Prostate cancer is one of the areas where particle therapies (proton and heavy ion) have the most mature evidence worldwide. Japanese centers such as QST hold decades of experience.
Heavy ion and proton therapies are evaluated as alternatives to surgery, with precision aimed at protecting the rectum and urinary tract.
Treatment is usually planned as short courses over a few weeks.
Published patient series report long-term local control; what applies to you is determined by your stage and risk group.
All options including active surveillance in early stages should be discussed; the decision belongs to the urology and radiation oncology board.