ModifiedUnitedHealthcarePolicy CS105.U

Proton Beam Radiation Therapy

Clinical coverage policy governing use of proton beam radiation therapy (PBT/PBRT) for UnitedHealthcare members aged 19 and older; defines proven indications, requirements for exceptions, and coding references. Does not apply to certain listed states where state-specific policies exist.

Policy Summary

PayerUnitedHealthcare

PolicyProton Beam Radiation Therapy

Policy CodePolicy CS105.U

Change TypeMultiple material additions and revisions (indications addeddocumentation and coding updates)

Effective DateMay 1, 2026

Next Review DateN/A

Key ActionSubmit prior authorization with documentation that photon techniques cannot achieve required normal-tissue sparing and include prior radiation history for reirradiation cases.

SourceLink

POLICY UPDATE CHANGES

Primary Head and Neck Cancers are added as a proven and medically necessary indication for definitive PBT when tumors are near critical structures or have intracranial extension or perineural invasion and photon techniques cannot achieve adequate sparing.

Primary Central Nervous System Tumors are added as a proven and medically necessary indication for definitive PBT when tumors are near critical structures and photon techniques cannot achieve adequate sparing.

Primary mediastinal tumors (e.g., thymomas, mediastinal lymphomas, thoracic sarcomas) are added to the list of proven and medically necessary indications for definitive PBT.

Reirradiation is added as a proven and medically necessary indication when prior radiation was to the same anatomical site and documentation shows photon techniques cannot spare surrounding normal tissue.

The liver indication was broadened from hepatocellular carcinoma alone to primary liver malignancies including hepatocellular carcinoma and intrahepatic cancer (localized, unresectable) with documentation that photon techniques cannot spare normal tissue.

Coverage criteria for exception requests were revised to remove the prior requirement that evaluation include comparison of treatment plans for PBT, IMRT, and SBRT.

Medical records documentation requirements were updated to explicitly include history of prior radiation therapy and the need for additional radiation to the same anatomical site for re-irradiation reviews.

New definitions were added for Base of Skull Tumors, Central Nervous System Tumors, and Head and Neck Cancer; 'Definitive Therapy' definition was updated.

CPT/HCPCS codes 77385, 77386, G6015, G6016, and G6017 were removed from Applicable Codes.

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

19+applies to individuals aged

Younger than 19covered without further review

multiplenew proven indications added

5CPT/HCPCS codes removed

multipleguideline citations

Coverage Criteria for Proton Beam Radiation Therapy

Esophageal cancer — Proton beam therapy (PBT)

Covered when ALL of the following are met:

ALL of the following

The individual has a diagnosis of esophageal or esophagogastric junction cancer.
Proton beam therapy (PBT) is being used with curative intent or as part of definitive multimodality therapy (for example, chemoradiation).
Documentation shows that reduction of dose to critical thoracic organs at risk (for example, heart, lungs) is necessary and cannot be adequately achieved with 3D conformal radiation therapy (3D-CRT) or advanced photon techniques (for example, IMRT) while still meeting target dose requirements.
Treatment planning demonstrates dosimetric advantage of PBT over available photon techniques for the individual (plan comparison or dosimetric justification provided).
Treatment is delivered at a center with appropriate proton therapy expertise and multidisciplinary care for esophageal cancer.

Bladder cancer — Proton beam therapy (PBT)

Considered investigational/selective use — PBT may be considered when ALL of the following are met:

ALL of the following

The individual has muscle-invasive, nonmetastatic bladder cancer and is being treated with bladder-preserving trimodality therapy (maximal transurethral resection of bladder tumor, concurrent chemotherapy, and radiation).
PBT is used as part of multimodality bladder preservation rather than as definitive RT alone (guideline-concordant approach).
Documentation provided that photon-based techniques cannot achieve required normal tissue sparing or that PBT offers clinically meaningful dosimetric advantages for the individual (plan comparison preferred).
The treating team documents that expected oncologic outcomes with PBT are consistent with guideline recommendations for bladder preservation, and long-term follow-up plans are in place.

