Summary & Overview
CPT 81203: APC Gene Insertion/Deletion Analysis
CPT code 81203 denotes a molecular diagnostic laboratory test that analyzes specific insertions and deletions in the adenomatous polyposis coli (APC) gene. This targeted analysis is clinically important because pathogenic APC variants are associated with familial adenomatous polyposis and elevated colorectal cancer risk, making accurate detection essential for diagnosis, surveillance planning, and family cascade testing. Nationally, molecular testing codes like 81203 are central to precision medicine and genetic risk stratification.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of clinical context for APC insertion/deletion testing, typical sites of service and service type, and the payer landscape relevant to coverage and billing. The publication summarizes benchmarks where available, highlights common billing considerations, and explains how CPT code 81203 fits into molecular diagnostic workflows. Data not available in the input is noted where applicable.
Billing Code Overview
CPT code 81203 describes a laboratory technical procedure that analyzes specific changes involving repeated or deleted nucleotides in the adenomatous polyposis coli (APC) gene. This test detects small-scale insertions and deletions that can alter the APC gene sequence and contribute to hereditary colorectal cancer syndromes.
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Service type: Molecular diagnostic testing (targeted sequencing for insertion/deletion variants)
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Typical site of service: Clinical molecular laboratory or hospital-based molecular diagnostics laboratory
Clinical & Coding Specifications
Clinical Context
A 38-year-old patient with a strong family history of colorectal cancer and multiple colorectal adenomas is referred for hereditary colorectal cancer genetic testing. The clinician orders molecular analysis of the adenomatous polyposis coli (APC) gene to evaluate for pathogenic sequence alterations such as small deletions or insertions and repeat unit changes that cause familial adenomatous polyposis (FAP). The typical clinical workflow: the ordering provider (medical geneticist, gastroenterologist, or genetic counselor) obtains informed consent and a peripheral blood specimen; the specimen is sent to a molecular diagnostics laboratory. The laboratory performs the technical assay, including DNA extraction, targeted APC gene analysis using appropriate methods (e.g., PCR-based sizing, fragment analysis, or next-generation sequencing with analysis targeted to repetitive or deleted regions), and validates detected variants. The laboratory reports technical findings and forwards interpretive results to the ordering provider for clinical correlation and management. Typical site of service is an outpatient molecular diagnostics laboratory or hospital-based clinical laboratory that performs hereditary cancer testing.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional interpretation component by the laboratory director or pathologist, if separated from technical component. |