Flash Radiotherapy Against Cancer
Radiotherapy, an essential treatment for 50-60% of cancer patients, represents a powerful weapon against cancer. This therapeutic approach relies on the use of ionizing radiation directed at the tumor to destroy diseased cells while minimizing damage to surrounding healthy tissue. We discuss this with Leonida Gizzi, leader of Spoke 1 of THE and Head of the Pisa site of the National Institute of Optics (CNR).
Flash Radiotherapy.
Since its inception, the effectiveness of radiotherapy has been limited by toxicity to healthy tissues. Reducing such toxicity would enable higher doses to be administered, expanding treatment options for resistant or locally advanced tumors while decreasing long-term side effects.
A revolution in this field comes with FLASH Radiotherapy, an innovative technique that delivers high doses of radiation (5-10 Gy) in extremely short times, under 100 milliseconds, with dose rates over 400 times higher than conventional radiotherapy. This approach, still in preclinical and clinical trials, has been shown to significantly reduce radiobiological damage to healthy tissues while maintaining high effectiveness against tumors. This ability to differentiate damage between healthy tissue and tumors represents a groundbreaking advance, opening new opportunities to treat radioresistant cancers and to safely expand irradiated volumes.
Advances in Laser Technology.
One of the most promising technologies for FLASH radiotherapy involves state-of-the-art lasers. These lasers, whose inventors were awarded the 2018 Nobel Prize in Physics, enable plasma acceleration, an innovative process that generates high-energy electrons. At the CNR in Pisa, in collaboration with the Pisa Multidisciplinary Center for FLASH Radiotherapy, researchers are developing experimental systems capable of accelerating electrons with the precision and stability required for modern radiotherapy.
This technology uses extremely powerful laser pulses to create plasma capable of accelerating particles to very high speeds, considered one of the most promising solutions for delivering deep treatments safely. Moreover, it overcomes the limitations of conventional accelerators, making FLASH radiotherapy viable even for tumors in hard-to-reach areas.
Current Status and Technological Challenges.
The first evidence of the FLASH effect dates back to 2014, but many of the mechanisms underlying this phenomenon remain unclear. Preclinical research focuses on tissue mapping to identify where the effect is most effective and on defining clinical protocols to ensure the long-term safety of treatments. Simultaneously, early clinical trials are underway to validate laboratory findings and ensure statistically significant efficacy assessments.
From a technological perspective, implementing FLASH radiotherapy requires a multidisciplinary effort involving physicists, radiation oncologists, biologists, and chemists. Conventional hospital accelerators cannot currently generate the radiation beams required for these performances. However, facilities such as the Pisa Multidisciplinary Center for FLASH Radiotherapy Research and Clinical Implementation—collaborating with the University of Pisa, CNR, and INFN—are working on machines capable of delivering treatments at depth, overcoming one of the main current technological limitations.
Prospects and Clinical Impacts.
The introduction of FLASH radiotherapy could redefine the paradigm of modern radiotherapy by improving treatment effectiveness and significantly reducing side effects. It also offers a unique perspective for treating challenging cancers, such as radioresistant tumors. The success of this technique will depend on securing funding and resources to further develop the technologies and biological knowledge needed for full clinical implementation.
In Tuscany, Spoke 1 of the Tuscany Health Ecosystem (THE) is at the forefront of this challenge. Through a synergy of research, technology, and clinical applications, the project aims to strengthen Tuscany’s role in the international landscape of cancer research and innovation.