Breast cancer — Proton beam therapy (PBT)

Coverage stance and required conditions — PBT may be considered when ALL of the following are met:

ALL of the following

The individual has nonmetastatic breast cancer (including postmastectomy or breast/chest wall with regional nodal irradiation) for whom advanced RT is indicated (for example, need for regional nodal irradiation involving internal mammary nodes) and cardiac or pulmonary sparing is clinically important.
Documentation demonstrates that PBT provides a dosimetric advantage expected to meaningfully reduce dose to heart or lungs compared with advanced photon techniques (IMRT/VMAT) and that the dosimetric advantage cannot be achieved with photons without compromising target coverage.
The treating center has experience in breast PBT and devices/techniques to minimize uncertainties (for example, robust planning, respiratory management) and multidisciplinary oversight.
When PBT is used in the adjuvant/postmastectomy setting, the use is consistent with contemporary guideline recommendations or is performed within a clinical trial when guideline uncertainty persists.

Age-related macular degeneration — Proton beam therapy (PBT)

Not routinely covered — PBT is considered unproven and not medically necessary for neovascular age-related macular degeneration (AMD) outside of clinical trials.

ALL of the following

The indication is neovascular (exudative) age-related macular degeneration (AMD).
PBT is only considered when provided in the context of a clinical trial or prospectively consented research protocol; routine clinical use is not supported due to insufficient and inconsistent evidence.

Choroidal hemangioma — Proton beam therapy (PBT)

Selective coverage — PBT may be considered for choroidal hemangioma when ALL of the following are met:

ALL of the following

The individual has a circumscribed choroidal hemangioma requiring radiation therapy (for example, symptomatic tumor with serous retinal detachment, visual compromise) and alternative less invasive treatments (for example, photodynamic therapy) are inadequate, contraindicated, or previously failed.
Documentation includes tumor thickness and characteristics; PBT is preferred when tumor thickness > 3 mm or when single-session proton treatment is judged likely to provide superior anatomic or functional outcomes compared with alternatives.
The treating ophthalmic oncology and radiation teams document that PBT is expected to achieve tumor control while minimizing dose to adjacent ocular structures, and that follow-up for visual function and ocular complications is arranged.

Lung cancer — Proton beam therapy (PBT) supplemental criteria

Supplemental considerations — PBT for lung cancer may be considered in selected circumstances when ALL of the following are met:

ALL of the following

The individual has non-small cell lung cancer (NSCLC) or small cell lung cancer for which definitive or curative-intent radiotherapy is planned and advanced motion-managed simulation and delivery techniques are available (for example, 4D CT, PET/CT, respiratory management).
There is a documented dosimetric or clinical rationale that PBT will better spare critical thoracic organs (for example, heart, lung, esophagus) compared with photon techniques without compromising target coverage; paired IMRT and PBT plans or dosimetric comparison should be provided when feasible.
For early-stage NSCLC, hypofractionated PBT may be an option when SBRT is not suitable due to tumor location or OAR constraints; the planned biologically effective dose and fractionation should be specified and consistent with published experience.
For locally advanced or inoperable disease requiring concurrent chemoradiation, selection of PBT should consider available comparative evidence, center experience, and the potential for higher lung or heart doses with some proton techniques; outcomes and toxicity risks should be discussed and documented.

Applicable Coding and Removed Codes

Applicable CPT CodesCPT

77301	Intensity modulated radiotherapy plan, including dose-volume histograms for target and critical structure partial tolerance specifications.
77338	Multi-leaf collimator (MLC) device(s) for intensity modulated radiation therapy (IMRT), design and construction per IMRT plan.
77387	Guidance for localization of target volume for delivery of radiation treatment, includes intrafraction tracking, when performed.
77520	Proton treatment delivery; simple, without compensation.
77522	Proton treatment delivery; simple, with compensation.
77523	Proton treatment delivery; intermediate.
77525	Proton treatment delivery; complex.

