Mortality of patients with clinically localized prostate cancer treated with observation for 10 years or longer: A population based registry study

Purpose: We studied the outcome in patients with early and probably organ confined prostate cancer who were considered candidates for curative therapy and treated expectantly. Materials and Methods: The study included 2,570 patients with newly diagnosed prostate cancer reported to the Danish Cancer Registry from 1943 to 1986 and surviving for 10 years or longer. Mortality and causes of death were analyzed and stratified by stage, age and time of diagnosis. Excess mortality was calculated from life expectancy tables for the general population. Results: An overall excess mortality (standard mortality ratio 1.58, 95% confidence interval [95% CI] 1.51 to 1.65) was found. Young age and advanced clinical stage at diagnosis entailed a higher risk of death from prostate cancer. Overall. 42.7 and 19.1% of the patients who died had prostate cancer as the direct or contributing cause of death, respectively. Of the annual deaths 13% were attributable to prostate cancer. In 1,326 patients 55 to 64 and 65 to 74 years old with clinically localized prostate cancer at diagnosis the excess mortality was still significant (standard mortality ratio 1.72, 95% CI 1.54 to 1.93 and 1.50, 95% CI 1.39 to 1.62, respectively). Prostate cancer was the primary or contributing cause of death in 42.9% of the younger group and 21.5% of the older group. In these patients 15% of the annual deaths were related to prostate cancer. Conclusions: Patients with clinically localized prostate cancer for 10 years or longer, who were likely candidates for curative therapy when diagnosed, had significant excess mortality when treated expectantly.