Pathology/Lab Coding Alert

Question: I'm confused about whether I can code 88342 per block of per specimen -- which is correct?

Answer: The answer may depend on the payer. Until Oct. 2009, payers agreed that the unit of service for a single immunostain (88342, Immunochemistry [including tissue immunoperoxidase], each antibody) was the specimen. In other words, regardless of the number of slides, levels, or blocks from a single specimen, you should code 88342 only once for a specific stain such as estrogen receptor (ER).

CCI game changer: In a departure from common coding practice, the Correct Coding Initiative (CCI) Policy Manual version 15.3, effective Oct. 1, 2009 states, "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)."

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 update: Entering the fray on this question, 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."

Ask payers: Based on the CCI manual, you should be able to code 88342 per stain per block for Medicare payers. You should check with other payers to determine their stance on the matter.