Summary & Overview
CPT 86294: Tumor Antigen Immunoassay
CPT code 86294 covers qualitative or semiquantitative immunoassays performed to detect tumor antigens in patient specimens. These laboratory tests support cancer diagnosis, monitoring, or recurrence surveillance by identifying tumor-associated proteins or markers. Nationally, tumor antigen immunoassays are a routine component of oncology laboratory services and influence clinical decision-making, care pathways, and laboratory billing practices.
Key payers included in this analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. This publication outlines clinical context for the assay, typical sites of service, and the operational and coding considerations that affect billing and coverage nationally.
Readers will find benchmarks for service classification, summary guidance on common modifiers and billing mechanics, and a concise clinical context describing the assay’s role in oncology testing. Where input data is missing, the report indicates "Data not available in the input." The content is intended to inform coding, billing review, and administrative planning for laboratories and payers at a national level.
Billing Code Overview
CPT code 86294 describes a laboratory qualitative or semiquantitative immunoassay performed by a lab analyst to evaluate a patient specimen for a tumor antigen. The service type is laboratory testing / immunoassay for tumor marker detection. The typical site of service is a clinical laboratory or hospital laboratory, where trained laboratory personnel process and analyze patient specimens for tumor-associated antigens.
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A 62-year-old patient with a history of colorectal cancer in surveillance presents for routine laboratory monitoring. The oncologist orders a serum tumor marker immunoassay to assess for recurrence or progression. A phlebotomist collects a blood specimen at the ambulatory oncology clinic and sends it to the hospital clinical laboratory. A laboratory analyst performs a qualitative or semiquantitative immunoassay to detect a tumor-associated antigen in the patient’s serum. The test generates an interpreted result that is routed to the ordering oncologist via the electronic health record. Typical site of service includes hospital clinical laboratories, independent reference laboratories, and outpatient oncology or ambulatory clinics with on-site lab services. The procedure is used for monitoring known malignancy, assessing response to therapy, or as part of diagnostic workup when clinical suspicion for a tumor marker–producing neoplasm exists.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when reporting only the professional interpretation component provided by a laboratory physician or pathologist for the immunoassay result |
TC | Technical component | Use when reporting only the technical component (laboratory processing and testing) without physician interpretation |
90 | Reference (outside) laboratory | Use when the specimen is sent to an outside reference laboratory that performs the test |
52 | Reduced services | Use when the test is performed but with substantially reduced methodology or fewer analytes than typical |
53 | Discontinued procedure | Use if specimen collection or testing was started but discontinued for clinical reasons before completion |
59 | Distinct procedural service | Not listed in input list; omitted to comply with provided modifiers |
91 | Replicate clinical diagnostic test | Not listed in input list; omitted to comply with provided modifiers |
76 | Repeat procedure by same physician/provider | Not listed in input list; omitted to comply with provided modifiers |
90 | Duplicate entry avoided; already listed above | Duplicate entries are not used |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
207RG0300X | Clinical Laboratory Director | Physicians or laboratory directors overseeing immunoassay testing and quality assurance |
261QM0800X | Hematology & Oncology | Oncologists who order tumor marker assays for diagnosis and surveillance |
207K00000X | Pathology | Pathologists who interpret laboratory immunoassay results and provide consultative reporting |
207L00000X | Clinical Cytogenetics/Genetics | Laboratory specialists involved when tumor antigen testing is part of broader molecular workup |
3336C0003X | Clinical Laboratory Technologist | Laboratory technologists and analysts performing the immunoassay testing |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
C18.9 | Malignant neoplasm of colon, unspecified | Tumor antigen assays often used for surveillance and recurrence detection in colorectal cancer |
C20 | Malignant neoplasm of rectum | Rectal cancer patients frequently monitored with tumor markers relevant to this assay |
C50.919 | Malignant neoplasm of unspecified site of unspecified female breast | Breast cancer surveillance and monitoring may include tumor antigen testing depending on marker specificity |
C34.90 | Malignant neoplasm of unspecified part of unspecified bronchus or lung | Certain lung cancers produce tumor-associated antigens measured by immunoassays |
C61 | Malignant neoplasm of prostate | Prostate cancer monitoring commonly uses specific antigen assays; qualitative immunoassays may be adjunctive |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
36415 | Collection of venous blood by venipuncture | Specimen collection commonly performed prior to the immunoassay |
84460 | Assay of tumor marker, carcinoembryonic antigen (CEA), quantitative | Quantitative tumor marker assay that may be ordered alongside qualitative/ semiquantitative immunoassays for comprehensive monitoring |
86304 | Antibody; screen, each (e.g., influenza) — immunoassay | Example immunoassay methodology code family; related in laboratory technique though different analytes |
86357 | Therapeutic drug assay, qualitative or semiquantitative, per test | Represents qualitative/ semiquantitative reporting methodology similar to the tumor antigen immunoassay |
86485 | Antigen detection by immunoassay technique, qualitative or semiquantitative, single step method | Alternative immunoassay technique codes used in the workflow for antigen detection |