DALLASAn analysis of SEER data shows small but steady decreases in prostate cancer mortality since 1991, Robert A. Stephenson, MD, said at the American Urological Association annual meeting. He attributed the decline to a combination of factors, including earlier detection and better treatment of advanced disease. Yet overall, he said, the data show that prostate cancer remains a major cause of death in men and may be undertreated in the elderly.
37% Die of Their Cancer
The study, by Dr. Stephenson, professor of urological oncology at the University of Utah, and his colleague Dr. Charles R. Smart, showed that 37% of men diagnosed with prostate cancer eventually die of their prostate cancer. He noted that of those men destined to die of prostate cancer, 61% had done so by 5 years after diagnosis, and 88% by 10 years.
Almost three-fourths (71%) of men who died of prostate cancer did so at ages 65 to 84, with more men dying at age 75 to 79 than in any other 5-year age category (see Figure). These data demonstrate the substantial burden carried by men dying of prostate cancer, Dr. Stephenson said.
Overall 10-year prostate cancer relative survival rates have increased by 20% from 1988 to 1995. He noted, however, that men diagnosed of prostate cancer at age 80 years and older have 20% lower relative survival rates than younger men, indicating substantial relative risk of death from prostate cancer and suggesting possible undertreatment of these elderly men.
The study analyzed 123,112 deaths of men diagnosed with prostate cancer, of which 44,978 were attributed to their prostate cancer. This represents all deaths in men with prostate cancer obtained from the defined geographic regions of the SEER (Surveillance, Epidemiology and End Results) program for 1973 to 1995.
The researchers determined age-adjusted mortality rates, relative survival rates (ratio of observed survival of prostate cancer cases to expected survival for the general population), and crude deaths per year and by age category, as well as relative survival rates by treatment.
The study showed that age-adjusted US mortality rates for prostate cancer peaked in 1991 and had declined by 11% through 1996. Among white men, mortality peaked in 1991 at 24.67 deaths per 100,000 and declined to 21.99 in 1996, a drop of 11%. For African-American men, mortality peaked in 1993 at 56.22 deaths per 100,000 and declined to 53.68 in 1996, a drop of nearly 5%.
An analysis of survival by treatment showed that patients who received radical prostatectomy had a 10-year relative survival rate of 111%, compared with 82% and 42% for those undergoing radiation therapy and conservative management, respectively.