ModifiedUnitedHealthcarePolicy CS179LA.D

Radiation Therapy: Fractionation, Image-Guidance, and Special Services (for Louisiana Only)

Defines medical necessity, limits, and coding guidance for fractionation schedules, image-guided radiation therapy (IGRT), and special radiation services for members in Louisiana receiving external beam radiation therapy and related procedures.

Policy Summary

PayerUnitedHealthcare

PolicyRadiation Therapy: Fractionation, Image-Guidance, and Special Services (for Louisiana Only)

Policy CodePolicy CS179LA.D

Change TypeMaterial: IGRT scope expandedBreast EBRT fractionation updated

Effective DateJun 1, 2025

Next Review Date

Key ActionProvide documentation (comparison plans/DVHs, immobilization tolerance, target motion evidence, or rationale for smaller CTV margins) when requesting IGRT with 3D-CRT for a condition not otherwise listed.

SourceLink

POLICY UPDATE CHANGES

Added language to indicate IGRT may be medically necessary during Definitive Treatment when used with three-dimensional conformal radiation therapy (3D-CRT) for a condition not listed when documentation is provided showing specified justifications (e.g., clinically significant DVH difference with DIBH vs free breathing, inability to tolerate immobilization, significant target motion, or need for smaller CTV margins).

Revised list of medically necessary services when providing EBRT for breast adenocarcinoma; added delivery of up to 5 fractions for accelerated partial breast irradiation (APBI).

Added definition of 'Definitive Treatment'.

up to 10palliative EBRT (bone) fractions allowed

up to 5APBI fractions allowed

up to 35

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LA-NSCLC fractions allowed

up to 28prostate standard fractions

240-340 cGyhypofractionation size

18% vs 9%retreatment rate (8 Gy x1 vs 30 Gy x10)

Coverage Criteria

Bone Metastases

Bone Metastases — Palliative EBRT — Covered when ONE of the following is met:

Delivery of up to 10 fractions of radiation therapy.
Delivery of greater than 10 fractions for the treatment of a site that has previously received radiation therapy.

Breast Adenocarcinoma

Breast Adenocarcinoma — EBRT — Covered when ONE of the following fractionation schemes applies:

Delivery of up to 5 fractions for accelerated partial breast irradiation (APBI).
Delivery of up to 21 fractions (inclusive of a boost to the tumor bed).
Up to 33 fractions
- Delivery of up to 33 fractions (inclusive of a boost to the tumor bed).
- - Treatment of supraclavicular and/or internal mammary lymph nodes.
  - Post-mastectomy radiation therapy.
  - Individual has received previous thoracic radiation therapy.
  - Individual has a connective tissue disorder such as lupus or scleroderma.

Locally Advanced Non-Small Cell Lung Cancer

Locally Advanced Non-Small Cell Lung Cancer — EBRT — Covered when ALL of the following are met:

Locally Advanced NSCLC

Delivery of EBRT, with or without chemotherapy, prescribed to a maximum of up to 35 fractions (i.e., 60–70 Gy range consistent with guideline-recommended definitive regimens delivered in standard 2 Gy fractions).
Fractionation and dose selection consistent with guideline recommendations for definitive curative-intent chemoradiation (e.g., recommend 60 Gy in 30 fractions or similar curative regimens).

Prostate Adenocarcinoma

Prostate Adenocarcinoma — EBRT — Covered when ONE of the following applies:

Delivery of up to 20 fractions for Definitive Treatment in an individual with Limited Metastatic Disease.
Delivery of up to 28 fractions for localized prostate cancer (moderate hypofractionation regimens consistent with guideline-recommended options).
Up to 45 fractions
- Delivery of up to 45 fractions for localized prostate cancer.
- - Individual with high-risk prostate cancer is undergoing radiation treatment to pelvic lymph nodes.

