More than half of all melanoma diagnoses among white Americans may be overdiagnoses, according to a new study in BMJ Evidence-Based Medicine.
For the study, researchers collected incidence and mortality data from the Surveillance, Epidemiology and End Results 9 registries database. They also used DevCan software to calculate the cumulative lifetime risk of being diagnosed with melanoma between 1975 and 2018, with adjustments made for changes in longevity and risk factors over the study period.
The upshot? An estimated 49.7% of melanomas diagnosed in white men and 64.6% in white women were overdiagnosed in 2018—a total of about 83,000 cases. The data also show that the lifetime risk of being overdiagnosed with melanoma increased over the years.
“Cases of cutaneous melanoma have risen significantly in the U.S. over the last 40 years, without an equivalent rise in mortality— which points to overdiagnosis,” says study author Ade Adamson, MD, an assistant professor in the Department of Internal Medicine at Dell Medical School at the University of Texas at Austin, in a news release. “That means the patient may undergo expensive, unnecessary treatments that may do far more harm than good.”
A large proportion of overdiagnosed melanomas are in the earliest stage (Stage 0 – also known as melanoma in situ). The authors estimate that 89% of melanoma in situ are overdiagnosed in white men and 85% in white women in the US.
“This study shouldn’t dissuade people from getting concerning moles evaluated for melanoma, especially if you are high risk,” says Adamson. “However, my hope is that it informs how people receive a melanoma diagnosis and brings awareness to the phenomenon of overdiagnosis an unintended consequence of screening.”
