The problem with the statement is that a grading scale such as 1+ to 4+ is semiquantitative, not qualitative. The scoring systems generally require counting certain portions of the slide, estimating the overall percent staining, and selecting the appropriate -score- range for the estimated percentage.
 
Although Medicare requires 88342 for a semiquantitative test such as numerically scored Her-2/neu, you can make a strong case to other payers that the correct code is 88360 based on the code definition and the actual procedure.
 
For a complete discussion of this issue and our experts- advice, see -Use These 4 Tips for Reporting New and Revised IHC Codes- and -Be Sure You Reserve 88342 for Qualitative IHC- in the April 2005 Pathology/Lab Coding Alert.