The finding of a higher incidence of prostate cancer among men living in less deprived areas is also consistent with previous research.13, 14 In the absence of known modifiable risk factors, this may reflect higher rates of prostate-specific antigen testing among less deprived men and hence higher rates of overdiagnosis.28, 29, 30 The decline in incidence among the least deprived in the most recent study period is as yet unexplained but may reflect changes in clinical practice. This evidence concerns the gene KLK3 and prostate cancer.