Comparison of the Therapeutic Effects of Methylprednisolone and Dexamethasone on Peritumoral Edema During Radiotherapy for Brain Metastases:

This study is a multicenter, open label, randomized controlled, adaptive phase II/III seamless design clinical trial aimed at comparing the efficacy and safety of methylprednisolone (MP) and dexamethasone (DEX) in the treatment of peritumoral edema in patients with brain metastases during radiotherapy. The research plan includes brain metastasis patients aged 18-75 years, with KPS scores of 40-80, who plan to undergo whole brain radiotherapy or stereotactic radiotherapy. They will be randomly divided into MP group (40-60 mg/day) or DEX group (8-12 mg/day) in a 1:1 ratio, and medication will be continued until the end of radiotherapy, followed by gradual reduction and cessation within one week. The study is divided into two stages: the first stage (stage II exploration) includes 120 cases to preliminarily evaluate the efficacy and safety, and provide a basis for re estimating the sample size in the second stage; The second stage (Phase III confirmation) will expand the sample size based on the results after analysis during the transition period, with a total sample size of no more than 400 cases. The primary endpoint was the change in KPS score and the incidence of grade ≥ 2 hormone related adverse reactions within one week after radiotherapy. Secondary endpoints include cerebral edema index, cognitive function, quality of life, radiotherapy interruption rate, neurotoxicity, survival, and serum biomarkers (IL-6, S100B). The study is supervised by an independent data security monitoring committee and uses statistical methods such as stratified block randomization and mixed effects models to ensure the scientific and ethical compliance of the data. This study is expected to provide high-level evidence-based basis for hormone selection during the perioperative radiotherapy period for patients with brain metastases, and optimize clinical practice.