Pathology/Lab Coding Alert

Question: We have a dermatology clinic client for whom we occasionally examine frozen sections from a skin biopsy specimen for a patient who then proceeds to Mohs micrographic surgery on the same day. Is there some way we can code these cases to avoid denials?

Texas Subscriber

Answer: Yes, you can use a modifier to ensure that you get paid for these services.

The problem denial for a case like this stems from the fact that the National Correct Coding Initiative (NCCI) edits bundles frozen section evaluation codes 88331-+88332 (Pathology consultation during surgery, … tissue block with frozen section(s) …) with Mohs micrographic surgery codes 17311-+17315 (Mohs micrographic technique, including removal of all gross tumor, surgical excision of tissue specimens, mapping, color coding of specimens, microscopic examination of specimens by the surgeon, and histopathologic preparation including routine stain(s) (eg, hematoxylin and eosin, toluidine blue) … ). That’s because the Mohs procedure includes histopathologic preparation and microscopic exam by the surgeon, who also functions as the pathologist in these cases.

But if your pathologist examines a specimen from a separate biopsy, not from the Mohs procedure, you may separately code that work. To override the NCCI edit for these codes, you’ll need to use an appropriate modifier such as 59 (Distinct procedural service) or a more-specific modifier such as XE (Separate encounter, a service that is distinct because it occurred during a separate encounter) or XU (Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service).