Magnetic Resonance-guided Adaptive Stereotactic Body Radiotherapy for Hepatic Metastases

Inclusion Criteria: * confirmed underlying solid malignant tumor (no germ cell tumor, leukemia, lymphoma) * 1-3 hepatic metastases confirmed by pre-therapeutic MRI * indication for SBRT of 1-3 hepatic metastases * maximum diameter each hepatic metastasis ≤ 5 cm (in case of 3 metastases: sum of diameters ≤ 12 cm) * age ≥ 18 years of age * Karnofsky Performance Score ≥ 60% * ability to lie still on the radiotherapy treatment couch for at least one hour * ability to hold one's breath for more than 25 seconds * for women with childbearing potential, adequate contraception * ability of subject to understand character and individual consequences of the clinical trial * written informed consent (must be available before enrolment in the trial) Exclusion Criteria: * refusal of the patients to take part in the study * patients with primary liver cancer (eg. HCC, CCC) * patients after liver transplantation * impairment of liver function to an extent contraindicating radiotherapy (to the discretion of the treating radiation oncologist) * active acute hepatic/biliary infection (e.g. hepatitis, cholangitis, cholecystitis) * previous radiotherapy of the hepatobiliary system, if previous and current target volumes overlap MAESTRO Study Studienprotokoll Seite 25 von 54 Version 1.0 vom 17.12.2020 * patients who have not yet recovered from acute toxicities of prior therapies * claustrophobia * pregnant or lactating women * contraindications against performing contrast-enhanced MRI scans (pacemakers, other implants making MRI impossible, allergy to gadolinium (GD)-based contrast agent) * participation in another competing clinical study or observation period of competing trials