Functional Lung Avoidance Planning Guided by Lung Perfusion PET/CT Versus Anatomical Planning for Lung Stereotactic Body Radiotherapy (Pegasus 2)

Regional University Hospital Center (CHRU)

Status and phase: Not yet enrolling; Phase 3

Conditions: Lung Cancer (Diagnosis); 68Ga-MAA; Stereotactic Body Radiotherapy

Treatments: Radiation: Conventional anatomical planning radiotherapy; Radiation: Functional Lung avoidance planning

Study type: Interventional

Funder types: Other

Identifiers

NCT07289646

29BRC23.0220

Details and patient eligibility

About

Stereotactic body radiotherapy (SBRT) has an increasing role in the treatment of both primary and secondary lung tumors. However, lung SBRT remains associated with significant radiation induced lung injury (RILI). Indeed, the reported incidence of symptomatic radiation induced lung injury (grade≥2) in the published literature is up to 20%. A current challenge of lung SBRT is therefore to better preserve lung function and to reduce pulmonary toxicity.

During standard lung SBRT planning, dose constraints are defined on the anatomical lung volume. This planning considers the lung as functionally uniform and does not take into account the variability of regional lung function distribution. Functional lung avoidance is an emerging concept in lung radiotherapy (RT). The technique aims at personalizing RT treatment planning to individuals' lung functional distribution, by sparing functional pulmonary areas while prioritizing delivery of high doses to non-functional regions.

68Ga-MAA lung perfusion PET/CT is a novel imaging modality for regional lung function assessment. As compared with conventional lung scintigraphy, lung perfusion PET/CT is inherently a vastly superior technology for image acquisition (higher sensitivity and spatial resolution, greater access to respiratory gated acquisition). A more accurate lung functional mapping improves the possibility of functional lung avoidance planning for SBRT.

The hypothesis is that functional lung avoidance planning guided by 68Ga-MAA perfusion PET/CT, while delivering an optimal dose to the tumor, will reduce the frequency of RILI in patients treated with lung SBRT.

Enrollment: 418 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients aged > 18 years planned to be treated in the radiotherapy department of the participating centers with SBRT for primary or secondary lung tumors will be eligible to participate into the study

Exclusion criteria

• Inability to give informed consent
• Patientsunder guardianship or curatorship
• Pregnant or breastfeeding women.
• Contraindications to the radiolabeled product infused for lung perfusion PET/CT.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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418 participants in 2 patient groups

Control group:

Active Comparator group

Description:

A conventional anatomical planning will be performed.

Treatment:

Radiation: Conventional anatomical planning radiotherapy

Experimental group

Experimental group

Description:

functional planning will be carried out, respecting the standard constraints especially to the tumor and the anatomical lung volume, but also incorporating "lung functional volume" constraints defined by regional lung function mapping.

Treatment:

Radiation: Functional Lung avoidance planning