Surgery for early prostate cancer increases survival by 38% in younger men compared to watchful waiting, a Swedish study finds, but the results may not be applicable in the United States because the patients were diagnosed much later than typical U.S. patients.
Dr. Anna Bill-Axelson of University Hospital in Uppsala, Sweden, and her colleagues studied 695 men diagnosed with early prostate cancer. Half were assigned to receive surgery to remove the cancerous prostate gland and half were assigned to what is known as watchful waiting or aggressive monitoring, in which no medical action is taken until the tumor shows signs of growing or spreading. In 2002, they reported the results from three-year follow-up of the patients and concluded that early surgery was better. In a new report published this week in the New England Journal of Medicine, they reported results from 15 years of follow-up and reached the same conclusion.
Among men under the age of 65 at the beginning of the study, 14.6% who underwent surgery had died after an average follow-up of 13 years, compared to 20.7% of those consigned to watchful waiting, a 38% decrease in mortality. For men over the age of 65, however, surgery was much less beneficial. Overall, 15 patients had to undergo surgery to prevent one death, but for men under 65, only seven had to undergo surgery to prevent one death. More men in the watchful waiting group died of causes other than prostate cancer, the researchers said, but most were found to have spreading prostate cancer that likely would have proved fatal.
But the fly in the ointment is that most of the men in the study were diagnosed after symptoms had appeared. Fully 88% of the men had tumors that could be felt on a digital rectal exam. In the United States today, however, prostate cancers are generally diagnosed by a PSA test and fewer than half have a tumor that is detectable on a digital rectal exam. That means that prostate cancers are now diagnosed about seven to 10 years earlier here than they were in the Swedish study, and there is little or no evidence to indicate whether surgery is appropriate for tumors that are diagnosed so early, said Dr. Matthew R. Smith of Massachusetts General Hospital, who wrote an editorial that accompanied the report.
A priori, it might seem like surgery would be a good solution, even for early prostate cancers. The problem is that surgery is associated with side effects that have a severe effect on quality of life, particularly impotence and urinary incontinence. Nerve-sparing surgery has reduced the incidence of such problems, but not eliminated it. Other treatments also present potential problems. Radiation therapy is associated with impotence and an increased risk of secondary cancers, while chemotherapy produces nausea, breast enlargement, weakness, hair loss and fluid retention. Many men would thus prefer to take their chances on a wait-and-see approach rather than risk those problems.
Unfortunately, because of the criteria used for patient selection, this new study will probably do little to help them make that decision.