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A quantitative immunoassay for tumor antigen CA 19-9 is a laboratory test that measures the levels of the CA 19-9 antigen in the blood or other body fluids. Tumor antigens, commonly known as tumor markers, are substances that can indicate the presence of a malignant neoplasm, or cancer. The presence of significant levels of CA 19-9 in the serum is often associated with malignancies, particularly those affecting the pancreas, colon, stomach, or biliary system. This test is particularly valuable for monitoring the response to treatment in patients who have already been diagnosed with these types of cancers. The CA 19-9 test employs an electrochemiluminescent immunoassay test kit, which is a sophisticated method that enhances the sensitivity and specificity of the measurement. It is important to note that if the test is conducted on body fluids other than blood, the specific source of the fluid must be clearly identified. Regular testing of tumor antigens like CA 19-9 is typically used alongside other clinical assessments to evaluate the progression or regression of cancer, providing critical information for ongoing patient management.
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The CA 19-9 immunoassay is indicated for the following conditions:
The procedure for conducting the CA 19-9 immunoassay involves several key steps:
After the CA 19-9 immunoassay is performed, the patient may not require any specific post-procedure care, as the test is minimally invasive. However, it is important for healthcare providers to discuss the results with the patient, as elevated levels of CA 19-9 may necessitate further diagnostic evaluations or adjustments in treatment plans. Regular monitoring may be recommended based on the patient's clinical status and treatment response. Additionally, healthcare providers should ensure that the patient understands the significance of the test results in the context of their overall cancer management strategy.
| Short Descr | IMMUNOASSAY TUMOR CA 19-9 | Medium Descr | IMMUNOASSAY TUMOR ANTIGEN QUANTITATIVE CA 19-9 | Long Descr | Immunoassay for tumor antigen, quantitative; CA 19-9 | 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 |
| 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | GZ | Item or service expected to be denied as not reasonable and necessary | 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 | 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 | 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 | 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. | GW | Service not related to the hospice patient's terminal condition | 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. | 76 | Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | 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. | 95 | Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | 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 | 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 | TC | Technical component; under certain circumstances, a charge may be made for the technical component alone; under those circumstances the technical component charge is identified by adding modifier 'tc' to the usual procedure number; technical component charges are institutional charges and not billed separately by physicians; however, portable x-ray suppliers only bill for technical component and should utilize modifier tc; the charge data from portable x-ray suppliers will then be used to build customary and prevailing profiles |
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| 2011-01-01 | Changed | Short description changed. |
| 2001-01-01 | Added | First appearance in code book in 2001. |
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