Adaptive Radiotherapy for Rectal Cancer

(ARBOR Trial)

This trial tests whether an extra dose of radiation, adjusted to tumor response, can enhance rectal cancer treatment and reduce side effects. After standard radiation and chemotherapy, participants receive additional radiation (adaptive radiotherapy boost) fine-tuned with MRI scans and a small balloon to protect healthy tissue. It targets individuals with specific stages of rectal cancer who have not undergone prior treatments. Participants should be comfortable with MRI scans and able to handle chemotherapy before and after the test phase. As a Phase 1 trial, the research focuses on understanding how the treatment works in people, offering participants the opportunity to be among the first to receive this innovative approach.

The trial information does not specify if you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

Research has shown that adaptive radiotherapy, which adjusts treatment using MRI scans, is generally safe for patients. Studies have found that this method carries a low risk of severe side effects, making serious negative reactions uncommon.

One study discovered that higher doses of radiation in adaptive radiotherapy have a favorable side-effect profile, indicating that most patients did not experience severe negative reactions.

Adaptive Radiotherapy Boost is unique because it personalizes radiation treatment for rectal cancer patients in a way that standard therapies do not. Traditional radiotherapy often uses a fixed plan for all patients, but adaptive radiotherapy adjusts the radiation dose and delivery based on real-time changes in the tumor and surrounding tissues. Researchers are excited about this approach because it has the potential to increase the precision and effectiveness of treatment, potentially reducing side effects and improving outcomes for patients.

Research has shown that adaptive radiotherapy, which adjusts radiation doses based on tumor response, could effectively treat rectal cancer. In this trial, participants will receive an Adaptive Radiotherapy Boost after standard pelvic chemoradiation. One study found a promising complete response rate of 27%, meaning no detectable cancer, due to higher radiation doses, with manageable side effects. This method targets aggressive cancer cells while protecting healthy tissue. By using regular MRI scans to adjust treatment, adaptive radiotherapy aims to improve accuracy and reduce unwanted side effects.⁴⁶⁷⁸⁹