Non-melanoma skin cancer (NMSC) causes more deaths globally each year than melanoma, which is considered a more aggressive form of skin cancer, shows research presented this week at the European Academy of Dermatology and Venerology Congress 2023.
The higher number of deaths can be attributed to the substantially higher incidence of NMSC, but the fact that the disease can be treated more easily than melanoma should not mean that clinicians disregard its potential severity.
“We have to get the message out that not only can melanoma be fatal, but NMSC also. There is a need to implement effective strategies to reduce the fatalities associated with all kinds of skin cancers,” says Professor Thierry Passeron, from University Hospital Centre Nice, France, who led the study in collaboration with researchers from La Roche-Posay International.
Using WHO International Agency for Research on Cancer data, Passeron and team showed that there were more than 1.5 million cases of skin cancer diagnosed worldwide in 2020, and 135,860 deaths.
Incidence and mortality rates per 100,000 people were highest in Oceania (208.9 and 7.4, respectively), North America (116.8 and 2.3), and Europe (67.9 and 5.3), which Passeron said is likely due to having the highest number of White and elderly population groups in these geographies.
However, he noted that the highest mortality-to-incidence ratios were observed in Asia and Africa, at 0.36 and 0.33, respectively, compared with a ratio of below 0.02 for Oceania, North America, and Europe.
“Although Caucasians have the highest skin cancer incidence, African and Asian nations face a mortality rate almost seven times higher than Western countries, indicating significant healthcare disparities and we have to fight against this,” Passeron remarks.
Looking at the different types of skin cancer, melanoma accounted for 324,635 cases and 57,043 deaths, while NMSC, including squamous cell carcinoma, basal cell carcinoma, and Merkel cell carcinoma, numbered 1.2 million cases and 63,731 deaths.
This shows that more than half of global skin cancer deaths are due to NMSC, but Passeron cautioned that the numbers may be underreported, particularly in Black and Asian populations. He noted that a “recent study in the US estimated that more than 3 million people were treated for a NMSC in 2012, a number six times higher than the IARC incidence data in 2020. This inconsistency underscores the important issue of underreporting for NMSC.”
Passeron and team also analyzed the data according to specific risk factors for skin cancers and found that people with albinism, those with HIV, outdoor workers, elderly people, and people who take part in indoor tanning are at particularly high risk for NMSC. “In my opinion those are populations where we can do [with] better in terms of prevention,” he says.
Finally, the investigators studied how access to dermatologists impacted melanoma mortality. Passeron reported that, at 7.3 dermatologists per 100,000 people, Europe had the highest density of dermatologists and was well above the average (based on data from 59 countries) of 2.8. Asian and African countries had the lowest density at 1.6 and 2.3 per 100,000.
Yet he says the way in which different countries deal with the public health problem of skin cancer differs greatly from one country to another. “Germany and Italy face high incidence rates with a relatively high density of dermatologists. While high incidence rates in Australia, the U.K., Canada, is addressed with a low density of dermatologists,” Passeron notes.
He continues: “Countries like Canada, U.K., and Australia have lower dermatologist density as well as lower mortality-to-incidence ratio suggesting better awareness, patient care, and early detection programs, unlike Japan, Russia, and Argentina, where mortality-to-incidence is much higher despite their high density of dermatologists.”
Passeron suggests that the involvement of other healthcare professionals, such as general practitioners (GPs) may partially explain the success observed in Canada, UK, and Australia, and said that training GPs to recognize and manage skin cancers could be a model for other countries.