Melanoma crash course

Cutaneous melanoma represents about 4% of skin cancers but is responsible for more than 75% of deaths from skin cancer. The incidence of cutaneous melanoma is reported as 25 per 100,000 people in North America and 60 per 100,000 people in Australia and New Zealand. Melanoma diagnoses are increasing worldwide, possibly owing to improved detection; in Canada the largest increase in age-standardized incidence of melanoma has occurred in males, with an increase of 2.2% per year between 1984 and 2019. Mortality rates for melanoma have declined since 2013 due to the use of immunotherapy; however, there has been no noted reduction in mortality among non-White patients or among populations with lower socioeconomic status, with a study demonstrating that these populations have higher incidences of thick melanoma with poorer prognoses.

There is insufficient evidence to support the effectiveness of skin cancer screening in reducing melanoma mortality, with an Australian study published in 2022 finding that skin screening increases the risks of biopsy and melanoma in situ without increasing the detection rate of invasive melanoma, compared with unscreened individuals. The United States Preventive Services Task Force also does not recommend regular skin checks in the average individual as part of age-appropriate screening guidelines. A guideline published by the Canadian Task Force on Preventive Health Care, based on reports from Australia and New Zealand, recommends regular skin examinations for those at high risk of melanoma (Table 1).