Image-Guided Radiation Therapy (IGRT)

Image-Guided Radiation Therapy (IGRT) — IGRT is medically necessary when ANY of the following indications are met:

IGRT Indications

When used with intensity modulated radiation therapy (IMRT) (e.g., prostate cancer).
When used with proton beam radiation therapy (PBRT).
When the target has received prior radiation therapy or abuts a previously irradiated area.
When implanted fiducial markers are being used for target localization.
When used with 3D-CRT during Definitive Treatment for specific conditions

Palliative Bone Metastases

Palliative radiotherapy for bone metastases — Covered when using guideline-recommended conventional palliative regimens for symptomatic bone metastases:

Palliative Bone Metastases Regimens

Single-fraction regimen: 800 cGy (8 Gy) in 1 fraction — recommended for symptomatic bone metastases.
Short fractionated regimens: 2,000 cGy in 5 fractions or 2,400 cGy in 6 fractions.
Longer fractionated regimen: 3,000 cGy in 10 fractions — appropriate in select contexts such as postoperative treatment or when indicated by ESTRO/ACROP or for spinal cord compression management.
For spine metastases causing cord or cauda equina compression (when not a surgical candidate): 800 cGy in 1 fraction, 1,600 cGy in 2 fractions, 2,000 cGy in 5 fractions, or 3,000 cGy in 10 fractions as appropriate.

Breast Radiotherapy Fractionation

Adjuvant and whole-breast radiotherapy fractionation (early breast cancer) — Covered when evidence-based fractionation schedules are used for appropriate early-stage breast cancer patients:

Whole-breast/Adjuvant Fractionation

Hypofractionated whole-breast regimens such as 40 Gy in 15 fractions or 42.5 Gy in 16 fractions as recommended by START trials, NCCN, NICE, and ASTRO guidance.
Ultra-hypofractionated whole-breast regimens of 26 Gy or 27 Gy in five fractions for selected patients consistent with trial evidence (e.g., FAST-Forward) where appropriate setup, motion management, and image verification are used.
Boost doses where indicated for higher local recurrence risk (typical boosts 10–16 Gy in 4–8 fractions) consistent with guideline recommendations.

Partial Breast Irradiation (PBI)

Partial breast irradiation (PBI) — Covered for appropriately selected patients with early-stage breast cancer when evidence-supported regimens are used:

Partial Breast Irradiation

External beam PBI: 30 Gy in 5 once-daily fractions delivered on nonconsecutive days within two weeks (recommended external-beam APBI schedule).
External beam PBI alternative: 4005 cGy in 15 once-daily fractions over three weeks per guideline recommendations.
APBI delivered with appropriate techniques such as 3D-CRT, IMRT, or brachytherapy in patients who meet selection criteria from guideline-based sources.

Breast Radiation Therapy — Evidence-supported Fractionation

Breast RT — evidence-supported fractionation — Breast cancer RT coverage supported when evidence-based hypofractionated regimens or guideline-recommended techniques are used:

Breast RT Evidence

Hypofractionated WBI (e.g., 40 Gy in 15 fractions) supported by long-term trial data (START trials, FAST-Forward, UK trials).
Five-fraction schedules (e.g., 26 Gy in 5 fractions) for selected patients as supported by randomized trial evidence with appropriate imaging verification and motion management (DIBH when indicated).
Use of DIBH and IGRT where needed to reduce cardiac dose for left-sided breast cancers and when comparison plans/DVHs show clinically significant sparing.

Stage III Non-Small Cell Lung Cancer — Definitive Radiotherapy

Stage III NSCLC — definitive RT — Locally advanced (stage III) NSCLC — coverage supported for guideline-recommended curative chemoradiation when ALL of the following are met:

Stage III NSCLC Definitive RT

EBRT delivered as definitive curative-intent chemoradiation to doses consistent with guidelines (commonly 60 Gy in 30 fractions or similar regimens totaling 60–70 Gy given with concurrent chemotherapy).
Fractionation limited to up to 35 fractions for the intents described in this policy (delivery greater than 35 fractions is not medically necessary).
Use of IGRT and motion management as clinically indicated to safely deliver curative RT when OARs are in close proximity or when complex motion management is required.

