Stereotactic Radiotherapy in Oligometastatic Brain Disease: a Randomised Phase III Study Comparing Hypofractionated Stereotactic Radiation Therapy (3*10 Gy) to the Historical Single-dose Radiosurgery (1*20 to 25 Gy) With Medico-economic Evaluation.

Inclusion Criteria: * Patients aged ≥ 18 years * WHO performance status 0 or 1; * Patient eligible for SRT after a multidisciplinary committee decision; Patient with BMs from radioresistant cancer (renal cell carcinoma, sarcoma, melanoma) is eligible * Patient having up to 5 BM of solid tumours with an histologically proven diagnoses; patients who have had a metastasectomy and having 1 to 4 BM lesions is eligible (ANOCEF recommendations); post-operative cavity must be treated by radiosurgery according to local procedures with respect of non-inclusion criteria\* (cavity will not be analyzed for efficacy) * Presence of at least one and no more than 5 target lesions for SRT, measuring between 10 and 25 mm. In the event of synchronous BM, lesions measuring less than 10mm or more than 25mm (1 to 4 lesions) will be treated at the discretion of the investigator * Max cumulative GTV of 30cm3 * Normal complete blood count (CBC) * Absence of bleeding BM or meningeal carcinomatosis; * Symptomatic BM are allowed * DS-GPA score: * Renal cancer: DS-GPA 2,5 or more * Breast cancer: DS-GPA 2,5 or more * Melanoma: DS-GPA 1.5 or more * Gastro-instestinal (GI) cancer: DSGPA 3 or more * Adenocarcinoma lung cancer: DS-GPA 2 or more (DS-GPAmol) * Squamous lung cancer : DS-GPA 2,5 or more (DS-GPAmol) * For cancers where the DS-GPA score is not applicable, the patient is eligible if eligibility criteria are met * Patient with no concomitant systemic treatment; in case of ongoing systemic treatment, wash out period of 3-7 days before and after SRT, depending of drug and at the discretion of investigator; * Patient sufficiently cooperating to perform the treatment with the use of a thermoformed mask; * Patient whose neuropsychological abilities allow to follow the requirements of the protocol; * Female with childbearing potential must use adequate contraception * Signed informed consent formOligoBM-01 Trial - ID-RCB number: 2021-A01622-39 - version 3.1 dated from 2023-06-22 Page 9 of 51 * Patients affiliated to the social security system Exclusion Criteria: * Patients with current or past history small cell lung cancer, germ-cell tumours, lymphoma, leukemia and multiple myeloma within the last 5 years; * Patients with metastases in the brain stem, or within 1 cm of the optic apparatus; * Patients with an associated neurodegenerative disease; * Any symptoms not attributable to BM or cancer disease requiring long term corticosteroid use (regardless of dose); * Contraindication to perform the brain MRI or gadolinium or iodinated contrast; * Known hypersensitivity to the contrast product or to any their excipients * Patients with previous brain stereotactic irradiation * Whole brain irradiation history; * Haemorrhagic metastasis; * Ongoing anti angiogenic treatment (treatment should be held 3-7 days before irradiation and re-initiated 3-7 days after irradiation for patient to be eligible); * Patients with too close brain lesions for whom a treatment plan on one target metastasis delivers a dose \> 5 Gy on other concomitant metastasis ; * Patient deprived of liberty or under guardianship; * Known pregnancy or breastfeeding * Any geographical conditions, social and associated psychopathology that may compromise the patient's ability to participate in the study; * Participation in a therapeutic trial for less than 30 days. * Patient deprived of freedom or under guardianship