How Long Do Lupron Injections Work?

Dear Dr. Motola,

If you have had prostate surgery and need salvage radiation, but elect to take injections instead, how long will the lupron injections work?

Lupron is a drug that inhibits the production of gonadotropins (LH and FSH), resulting in the reduction of testosterone to castration levels. It is mainly intended for the treatment of metastatic prostate cancer however other uses in the management of this disease are also utilized widely. This decrease in testosterone helps control the prostate cancer, however when treated with Lupron this only causes prostate cancer cells to stop growing or possibly grow at a slower rate.

Prostate cancer that has spread beyond the prostate is not curable.  I am not certain whether you are undergoing radiation immediately after surgery for positive margins, or if this represents salvage that is being done years after the original operation.

Unfortunately, Lupron does not work forever as the cancer cells will change so that they grow even though the testosterone levels have fallen (hormonally resistant prostate cancer). Many studies show that nearly half of the patients stop responding to hormone treatment within 3 years.