Early Detection of Metastatic Prostate Cancer: Impact on Incidence and Survival
Posted: Tuesday, September 4, 2018
In a retrospective analysis of two national registries of patients with prostate cancer, published in the journal Cancer, John T. Helgstrand, MD, PhD, of the Copenhagen Prostate Cancer Center, Copenhagen University Hospital, and colleagues found that earlier detection strategies decrease the incidence of de novo metastatic prostate cancer. However, disease-specific mortality rates are still high and the “unsolved issue of overdetection and overtreatment” of indolent prostate cancer remains.
“More exact knowledge could strengthen the conclusions regarding the impact of [prostate-specific antigen]–based early detection strategies,” the researchers clarified.
Men diagnosed with prostate cancer identified in the U.S. Surveillance, Epidemiology, and End Results (SEER) program (1980–2011) and the Danish Prostate Cancer Registry (DaPCaR; 1995–2011) were compared. Historically, Denmark has differed from the United States in that it has never recommended prostate-specific antigen (PSA)-based early detection of prostate cancer. A total of 426,266 men from the SEER cohort and 47,024 men from the DaPCaR cohort were analyzed for incidence and 5-year mortality rates.
In the SEER cohort, the incidence of de novo metastatic prostate cancer decreased from 12.0 to 4.4 per 100,000 men, whereas that in the DaPCaR cohort increased from 6.7 to 9.9 per 100,00 men. The 5-year mortality analyses yielded conflicting results, as they remained mostly consistent in the SEER cohort but decreased in the DaPCaR cohort.
The investigators attributed the decreased mortality in the Danish cohort to lead time, caused by increased frequency of PSA testing over time. Although early detection strategies appear to decrease the incidence of de novo metastatic prostate cancer, this must be considered with factors such as overdiagnosis, overtreatment, and high mortality rates.
