Hormone therapy fails to prevent prostate cancer spread

Androgen deprivation therapy, also known as hormone therapy, is the gold standard of care for men whose prostate cancer is advanced and has spread throughout the body. The therapy works by shutting down male hormones, principally testosterone, that can promote prostate cancer growth.

The Oregon Health & Science University Cancer Institute study was initiated because little is currently known about the effectiveness of hormonal therapy in men whose cancer remains localized within the prostate.

In the retrospective study, the research team examined demographic data, socio-economic factors and tumor biology in relationship to overall survival and cancer-specific survival for a subgroup of 276 subjects from the Prostate Cancer Outcome Study (PCOS) who had localized prostate cancer and received androgen deprivation therapy as their primary treatment. Between 1994 and 1995, a total of 3,486 men were enrolled in PCOS within six months of prostate cancer diagnosis.

The analysis showed that, out of all the demographic and socio-economic factors considered, overall survival was predicted only by age and certain features of prostate cancer. Tumor biology, which is measured by Gleason score, was the only independent predictor of cancer-specific survival. Tumor mass as measured by prostate specific antigen (PSA) approached statistical significance as a predictor. Nearly 10% of men died from prostate cancer within five years of starting hormonal therapy.

“The notion that androgen deprivation therapy will hold prostate cancer at bay while you die of something else is not proving to be entirely true,” said Dr Tomasz Beer, director of the prostate cancer research program at the Oregon Health & Science University Cancer Institute.

“Studies suggest that more needs to be known about the risks and benefits of this treatment before we recommend it to patients with localized disease,” he continued.