Applicable ICD-10 Codes (examples listed)ICD-10

C11.0	Malignant neoplasm of superior wall of nasopharynx.
C22.0	Liver cell carcinoma.
C30.0	Malignant neoplasm of nasal cavity.
C31.0	Malignant neoplasm of maxillary sinus.
C31.1	Malignant neoplasm of ethmoidal sinus.
C31.2	Malignant neoplasm of frontal sinus.
C31.3	Malignant neoplasm of sphenoid sinus.
C31.8	Malignant neoplasm of overlapping sites of accessory sinuses.
C31.9	Malignant neoplasm of accessory sinus, unspecified.
C41.0	Malignant neoplasm of bones of skull and face.

1–10 of 23

1/3

No codes in this excerptmixed

No codes listed

Removed CPT/HCPCS CodesCPT | HCPCSNot Covered

77385	Removed from Applicable Codes
77386	Removed from Applicable Codes
G6015	Removed from Applicable Codes
G6016	Removed from Applicable Codes
G6017	Removed from Applicable Codes

Biologically effective dose threshold — Early-stage NSCLC

BED thresholdBiologically effective dose (BED) >= 105.6 Gy (RBE) was associated with improved clinical outcomes (OS, DFS, LC) in pooled hypofractionated PBT series for early-stage NSCLC.

Dose contextMedian BED delivered in pooled analysis was 105.6 Gy (RBE); studies defined hypofractionation as >= 3 Gy (RBE) per fraction.

Clinical tradeoffHigher BED (>=105.6 Gy RBE) correlated with better tumor outcomes but with increased late grade >=2 toxicity (notably rib fractures).

Evidence limitationsEvidence derived from single-arm hypofractionated series (8 studies, n=401); authors recommend further comparative studies before definitive practice change.

Prior Authorization, Documentation, and Denial Risk

Prior Authorization

Prior Authorization: demonstrate photon insufficiency

Prior authorization is required for proton beam therapy (PBT) when the request is for an indication not routinely covered or when the clinical justification must demonstrate that photon techniques cannot achieve adequate normal‑tissue sparing. The request should include a comparative plan or summary showing why IMRT/VMAT/SBRT or other advanced photon techniques are insufficient to meet organ‑at‑risk (OAR) dose constraints for the individual member.

Prior authorization must include documentation comparing PBT and photon-based plans (IMRT/VMAT/SBRT) for the specific patient.
If IMRT/VMAT is guideline-preferred (e.g., many head & neck, esophageal, or thoracic cases), documentation must explain why those photon techniques cannot meet OAR constraints before PBT is authorized.

Documentation Required

Justification and multidisciplinary documentation

Requests for PBT should include a clear, multidisciplinary justification. Relevant documentation includes tumor histology, stage/grade, tumor site and relationship to nearby critical structures, prior treatments (surgery, chemotherapy, prior RT), and an explicit dosimetric rationale that addresses why photon techniques cannot provide equivalent normal tissue sparing.

Background and Rationale

Proton beam therapy uses charged protons to deposit the majority of dose at a finite depth and then stop abruptly — the Bragg peak effect — which reduces exit dose and can spare normal tissues beyond the target. This dosimetric property underlies the rationale for PBT in anatomically challenging tumors adjacent to critical structures and in reirradiation scenarios where minimizing dose to previously irradiated normal tissues is important.

Definitions and Terminology

Base of Skull Tumors — definition

DefinitionLesions arising in the anatomically complex skull base region including the anterior cranial fossa, clivus, petrous bone, middle cranial fossa, cavernous sinus, and infratemporal fossa.

Included structuresHouses essential endocrine, neurological, and vascular components (e.g., pituitary region, cranial nerves, cavernous sinus).

Common tumor typesIncludes chordomas and chondrosarcomas as commonly cited examples.

Policy noteNewly added definition in the revised policy to support coverage criteria for skull-base indications.

Definitive Therapy — definition

DefinitionRadiation treatments delivered with curative intent (aiming to eliminate disease and achieve full recovery while maintaining quality of life).

