Summary & Overview
CPT 81193: NTRK3 Translocation Testing on FFPE Tumor Tissue
CPT code 81193 represents a technical molecular pathology assay to detect NTRK3 translocations in formalin–fixed paraffin embedded (FFPE) tumor tissue. Testing for NTRK3 fusions matters nationally because these alterations can drive TRK-mediated oncogenesis and inform diagnostic classification and targeted therapy decisions for certain solid tumors, including congenital/infantile fibrosarcoma. The code captures the laboratory technical component of a targeted fusion analysis performed on clinical tumor specimens.
Key payers in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the clinical context for NTRK3 fusion testing, the laboratory service setting, and the primary payers affecting coverage and claims processing. The publication also summarizes common billing modifiers and highlights areas where policy or coding clarity may affect reimbursement and billing practices.
The report is intended for clinicians, laboratory managers, and billing professionals seeking a national overview of CPT code 81193 — what it covers, where it is performed, who pays, and what to consider when preparing claims for molecular oncology fusion testing. Data not available in the input are noted where applicable.
Billing Code Overview
CPT code 81193 describes a laboratory technical test performed on a specimen such as formalin–fixed paraffin embedded tissue (FFPE) to analyze NTRK3 (neurotrophic receptor tyrosine kinase 3) translocations, which can be associated with TRK-mediated cell proliferation in certain solid tumors, including congenital/infantile fibrosarcoma. The procedure focuses on detecting gene rearrangements that have diagnostic, prognostic, or therapeutic relevance in oncology.
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Service type: Molecular pathology / targeted genetic fusion testing
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Typical site of service: Clinical molecular pathology laboratory or hospital pathology lab performing testing on FFPE tumor specimens
Clinical & Coding Specifications
Clinical Context
A pediatric patient aged 2 months presents with a rapidly growing soft-tissue mass on the extremity. Imaging suggests a congenital/infantile soft-tissue tumor. A core needle biopsy is performed and submitted as formalin-fixed paraffin-embedded tissue (FFPE) to the pathology laboratory. The lab performs histology and immunohistochemistry; based on morphology and clinical suspicion for TRK-driven neoplasia, the lab orders molecular testing for NTRK3 gene rearrangements. The laboratory technologist extracts nucleic acid from the FFPE specimen and runs a validated molecular assay (RNA-based next-generation sequencing or a validated targeted fusion assay) to detect NTRK3 translocations. Results are interpreted by a molecular pathologist and reported in the pathology report, documenting presence or absence of NTRK3 fusions to guide potential targeted therapy decisions and clinical management. Typical site of service is an outpatient or hospital-based pathology/molecular diagnostics laboratory that receives FFPE tissue from ambulatory surgical centers, hospital operating rooms, or interventional radiology suites.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional (interpretive) component of a split technical/professional molecular test performed by a pathologist or laboratory director. |