Screening for cervical, prostate and breast cancer: interpreting the evidence

Abstract

Cancer screening is well-established in high income countries, but its evidence base is constantly evolving and often contentious. This leaves physicians and policymakers in a difficult position, forced to act in the context of methodological complexity and substantive disagreement.1,2 Three cases of screening for cancer or cancer risk are considered: cervical, prostate and breast screening. The unique characteristics of the disease, test and program in each case are outlined in Table 1. Tables 2-4, catalogue sources of controversy in each case; these are discussed in more depth below. The concluding section presents five common themes that may help explain the ongoing controversies. The aim is not to synthesize the evidence, but to provide the ‘backroom’ story of the evidence on cancer screening, and so illuminate why experts so often disagree.