There is no single "most successful" treatment for prostate cancer, as the ideal therapeutic approach depends entirely on the cancer's stage, grade, patient age, overall health profile, and personal priorities regarding side effects. For localized, low-risk tumors, active surveillance offers excellent survival outcomes without treatment morbidity. For intermediate- and high-risk localized cancers, radical prostatectomy (surgical removal) and definitive external beam radiation therapy combined with brachytherapy and hormone therapy deliver high long-term cancer control and cure rates, making them standard benchmark treatments evaluated on a case-by-case basis.