"Most oncologists recommend that men with high-risk prostate cancer be given two or more years of hormone therapy after they undergo radiation treatment or surgery," says researcher Cliff Robinson, MD, a radiation oncologist at The Cleveland Clinic in Cleveland, Ohio.
"But we found that shorter-term hormone treatment is just as effective," he tells WebMD. "And the men presumably have a better quality of life, due to fewer side effects."
The study was presented here at the American Society for Therapeutic Radiology and Oncology's (ASTRO) annual meeting.
Impotence, Hot Flashes
Hormone therapy, also known as androgen-deprivation therapy, lowers the level of male hormones in the body, curbing the growth of prostate tumors.
Studies have suggested it can add years to men's lives. But there are side effects -- chiefly, reduced sexual desire, impotence, hot flashes, weakening of the bones, and breast growth or tenderness.
To see if the men could benefit from a shorter course of treatment, Robinson and colleagues reviewed the records of 579 patients with fast-growing prostate tumors who underwent surgery or radiation treatment at The Cleveland Clinic between 1996 and 2003.
The men were divided into three groups: one that did not take androgen-deprivation therapy, one that received six months or less of androgen deprivation therapy, and one that received more than six months of treatment. The men in the latter group took hormone therapy for an average of 15 months, Robinson says.
The results: 92% of the men who took either no hormone therapy or only six months of hormone treatment were alive five years later. Meanwhile, only 76% of those who took the drugs longer than six months survived five years.
Despite the findings, Theodore S. Lawrence, MD, PhD, head of radiation oncology at the University of Michigan Medical School in Ann Arbor, says he would be reluctant to offer men with high-risk prostate cancer that was likely to spread anything less than two years of hormone therapy.
"We have to be careful about interpreting the results, as this was not a randomized trial in which patients were randomly assigned to different treatment groups," Lawrence, the immediate past chairman of ASTRO's board of directors, tells WebMD. "It could be that the men who received more than two years of treatment were sicker to begin with."
Lawrence notes that another study presented at the meeting -- in which men were randomly assigned to receive either four months or 28 months of hormone therapy -- showed longer-course treatment decreased the chance of cancer spread.
But again, the longer treatment did not seem to save lives.
Robinson says further study is needed. "In the meantime," he says, "you should talk to your doctor about whether you need longer-term hormone therapy or whether a shorter course could be just as effective."
SOURCES: American Society for Therapeutic Radiology and Oncology's annual meeting, Philadelphia, Nov. 5-9, 2006. Cliff Robinson, MD, radiation oncologist, The Cleveland Clinic, Cleveland, Ohio. Theodore S. Lawrence, MD, PhD, head of radiation oncology, University of Michigan Medical School, Ann Arbor.
By Charlene Laino
Reviewed by Louise Chang