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A quantitative immunoassay for tumor antigen CA 125 is a laboratory test that measures the level of the CA 125 protein in the blood. CA 125 is a type of tumor marker, which is a substance produced by cancer cells or by normal cells in response to cancer in the body. The presence of elevated levels of CA 125 in the serum can indicate the presence of a malignant neoplasm, particularly in the context of ovarian cancer. This test is particularly significant for patients who have a documented ovarian mass, as it aids in differentiating between benign and malignant conditions. Additionally, the CA 125 test is utilized to monitor the effectiveness of treatment in patients who have already been diagnosed with ovarian, fallopian tube, or endometrial cancer. The test employs an electrochemiluminescent immunoassay test kit, which is a sophisticated method that enhances the sensitivity and specificity of the measurement. Regular monitoring of tumor antigen levels is essential, as it provides valuable information regarding the progression or regression of the malignancy when used alongside other clinical assessments.
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The quantitative immunoassay for tumor antigen CA 125 is indicated for the following conditions:
The procedure for conducting the quantitative immunoassay for tumor antigen CA 125 involves several key steps:
After the quantitative immunoassay for tumor antigen CA 125 is completed, the patient may resume normal activities immediately, as there are typically no significant post-procedure restrictions. The results of the test are usually available within a few hours to a few days, depending on the laboratory's processing time. It is important for healthcare providers to discuss the results with the patient, as elevated CA 125 levels may necessitate further diagnostic evaluations or adjustments in treatment plans. Regular monitoring may be recommended to track changes in CA 125 levels over time, providing insights into the effectiveness of ongoing treatment or the need for additional interventions.
| Short Descr | IMMUNOASSAY TUMOR CA 125 | Medium Descr | IMMUNOASSAY TUMOR ANTIGEN QUANTITATIVE CA 125 | Long Descr | Immunoassay for tumor antigen, quantitative; CA 125 | 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) | T1H - Lab tests - other (non-Medicare fee schedule) | MUE | 1 | CCS Clinical Classification | 235 - Other Laboratory |
| GA | Waiver of liability statement issued as required by payer policy, individual case | 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. | GZ | Item or service expected to be denied as not reasonable and necessary | Q4 | Service for ordering/referring physician qualifies as a service exemption | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | GY | Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | X2 | Continuous/focused services: for reporting services by clinicians whose expertise is needed for the ongoing management of a chronic disease or a condition that needs to be managed and followed with no planned endpoint to the relationship; reporting clinician service examples include but are not limited to: a rheumatologist taking care of the patient's rheumatoid arthritis longitudinally but not providing general primary care services | GX | Notice of liability issued, voluntary under payer policy | 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. | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | 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. | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | GW | Service not related to the hospice patient's terminal condition | KX | Requirements specified in the medical policy have been met | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area |
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| 2024-01-01 | Changed | Guideline information changed. |
| 2011-01-01 | Changed | Short description changed. |
| 2001-01-01 | Added | First appearance in code book in 2001. |
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