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The CPT® Code 80204 refers to a laboratory test specifically designed to monitor therapeutic levels of methotrexate, which is a medication utilized in chemotherapy and immunosuppressive therapy. Methotrexate is commonly prescribed for various conditions, including different types of cancer such as breast, bone, blood, lung, head, and neck cancers. Additionally, it is employed in the treatment of autoimmune disorders like rheumatoid arthritis (RA) and psoriasis. The drug functions by inhibiting the growth of cancer cells, suppressing the immune response, and slowing the production of new skin cells, which is particularly beneficial in managing inflammatory arthritis. Regular monitoring through this laboratory test is crucial, especially after administering high doses of methotrexate, as it helps in detecting and tracking blood concentration levels to identify potential toxic effects that may impact vital organs such as the liver, kidneys, lungs, or bone marrow. The testing process involves drawing a venous blood sample, which is then analyzed using an enzyme immunoassay technique. The results obtained from this test are compared against established reference values indicative of healthy individuals, with particular attention given to serum concentrations that may indicate clinical toxicity, specifically when levels exceed 10 umol/L at 24 hours, 1 umol/L at 48 hours, and 0.1 umol/L at 72 hours post-administration.
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The laboratory test associated with CPT® Code 80204 is indicated for monitoring therapeutic levels of methotrexate in patients undergoing treatment for various conditions. The specific indications include:
The procedure for conducting the laboratory test under CPT® Code 80204 involves several key steps, which are outlined as follows:
After the laboratory test is completed, the results are typically reviewed by the healthcare provider to assess the patient's methotrexate levels. If the serum concentrations are found to be elevated, further evaluation may be necessary to determine the appropriate course of action, which could include adjusting the methotrexate dosage or implementing additional monitoring strategies. Patients may be advised on the importance of follow-up testing at specific intervals to ensure ongoing safety and efficacy of their treatment regimen. It is also essential to monitor for any signs of toxicity, such as liver, kidney, lung, or bone marrow disorders, which may necessitate immediate medical attention.
| Short Descr | DRUG ASSAY METHOTREXATE | Medium Descr | DRUG ASSAY METHOTREXATE | Long Descr | Methotrexate | Status Code | Statutory Exclusion (from MPFS, may be paid under other methodologies) | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 9 - Not Applicable | Multiple Procedures (51) | 9 - Concept does not apply. | Bilateral Surgery (50) | 9 - Concept does not apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 9 - Concept does not apply. | Co-Surgeons (62) | 9 - Concept does not apply. | Team Surgery (66) | 9 - Concept does not apply. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | CLIA Waived (QW) | No | APC Status Indicator | Conditionally packaged laboratory tests | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | none | MUE | 1 |
| 90 | Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number. | 26 | Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number. | 91 | Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient. |
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| 2021-01-01 | Added | Code added. |
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