Summary & Overview
CPT 81311: NRAS Exon 2 and 3 Variant Analysis
CPT code 81311 represents a targeted molecular diagnostic assay that detects hotspot variants in exon 2 (codons 12 and 13) and exon 3 (codon 61) of the NRAS gene. These NRAS mutations have clinical relevance across oncology for tumor characterization and potential targeted therapy decisions, making this test an important component of precision oncology workflows nationally. The code covers the laboratory technical analysis of these specific NRAS regions performed by molecular diagnostic laboratories.
Key payers included in the analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the code’s clinical role, expected service settings, and payer coverage landscape. The publication highlights coding context, common modifiers and billing considerations, and places 81311 within the broader molecular oncology service line.
The report is structured to provide actionable benchmarking and policy context for revenue-cycle and clinical leadership: clarifying what the code represents, where the service is typically performed, and which major national payers are relevant for coverage discussions. Data not available in the input will be noted as such in specific sections.
Billing Code Overview
CPT code 81311 describes a laboratory molecular test that analyzes variants in exon 2 (including codons 12 and 13) and exon 3 (including codon 61) of the NRAS (neuroblastoma RAS viral, v-ras, oncogene homolog) gene. This test identifies specific NRAS hotspot mutations relevant to tumor biology and targeted therapy selection.
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Service type: Molecular diagnostic sequencing and/or targeted variant analysis performed by a clinical molecular laboratory technician or analyst
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Typical site of service: Hospital-based clinical laboratory, independent reference laboratory, or specialized molecular diagnostics laboratory
Clinical & Coding Specifications
Clinical Context
A patient with suspected or confirmed malignancy (for example, metastatic melanoma, colorectal cancer, or acute myeloid leukemia) undergoes targeted tumor genotyping to identify somatic activating mutations in the NRAS gene. A typical scenario: a medical oncologist orders NRAS exon 2 and exon 3 sequencing for a 58-year-old patient with progressive cutaneous melanoma after progression on first-line therapy. A specimen (formalin-fixed paraffin-embedded tumor block or unstained slides) is sent from the pathology department to the molecular diagnostics laboratory. The lab accessioning team verifies patient identifiers and clinical indication, assigns a molecular test order linked to CPT 81311, and performs nucleic acid extraction, PCR amplification or targeted next-generation sequencing focusing on exon 2 (codons 12 and 13) and exon 3 (codon 61), analytic variant calling, and technical review. The laboratory director or molecular pathologist issues a reported result indicating presence or absence of NRAS hotspot variants, with interpretation for therapeutic and prognostic relevance. Typical site of service is an independent or hospital-based molecular diagnostics laboratory or the pathology/molecular lab within an acute care hospital or cancer center.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional interpretation/reporting by a pathologist or laboratory director separate from the technical testing. |