Global incidence, mortality, risk factors and trends of melanoma: a systematic analysis of registries

Background: Melanoma of the skin is the most dangerous skin cancer in the world, though the numbers of reported new cases and melanoma-related deaths are low. Objective: This study evaluated the global incidence, mortality, risk factors and temporal trends by age, sex and locations of melanoma skin cancer. Patients and Methods: Cancer Incidence in Five Continents (CI5) volumes I–XI; the Nordic Cancer Registries (NORDCAN); the Surveillance, Epidemiology and End Results (SEER) Program; and the World Health Organization (WHO) International Agency for Research on Cancer (IARC) mortality database were accessed for worldwide incidence and mortality rates. Average Annual Percentage Change (AAPC) was calculated using a Joinpoint regression to examine trends. Results: Age-standardized rates of cancer incidence and mortality were 3.4 and 0.55 per 100,000 worldwide in 2020. Australia and New Zealand reported the highest incidence and mortality rates. Associated risk factors included higher prevalence of smoking, alcohol consumption, unhealthy diet, obesity and metabolic diseases. Increasing incidence trends were observed mostly in European countries, whilst mortality displayed an overall decreasing trend. For both sexes in the age group 50 years and above, a significant increase in incidence trend was observed. Conclusions: Although mortality rates and trends were found to decrease, global incidence has increased, especially in older age groups and males. Whilst incidence increase may be attributed to improved healthcare infrastructure and cancer detection methods, the growing prevalence of lifestyle and metabolic risk factors in developed countries should not be discounted. Future research should explore underlying variables behind epidemiological trends.