Study Comparing Neoadjuvant Versus Adjuvant Stereotactic Radiotherapy of Brain Metastases

Inclusion Criteria: * Patients aged 18 years and older; * Patients with 1 to 12 brain metastases on preoperative MRI, at least one of which (contrast enhancement of at least 1 cm) is accessible for the most complete possible resection (target lesion); * Patients with a Karnofsky performance score of ≥ 70; * Patients able to perform neurocognitive tests without assistance; * Patients who understand the study and agree to attend all visits; * Patients who have signed a written informed consent form; * Affiliation with a social security system. Exclusion Criteria: * Patient who has already been treated with surgery, radiosurgery, and/or radiotherapy for the target brain metastasis; * Medical contraindication to MRI; * Patient with an estimated life expectancy of ≤ 3 months; * Patients participating in another clinical trial, or who are in the exclusion period of another clinical trial; * Patients unable to complete a self-administered questionnaire; * Patients from a vulnerable population.