Hormone therapy before radiation seed implants for prostate cancer

May shorten life for older patients

Boston – Men over 70 years of age with early-stage prostate cancer have 20 percent higher mortality if they are treated first with hormone therapy before being treated with radiation seed implants (brachytherapy), compared to men who are treated with brachytherapy alone, according to the largest cohort study of its kind presented September 23, 2008, at the American Society for Therapeutic Radiology and Oncology's 50th Annual Meeting in Boston.

New research shows that hormone therapy can have negative effects on survival, in addition to many other previously known side affects from this treatment. This is important to consider when weighing treatment options, especially since hormone therapy (called neoadjuvant hormone therapy or NHT) is sometimes used to shrink the prostate before brachytherapy treatment of localized prostate cancer but does not improve the patient's chance of being cured. Localized prostate cancer means it has not spread outside of the prostate.

"Our study shows that for men over 70 with early-stage prostate cancer, androgen deprivation therapy as a form of treatment may do more harm than good," Amy Fox, M.D., lead author of the study and a radiation oncology resident at the Harvard Radiation Oncology Program in Boston, said. "In older patients, the risks of androgen deprivation need to be carefully weighed by doctors when designing the proper treatment plan."

Androgen deprivation therapy is hormone therapy used to treat prostate cancer by lowering the level of male hormones (androgens) to shrink the prostate or slow down the growth of prostate cancer. Brachytherapy is a procedure where a radiation oncologist places small radioactive seeds into the prostate to kill the cancer cells while the man is sedated.

"These results are particularly interesting, since two previous studies that examined similar populations contradicted each other in terms of how hormone therapy impacts the risk of death among prostate cancer patients in this age group," Dr. Fox said.

The cohort study involved 1,709 men at least 70 years of age with localized prostate cancer who were treated with either NHT and brachytherapy or with brachytherapy alone at centers within the 21st Century Oncology consortium between 1991 and 2005. Findings show that men in this age group with localized prostate cancer who were treated with both NHT and brachytherapy had a 20 percent increased risk of dying, compared to men who were not treated with NHT.

For more information on radiation therapy for prostate cancer, visit www.rtanswers.org.