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A quantitative immunoassay for tumor antigen CA 15-3 or CA 27.29 is performed to assess the presence of specific tumor markers in the serum. Tumor antigens, commonly referred to as tumor markers, are substances that can indicate the presence of a malignant neoplasm, which is a type of cancer. The detection of significant circulating levels of these antigens in the blood is often associated with malignancy, particularly in the context of breast cancer. The CA 15-3 and CA 27.29 markers are specifically utilized to monitor the response to treatment in patients diagnosed with stage II and III breast cancer. The CA 15-3 test employs an electrochemiluminescent immunoassay test kit, while the CA 27.29 test utilizes a chemiluminescent immunoassay test kit. Regular testing of these tumor antigens is conducted alongside other clinical methods to effectively monitor the progression or regression of breast cancer, providing valuable information for treatment planning and patient management.
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The quantitative immunoassay for tumor antigen CA 15-3 or CA 27.29 is indicated for the following conditions:
The procedure for conducting the quantitative immunoassay for tumor antigen CA 15-3 or CA 27.29 involves several key steps:
Post-procedure care involves monitoring the patient for any immediate reactions to the blood draw, although such reactions are typically minimal. The results of the immunoassay will be communicated to the healthcare provider, who will interpret the findings in conjunction with other clinical assessments. Regular follow-up testing may be recommended to track changes in tumor marker levels over time, aiding in the ongoing management of breast cancer treatment and evaluation of disease progression or regression.
| Short Descr | IMMUNOASSAY TUMOR CA 15-3 | Medium Descr | IMMUNOASSAY TUMOR ANTIGEN QUANTITATIVE CA 15-3 | Long Descr | Immunoassay for tumor antigen, quantitative; CA 15-3 (27.29) | 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 | 2 | 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. | 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. | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | 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. | GZ | Item or service expected to be denied as not reasonable and necessary | GA | Waiver of liability statement issued as required by payer policy, individual case | Q4 | Service for ordering/referring physician qualifies as a service exemption | 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 | 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 | 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 | GW | Service not related to the hospice patient's terminal condition | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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. | 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. | 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. | 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 | PN | Non-excepted service provided at an off-campus, outpatient, provider-based department of a hospital | Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | TR | School-based individualized education program (iep) services provided outside the public school district responsible for the student | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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| 2011-01-01 | Changed | Short description changed. |
| 2001-01-01 | Added | First appearance in code book in 2001. |
| 1992-12-31 | Deleted | Code deleted. |
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