Prostate Radiation Therapy — Fractionation and Pelvic Nodes

Prostate RT — fractionation and pelvic nodal considerations — Localized prostate cancer — coverage stance based on risk and evidence for hypofractionation and pelvic nodal treatment:

Prostate RT Fractionation and Nodes

Moderate hypofractionation regimens such as 60 Gy in 20 fractions (3 Gy/fraction) for localized prostate cancer are medically necessary and supported by randomized evidence.
Conventional fractionation regimens (e.g., 74–78 Gy in 37–39 fractions) remain appropriate options based on patient and provider judgment.
Pelvic nodal and high-risk considerations
- - High-risk prostate cancer with elective pelvic nodal radiation (contemporary doses to nodes ~45–52 Gy).

Guideline-based Coverage Considerations

Guideline-based coverage considerations — Consider treatment approaches consistent with specialty guideline recommendations:

label":"Guideline-based Considerations"}

COVERAGE CRITERIA — IGRT

COVERAGE CRITERIA — IGRT is supported and may be medically necessary in these contexts per professional society guidance and policy revision:

IGRT Coverage Contexts

IGRT with 3D-CRT, IMRT, PBRT, or external beam-based APBI when targets are near critical structures or when small margins, motion management, or dose escalation are required.
Daily image guidance recommended for conventionally fractionated or hypofractionated treatments in specific disease sites per ASTRO and NCCN (e.g., pancreatic cancer, hepatocellular carcinoma, oligometastatic NSCLC, soft tissue sarcoma).
IGRT may be medically necessary during Definitive Treatment with 3D-CRT for a condition not listed when documentation shows clinically significant DVH differences with DIBH, inability to tolerate immobilization, significant target motion, or need for smaller CTV margins than traditionally used for 3D-CRT.

Coding and Billing Guidance

Referenced CPT/HCPCS Codes and descriptionsmixed

77014	Computed tomography guidance for placement of radiation therapy fields.
77301	IMRT planning (includes special dosimetry).
77331	Special dosimetry (e.g., TLD, microdosimetry) (specify).
77370	Special medical radiation physics consultation.
77385	IMRT delivery, simple (includes guidance/tracking).
77386	IMRT delivery, complex (includes guidance/tracking).
77387	Guidance for localization of target volume for delivery of radiation treatment (intrafraction tracking).
77399	Unlisted procedure, medical radiation physics, dosimetry and treatment devices, and special services.
77401	Radiation treatment delivery, superficial and/or orthovoltage, per day.
77402	Radiation treatment delivery, >=1 MeV; simple.

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Referenced G-codesHCPCS

G6001	Ultrasonic guidance for placement of radiation therapy fields.
G6002	Stereoscopic x-ray guidance for localization of target volume for delivery of radiation therapy.
G6003	Radiation treatment delivery, single treatment area, simple, up to 5 MeV. (Not on LA fee schedule.)
G6015	Intensity modulated treatment delivery, single or multiple fields/arcs (not on LA fee schedule).
G6017	Intra-fraction localization and tracking of target or patient motion during delivery of radiation therapy (per fraction).

No explicit CPT/HCPCS/ICD codes in these chunksmixed

No codes listed

Dose-fractionation examples (clinical, not billing codes)mixed

No codes listed

Applicable CPT guidance and notationsCPT

77401	Superficial radiation therapy; notation added that megavoltage treatment delivery codes should not be reported when 77401 is provided.
77261	Not to be reported with 77401 per updated notation.
77262	Not to be reported with 77401 per updated notation.
77263	Not to be reported with 77401 per updated notation.
77332	Not to be reported with 77401 per updated notation.
77333	Not to be reported with 77401 per updated notation.
77334	Not to be reported with 77401 per updated notation.
77306	Not to be reported with 77401 per updated notation.
77307	Not to be reported with 77401 per updated notation.
77316	Not to be reported with 77401 per updated notation.

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Hypofractionation fraction size — 240-340 cGy

Hypofractionation fraction sizeDefined as EBRT with fraction size between 240 cGy and 340 cGy.

