A UK Study Shows That the Incidence of Skin Cancer Has Exploded in 40 Years

Sunbathing on the beach in the summer is not safe because the sun’s UV rays can cause cancer. British doctors have quantified the incidence of skin melanoma for 40 years and the news is not good.

Melanoma

In Western societies, a tanned body is synonymous with good health and is considered more desirable. However, prolonged sun exposure is not without health risks. UV rays (UVA and UVB) penetrate our epidermis and stimulate melanocytes, which then produce melanin, a pigment that protects the skin from radiation and gives the skin its tanned appearance. UV rays, especially UVB rays with a wavelength between 315 and 280 nanometers, are also mutagenic agents that alter the nature of the chemical bonds between the bases of DNA.

The best-known phenomenon that leads to skin cancer has to do with the occurrence of double carbon-carbon bonds between two consecutive thymines in the same DNA chain. This abnormal pairing leads to the transformation of a normal cell into a cancer cell if not repaired. Exposure to UV rays causes 86% of malignant melanomas of the skin, a type of skin cancer that affects melanocytes.

Doctors from the Medical University of Brighton in Sussex have studied the incidence of melanoma in their country. Their epidemiological analysis is based on the study of 265,302 cases of skin melanoma diagnosed in fair skin between 1980 and 2018. And the results are worrying: in forty years, the incidence rate has increased by 700% in men and 332% in women. Their paper appeared in The Lancet Regional Health.

Increasing incidence of skin cancer in the elderly

Although the incidence of skin melanoma has increased dramatically since 1980, the trend is not the same in all age groups. The English Physicians divided the group into three age groups: 0-34 years, 34-64 years, and 65 years and older. In the 0-34 age group, the incidence of skin melanoma increased until 2005, before stabilizing at about 1,300 cases per 100,000 population per year. It actually decreased slightly between 2016 and 2018. This trend is comparable between men and women, with the latter more affected by the disease.

In contrast, skin melanomas have increased worryingly among those over 65 years of age. Between 1980 and 2018, their incidence increased by 842 percent in men and 383 percent in women and continues to increase while decreasing in other age groups.

The trunk and legs are particularly affected

Doctors have also observed the occurrence of skin melanomas in different parts of the body. Not surprisingly, those parts most frequently exposed to the sun are the most affected. In men, the trunk is the most affected part of the body, followed by the lower limbs, then the upper limbs, and finally the head and neck. In women, the pattern is slightly different. The lower limbs are most exposed, but since 1996 there has been a sharp increase in malignant cancers of the trunk.

Fortunately, mortality associated with melanoma has not increased at the same rate. Over the past forty years, the mortality rate per 100,000 people has increased 117% in men and 32% in women.

Skin melanomas are preventable, thanks to simple things that could be done to limit UV exposure. In their study, the authors emphasize that prevention campaigns against the harmful effects of the sun are useful because, for the first time, the incidence of skin melanoma is stabilizing in the under-34 age group.