Permanent interstitial low-dose-rate brachytherapy for patients with localised prostate cancer: a systematic review of randomised and nonrandomised controlled clinical trials

Abstract

Context: Prostate cancer (PCa) is the most common cancer in men. Permanent interstitial low-dose-rate brachytherapy (LDR-BT) is a short-distance radiation therapy in which low-energy radioactive sources are implanted permanently into the prostate.

Objective: To assess the effectiveness and safety of LDR-BT compared to treatment alternatives in men with localised PCa.

Evidence acquisition: Bibliographic databases (Medline, Embase, and the Cochrane Library) were searched from inception until June 2010 for randomised and nonrandomised controlled trials comparing LDR-BT with radical prostatectomy (RP), external-beam radiation therapy (EBRT), or no primary therapy (NPT). Primary outcome was overall survival (OS). Secondary outcomes were disease-free survival (DFS), biochemical recurrence-free survival (bRFS), physician-reported severe adverse events (SAE), and patient-reported outcomes (PRO).

Evidence synthesis: A total of 31 studies, including 1 randomised controlled trial (RCT), were identified. Risk of bias was high for all 31 studies. OS was reported in one nonrandomised controlled study; however, these data were not interpretable because of strong residual confounding. DFS was not reported. Comparison of bRFS between treatment groups is not validated; thus, results were not interpretable. Physician-reported urogenital late toxicity grade 2 to 3 was more common in the LDR-BT group when compared to the EBRT group. With respect to PRO, better scores for sexual and urinary function as well as urinary incontinence were reported for LDR-BT compared to RP. Better scores for bowel function were reported for LDR-BT compared to EBRT.

Conclusions: We found a low amount of evidence in studies that exclusively compared LDR-BT with other treatment modalities. LDR-BT may have some different physician-reported SAE and patient-reported outcomes. The current evidence is insufficient to allow a definitive conclusion about OS. Randomised trials focusing on long-term survival are needed to clarify the relevance of LDR-BT in patients with localised PCa.