Summary & Overview
HCPCS G0251: LINAC Stereotactic Radiosurgery, Fractionated Per Session
HCPCS Level II code G0251 represents linear accelerator (LINAC) based stereotactic radiosurgery delivered with collimator changes and custom plugging for fractionated treatments, billed per session with up to five sessions per course. This code defines a high-precision external beam radiation therapy service used to treat one or more lesions with stereotactic technique, distinguishing it from single-fraction radiosurgery or standard fractionated radiotherapy.
The analysis covers coverage and payment considerations for major national payers: Aetna, Blue Cross Blue Shield plans, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of clinical context for LINAC-based stereotactic radiosurgery, common billing and service-line implications, and benchmarking expectations across the listed payers where available.
This publication summarizes coding intent, typical site-of-service settings (radiation oncology clinics and hospital outpatient departments), and what payers typically review for medical necessity when authorizing fractionated stereotactic radiosurgery. It also outlines where data is available and notes items not provided in the input. Topics include payer coverage scope, session limits embedded in the code definition, and implications for radiation oncology service lines and revenue cycle workflows.
Billing Code Overview
HCPCS Level II code G0251 describes linear accelerator based stereotactic radiosurgery delivered with associated collimator changes and custom plugging, for fractionated treatment of lesions. The code is reported per session, with a maximum of five sessions per course of treatment.
Service type: Stereotactic radiosurgery (fractionated) using linear accelerator (LINAC)
Typical site of service: Radiation oncology departments and hospital outpatient radiation therapy centers providing LINAC-based stereotactic radiosurgery.
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult with one or more intracranial metastases or a small primary brain tumor referred to radiation oncology for fractionated stereotactic radiosurgery delivered using a linear accelerator. The patient presents after multidisciplinary evaluation (neuro-oncology, neurosurgery, and radiation oncology) with high-resolution MRI and planning CT scans. Immobilization using a frameless stereotactic mask system is applied, and a treatment plan is created with image-guided localization and multiple non-coplanar beams or arcs. Treatment sessions include collimator changes and custom plugging as needed to shape the dose to multiple lesions. The usual course is up to five sessions (G0251) delivered on consecutive or alternate days. Typical workflow steps: consultation and consent; simulation with CT and MRI fusion; immobilization device fabrication; treatment planning with target and OAR contouring; physics QA and plan approval; daily image guidance and delivery including any required collimator changes and custom blocking/plugging; on-treatment assessments and follow-up imaging.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional (physician) portion of service if separated from technical component. |