Early success for Australia’s bowel screening program: let’s move it along
Cancer screening programs are under scrutiny. Ultimately, the measure of success is whether the program saves lives by detecting precancerous lesions or early-stage cancers that have a high cure rate.
This must be achieved by a test that can feasibly be offered to whole populations, is acceptable to large population cohorts and reduces mortality with minimal harm. Harm in this context refers to overdiagnosis — detecting cancers or suspected cancers that would have caused no significant morbidity in the patient’s lifetime. This differs from an incorrect diagnosis, but needs to be considered when weighing the risks and benefits of every screening program. A common harm of overdiagnosis is that it can lead to patients having invasive treatment, often with side effects, for no survival benefit (overtreatment). Psychological distress is also a significant harm of overdiagnosis.
The balance of risks and benefits is at the core of why prostate-specific antigen testing is not recommended as a population screening test for prostate cancer.1
The benefits of breast screening have also been questioned, partly because advances in treatment have coincided with population-based mammographic screening — making the relative contributions of each to improved survival difficult to measure. However, breast screening is still recommended when benefit is balanced against risk.2