Bisphosphonate therapy in patients under androgen deprivation therapy for prostate cancer: A systematic review and meta-analysis

The objective of this study was to clarify the role of bisphosphonates in the treatment of osteoporosis in patients with prostate adenocarcinoma under androgen deprivation therapy (ADT). The Medline, EMBASE, Cancerlit and the American Society of Clinical Oncology abstract databases were searched for published randomized, placebo-controlled trials evaluating the usage of bisphosphonates in patients with prostate cancer (PC) under ADT. The outcomes assessed were fracture, osteoporosis, incidence of adverse events and changes in bone mineral density (BMD) during treatment. A total of 15 articles (2634 participants) were included in the meta-analysis. Treatment with bisphosphonates showed a substantial effect in preventing fractures (risk ratio (RR), 0.80; P=0.005) and osteoporosis (RR, 0.39; P < 0.00001). Zoledronic acid showed the best number needed to treat (NTT), compared with placebo, in relation to fractures and osteoporosis (NNT=14.9 and NNT=2.68, respectively). The between-group difference (bisphosphonates vs placebo) in the lumbar spine and femoral neck BMD were 5.18±3.38% and 2.35±1.16%, respectively. This benefit of bone loss prevention could be reached without major side effects (cardiovascular or gastrointestinal events). Bisphosphonates are effective in preventing bone loss in patients with PC who are under ADT.