Lower bound240 cGy per fraction.

Upper bound340 cGy per fraction.

Retreatment/retreatment rate difference — Retreatment rate higher with single 8 Gy (e.g., 18% vs 9% in Hartsell trial)

Retreatment rate difference (Hartsell trial)Retreatment rate higher with single 8 Gy: 18% (single 8 Gy) vs 9% (30 Gy in 10 fractions).

Overall response at 3 months

Provider Actions and Documentation Requirements

Prior Authorization

IGRT with 3D‑CRT may be medically necessary with documentation

Image-guided radiation therapy (IGRT) used with 3D-conformal radiation therapy (3D-CRT) may be considered medically necessary for conditions not otherwise listed when adequate documentation supports one or more of the specified justifications (e.g., clinically significant normal-tissue sparing demonstrated by comparison plans/DVHs, inability to tolerate immobilization during CT simulation, documented significant target motion, or need for smaller CTV/PTV margins than traditionally used for 3D-CRT).

When IGRT with 3D-CRT is claimed for a condition not listed as medically necessary, submit comparison treatment plans and dose-volume histogram (DVH) evidence when available.
If immobilization intolerance is claimed, include simulation notes and objective documentation of failed immobilization attempts.
If significant target motion is claimed, include imaging evidence (motion studies, 4DCT, cine imaging) documenting motion amplitude/frequency.
If reduced CTV/PTV margins are claimed, include QA documentation supporting system geometric accuracy and rationale for margin reduction.

Note

No step therapy algorithms described

Definitions

Limited Metastatic Disease definition

Core definitionLimited Metastatic Disease (applicable to prostate cancer): absence of visceral metastasis or fewer than four bone metastases with no metastasis outside the vertebral bodies or pelvis.

ScopeDefinition is applied in policy contexts that permit Definitive Treatment for limited metastatic disease.

Source referencesDefinition cited from Parker et al., 2018 and policy definitions section.

Definitive Treatment — Radiation treatments for cancer with curative intent.

DefinitionDefinitive Treatment: Radiation treatments for cancer with curative intent.

ContextDefinition added to the policy to clarify when IGRT or other techniques are being used with curative intent.

Background

External beam radiation therapy (EBRT) includes three‑dimensional conformal radiation therapy (3D‑CRT), intensity‑modulated radiation therapy (IMRT), and proton beam radiation therapy (PBRT); EBRT may be delivered with curative (definitive) or palliative intent. Image‑guided radiation therapy (IGRT) refers to imaging performed at or near the time of treatment (for example, cone‑beam CT or MVCT) to localize targets and correct positional uncertainties prior to dose delivery. The policy aligns with professional guidance that IGRT is indicated when targets are adjacent to critical structures, subject to internal or daily motion, abut previously irradiated areas, require narrow margins to protect nearby organs, or when delivering highly conformal or dose‑escalated treatments. Quality assurance and documented CT‑based IGRT system accuracy are emphasized as critical when margins are reduced.

Revision History

2025-06-01Revised coverage/medical necessityLatest

Revised medically necessary services for EBRT for breast adenocarcinoma to add delivery of up to 5 fractions for accelerated partial breast irradiation (APBI).

2025-06-01Added medical necessity language

Added policy language indicating IGRT may be medically necessary during Definitive Treatment when used with 3D-CRT for conditions not listed if documentation demonstrates specified justifications (e.g., DVH comparison showing clinically significant normal tissue sparing, inability to tolerate immobilization during CT simulation, significant target motion, or need for smaller CTV margins).

Policy Summary

PayerUnitedHealthcare

PolicyRadiation Therapy: Fractionation, Image-Guidance, and Special Services (for Louisiana Only)

Policy CodePolicy CS179LA.D

Change TypeMaterial: IGRT scope expandedBreast EBRT fractionation updated

Effective DateJun 1, 2025

Next Review Date

SourceLink

On This Page

Radiation therapy is delivered post-prostatectomy (salvage/adjuvant setting).

Individual has a history of inflammatory bowel disease such as ulcerative colitis or Crohn's disease.

