Pathology/Lab Coding Alert

Question: Our billing company told us that we can now charge a special antibody stain (88342) per slide instead of per specimen, as in the past. Is this correct?

Answer: No, you cannot charge 88342 (Immunohistochemistry [including tissue immunoperoxidase], each antibody) per slide. The misinformation probably stems from a recent change in Medicare policy that allows you to bill 88342 per block, not per specimen as you have in the past.

Because the 88342 code definition states "per antibody" and the surgical pathology unit of service is the specimen, long standing coding convention dictated that labs report only one unit of 88342 per specimen, per antibody, regardless of the number of blocks, slides, or "levels" involved.

CCI change: The Correct Coding Initiative (CCI) Policy Manual revised this understanding, at least for Medicare beneficiaries, with the following statement:

"If it is medically reasonable and necessary to perform the same stain on more than one specimen or more than one block of tissue from the same specimen, additional units of service may be reported for the additional specimen(s) or block(s)."

Don't code per level or slide: The manual goes on to clarify that if the lab cuts multiple levels from a single tissue block and stains each level with the same stain, you should not report additional units of service for the stain.

You should report only one unit of service "for the stain on multiple levels from the single tissue block," according to the CCI manual. Since the lab may prepare multiple slides from different levels, logic extends the restriction of not coding per level to not coding per slide.

AMA replies:The AMA published a CPT Assistant article in Oct. 2010 that enforces the pre-CCI coding position. The article states that you should report 88342 per antibody "no matter how many blocks are applied to a given specimen."

You may need to clarify with payers if you can report 88342 per specimen or per block for a single antibody stain. But under no circumstances should you report 88342 per slide.