Policy Summary

PayerUnitedHealthcare

PolicyProton Beam Radiation Therapy

Policy CodePolicy CS105.U

Change TypeMultiple material additions and revisions (indications addeddocumentation and coding updates)

Effective DateMay 1, 2026

Next Review DateN/A

Key ActionSubmit prior authorization with documentation that photon techniques cannot achieve required normal-tissue sparing and include prior radiation history for reirradiation cases.

SourceLink

On This Page

Use of PBT for lung cancer should preferably be performed within clinical trials or registries when evidence is limited, and institutions should document quality assurance measures and experience level.

Evidence of multidisciplinary team (MDT) involvement (e.g., tumor board note) when applicable.
Summary of prior therapies and timelines, especially prior radiation doses and fields for reirradiation requests.
Comparative dosimetry or physics report showing OAR dose reductions achievable with PBT and why photon plans fail to meet constraints.

Prior Authorization

Indication‑specific prior authorization requirement

Prior authorization is indication‑specific. For covered indications (see policy proven list) provide indication‑specific justification (e.g., for mediastinal lymphoma: show cardiac and breast dose reduction; for CNS tumors: proximity to optic apparatus/brainstem). For requests outside proven indications, case‑by‑case exception review requires stronger documentation of photon insufficiency and comparative planning.

Indication-specific rationale and supporting citations or guideline references where available.
For unlisted indications, include individualized risk/benefit discussion and comparative plans.

Prior Authorization

Esophageal cancer — prior authorization trigger

For esophageal or esophagogastric junction cancers, prior authorization should be triggered when dose reduction to OARs (e.g., heart, lungs) is clinically necessary and cannot be achieved with 3D‑CRT or advanced photon techniques. Where available, consider enrollment in clinical trials per guideline recommendations.

Provide comparative dosimetry showing OAR dose differences between photon planning and PBT.
Note whether the request is for trial participation (NCCN prefers clinical‑trial context when data are evolving).

Prior Authorization

PBT prior authorization justification

To approve PBT, documentation must explicitly state that OAR dose reduction cannot be achieved with standard photon techniques and include references to applicable guideline support when possible. Comparative plan data or a physics summary is expected to demonstrate the dosimetric advantage and expected clinical benefit of PBT for the patient.

Comparative planning report (dose‑volume histograms, equivalent dose metrics) or physics narrative.
Citations to guidelines (NCCN, ASTRO, specialty societies) when they recommend PBT for the specific scenario.

Prior Authorization

Prior authorization for advanced RT techniques

When advanced RT techniques or specialized simulation are required (for example, 4D CT, PET/CT-based simulation, motion management, image guidance), prior authorization should document that these technologies will be used and why they are necessary to deliver curative RT safely.

List of planned simulation and motion‑management techniques (4DCT, breath‑hold, gating) and image guidance (IGRT) to be used.
Statement that advanced techniques are indicated to limit normal‑tissue toxicity and to safely deliver the prescribed dose.

Billing Rule

Prior Authorization and Applicable Codes

Applicable CPT/HCPCS coding changes may affect prior authorization workflows. Providers should ensure coding reflects current practice and be aware that removal of certain planning codes may change how services are reviewed. Include encounter dates and procedure codes in the submission.

Ensure submitted codes match services performed; removed codes (e.g., historical CPT/HCPCS referenced in policy history) may no longer be appropriate.
Include relevant procedure codes, simulation and planning codes, and dates of service in prior‑auth documentation.

Denial Risk

Documentation insufficiency

Incomplete or missing documentation may lead to denial. Ensure prior treatment records, comparative plans, MDT notes, and prior radiation details (for reirradiation) are provided. Lack of clear evidence that photon techniques are inadequate is a common deficiency.

Insufficient records (missing prior RT details, absent comparative planning) are frequent denial reasons.
Provide full medical records, operative reports, prior RT dose/fields, and timelines for reirradiation requests.

Documentation Required

AVM intervention vs conservative management

For intracranial arteriovenous malformations (AVMs), the ARUBA trial found higher risk of death or dependency with interventional therapy versus conservative management for unruptured AVMs at 1 year; this should inform decision‑making and documentation when interventional RT is proposed.

