Once-weekly therapy improves bone density in prostate cancer patients

Among men with nonmetastatic prostate cancer receiving androgen deprivation therapy, once-weekly alendronate (Fosamax) improves bone density and decreases turnover, according to data published in the Journal of Clinical Oncology (2008; 26:4426-34).

A second year of alendronate provides additional skeletal benefit, whereas discontinuation results in bone loss and increased bone turnover, researchers say. Delay in bisphosphonate therapy appears detrimental to bone health.

In the study, first author Susan L. Greenspan, MD, of the University of Pittsburgh, and colleagues, analyzed 112 men with nonmetastatic prostate cancer. The patients were randomly assigned to alendronate, 70 mg once weekly, or placebo in a double-blind, partial-crossover trial with a second random assignment at year 2 for those who initially received active therapy. Outcomes included bone mineral density and bone turnover markers.

Men initially randomly assigned to alendronate and randomly reassigned at year 2 to continue had additional bone density gains at the spine (mean, 2.3%) and hip (mean, 1.3%; both p<.01); those randomly assigned to placebo in year 2 maintained density at the spine and hip but lost (mean, –1.9%; p<.01) at the forearm. Patients randomly assigned to begin alendronate in year 2 experienced improvements in bone mass at the spine and hip but experienced less of an increase compared with those who initiated alendronate at baseline.

Men receiving alendronate for 2 years experienced a mean 6.7% increase at the spine and a 3.2% at the hip (both p<.05). Bone turnover remained suppressed, the authors said.