Summary & Overview
CPT 81194: NTRK Translocation Analysis on FFPE Tumor Tissue
CPT code 81194 designates the technical laboratory procedure to analyze NTRK translocations in tumor tissue, detecting alterations in the NTRK1, NTRK2, and NTRK3 genes that may drive TRK-mediated tumor growth. This molecular diagnostic service is important nationally because NTRK fusions, while rare, have actionable implications for targeted therapies across multiple solid tumor types, influencing treatment selection and precision oncology pathways.
Key payers addressed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The publication outlines payer coverage patterns, coding and billing considerations for the technical component, and clinical context for when NTRK testing is performed.
Readers will find benchmarks on utilization and payer coverage summaries, a concise review of the clinical indications and specimen types (FFPE tumor tissue), and a reference of common billing modifiers and implementation considerations. The content is intended to inform coding staff, laboratory administrators, and policy analysts about the role of 81194 in molecular testing workflows and payer interactions at a national level.
Billing Code Overview
CPT code 81194 covers the technical laboratory analysis performed on a specimen, such as formalin–fixed paraffin embedded tissue (FFPE), to detect NTRK (neurotrophic receptor tyrosine kinase) translocations involving the NTRK1, NTRK2, and NTRK3 genes. These translocations can be associated with TRK-mediated cell proliferation in certain solid tumors.
Service Type: Molecular pathology / molecular diagnostic test (technical component)
Typical Site of Service: Clinical laboratory or pathology laboratory using FFPE tumor tissue specimens
Clinical & Coding Specifications
Clinical Context
A 62-year-old patient with a previously resected soft tissue sarcoma undergoes routine pathology review after recurrence is suspected on imaging. The pathologist requests molecular testing on formalin–fixed paraffin embedded tissue to evaluate for NTRK1, NTRK2, and NTRK3 gene fusions to determine eligibility for TRK inhibitor therapy. The clinical workflow begins with the surgical pathology team selecting an appropriate FFPE block and sending the specimen to a molecular diagnostics laboratory. The laboratory accessioning team logs the specimen, verifies patient identifiers and clinical indication, and assigns the test. A molecular technologist performs the technical assay, which may be an RNA- or DNA-based next-generation sequencing or a validated targeted fusion assay, runs quality controls, and generates raw data. A molecular pathologist reviews analytical results, interprets presence or absence of NTRK translocations, issues a signed report, and communicates findings to the ordering oncologist. Typical sites of service include hospital-based molecular pathology laboratories, independent CAP/CLIA-certified reference laboratories, and academic medical center labs. The service type is a laboratory-based molecular pathology test (technical component).
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional (interpretive) component by the pathologist when technical component is billed separately. |