Researchers Devise New Ways to Treat Prostate Problems
By LAWRENCE K. ALTMAN
Published: December 26, 1989
QUESTIONS about the long-term safety and effectiveness of the standard operation for enlarged prostates have led to intensified efforts to develop new ways to treat the condition, which is common among older men. Among the alternatives are several new drugs, hormones, mechanical devices, new kinds of surgery and even intense heat.
The prostate, a walnut-sized gland in the pelvis, produces fluid that helps to nourish and transport sperm. The prostate surrounds the urethra, the tube that carries urine from the bladder through the penis.
For unknown reasons, as men age non-cancerous tumors frequently enlarge the prostate and can block the flow of urine through the urethra. This produces more frequent urination and other symptoms. The condition is known as benign prostatic hypertrophy.
Because a severe blockage can occur suddenly and damage the kidneys and other parts of the urinary system, many doctors recommend early surgery. The procedure that is standard now is called a trans-urethral resection of the prostate. In the procedure, a device is passed through the urethra to shave the areas of the prostate blocking the flow of urine.
But the operation can leave patients impotent and often must be repeated. New studies also suggest that the death rate for seemingly unrelated conditions, like heart attacks, increases years after surgery.
At dozens of medical centers across the country, hundreds of urologists are exploring the potential benefits of several experimental treatments as alternatives. One promising treatment is a balloon device that squeezes prostates from within the urethra to enlarge the passage.
Several hundred people are participating in a trial of a new drug that may shrink prostates without affecting sexual function, a side effect associated with some earlier drugs. A variety of other medications are being evaluated in other studies.
The aim of another experimental technique, hyperthermia, is to use high temperatures to shrink the key internal areas of the gland that block the flow of urine.
For some patients, surgeons are testing a simpler operation in which they make a deep cut into the prostate instead of removing portions of the gland. Although doctors are uncertain how the surgery works, the simpler operation does reduce the size of the prostate.
''There is a great deal of zeal for alternatives,'' said Dr. Joseph B. Dowd of the Lahey Clinic in Burlington, Mass., who is one of those trying to develop a new therapy.
Leading urologists estimate that 350,000 of the standard operations will be performed this year at a cost of up to $500 million, including hospital care. Such operations are second only to cataract extractions as the most common operation paid for by the Federal Medicare program.
Urology experts say that benign prostatic hypertrophy affects about 8 percent of men in their 30's, but that increases to 70 percent of men at age 70; by age 80, about one in four men have prostate surgery. Many experts expect the number of prostate operations and their costs to rise as more Americans live longer.
For decades, the standard operation and its predecessor, the open prostatectomy in which the gland is removed through an incision in the abdomen, have been virtually the only therapies of proven value for enlarged prostates. Open prostatectomy is now usually reserved for glands that are too large for the standard procedure.
The standard procedure itself carries some risks: doctors have long known that impotence can result. That can happen in as many as 10 percent of the cases, by some estimates, although the precise frequency is not known.
More recently, urologists have been surprised by findings of researchers at Dartmouth Medical School in Hanover, N.H. A study there analyzing the outcome of prostate surgery in selected areas of Denmark, England and Canada found that the standard operation led to an increased risk of death from heart attacks after the operation.
But many experts say the study was flawed and standard surgical treatments remain the first choice.
Dr. H. Logan Holtgrewe of Annapolis, Md., who is an officer of the American Urological Association, said the association is studying the effectiveness of the standard operation and the frequency of complications. But he said the operation is the standard for the treatment of enlarged prostates. Mysteries of the Condition
The mysteries of the condition complicate the problem of developing therapies. Urologists have long been perplexed about the absence of a correlation between the size of the gland and the resulting symptoms. Many men with large prostates have no symptoms, while many with smaller glands have severe symptoms.
Moreover, the severity of symptoms often fluctuates unpredictably. In earlier studies as many as 30 percent of men have reported improvement after taking what they did not know was a placebo, or dummy treatment.
Little basic research has been done on the condition, and much of what was done has been flawed or failed to follow many patients for more than a year, said Dr. Herbert Lepor of the Medical College of Wisconsin in Milwaukee.