Toronto—About one-half of patients with prostate cancer receive androgen deprivation therapy (ADT) at some point during their treatment. Among the adverse effects, however, are significant bone loss and increased risk of fractures.

In response to calls for a more systematic approach to bone health in these patients, a study published in the Annals of Internal Medicine looked at ways to mitigate the issues.  University of Toronto researchers and colleagues found that both bisphosphonates and denosumab improve bone mineral density (BMD) in men with nonmetastatic prostate cancer who are receiving ADT.

To reach that conclusion, a multidisciplinary panel reviewed 30 studies evaluating the effectiveness of bone-targeted therapies aimed at preventing fracture and improving BMD in men with nonmetastatic prostate cancer receiving ADT. Two systematic reviews and 28 reports of 27 trials met inclusion criteria, all of them focusing on men with nonmetastatic prostate cancer who were initiating or continuing ADT.

The review indicates that bisphosphonates were effective in increasing BMD, but no trial was sufficiently powered to detect reduction in fractures. Based on one trial deemed high-quality, denosumab appeared to improve BMD and reduce the incidence of new radiographic vertebral fractures.

The study authors note that no trials compared calcium or vitamin D versus placebo and that three lifestyle-intervention trials did not show a statistically significant difference in change in BMD between exercise and usual care.

“Both bisphosphonates and denosumab improve BMD in men with non-metastatic prostate cancer who are receiving ADT,” the researchers conclude. “Denosumab also reduces risk for radiographic vertebral fractures, based on 1 trial. More trials studying fracture outcomes are needed in this population.”

An accompanying editorial from commentators at Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, both in New York, notes that the review includes studies of men without metastatic prostate cancer receiving ADT. “For these patients, bone loss and fracture risk increase over time as a result of depletion of testosterone and estradiol from ADT,” the commentators write. “Sarcopenia further increases fracture risk in the setting of low bone mineral density (BMD) and high risk for falls.”

« Click here to return to Weekly News Update.