Prostate cancer mortality rates see greater decline in U.S. compared with U.K.

Prostate cancer mortality rates in the United States have declined at a much greater rate than in the United Kingdom, coinciding with a higher uptake of prostate-specific antigen screening in the United States, according to new research.

The researchers from the United States and the United Kingdom analyzed trends in prostate cancer-associated mortality and incidence in both countries from 1975 to 2004 and compared their observations with trends in screening and treatment.

Using joinpoint regression analysis of mortality statistics from both the U.K. National Cancer Research Network and the NCI’s Surveillance Epidemiology and End Results program, the researchers estimated changes in the annual percentage of prostate cancer mortality, as well as the points when the trends changed.

Overall, age-specific and age-adjusted prostate cancer mortality peaked during the early 1990s, with nearly identical rates in both countries. However, age-adjusted mortality in the United States declined by –4.17% (95% CI, –4.34 to –3.99) each year after 1994. This rate was four times the rate of decline seen in the United Kingdom after 1992 (–1.14%; 95% CI, –1.44 to –0.84).

According to the researchers, the greatest and most sustained decline in mortality occurred among American patients aged 75 years and older (–5.32%; 95% CI, –8.23 to –2.32). In the United Kingdom, however, mortality rates in this age group reached a plateau by 2000.

Explanations for the differences in mortality trends included the possibility of an early effect of initial rounds of screening on men with more aggressive asymptomatic disease in the United States and different approaches to treatment found in both countries.

Lancet Oncol. 2008;doi:10.1016/S1470-2045(08)70104-9.