Study of MRI-guided Adaptive Stereotactic Radiotherapy Without PTV Margins for Non-Small Cell Lung Cancer Patients with Brain Metastases Compared to Conventional Radiotherapy

What this Trial Is About

Researchers are evaluating the safety and efficacy of removing planning target volume PTV margins using MRI-guided adaptive stereotactic radiotherapy SRT in patients with non-small cell lung cancer NSCLC who have brain metastases. The study compares this MRI-guided approach to conventional CT-guided stereotactic radiotherapy that includes PTV expansion margins. This phase 2 trial aims to determine if eliminating PTV margins can maintain treatment safety and effectiveness. Participants will be randomly assigned to one of two groups. The study group will receive MRI-guided adaptive SRT without PTV expansion margin, delivered once daily for five sessions with a total dose of 30Gy using an MRI-linac. The control group will receive conventional standard SRT with PTV expansion margin, also given once daily for five sessions with a total dose of 30Gy, delivered using a conventional linear accelerator. After treatment completion, patients will have regular follow-up visits to monitor outcomes. During the study, participants will undergo MRI or CT scans depending on their group, as well as evaluations of brain necrosis incidence, intracranial progression, tumor response, overall survival, and radiation-related neurotoxicity over one year. Organ and bone marrow functions will be monitored before treatment. The total participation duration includes treatment followed by systematic safety and efficacy assessments extending to one year after therapy.

Elimination of PTV Margins Based on MRI-guided Adaptive Stereotactic Radiotherapy for Non-small Cell Lung Cancer With Brain Metastasis