Pathology/Lab Coding Alert

You Be The Coder:

Choose Flow Cytometry or Immunohistochemistry

Question: We are a cytogenetics and cancer center lab that frequently performs flow cytometry for bone marrow aspirates. Often, we require an immunohistochemistry stain on the associated bone marrow biopsy to reach a final diagnosis. Under what circumstances can we report both services, since the National Correct Coding Initiative edits prohibit reporting together 88342 and 88180?  

Colorado Subscriber

Answer: You are correct that the 2003 NCCI bundled 88342 (Immunohistochemistry [including tissue immunoperoxidase], each antibody) and 88180 (Flow cytometry; each cell surface, cytoplasmic or nuclear marker), which halted a common coding practice for some labs. CMS explained that, for a single specimen, it considered the two codes "duplicate tests" because the pathologist can generally establish the diagnosis using either method.

Further, CMS considers 88180 and 88342 duplicate tests even when performed on different specimens, if the specimens are similar. The agency gives the following examples of similar specimens:

1. blood and bone marrow
2. bone marrow aspiration and bone marrow biopsy
3. two separate lymph nodes
4. lymph node and other tissue with lymphoid infiltrate.

Although the list looks like bad news for your lab, which performs 88342 on the bone marrow biopsy and 88180 on the bone marrow aspiration, CMS does describe one circumstance that warrants reporting the two codes together for the same or similar specimens:

"The provider may report both CPT codes if both methods are required because the initial method is non-diagnostic or does not explain all the light microscopic findings. The provider can report both methods utilizing modifier -59 and document the need for both methods in the medical record."

So when the pathologist requires both methods to reach a final diagnosis, you may report 88180 and 88342 together, and override the NCCI edit by using modifier -59 (Distinct procedural service).

You can access this information in the National Correct Coding Policy Manual for Part B Medicare Carriers, Version 9.3, Chapter 10, at
http://www.cms.hhs.gov/physicians/cciedits/nccmanual.asp.