Transperineal image-guided permanent brachytherapy for localized cancer of the prostate

Traditionally, organ-confined adenocarcinoma of the prostate has been treated with radical prostatectomy or external beam radiotherapy (EBRT). Permanent implantation of iodine-125 (I-125) seeds into the prostate via a free-hand, retropubic approach was introduced in 1970. However, its popularity was short-lived because suboptimal results were obtained due to the inadequate and inhomogeneous distribution of seeds within the prostate gland. Over the last decade, there has been a resurgence in prostate brachytherapy due to the introduction of a transperineal approach, transrectal ultrasound imaging, fluoroscopy, three-dimensional visualization, and computerized treatment planning. Thus, the radioactive seeds can be placed more accurately and homogeneously within the prostate gland. Selection criteria for brachytherapy is based on the pretreatment prostate specific antigen level, clinical stage at presentation, and Gleason grade. Patients with high likelihood of organ-confined disease are treated with brachytherapy only, whereas those with more advanced disease are treated with brachytherapy in conjunction with EBRT and/or hormonal manipulation. I-125 (145 Gy) or palladium-103 (120 Gy) are the common radioisotopes used. Ten-year actuarial biochemical progression-free rates of 64 to 93% (which are comparable to those obtained by surgery or EBRT), with minimum associated morbidity, have been reported from centers routinely performing transperineal permanent prostate brachytherapy. Brachytherapy is a good treatment option for localized prostate cancer and the results very much depend on the expertise, skill, and experience of the brachytherapy team. Randomized clinical trials are required to firmly establish the role of brachytherapy in the management of localized prostate cancer.