HMN 2025: How Modern radiotherapy delivers higher doses with fewer sessions

New research from the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) demonstrates the accuracy of modern radiotherapy techniques used to treat cancer. The study is published in the Journal of Applied Clinical Medical Physics.

The audit study helps identify when best practice is achieved, minimizing harm to healthy tissues and organs and improving treatment effectiveness.

ARPANSA’s medical physics lead and study author Dr. Andrew Alves says that as radiotherapy machines have improved, and science has advanced, doctors are prescribing fewer sessions with a more targeted, higher dose each treatment.

“Higher dose treatment, known as hypofractionated radiotherapy means fewer visits to the clinic,” Dr. Alves said.

“When the high dose radiation is on target it kills tumor cells and spares healthy organs and tissues; however, the margin for error for this approach is low. That’s why we’ve developed a customized audit to validate patient dose for this treatment.

“Using an artificial ‘patient’ (or phantom), our paper shows how Australian and New Zealand clinics are performing and when practitioners hit the target within the accepted small margins of error in position, ±2 mm, and dose ± 5%.”

Modern technology enables more precise targeting of the radiation beam to the tumor, meaning treatment is less likely to affect healthy tissue.

The study specifically looked at spine, lung, and soft tissue radiotherapy treatment accuracy.

Australian Clinical Dosimetry Service director, Rhonda Brown, had oversight of the study and emphasized its real-world application impacted long-term patient survivorship.

“Around 90,000 patients across Australia receive radiotherapy each year. There are many benefits to using hypofractionated radiotherapy—including that clinics can treat more patients because people need fewer radiation doses with this treatment approach,” Brown said.

“As the Australian Government’s primary radiation protection authority, and lead radiotherapy audit service in the country, we want to help ensure treatments are curing patients and not causing harm.

“This study looked at over 700 treatments and can be used not only as a benchmark in Australia but across the world.”

Provided by
Australian Radiation Protection and Nuclear Safety Agency (ARPANSA)