Radioactive particle implantation, also known as brachytherapy, is a less invasive and more effective curative treatment for prostate cancer. Simply put, it is similar to radical prostatectomy in that it is used for early stage prostate cancer and has the same efficacy as radical prostatectomy, but is less invasive, with faster recovery and fewer complications for the patient. The following criteria are recommended by the American Brachytherapy Society (ABS): (1) The following three criteria are met for brachytherapy alone: (1) clinical stage T1 to T2a; (2) Gleason classification 2 to 6; (3) PSA <10ng/ml. (2) Any one of the following conditions is an indication for brachytherapy combined with external radiotherapy: ① clinical stage T2b, T2c; ② Gleason grade 8-10; ③ PSA >20ng/ml; ④ peripheral nerve invasion; ⑤ positive pathological results of multi-point biopsy; positive pathological results of bilateral biopsy; ⑥ MRI examination clearly shows extra-prostatic envelope invasion. Most scholars recommend external radiotherapy followed by brachytherapy to reduce the complications of radiotherapy. (3) If the Gleason score is 7 or PSA is 10-20 ng/ml, the combination of external radiotherapy should be decided on a case-by-case basis. (4) Indications for brachytherapy (or combined external radiotherapy) combined with endocrine therapy: prostate volume > 60ml, neoadjuvant endocrine therapy can be performed to shrink the prostate.