Pathology/Lab Coding Alert

Question: Please help with coding for the following thyroid case:

Pathologist receives from surgery two FNA passes from a right thyroid nodule, evaluates each and reports back to surgeon — specimens adequate for evaluation. 

Pathologist evaluates thin-layer slides from each FNA pass, prepares and evaluates slides from the clot, and diagnoses thyroid peroxidase and CD56 immunostains on each specimen.

Texas Subscriber

Answer: The correct coding for the case is as follows:

• 88172 — Cytopathology, evaluation of fine needle aspirate; immediate cytohistologic study to determine adequacy for diagnosis, first evaluation episode, each site

• 88173 — Cytopathology, evaluation of fine needle aspirate; interpretation and report

• 88305 — Level IV - Surgical pathology, gross and microscopic examination … Cell block, any source

• 88342 x 2 — Immunohistochemistry or immunocytochemistry, per specimen; initial single antibody stain procedure

• +88341 x 2 — …each additional single antibody stain procedure (List separately in addition to code for primary procedure).

Not +88177: You may ask why the answer doesn’t include +88177 (… immediate cytohistologic study to determine adequacy for diagnosis, each separate additional evaluation episode, same site [List separately in addition to code for primary procedure]) for the adequacy check for the second FNA “pass” into the right thyroid nodule. CPT® changed the code definitions for 88172 and 88177 to specify that the unit of service for the codes is each “evaluation episode.” Because the pathologist evaluates aspirate from both passes at the same time and gives a single adequacy-check report to the surgeon, you should bill only for 88172.

Not 88112: Because the case involves “thin layer,” or liquid-based preparation slides, you may be tempted to add charge code 88112 (Cytopathology, selective cellular enhancement technique with interpretation [e.g., liquid based slide preparation method], except cervical or vaginal) to the case. But CPT® coding principles and Correct Coding Initiative (CCI) edits ensure that you should not do so. Code 88173 includes all standard-stain slides, regardless of the preparation type. 

Say yes to cell block: The only exception to the above statement is the cell block. If the pathologist examines clot or cell-block sections from the remaining aspirate, that warrants a unit of 88305. 

Watch IHC units: For the immunohistochemistry (IHC) stains, you should report 88342 for the first stain on a single specimen — and this case has two specimens: the 88173 FNA slides and the 88305 cell block. You should also report +88341 for each additional IHC stain per specimen. With two IHC stains (thyroid peroxidase and CD56) on each of two specimens, that gives you 88342 and +88341 for the FNA slides, and 88342 and +88341 for the cell block.