P68. Which IV bisphosphonates must be used after initiating androgen deprivation therapy in patients submitted to radical prostatectomy experiencing recurrence? A prospective open-label controlled study

Abstract

Objectives: Androgen-deprivation therapy (ADT) may promote osteoporosis and osteopenia. Methods: 94 prostatectomized men with rising PSA were enrolled into the placebo group (31), monthly IV clodronate (39) or monthly IV zoledronic acid (24) for 36 months. Dualenergy x-ray absorptiometry measured the bone density in the lumbar (L2–L4) area. Chi-squared and ANOVA tests were used. Results: After 6 months of androgen deprivation 17 out of 31 cases of control cases developed osteopenia in the lumbar area. In 12months, 9 control cases reached osteoporosis with 13 additional cases of osteopenia. At the end of the 36months study period the untreated group showed an average BMD loss of 1.82 (±0.94) with 13 cases of osteopenia and 18 cases of osteoporosis. Clodronate group showed 2 cases of osteoporosis out of 39 after 6 months on androgen deprivation with 28 developing osteopenia and 7 cases of osteoporosis after 36 months of follow-up. Mean BMD loss in this group was 0.72 (±0.34). Zoledronic acid studied arm showed 7 cases of osteopenia after 6 months on androgen deprivation while 20 and 5 cases developed osteopenia and osteoporosis respectively after 36 months of follow-up. The former group had mean bone loss of 0.88 (±0.32). There was statistical difference for BMD loss in the treated groups starting at 6 months in comparison to the control group. Conclusions: There is impressive bone loss after androgen deprivation but it can be reverted by preventive bisphosphonates usage.