This prospective observational study evaluates the safety and effectiveness of stereotactic body radiotherapy (SBRT) for liver tumors, liver metastases, and pancreatic tumors. The study focuses on systematic monitoring and optimization of the SBRT treatment process, including adherence to the implemented protocol, with the aim of simplifying methods while maintaining treatment safety.

Stereotactic body radiotherapy (SBRT) is an advanced radiotherapy technique that enables delivery of high radiation doses to tumors with high precision while limiting exposure of surrounding healthy tissues. This study prospectively follows patients treated with SBRT for primary liver tumors, liver metastases, and pancreatic tumors at the Institute of Oncology Ljubljana.

The primary aim is to monitor and optimize all steps of the SBRT workflow, including protocol adherence, in order to ensure safe implementation and to evaluate treatment outcomes. The study also aims to assess whether the established SBRT protocol can be simplified without compromising patient safety.

Treatment safety and effectiveness outcomes will be evaluated during follow-up, and the collected data will be used to support further refinement of SBRT procedures for upper gastrointestinal tumors

Inclusion Criteria:

• Age ≥ 18 years
• Patients with liver tumors, liver metastases, or pancreatic tumors eligible for stereotactic body radiotherapy (SBRT)
• Planned treatment with SBRT according to institutional protocol
• Ability to comply with treatment and follow-up procedures
• Signed informed consent

Exclusion Criteria:

• Contraindications for SBRT according to institutional radiotherapy protocol
• Prior radiotherapy that prevents safe SBRT delivery to the target region
• Severe uncontrolled comorbidities preventing safe SBRT treatment
• Pregnancy
• Inability to provide informed consent or comply with study procedures