Prostate Study: Post-Treatment Impotence Widespread
Tuesday, October 29, 2002
Few aspects of prostate cancer treatment arouse as much confusion -- or controversy -- as the rates of sexual dysfunction after various therapies.
The results of a large federally funded study published this month in the journal Cancer are certain to fuel the debate about the sexual side effects of surgery and radiation. The study of more than 1,200 men treated at the Cleveland Clinic between 1992 and 1999 paints a bleak portrait, concluding that "the great majority of men . . . do not achieve a return to functional sexual activity."
Previous studies, many of which have focused on the aftermath of surgery, have found that 20 to 80 percent of men are left impotent. This wide variation is due to multiple factors, experts say: the man's age, potency before diagnosis, the treatment employed, the skill of the treating physician and the size and location of the cancer. An estimated 30 to 50 percent of men diagnosed with prostate cancer already are impotent at the time they are diagnosed.
For years urologists and radiation oncologists have sparred over whether impotence is more common after surgery than after radiation delivered either by conventional methods or through a newer treatment known as brachytherapy, in which radioactive "seeds" are implanted in the prostate. A meta-analysis published several years ago found that radiation had fewer sexual side effects than surgery. But the authors of the new study, one of the largest to date, say their findings refute that conclusion.
Among the best results reported so far are those from Johns Hopkins Hospital of men who underwent bilateral nerve-sparing surgery, a procedure designed to preserve sexual function that was pioneered by Hopkins's chief urologic surgeon, Patrick C. Walsh. Two years ago Walsh and his colleagues published a study reporting that 86 percent of 64 men were able to achieve erections 18 months after this surgery. One-third of these men, whose average age was 57, used Viagra.
Privately, specialists at other hospitals have questioned those numbers, which are higher than most reported by other surgeons who are performing the same operation. Some urologists say Hopkins's rates are atypical because its patients are younger and healthier than most prostate cancer patients.
In the latest study, lead author Leslie R. Schover, a psychologist at Houston's M.D. Anderson Cancer Center, and doctors at the Cleveland Clinic analyzed demographic characteristics of patients and treatments to determine which factors were related to better sexual outcomes.
Schover's team found that age was strongly associated with a return to potency: The younger the man, the better the outcome. The average age of men in the study was nearly 69, older than men in previous studies of the sexual side effects of prostate cancer.
Men who underwent nerve-sparing prostatectomy or brachytherapy fared better sexually than those who opted for conventional external beam radiation or hormonal treatments, the researchers found. Patients who took hormones fared poorest, possibly because the drugs suppress testosterone, the male sex hormone.
The researchers found that the men who underwent surgery, especially those who had nerve-sparing prostatectomy, reported more success using Viagra than the brachytherapy group.
And men who chose treatment based in part on its effect on sexual function fared better than those who did not consider potency to be important.
-- Sandra G. Boodman