Advancing Particle Therapy to Improve Cancer Care: Report on "2nd World Forum on Particle Therapy"

Area of Science:

• Oncology
• Radiation Oncology
• Medical Physics

Background:

• Charged particle therapy (PT), encompassing proton beam therapy (PBT) and carbon ion radiation therapy (CIRT), presents potential therapeutic advantages for specific cancer patient populations.
• A significant challenge in PT is broadening its accessibility to ensure maximum clinical benefit for a wider range of patients.

Purpose of the Study:

• To discuss strategies for advancing PT globally and identify key challenges and opportunities for its expansion.
• To review current evidence from PBT and CIRT trials and outline future research directions.

Main Methods:

• Convening 81 international PT leaders at the 2nd World Forum to discuss global PT advancement strategies.
• Reviewing results from recent PBT trials and ongoing CIRT trials.

Main Results:

• PBT trials have demonstrated reduced toxicity and improved outcomes in specific cancers like oropharyngeal, esophageal, and hepatocellular carcinoma, as well as leptomeningeal disease.
• Mixed results were observed in low-to-intermediate risk prostate cancer and adult glioblastoma, highlighting the need for further investigation.
• CIRT trials are ongoing, with a critical need for harmonized relative biological effectiveness (RBE) models. Exploration of helium and oxygen therapy, as well as heavy ion synergy with immunotherapy, is recommended.

Conclusions:

• Large, definitive "Champion Studies" proving survival benefit over standard therapies are essential for PT adoption.
• International collaboration, robust administrative and financial support, and efficient community efforts are vital for advancing PT and benefiting more patients.
• Future research should focus on leveraging PT's biological advantages, targeting promising sites, integrating molecular diagnostics, exploring hypofractionation, and defining the role of heavier ions and their immunomodulatory effects.