Early detection is the primary goal of cancer screening programs to reduce morbidity and mortality. However, it leads to overdiagnosis quite often. Overdiagnosis, which involves the discovery of life-threatening tumors, can have negative consequences, such as increased anxiety throughout the diagnostic process. Without conclusive evidence from randomized clinical studies, the benefits and dangers of melanoma screening remain debatable.

Using a propensity score-based analysis, Whiteman and colleagues found that the cumulative risk difference grew with time to a 0.5% absolute risk difference after 5 years (screened 1.94%, unscreened 1.45%). In situ melanomas accounted for more than 60% of new diagnoses. When the primary analysis was limited to invasive melanomas, the difference between screened and unscreened vanished (adjusted hazard ratio 1.05, 95% confidence interval 0.72-1.63). These data support the hypothesis that screening leads to overdiagnosis of melanoma in situ.

Routine skin exams may not prevent advanced melanoma and death as hoped, according to epidemiological research. Such efforts are essential to avoid risks from early melanoma identification and assure high-value health care. Given the potential of melanoma overdiagnosis, screening may be most effective for people at the highest risk of advanced-stage disease or death.

Source: Bell KJL, Nijsten T. Melanoma overdiagnosis: why it matters and what can be done about it. Br J Dermatol. 2022;187(4):459-60.