Hormone therapy
may not work as effectively in all prostate
cancer patients, according to a newly released study.
Hormone
therapy, which works by blocking the output of testosterone that fuels prostate
tumors, is a key treatment for patients with an advanced form of the disease.
Earlier studies have shown it improves survival rates in men with aggressive
prostate cancer.
Amy Dosoretz, M.D., lead
author of the study and a resident in the Harvard Radiation Oncology Program
says, “There is no evidence showing hormones help patients with “low-risk” or
slow-growing tumors.”
The study
included 1,700 male patients over the age of 70 diagnosed with early stage
prostate cancer.
Researchers
found that patients’ who received hormone therapy prior to brachytherapy treatment,
increased their risk of death by 20 percent, compared directly to the other
patients who only received radiation therapy.
Brachytherapy
is a procedure where the doctor implants tiny permanent radioactive seeds into
the prostate where they irradiate the cancer from inside the gland.
After five
years, 19.1 percent of those patients given hormones died, compared to 16.6
percent of those who did not get hormones.
Hormone therapy
did not increase the risk of death in men who are younger than 70, says Dosoretz.
The men
received hormones for 3 to 3½ months. Patients were not randomly assigned to one
treatment over the other, rather, doctors observed how men given each treatment
fared.
Two previous
studies on this topic have shown conflicting results, Dosoretz says. One study
found hormonal treatment increased the risk of death, while the other did not.
Patients and
doctors need to weigh the benefits and risks of therapy carefully. Patients with early stage tumors, the elderly and those patients with
other health problems – such as heart disease – may be more harmed, rather than
helped by hormone therapy, said Grace
Lu-Yao, PhD, MPH, an associate professor at Robert Wood Johnson Medical School.
The study was
presented at the American Society for Therapeutic
Radiology and Oncology (ASTRO) annual meeting in Boston,
Massachusetts on September 21, 2008.
In another
recent study, experts advise against regular prostate
cancer screenings in men 75 and older, saying the risks far outweigh
the benefits for men in that age group, according to a new report published in
the Annals of
Internal Medicine. #