Ultra-high Dose Radiation for Liver Metastases

(ULTRAS Trial)

This trial explores a new method for treating liver tumors that have spread from other cancers. Researchers aim to determine if a single, very high dose of radiation using advanced technology (MR-Linac) proves more effective than the current high-dose treatment. This method, known as MR-guided Stereotactic Ablative Single-fraction, will be compared to assess tumor control and its impact on the patient's quality of life. Individuals with specific types of cancer that have spread to their liver, with up to three treatable tumors, may qualify for this study. As a Phase 3 trial, this treatment represents the final step before FDA approval, offering participants a chance to contribute to potentially groundbreaking advancements in cancer therapy.

Participants must not be receiving any other standard anti-cancer therapy or experimental agent at the same time as the trial treatment. There needs to be at least a one-week break from systemic therapy before starting the trial treatment.

Research has shown that MR-guided stereotactic ablative radiotherapy, a type of focused radiation treatment, is generally safe and well-tolerated for treating liver metastases. In past studies, this treatment effectively controlled tumors, stopping cancer growth in the treated area. Importantly, patients did not experience severe side effects. For example, one study reported no serious immediate side effects, such as radiation-induced liver disease.

Researchers are excited about these treatments because they offer a new way to target liver metastases using ultra-high doses of radiation. Unlike traditional radiation therapy, which often requires multiple sessions, these treatments use a single, precise dose guided by magnetic resonance (MR) imaging, allowing for more accurate targeting of tumors. One treatment arm uses an ultra-high dose of 38Gy, while the other uses a high dose of 27Gy, both potentially enhancing the effectiveness of destroying cancer cells without harming surrounding healthy tissue. This innovative approach could lead to faster, more effective treatment outcomes compared to conventional methods.

Studies have shown that stereotactic body radiotherapy (SBRT), which uses focused radiation to treat tumors, effectively addresses liver metastases. Previous patients experienced promising results with this method, although researchers continue to determine the optimal radiation dose. In this trial, participants will receive either an ultra-high dose or a high dose of radiation in a single session. The current hypothesis suggests that a very high dose in one session might better control tumors and cause fewer side effects. This treatment employs MR-Linac technology, combining MRI imaging with radiation to target the tumor more precisely. If successful, the ultra-high dose SBRT could improve tumor control and enhance the quality of life for patients with liver metastases.⁶⁷⁸⁹¹⁰