Individual has received previous pelvic radiation therapy.

Accelerated partial breast irradiation (APBI).

Breast boost with the use of photons.

Hypofractionated radiation therapy delivered up to five fractions to the whole breast or chest wall.

Individual is being treated in prone position.

Left breast cancer and deep inspiration breath hold (DIBH) technique is being used.

During boost treatment of rectal and bladder cancer.

Head and neck cancer.

Hepatobiliary cancer.

Soft tissue sarcoma.

IGRT with 3D-CRT may be medically necessary for other conditions when documentation shows one or more of the following

Clinically significant difference in normal tissue sparing between DIBH and free breathing as documented by comparison plans and dose-volume histogram (DVH).
Member unable to tolerate immobilization during computed tomography (CT) simulation.
Significant target motion as documented by imaging.
Smaller clinical target volume (CTV) margins are required than what is traditionally used for 3D-CRT.

Reirradiation: conventional palliative RT regimens such as 800 cGy in 1 fraction, 2,000 cGy in 5 fractions, 2,400 cGy in 6 fractions, or 2,000 cGy in 8 fractions for spine; for symptomatic nonspine metastases reirradiation may use single-fraction (800 cGy) or multifraction regimens (2,000 cGy in 5 fractions or 2,400 cGy in 6 fractions).

Post-prostatectomy radiation therapy (adjuvant or salvage) where expanded fields may be used.

History of prior pelvic radiation or inflammatory bowel disease prompting altered fractionation/field decisions.

66% overall response rate reported across arms.

Acute toxicity comparisonAcute grade 2-4 toxicity more frequent with 30 Gy in 10 fractions (17%) vs 8 Gy single fraction (10%).

Hypofractionation fraction size range — Moderate hypofractionation defined up to ~3.4 Gy per fraction

Moderate hypofractionation upper limitDefined in trials and guidelines up to approximately 3.4 Gy per fraction.

Example regimen — 3.4 Gy fractionsHYPRO trial evaluated 3.4 Gy x 19 fractions (did not show superiority and had higher acute GI toxicity).

Guideline-supported examplesASTRO/NCCN cite regimens such as 3 Gy x 20, 2.7 Gy x 26, 2.5 Gy x 28 as examples within moderate hypofractionation ranges.

Intrafraction motion margin lower limit — 2 mm

Intrafraction motion margin lower limitStudy-derived lower limit margin to account for intrafraction prostate motion: 2 mm.

Observed motion frequencyIn 66% of treatment fractions motion outside 2 mm was observed; 28% outside 3 mm.

Implication for practiceMargins of 2 mm account for intrafraction motion but larger margins may be needed for other uncertainties.

There are no explicit step-therapy algorithms or mandatory sequencing rules described in this section of the policy. Clinicians should follow guideline-recommended regimens and document rationale when deviating from standard, guideline-based fractionation or technique.

Denial Risk

High-dose RT in Stage III NSCLC risks

High-dose radiation (e.g., 74 Gy in 2 Gy fractions) delivered with concurrent chemotherapy for stage III non‑small cell lung cancer did not improve survival and was associated with increased harm in randomized trials. Use curative-intent concurrent chemoradiation regimens consistent with guideline-recommended doses (e.g., ~60 Gy in 2 Gy daily fractions) and avoid higher-than-standard doses shown to be harmful.

Reference randomized trial evidence showing worse overall survival and increased toxicity with 74 Gy versus 60 Gy given with concurrent chemotherapy.
Follow ASTRO guideline recommendation of 60 Gy in 2 Gy once-daily fractions for definitive chemoradiation in locally advanced NSCLC.

Documentation Required

Required treatment and imaging documentation

When IGRT is used or billed, provide documentation of the treatment regimen and imaging verification plan that supports medical necessity and accurate delivery. Documentation should explicitly state fractionation schedule, imaging frequency and modality used for setup verification, use of implanted fiducials if applicable, and any deviations from standard practice with supporting rationale.

