What's the Difference in Her-2/neu Tests?
Published on Sat Oct 30, 2004
Some measure the gene, some measure the protein product
You see so many different Her-2/neu tests that it's hard to keep them straight. Find out if the lab is measuring "gene amplification" or "protein overexpression" to ensure that you'll never again be confused about which codes to use.
Why?: Doctors want to know about the Her-2/neu gene because elevated levels generally indicate a more aggressive tumor in breast cancer patients. The gene produces a specific protein, so pathologists can discover if a tumor has an increased amount of Her-2/neu either by measuring the gene itself or by measuring the protein it produces, says Laura Edgeworth, HTL, CPC, coding and audit specialist with Pathology Service Associates LLC (PSA), in Florence, S.C.
Use ISH Codes for Genes: Gene tests look for "amplification," or overproduction of the gene. One common test is fluorescence in situ hybridization (FISH). This test involves applying a fluorescent DNA "probe" to the tumor, which attaches to the specific gene (Her-2/neu) to determine if the tumor shows gene amplification.
You should report these tests using an ISH code, such as CPT 88367 (Morphometric analysis, in situ hybridization [quantitative or semiquantitative] each probe; using computer-assisted technology), Edgeworth says.
Look to ICH Codes for Proteins: Protein tests look for "overexpression," or overproduction of the gene's protein product. One common test is immunohistochemistry (IHC), which involves applying a special immunohistochemical stain to breast tumor tissue and quantifying the level of protein produced by the Her-2/neu gene.
You should report these tests using an IHC code such as 88360 (Morphometric analysis, tumor immunohistochemistry [e.g., Her-2/neu, estrogen receptor/progesterone receptor], quantitative or semiquantitative, each antibody; manual), Edgeworth says.