Note: Separate PDQ summaries on Skin Cancer Prevention, Skin Cancer Treatment, and Levels of Evidence for Cancer Screening and Prevention Studies are also available.
The only widely proposed screening procedure for skin cancer is visual examination of the skin, including both self-examination and clinical examination.
In asymptomatic populations, the effect of visual skin examination on mortality from nonmelanomatous skin cancers is unknown. Further, the evidence is inadequate to determine whether visual examination of the skin in asymptomatic individuals would lead to a reduction in mortality from melanomatous skin cancer.
Magnitude of Effect: Not applicable (N/A).
- Study Design: Evidence obtained from a single case-control study.
- Internal Validity: Poor.
- Consistency: N/A.
- External Validity: N/A.
Based on fair though unquantified evidence, visual examination of the skin in asymptomatic individuals may lead to unavoidable increases in harmful consequences. These include complications of diagnostic or treatment interventions (including extensive surgery) and the psychological effects of being labeled with a potentially fatal disease. Another harmful consequence is overdiagnosis leading to the detection of biologically benign disease that would otherwise go undetected, and the possibility of misdiagnosis of a benign lesion as malignant.
Magnitude of Effect: Unknown.
- Study Design: Opinions of respected authorities based on clinical experience, descriptive studies, or reports of expert committees.
- Internal Validity: Fair.
- Consistency: Multiple studies; small number of participants—no consistency.
- External Validity: Fair.