Pathology/Lab Coding Alert

3 scenarios put your cancer immunophenotyping coding knowledge to the test

Still trying to figure out the ICD9 Codes 2005 surgical pathology codes for flow cytometry panels? This quiz will help you determine whether you're on the right track with the new codes.

Scenario 1: A flow cytometry panel includes three tubes: CD10/CD19, kappa/CD19 and lambda/CD19. Does this panel represent three, four or six markers?

Solution 1: This panel involves four markers for coding purposes: CD10, CD19, lambda, and kappa. Although the test involves three tubes and six markers if you count repeats, the proper count is four unique markers. You should report the technical service as 88184 (Flow cytometry, cell surface, cytoplasmic, or nuclear marker, technical component only; first marker) plus three units of +88185 (... each additional marker [list separately in addition to code for first marker]).

For the pathologist's interpretation of the entire panel, you should bill 88187 (Flow cytometry, interpretation; 2 to 8 markers).

Scenario 2: The pathologist examines a lymph node biopsy and finds lymphocyte proliferation. Suspecting lymphoma, the pathologist runs a flow cytometry panel consisting of CD3 (total T cells), CD4, CD5, CD8, CD10, CD14, CD16/56 (NK cells), CD19 (B cells), CD20, CD23, CD45, kappa, and lambda. How should you code this?

Solution 2: First, report 88305 (Level IV - Surgical pathology, gross and microscopic examination, lymph node, biopsy) for the pathologist's evaluation of the lymph node biopsy.

For flow cytometry, the panel consists of 13 different antibody markers. You should report 88184 plus 12 units of 88185 for the technical component of the panel. For the pathologist's interpretation, report 88188 (Flow cytometry, interpretation; 9 to 15 markers).

Although CPT 2005 provides separate codes in the immunology section for T cells (86359, T cells; total count), B cells (86064, B cells, total count), and NK cells (86379, Natural killer [NK] cells, total count), you should not use these codes for this procedure. Because the pathologist evaluates this marker panel as part of an evaluation for suspected lymphoma, which includes a professional interpretation of the entire panel, you should report the entire service using the flow cytometry codes.

A note added to the immunology section of CPT 2005 states, "For flow cytometric immunophenotyping for the assessment of potential hematolymphoid neoplasia, see 88182, 88184-88189."

The codes in the immunology section represent total-count clinical lab tests and do not involve a pathologist's professional interpretation service. Physicians use the immunology codes for lab tests that assess immunologic status of patients for
situations such as transplant services or HIV monitoring.

Scenario 3: The lab runs a three-color flow cytometry panel that uses the third-color antibody (CD45) in every tube for gating purposes. The tubes are:

 CD19/kappa/CD45

 CD19/lambda/CD45

 CD 20/CD5/CD45

 FMC7/CD23/CD45

 CD19/CD10/CD45.

For this panel, the lab uses two additional tubes for calibration purposes, and does not report a result from these tubes:

 IgG1/IgG2/CD45

 IgG1/IgG2/IgG1.

What is the proper coding for this panel?

Solution 3: The unit of service for the technical component is the antibody. That means you should report the third-color antibody (CD45) only once, even though the lab uses it in every tube.

Regarding the calibration tubes, Medicare never allows labs to report tests that they run for standardization or quality control. You should not bill for the tubes that you use to calibrate your equipment.

Do this: Count each unique marker; don't count a marker more than once if it appears in other combinations. The total antibody count for this panel is nine markers (CD19, kappa, lambda, CD20, CD5, FMC7, CD23, CD10, and CD45). Correct coding for the scenario is 88184 and eight units of 88185 for the technical work. You should also report 88188 for the pathologist's interpretation of the panel.

Editor's note: Flow cytometry examples were prepared with the assistance of LuAnn Lubell, MT (ASCP), systems analyst; and Emily Shipman and Joanne Granger with Ohio Health in Columbus; Peggy Slagle, CPC, billing compliance coordinator at the University of Nebraska Medical Center in Omaha; and Walt Williams, billing and reimbursement specialist with Genoptix in San Diego.