Pathology/Lab Coding Alert

Question: How should we code a breast biopsy specimen that the pathologist processes in three blocks labeled A:1, A:2 and A:3 with qualitative immunohistochemistry for estrogen receptor and progesterone receptor on each block? Should we code the special stain for each block?

Illinois Subscriber

Answer: You should report the pathologist's examination of the breast biopsy as 88305 (Level IV, Surgical pathology, gross and microscopic examination; breast, biopsy, not requiring microscopic evaluation of surgical margins).

You should not code the estrogen receptor (ER) and progesterone receptor (PR) for each block. As with all special stains, the unit of service for immunohistochemistry (IHC) is the specimen, regardless of the number of blocks or slides that you stain.

In this case, however, you should charge more than one unit of the IHC stain code (88342, Immunohistochemistry [including tissue immunoperoxidase], each antibody). That's because the pathologist uses two separate stains -- ER and PR. For that reason, you should list 88342 x 2 in addition to the 88305 service.