A meta-analysis of six common cancer screenings has concluded that “current evidence does not substantiate the claim that common cancer screening tests save lives by extending lifetime, except possibly for colorectal cancer screening with sigmoidoscopy.”
Michael Bretthauer and colleagues from the University of Oslo reported in JAMA Internal Medicine that screening benefits were small: a statistically significant 110 days’ gain was seen with colorectal cancer screening with sigmoidoscopy.1 Gains were 37 days with prostate cancer screening and colonoscopy and 107 days with lung cancer screening. No days were gained with mammography or faecal occult blood testing.
The authors did not call for abandoning all screening but said that it was important for organisations and policy makers “to provide the public with reliable estimates for benefits and harms of screening on cancer incidence and mortality and on lifetime gained by screening.”
Organised cancer screening programmes have been set up in Europe, Canada, the Pacific Islands, and many countries in Asia. In the US cancer screening is encouraged by many organisations and is usually reimbursed by insurance companies. However, the researchers said that few of these programmes had presented their results as practical estimates on how much cancer screening may increase life expectancy. “Our study provides these …