Summary & Overview
CPT 0019U: RNA Expression–Based Tumor Profiling and Therapeutic Matching
CPT code 0019U designates a Proprietary Laboratory Analyses (PLA) test—OncoTarget and OncoTreat—that measures RNA gene expression in tumors and uses an algorithm to match molecular activity patterns with potential therapeutic agents. As a PLA code, 0019U refers to a single manufacturer-specific/laboratory-specific assay, which matters nationally as precision oncology assays increasingly inform targeted treatment decisions and coverage determinations. The code signals a complex molecular diagnostic service that may intersect with medical oncology, pathology, and precision medicine programs.
Key payers considered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of the clinical purpose of the test, the service setting, common billing modifiers, and what to expect from payer engagement at a national level. The publication summarizes benchmarks and coverage themes relevant to proprietary molecular assays, highlights policy updates affecting PLA codes broadly, and provides clinical context about how RNA expression–based matching tools are used in treatment planning. The content aims to help billing staff, laboratory administrators, and policy analysts understand the coding designation, typical site-of-service, and the national payer landscape for CPT code 0019U.
Data not available in the input for specific associated taxonomies, ICD-10 diagnoses, related codes, and service line details.
Billing Code Overview
CPT code 0019U is a Proprietary Laboratory Analyses (PLA) code that describes a single, specific laboratory test: OncoTarget and OncoTreat developed by DarwinHealth in collaboration with the Columbia University Department of Pathology and Cell Biology. The test evaluates RNA gene expression in tumor tissue and applies a computational algorithm to match tumor activity signatures with potential therapeutic agents.
Service Type: Laboratory molecular diagnostic test with algorithmic therapeutic matching
Typical Site of Service: Clinical laboratory or hospital outpatient laboratory
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A 62-year-old patient with metastatic, treatment-refractory colorectal adenocarcinoma presents to a tertiary cancer center for precision oncology testing to guide systemic therapy selection. Prior lines of standard chemotherapy and targeted agents produced limited response; the oncology team requests a molecular functional assay to evaluate tumor biology and predict drug sensitivity. A formal pathology review identifies an adequate formalin-fixed paraffin-embedded (FFPE) tumor block or recent core biopsy specimen. The specimen is sent to the proprietary laboratory performing the OncoTarget and OncoTreat assay described by 0019U.
The laboratory extracts RNA from the tumor sample, performs gene expression profiling, and applies the vendor algorithm to map tumor transcriptional activity to drugs and drug classes with predicted efficacy. Results are returned as a report listing prioritized therapeutic agents and pathways with supporting evidence. The treating oncologist reviews the report in a multidisciplinary tumor board, documents clinical interpretation, and integrates recommendations into the next-line treatment plan. Billing for the assay is submitted using PLA code 0019U with appropriate diagnosis codes reflecting the patient’s malignancy and clinical status. Typical site of service is an outpatient cancer center, pathology lab, or reference laboratory performing specialized molecular testing.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when only the physician interpretation/reporting portion of the test is billed separately from the technical lab processing. |
TC | Technical component | Use when only the laboratory technical processing (specimen analysis) is billed by the performing lab. |
52 | Reduced services | Use when the assay is partially performed with reduced scope or shortened protocol resulting in reduced work or resources. |
53 | Discontinued procedure | Use when specimen processing/testing is started but discontinued due to inability to obtain adequate tissue or assay failure. |
59 | Distinct procedural service (Note: not in provided list) | Data not available in the input. |
62 | Two surgeons (Note: not typical for lab tests) | Use when two independent providers perform separate components of testing or interpretation — rarely applicable. |
80 | Assistant surgeon (Note: not applicable) | Data not available in the input. |
AD | Attending doctor main surgeon (Note: CMS-specific for inpatient) | Use only per payer policy when reporting attending responsibility for a component of testing or interpretation. |
QK | Medical direction of two, three, or four technicians | Use if the ordering physician medically directs multiple technical staff performing parts of the assay per payer rules. |
QX | CRNA service: performed with medical direction by a physician | Not applicable for this procedure; included when billing systems require one of the Q modifiers from supplied list. |
QY | Medical direction of one certified registered nurse anesthetist (Note: not applicable) | Not used for lab assays but listed among available modifiers. |
22 | Increased procedural services | Use when work or complexity for the interpretation/report is substantially greater than typical and payer allows 22 for lab interpretation. |
59 | Data not available in the input | Data not available in the input. |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
| 208000000X | Medical Oncology | Treating oncologists order the assay and integrate results into systemic therapy selection. |
| 207Q00000X | Anatomic Pathology | Pathologists confirm specimen adequacy and may provide the pathology report accompanying the molecular assay. |
| 207P00000X | Hematology-Oncology | Specialists in malignant diseases who commonly order advanced tumor profiling assays. |
| 2086S0202X | Molecular Genetic Pathology | Laboratory directors and molecular pathologists oversee assay validation and interpretation. |
| 363LA2200X | Laboratory Director | Clinical laboratory directors or pathologists responsible for laboratory testing oversight. |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
| Data not available in the input. | Data not available in the input. | Data not available in the input. |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
88305 | Level IV surgical pathology, gross and microscopic examination | Pathology review and preparation of the FFPE block or confirmatory diagnostic pathology often precedes molecular profiling like 0019U. |
88342 | Immunohistochemistry, per single antibody stain | IHC may be performed to characterize tumor biomarkers or to select appropriate tissue prior to RNA-based assays. |
88172 | Cytopathology, rapid interpretation, intraoperative or percutaneous procedures (if applicable) | Rapid adequacy assessment of core biopsy specimens guiding whether sufficient tissue is available for the 0019U assay. |
81479 | Unlisted molecular pathology procedure | Occasionally used for custom or supplementary molecular tests when not covered by a PLA code; related when additional non‑PLA testing is ordered. |
94640 | Pulmonary function test (Note: not applicable) | Data not available in the input. |