Skin neoplasms (also known as "skin cancer") are skin growths with differing causes and varying degrees of malignancy. The three most common malignant skin cancers are basal cell cancer, squamous cell cancer, and melanoma, each of which is named after the type of skin cell from which it arises..
Skin cancer generally develops in the epidermis (the outermost layer of skin), so a tumor can usually be seen. This means that it is often possible to detect skin cancers at an early stage. Unlike many other cancers, including those originating in the lung, pancreas, and stomach, only a small minority of those affected will actually die of the disease, though it can be disfiguring. Melanoma survival rates are poorer than for non-melanoma skin cancer, although when melanoma is diagnosed at an early stage, treatment is easier and more people survive.
Skin cancer is the most commonly diagnosed type of cancer. Melanoma and non-melanoma skin cancers combined are more common than lung, breast, colorectal, and prostate cancer. Melanoma is less common than both basal cell carcinoma and squamous cell carcinoma, but it is the most serious — for example, in the UK there were over 11,700 new cases of melanoma in 2008, and over 2,000 deaths. 59,695 people in the United States were diagnosed with melanomas of the skin, including 38,484 men and 25,211 women. 8,623 people in the United States died from melanomas of the skin, including 5,672 men and 2,951 women.
It is the second most common cancer in young adults aged 15–34 in the UK. Most cases are caused by over-exposure to UV rays from the sun or sunbeds. Non-melanoma skin cancers are the most common skin cancers. The majority of these are basal cell carcinomas. These are usually localized growths caused by excessive cumulative exposure to the sun and do not tend to spread.
MelanomaMelanoma i/ˌmɛləˈnoʊmə/ (from Greek μέλας — melas, "dark") is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel, oral cavity and the eye (see uveal melanoma). Melanoma can originate in any part of the body that contains melanocytes. Melanoma is less common than other skin cancers. However, it is much more dangerous if it is not found early. It causes the majority (75%) of deaths related to skin cancer.
Worldwide, doctors diagnose about 160,000 new cases of melanoma yearly. It is more common in women than in men. In women, the most common site is the legs and melanomas in men are most common on the back. It is particularly common among Caucasians, especially northern Europeans living in sunny climates. There are high rates of incidence in Australia, New Zealand, North America (especially Texas and Florida), Latin America, and Northern Europe, with a paradoxical decrease in southern Italy and Sicily. This geographic pattern reflects the primary cause, ultraviolet light (UV) exposure crossed with the amount of skin pigmentation in the population.
According to a WHO report, about 48,000 melanoma related deaths occur worldwide per year. The treatment includes surgical removal of the tumor. If melanoma is found early, while it is still small and thin, and if it is completely removed, then the chance of cure is high. The likelihood of the melanoma coming back or spreading depends on how deeply it has gone into the layers of the skin. For melanomas that come back or spread, treatments include chemo- and immunotherapy, or radiation therapy.