Breast, prostate, and thyroid cancer screening tests and overdiagnosis

Abstract

The purpose of this study was to examine overdiagnosis and overtreatment related to cancer screening and to review relevant reports and studies. A comprehensive search of peer-reviewed and gray literature was conducted for relevant studies published between January 2000 and December 2015 reporting breast, prostate, and thyroid cancer screening tests and overdiagnosis. This study revealed no dichotomy on where screening would lower risk or cause overdiagnosis and overtreatment. Many screening tests did both, that is, at population level, there were both benefit (decreased disease-specific mortality) and harm (overdiagnosis and overtreatment). Therefore, we need to consider a balanced argument with citations for the potential benefits of screening along with the harms associated with screening. Although the benefits and harms can only be tested through randomized trials, important data from cohort studies, diagnostic accuracy studies, and modeling work can help define the extent of benefits and harms in the population. The health care cycle that prompt patients to undergo periodic screening tests is self-reinforcing. In most developed countries, screening test recommendations encourage periodic testing. Therefore, patients are continuing their screening. It is necessary for patients to become wise consumers of screening tests and make decisions with their physicians regarding further testing and treatments.

Keywords: Cancer screening; Overdiagnosis; Overtreatment.