Stage IIB Prostate Cancer American Joint Committee on Cancer (AJCC) v8

This phase II trial investigates the effect of high dose-rate brachytherapy and stereotactic body radiotherapy in treating patients with prostate adenocarcinoma. Brachytherapy, also known as internal radiation therapy, uses radioactive material placed directly into or near a tumor to kill tumor cells. Stereotactic body radiation therapy uses special equipment to position a patient and deliver radiation to tumors with high precision. This method may kill tumor cells with fewer doses over a shorter period and cause less damage to normal tissue.