Nonmelanoma skin cancers: 'Alarming' incidence rates may be underestimated, underreported

Key Points

World report - The incidence rates of nonmelanoma skin cancers, as well as malignant melanoma, are reaching alarmingly high levels worldwide, and this disturbing rise is associated with the increase in ultraviolet exposure for the general population.

According to one expert, the incidence of these cancers observed in epidemiologic studies are, in reality, higher than recorded - an even more alarming development.

"Nonmelanoma skin cancer is on a steady rise, which is an alarming fact in itself. However, what is even more alarming is that the rates of increased incidence may be underestimated, making this problem even bigger than first assumed," says Thomas Diepgen, M.D., professor, department of social medicine, occupational and environmental dermatology, Medical University Hospital, Heidelberg, Germany.

Inaccurate data

One reason for this is that most of the studies concerning the incidence rates of these cancers are based on general cancer registries.

According to Dr. Diepgen, there is some evidence that indicates that there is some underrepresentation in these cancer registries, resulting in statistics that are far off the mark.

Dr. Diepgen reviewed some studies from Australia, comparing epidemiological data using cancer registries, and found that they clearly demonstrate an underestimation of the actual incidence of nonmelanoma skin cancers.

In Australia, the prevalence of nonmelanoma skin cancer is between 1 percent and 2 percent, which is quite high.

According to Dr. Diepgen, the prevalence of these cancers in Europe may not be as high as in Australia; nevertheless, the under-estimation of these skin cancers occurs in Europe, as well.

Dr. Diepgen says exposure to ultraviolet light is a worrisome reality in a lot of outdoor occupations.

Health professionals have now recognized that ultraviolet light-induced skin cancer is an occupational disease, and importantly, it is not only a disease of those individuals who take vacations in sunny climates and expose themselves to the ultraviolet light in their free time, but also a disease to be reckoned with in those individuals who work outdoors.

"Here in Germany, we are fighting to establish that ultraviolet light-induced nonmelanoma skin cancers, as well as lentigo maligna type of melanoma, are officially considered as an occupational disease and an occupational hazard.

"This is important, especially because of the possibilities of prevention, as most of the occupations which involve working under the rays of the sun, these nonmelanoma skin cancers are preventable if the proper precautions are taken," Dr. Diepgen tells Dermatology Times.

According to Dr. Diepgen, nonmelanoma skin cancers can be prevented if a pro-active approach is taken, and the sooner, the better.

Individuals who work outdoors could be supplied with sunscreens as well as special textiles or clothing to help them protect themselves from harmful ultraviolet exposure.

Also, a screening program for these individuals could and should be set into motion, Dr. Diepgen says.

"The early detection of nonmelanoma skin cancer and melanoma is crucial, as the prognosis of the individual directly depends on the timing of the detection of the cancer lesion. The incidence of such cancers could be decreased if a simple screening program were initiated," he says.

According to Dr. Diepgen, this could be achieved with the proper organization, as well as enough dermatologists to do the actual screening.

If such a program were to be started, then the incidence rates of skin cancers in individuals who are exposed to this occupational hazard in the form of excessive ultraviolet radiation could be kept down.

Dr. Diepgen says the increase of nonmelanoma skin cancer from year to year is estimated to be 2 percent to 3 percent, and in 10 to 20 years, this figure is projected to double.

According to Dr. Diepgen, the repercussions of this increasingly worrisome trend could possibly be dampened in the sense of damage control, if the proper and timely measures are taken to protect these individuals from the harmful ultraviolet radiation that they are exposed to on a regular basis.