The effect of prostate cancer screening on stage IV disease in America.

OBJECTIVE: Some studies have found that prostate cancer (PCa) screening provides little or no change in PCa-related mortality during the 7-10 years following diagnoses. However, most men are diagnosed with PCa at low-stage disease and die of unrelated causes during this period. Men diagnosed at stage IV are at much higher risk of dying of the disease. Therefore, stage IV rates at first diagnoses may be a surrogate marker of PCa-related mortality over a time span less than 10 years. The study objective is to examine the association between PCa screening and stage IV disease rates in new cases to explore potential benefits for PCa screening.
MATERIALS AND METHODS: The percent of stages I, II, III, IV and unclassified PCa diagnosed in white males in 2005 was compared to PCa screening rates on a state-by-state basis. To consider access to medical care and socioeconomic status, median family income, degree of urbanization, urologist population density and health insurance status were included in the analysis.
RESULTS: PCa stage IV disease correlated inversely with PCa screening rates (r = -0.42, P = 0.006) where r is the correlation coefficient and P is the probability. Stage I PCa correlated with lack of health insurance (r = 0.37, P = 0.02).
CONCLUSIONS: The results of this study suggest that with PCa screening may be associated with reduced rates of stage IV disease.