If interventional RT is requested for an unruptured AVM, document rationale addressing ARUBA findings and why intervention is favored over conservative management.
Provide VA/neurosurgery/radiosurgery multidisciplinary discussion notes when intervention is recommended.

Denial Risk

Eligibility‑documentation risk

Failure to document key eligibility elements (tumor site, histology, stage/grade, relationship to OARs, prior treatments) increases the risk that the request cannot be approved. Requests missing subgroup evidence or tumor/prior treatment details may be returned or denied.

Include tumor histology, stage/grade, exact anatomic location relative to OARs, and prior treatment history.
For population subgroups lacking evidence, provide stronger individualized justification and comparative dosimetry.

Denial Risk

Potential denial triggers

Requests may be denied when advanced photon therapy (IMRT/VMAT/3D‑CRT/SBRT) can meet OAR constraints or when the expected PBT advantage is not demonstrated. Reirradiation requests lacking prior RT dose/field information or overlap assessment are also frequent denial triggers.

Common denial triggers: absence of comparative planning, photon techniques able to meet constraints, missing prior RT history for reirradiation.
Provide explicit demonstration that photon approaches cannot meet constraints to avoid denial.

Note

Bladder cancer guideline context

Guidelines for muscle‑invasive bladder cancer strongly discourage RT alone as curative therapy; PBT should not be requested as a single‑modality curative approach in this setting without supporting multimodality treatment documentation and strong rationale.

If PBT is requested as part of bladder‑preserving trimodality therapy, include documentation of maximal TURBT, chemotherapy plan, and rationale for proton use.
Avoid PBT as sole curative therapy for muscle‑invasive bladder cancer absent guideline‑based multimodality treatment.

Denial Risk

Potential basis for denial if not justified

If a request lacks guideline‑based justification or comparative dosimetry showing photon insufficiency, it may be denied. Decisions should reference whether IMRT or other photon techniques are capable of meeting the required OAR dose constraints.

Explain why guideline‑preferred photon techniques are inadequate when applicable.
Attach DVH comparisons or physics narrative demonstrating unmet photon constraints.

Denial Risk

Combined‑modality therapy unsupported

Combined‑modality plans that mix PBT and IMRT in a single treatment plan are unsupported by evidence and may be a basis for denial. If multiple modalities are proposed sequentially, provide clear rationale and planning justification.

Do not submit single integrated plans combining PBT and IMRT; if sequential or hybrid approaches are proposed, include clinical rationale and separate planning documentation.
Combined PBT+IMRT within one plan is not supported by current evidence.

Documentation Required

Required Medical Records for Re‑irradiation

For reirradiation requests, include prior radiation dose, date(s) of prior therapy, dose distribution/fields, time since prior treatment, extent of overlap with proposed fields, and justification for additional RT to the same site. Missing these elements commonly leads to denial.

Submit prior RT records (doses in Gy and RBE where applicable), treatment dates, and prior field diagrams or isodose maps.
Provide rationale for reirradiation, anticipated cumulative doses to critical structures, and measures to mitigate toxicity.

Documentation Required

Reirradiation documentation

Reirradiation requests should also document interval since prior RT, performance status, expected benefit, and comparative plans showing why photon re-treatment would be inadequate to meet constraints or avoid excess cumulative dose to OARs.

Clarify time since prior RT and overlapping isodose regions.
Provide expected dosimetric advantage of PBT and predicted toxicities with and without PBT.

Documentation Required

Supporting clinical documentation

Supporting clinical documentation can strengthen an exception request: cite relevant trials, systematic reviews, guideline recommendations, expected toxicity rates, and patient‑reported outcome data when available to contextualize the anticipated benefit of PBT.

Attach pertinent clinical evidence (RCTs, meta‑analyses, guideline excerpts) that apply to the specific indication.
Include expected acute and late toxicity profiles and quality‑of‑life considerations where available.

Documentation Required