Record the intended fractionation schedule (total dose and number of fractions) in the treatment plan.
Specify imaging modality and frequency for setup verification (e.g., daily kV-CBCT, MV imaging, portal films) and indicate when each fraction will be verified.
If implanted fiducials are used, document placement and how they are used for localization.
If 5‑fraction whole-breast schedules are used, include verification imaging for each fraction and corrective actions for measured displacements.

Documentation Required

Required supporting documentation for IGRT and special services

Supporting documentation required when requesting IGRT or special services (e.g., special dosimetry, medical physics consultation, or unlisted special services) must demonstrate why the additional service is necessary beyond routine planning and delivery. CPT codes for special services (e.g., 77301, 77331, 77370, 77399, 77470) are considered for coverage only when the primary radiation procedure is proven and medically necessary and when documentation justifies the extra service.

When billing CPT 77399 (unlisted), include a detailed description and rationale and why no other code applies.
For special dosimetry (CPT 77331), include description of the unusual measurement circumstances and number of measurements.
For 77370 or 77470, document the specific complex circumstances (see coding clarifications) that justify a one‑time special physics or treatment-procedure code.
Attach treatment plans, dosimetry reports, and any physician/physicist notes that support the request.

Documentation Required

IGRT QA documentation

Quality-assurance (QA) documentation for CT-based IGRT systems is expected when IGRT is used to justify reduced target margins or when claiming IGRT with 3D-CRT for nonlisted conditions. QA records should demonstrate routine geometric accuracy assessment and daily quality-control procedures appropriate to the intended use of the image-guidance system.

Provide the facility's CT‑IGRT QA protocol and evidence of implementation (daily checks, geometric accuracy tests).
Supply recent geometric accuracy assessments and corrective-action records if tolerances were exceeded.
Document how QA supports any planned reduction in PTV margins to ensure safe delivery.

Note

Preferred fractionation considerations for bone metastases

For palliative radiation to bone metastases, preferred fractionation options are limited regimens supported by evidence and guideline consensus. Policy favors limited fractionation (single or short multifraction regimens up to 10 fractions) and recognizes that single‑fraction 8 Gy, 20 Gy/5 fractions, 24 Gy/6 fractions, and 30 Gy/10 fractions are appropriate options depending on clinical context.

Preferred palliative regimens include 800 cGy in 1 fraction, 2,000 cGy in 5 fractions, 2,400 cGy in 6 fractions, or 3,000 cGy in 10 fractions (ASTRO strength: strong).
For spine metastases causing cord compression, recommended options also include 1,600 cGy in 2 fractions or 2,000 cGy in 5 fractions when surgery is not feasible.
When reirradiation is planned, follow guideline-recommended reirradiation regimens and document prior dose and interval to the prior course.

Note

Prostate nodal treatment consideration

For high‑risk prostate cancer, consider the balance between prostate-only radiotherapy and whole-pelvic radiotherapy (WPRT). Contemporary evidence supports offering prophylactic WPRT with long-term androgen deprivation therapy for patients with sufficiently high nodal risk, as it improves biochemical failure‑free survival and disease‑free survival though overall survival benefit is not proven.

When elective pelvic nodal RT is planned, document estimated nodal risk (e.g., ≥20%) and rationale for WPRT versus prostate-only RT.
Document use of IMRT/IGRT and planned duration of ADT when WPRT is selected.

Note

Salvage radiotherapy sequencing for prostate cancer

Guidance on salvage radiotherapy sequencing after radical prostatectomy should be documented in the record. Offer salvage RT when PSA is ≤ 0.5 ng/mL; for high‑risk patients clinicians may consider salvage RT at PSA < 0.2 ng/mL. When salvage RT is given with ADT, document whether regional nodes will be included.

Document the PSA value prompting salvage RT and risk features that influenced timing.
If expanded fields including regional lymph nodes are used with salvage RT and ADT, provide rationale and treatment-field details.

Note

None explicit in this section

No additional explicit provider actions are specified in this section beyond documentation, guideline-concordant fractionation, and the IGRT and QA requirements described above.

