Pathology/Lab Coding Alert

You know how to use 88361 for tests such as Her-2/neu protein overexpression, but do you remember how to code for related tests -- fluorescence in-situ hybrid-ization (FISH) for gene amplification? Physicians may order either or both types of tests to evaluate certain conditions such as breast cancer.

How Should You Report These Scenarios?
 
Scenario 1: A physician orders a urine test to assess possible bladder-cancer recurrence. The lab performs a test consisting of four DNA probes, counting the fluorescent signal from interphase nuclei of 200 cells. The pathologist interprets the test, finding no evidence of recurrent bladder cancer.

Solution 1: Because this is a nontissue sample (urine), you should use the molecular cytogenetics codes 88271-88275. You report these codes as building blocks, using the appropriate code for each step of the complete cytogenetics study. List the four DNA probes as 88271 x 4 (Molecular cytogenetics; DNA probe, each [e.g., FISH]), and the quantification as CPT 88275 (Molecular cytogenetics; interphase in situ hybridization, analyze 100-300 cells). Report the pathologist's interpretation as 88291 (Cytogenetics and molecular cytogenetics, interpretation and report).

Scenario 2: A surgeon submits a breast lumpectomy specimen and requests an immunohistochemistry test for HER-2/neu protein overexpression to evaluate the patient's suitability for Herceptin therapy. The pathologist examines the breast tumor tissue, including margin evaluation and examination and quantification of IHC stained slides.

Solution 2: For the lumpectomy microscopic examination, you should use 88307 (Level V - Surgical pathology, breast, excision of lesion, requiring microscopic evaluation of surgical margins). Report the IHC-based morphometric test for HER-2/neu protein overexpression as 88361 (Morphometric analysis; tumor immunohistochemistry [e.g., Her-2/neu, estrogen receptor/progesterone receptor], quantitative or semiquantitative).

Scenario 3: The lab performs a FISH test on breast tissue to detect amplification of the HER-2/neu gene. The test consists of two DNA probes and involves quantifying signals from the probes in 80 interphase nuclei from tumor cells and calculating a hybridization ratio. An independent pathologist interprets the test as negative for amplification of the HER-2/neu gene.

Solution 3: Report 88365 (Tissue in situ hybridization, interpretation and report) with modifier -TC (Technical component) for the lab's technical work for the in situ hybridization using two DNA probes, and the independent pathologist's interpretation as 88365 with modifier -26 (Professional component). For the adjunct quantification of gene amplification, report 88358 (Morphometric analysis; tumor [e.g., DNA ploidy]) with -TC for the technical component, and modifier -26 for the pathologist's professional work.

Dennis Padget, MBA, CPA, FHFMA, president of DLPadget Enterprises Inc. in Simpsonville, Ky., helped prepare these scenarios and solutions.

Remember that according to the College of American Pathologists, CMS, and the AMA, you should use different codes for tissue than for nontissue FISH. "Documentation from these three sources states that you should report 88365 (Tissue in situ hybridization, interpretation and report) when testing tissue sources, and codes from molecular cytogenetics (88271-88275 and 88291) when testing nontissue sources," Padget says

You can review FISH coding rules in the October 2003 issue of Pathology/Lab Coding Alert in the article  "Think You're Coding FISH Procedures Correctly? Not if You Aren't Following These Rules."