Interstitial brachytherapy for prostate cancer--just an expensive variant of 'watchful waiting'?

As a result of the recent resurgence of interest in interstitial brachytherapy, extended follow-up studies of early experience in this field are now being reported. However, such outcomes must be evaluated within the context of recent comprehensive assessments of the age-specific natural history of conservatively managed prostate cancer ('watchful waiting', i.e. no curative intervention). This raises issue with the contention that treating patients with low-grade cancer using brachytherapy alone results in a treatment-derived, extended, clinical-progression-free survival. The necessity for proposed randomized trials of brachytherapy (compared with conservative management in low-grade disease, and brachytherapy plus external beam radiotherapy) is discussed in this context. There is no consensus regarding the best modality for the treatment of localized prostate cancer, since no well-accepted, adequately powered randomized trial of competing modalities for this disease has ever been completed. Consequently, it has become common while counseling patients with the disease to place substantial emphasis on 'quality of life' considerations and the 'outcomes uncertainty management' issues associated with each option of therapy. There is even a question of whether every patient who is diagnosed with prostate cancer should be treated. However, while the importance of the variable biologic risk is generally widely accepted by experienced physicians caring for such patients, it is extremely difficult for the individual patient to weigh the evidence of the relative risks of progression dispassionately at the time of diagnosis. In this review, I wish to highlight several papers that have been published within the past year that are important in addressing this ongoing clinical problem. Any physician counseling patients about localized prostate cancer treatment should read and become familiar with the data herein: papers addressing the issues of interstitial brachytherapy outcomes, and the natural history of prostate cancer itself.