Conventional palliative RT regimens (bone metastases) — examples per ASTRO.

ASTRO/ACR-recommended conventional palliative regimensExamples include 800 cGy in 1 fraction; 2,000 cGy in 5 fractions; 2,400 cGy in 6 fractions; and 3,000 cGy in 10 fractions.

Selection considerationsRegimen choice should consider prognosis, prior RT, normal tissue risk, quality of life, and patient goals.

Reirradiation optionsFor reirradiation, recommended conventional regimens include single 800 cGy or multifraction options such as 2,000 cGy in 5 fractions or 2,400 cGy in 6 fractions.

Five-fraction breast RT — Accelerated schedules delivering 26-27 Gy in five fractions; verification imaging per fraction required.

Dose-fractionation exampleAccelerated schedules delivering 26–27 Gy in five fractions over one week (Brunt et al.).

Imaging requirementVerification imaging for each fraction is required for five-fraction whole-breast schedules with recommendations to correct measured displacements.

Comparative outcomes26 Gy in 5 fractions was non-inferior to 40 Gy in 15 fractions; 27 Gy had higher clinician-assessed normal tissue effects in some assessments.

HF-WBI / hypofractionation — Examples: 40 Gy in 15 fractions; prostate 60 Gy in 20 fractions.

HF-WBI examplesWhole-breast hypofractionation examples include 40 Gy in 15 fractions (START) and 40–42.5 Gy in 15–16 fractions per ASTRO/NCCN guidance.

Prostate hypofractionation exampleProstate hypofractionation example supported by trials: 60 Gy in 20 fractions (non-inferior in randomized trials).

APBI dosing noted by NCCNNCCN preferred RT dosing for APBI is 30 Gy in 5 fractions.

DIBH — Deep inspiration breath-hold definition.

DefinitionDeep inspiration breath-hold (DIBH): a technique used to reduce cardiac dose for left-sided breast radiotherapy.

Guideline recommendationNICE and NCCN recommend use of DIBH to reduce heart dose for left-sided disease.

Use with IGRTDIBH may be used with IGRT and DVH comparisons are recommended to evaluate normal tissue sparing.

APBI / PBI — Accelerated or partial-breast irradiation definition and example (30 Gy in 5 fractions).

DefinitionAccelerated/partial-breast irradiation (APBI/PBI): delivery of radiation to the tumor-bed region rather than the whole breast.

Example regimenExternal-beam APBI example: 30 Gy in 5 fractions (NCCN preferred dosing).

IndicationCovered for appropriately selected early-stage breast cancer patients per guideline criteria.

Moderate hypofractionation — Regimens delivering approximately 2.4 to 3.4 Gy per fraction.

Moderate hypofractionation rangeRegimens delivering approximately 2.4 to 3.4 Gy per fraction constitute moderate hypofractionation.

Example schedulesExamples include 3 Gy x 20, 2.7 Gy x 26, and 2.5 Gy x 28 as commonly cited regimens.

Guideline endorsementASTRO and NCCN support moderate hypofractionation for many patients with localized prostate cancer.

IGRT — Use of imaging at or near time of treatment (e.g., CBCT, MVCT) to localize targets and correct positional uncertainties.

IGRT definitionUse of imaging at or near the time of treatment (e.g., CBCT, MVCT) to localize targets and correct positional uncertainties prior to delivery.

PurposeLocalize targets and correct positional uncertainties to ensure accurate delivery of EBRT.

QA importanceAs PTV margins tighten, geometric accuracy assessment and daily quality-control procedures for CT-based IGRT systems are expected.

Definitive Treatment — (Policy added a definition; full wording to be sourced).

Policy definition addedDefinitive Treatment: policy added a definition indicating radiation treatments delivered with curative intent; full wording added to policy but specific extended text not present in excerpt.

Clinical contextUsed to clarify coverage and when IGRT with 3D-CRT may be medically necessary for conditions not otherwise listed, when applied during definitive (curative-intent) therapy.

Added a definition of 'Definitive Treatment' to the policy.