Summary & Overview
CPT 77402: External Beam Radiation Therapy, Level 1
CPT code 77402 identifies level 1 complexity external beam radiation therapy, a basic technical-component service used for treatments that rely on single- or multiple-electron fields or two-dimensional photon techniques. As a simpler external beam modality, it remains relevant for cases where advanced volumetric imaging or highly conformal planning is not required but where imaging guidance for setup may still be used. Nationally, this code matters because it distinguishes lower-complexity radiation delivery from intermediate and high-complexity services, affecting billing, workflow, and service-line categorization across radiation oncology providers.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the clinical context and the technical nature of the service, plus benchmarking and reimbursement context where available. The publication outlines typical sites of service, common billing modifiers and practical coding considerations tied to the technical component, and how 77402 compares to higher-complexity external beam radiation codes. The content is intended to help administrators, coders, and policy analysts understand the role of this lower-complexity radiation therapy code in program management, payer interactions, and coding strategy.
Data not available in the input: Associated taxonomies, ICD-10 diagnoses, related codes, and detailed payer-specific reimbursement rates.
Billing Code Overview
CPT code 77402 denotes external beam radiation therapy, level 1 complexity, representing a simpler form of radiation treatment. The service may involve single-electron fields, multiple-electron fields, or two‑dimensional (2D) photon therapy, where beams are shaped and aimed using surface or bony landmarks rather than advanced volumetric imaging. The description notes that imaging guidance, when performed, is included to assist with setup and target localization.
Service type: External beam radiation therapy (lower complexity technical component)
Typical site of service: Radiation oncology treatment centers, hospital outpatient departments, or freestanding radiation therapy centers
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult with a localized, low‑complexity tumor such as a superficial skin malignancy, small localized breast lesion after lumpectomy, or a palliative bone metastasis where a simple external beam technique is appropriate. The patient presents to a freestanding radiation oncology clinic or hospital outpatient radiation therapy department for fractionated external beam radiation therapy delivered using single‑electron fields, multiple electron fields, or two‑dimensional photon planning based on surface or bony landmarks rather than volumetric CT‑based planning. The initial workflow includes physician evaluation, simulation using simple immobilization and planar imaging or fluoroscopy as needed, delineation of target and critical structures using 2D landmarks, generation of a basic treatment plan, and daily setup with portal or planar imaging for positioning. Treatment sessions are delivered by a radiation therapist under the supervision of the radiation oncologist; dosimetry and physics perform QA appropriate for level 1 complexity. Common scenarios include post‑operative small breast field irradiation, palliation of localized bone pain, or treatment of superficial skin cancers where advanced 3D or IMRT techniques are not required.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | When billing only the physician’s interpretation/supervision component separate from technical delivery |