Evaluation of Bone Turnover / Quality Markers and Bone Mineral Density in Prostate Cancer Patients Receiving Androgen Deprivation Therapy with or without Denosumab

Background/Aim: Androgen deprivation therapy (ADT) is a mainstay therapy for prostate cancer (PCa). ADT induces bone loss and increases the risk of osteoporosis and fractures. Recently, loss of bone quality has received attention as a factor that causes loss of bone strength independent of bone mineral density (BMD). Pentosidine has been identified as a surrogate marker of bone quality. Therefore, bone quality markers were evaluated retrospectively in PCa patients receiving ADT with or without denosumab. Patients and Methods: This study included 46 PCa patients. Twenty patients received denosumab. We measured pentosidine as bone quality marker and TRACP-5b as bone turnover marker. Pre- and 12month BMD was measured in the lumbar spine and femoral neck. Results: In the denosumab group (D+), BMD at the lumbar spine was increased by 6.7% compared with the group that did not receive denosumab (D-) at 12 months (p=0.0015). BMD at the femoral neck was increased by 3.1% at 12 months (p=0.0076). The mean value of TRAP-5b was lower in the D+ group than the D-group at 12 months (p<0.001). The mean serum levels of pentosidine in the D+ group were decreased by -39.6% compared with the D-group at 12 months (p=0.0036). Conclusion: Denosumab increased BMD during ADT for PCa and inhibited the increasing levels of serum pentosidine in PCa patients undergoing ADT.