The cause of this type of cancer is not entirely known. Yes, certain factors that influence its appearance have been studied.
Environmental factors
Excessive exposure to the sun influences the production of these cancers. People who work abroad, such as farmers and sailors, have a higher incidence. They usually occur on exposed skin, frequently on the head and neck.
Although sunlight helps synthesize vitamins A and D, excessive exposure, whether or not it causes burns, increases the risk of developing skin cancer, including malignant melanoma.
There is a correlation between the risk of melanoma and latitude. It also influences the period of time for which a person has lived in countries of Ecuadorian latitudes, which means excessive exposure to the sun maintained over a period of life.
Not only is prolonged exposure influencing, but intense, occasional exposure to the sun, during a vacation, for example, constitutes a risk factor for both basal cell carcinoma and melanoma.
Melanomas differ from malignant non-melanoma skin tumors with respect to sex, age, and body location. Most cutaneous malignant melanomas do not occur in areas receiving the highest cumulative ultraviolet dose.
Although the most dangerous scheme of sun exposure is not known exactly, some studies support the hypothesis that intense and intermittent exposure to normally protected ultraviolet radiation from the skin is responsible for the formation of melanoma.
Age also seems to play a role, and sunburns before age 15 double the risk of melanoma.
Physical characteristics
White people of Scottish, English, or Irish descent with blonde or reddish hair, light eyes, and abundant freckles are especially susceptible.
Melanoma is very rare in the black or eastern population, being predominant, when it occurs, in poorly pigmented areas such as palms and soles and its prognosis is worse.
The sensitivity of the skin to the sun and the difficulty of tanning, increases the risk of melanoma.
The skin reaction to sunlight is related to factors such as skin pigmentation, the number of freckles in childhood or adulthood, and the number of nevi (mole-like formations that are benign melanocytic tumors), all constituting factors risks for cutaneous malignant melanoma.
The higher incidence of nevi in white individuals leads to the idea that ultraviolet radiation plays an important role in the development of nevi. The existence of a greater number of nevi in areas of the skin exposed to the sun than in protected areas has been verified, its increase being associated with a greater propensity to burn than to tan, the number of sunburn, the tendency to freckles and style. life related to increased sun exposure. A person with sun-sensitive skin, more than 150 melanocytic nevi and some dysplastic nevus (with a microscopic appearance similar to malignant melanoma cells), could be 50 times more at risk of melanoma than another person without these characteristics.
Genetic factors
Nevoid basal cell carcinoma syndrome is an inherited disorder in which patients develop a large number of basal cell carcinomas from the second decade of life and, ultimately, affect any area of the skin.
Xeroderma pigmentosum is an inherited disorder that occurs due to an alteration in DNA repair, it is also associated with the appearance of multiple cutaneous carcinomas.
A familial predisposition has been described in cutaneous malignant melanoma. The estimated risk of presenting it is 70% in patients with neurocutaneous melanosis and different types of xeroderma pigmentosum, 1% in children of patients with nonfamilial solitary melanoma and 6% in families with dysplastic nevus syndrome and a history of two or more. malignant melanomas.
Immunosuppression
Those people who have been treated with medicines that depress their immune systems are more likely to develop melanoma.
Overexposure to tanning lamps and booths
Tanning lamps and booths are a source of ultraviolet radiation. Excessive exposure increases the risk of developing skin cancer.
Age
About half the number of melanoma cases occurs in people over the age of 50.
Other factors
Exposure to carcinogens, trauma or scarring, chronic radiation injuries, and viral infections are some of the factors that predispose the appearance of skin cancer.