Experts analyze the causes of malignant melanoma

Malignant melanoma is a surgical disease caused by many factors, which brings great harm to people's health. What are the common causes of malignant melanoma ? Here are some common causes of malignant melanoma.

Common causes of malignant melanoma include:

1. Sunlight and ultraviolet radiation. Ultraviolet radiation is the main factor causing malignant melanoma. Ultraviolet radiation is very sensitive to DNA damage and can lead to a decrease in systemic immunity. Many data support the pathogenic effects of sunlight and ultraviolet radiation. Some people believe that there is insufficient evidence that sunlight causes malignant melanoma, and propose the sunlight cycle factor hypothesis, which believes that sunlight exposure causes the body to produce a factor that circulates with the blood to other parts of the body, stimulating melanocytes to become malignant. This hypothesis has yet to be confirmed, but the argument that sunlight and ultraviolet radiation cause malignant melanoma is still recognized by people.

2. Racial genetic factors. The incidence of malignant melanoma in white Americans is higher than that in blacks. The incidence of malignant melanoma in Japanese is lower than that in whites. However, the incidence of malignant melanoma in Australians, especially the Celtic people from the UK, is the highest. Among human patients with malignant melanoma, 1% to 6% have a family history. The proportion of multiple malignant melanomas with a family history can be as high as 44%, which is an autosomal dominant inheritance. Greene collected 34 literature data, with a total of 450 cases of familial malignant melanoma in the skin, distributed in 155 families, with an average of 3 cases per family, and the largest family had 15 patients. All cases occurred in white people. 67% of malignant melanomas develop on existing moles, and familial malignant melanomas are increasing. Epidemiological data also show that the incidence of malignant melanoma in white people is significantly higher than that of people of color.

3. Malignant transformation of existing pigmented nevi. 60% of malignant melanomas are caused by benign nevi. The malignant transformation rate of congenital giant nevi is as high as 10% to 30%. Some people believe that those with more than 20 skin nevi have a 3-fold higher risk of malignant transformation. It is well known that junctional nevi and junctional components in mixed nevi can be malignantly transformed into melanoma. Junctional nevi are mainly the phenotype of pigmented nevi on the skin of infants or children. They rarely become malignant before puberty. After puberty, most junctional nevi have been transformed into intradermal nevi. Only a few parts such as the palms, soles, scrotum, and labia still retain the characteristics of junctional nevi in ​​adults. Therefore, these nevi have the greatest potential for malignant transformation. Intradermal nevi are generally considered to be benign and will not undergo malignant transformation, but there are now reports of malignant transformation of intradermal nevi.

4. Endocrine factors. It has long been believed that pregnancy can stimulate the malignant transformation of moles, or aggravate existing malignant melanomas, leading to poor prognosis. There is no definite conclusion on the relationship between the increase of estrogen and the occurrence of malignant melanoma. The presence of estrogen receptors in melanoma cells indicates that it has a certain relationship with the pathology of malignant melanoma. The formation of melanin is due to the catalysis of tyrosine oxidation by tyrosine, which forms malignant melanoma. Glutathione in the human body can indirectly inhibit the activity of tyrosinase, while estrogen and progesterone can counteract the effect of glutathione, resulting in increased melanin production. Therefore, it is believed that endocrine has a certain relationship with the formation of malignant melanoma.

The above is an introduction to the common causes of malignant melanoma. I hope it will be helpful to everyone. Once you have malignant melanoma, you must go to the hospital for treatment in time to avoid serious delays in the disease.