The effect is the same as orchiectomy. Testosterone production by the testicles is stopped. The injections have no direct effect on the cancer, only an effect on the testicles. The lack of male hormone circulating in the blood kills the prostate cancer cells. The major advantage is no need for surgical removal of the testicles.
Most patients prefer the injections instead of having their testicles removed.
The disadvantages are the need for an injection every 1 to 4 months, but most men are willing to exchange the effort to spare their testicles. Allergic reactions have been reported and can result in a rare case of arthritis. Intermittent Hormone Therapy is currently being investigated. Intermittent hormone therapy is a treatment regimen where hormone therapy is started and when the cancer shrinks to a certain level as measured by the PSA , we stop the hormone therapy. The advantage of intermittent hormone therapy is a reduction in the side effects of the hormone therapy during the periods that the patient is off treatment and reduced overall costs.