What Is Melanoma?
The most dangerous form of skin cancer, these cancerous growths develop when unrepaired DNA damage to skin cells (most often caused by ultraviolet radiation from sunshine or tanning beds) triggers mutations (genetic defects) that lead the skin cells to multiply rapidly and form malignant tumors. These tumors originate in the pigment-producing melanocytes in the basal layer of the epidermis. Melanomas often resemble moles; some develop from moles. The majority of melanomas are black or brown, but they can also be skin-colored, pink, red, purple, blue or white. Melanoma is caused mainly by intense, occasional UV exposure (frequently leading to sunburn), especially in those who are genetically predisposed to the disease. Melanoma kills an estimated 10,130 people in the US annually.
If melanoma is recognized and treated early, it is almost always curable, but if it is not, the cancer can advance and spread to other parts of the body, where it becomes hard to treat and can be fatal. While it is not the most common of the skin cancers, it causes the most deaths. In 2016, an estimated 76,380 of these will be invasive melanomas, with about 46,870 in males and 29,510 in women.
Moles, brown spots and growths on the skin are usually harmless — but not always. Anyone who has more than 100 moles is at greater risk for melanoma. The first signs can appear in one or more atypical moles. That’s why it’s so important to get to know your skin very well and to recognize any changes in the moles on your body. Look for the ABCDE signs of melanoma, and if you see one or more, make an appointment with a physician immediately.
There are three general categories of melanoma:
- Cutaneous Melanoma is melanoma of the skin. Since most pigment cells are found in the skin, cutaneous melanoma is the most common type of melanoma. Cutaneous melanoma can be described in four main ways:
- Superficial Spreading Melanoma
- Nodular Melanoma
- Acral Lentiginous Melanoma
- Lentigo Maligna Melanoma
- Mucosal Melanoma can occur in any mucous membrane of the body, including the nasal passages, the throat, the vagina, the anus, or in the mouth
- Ocular Melanoma, also known as uveal melanoma or choroidal melanoma, is a rare form of melanoma that occurs in the eye. Learn more about CURE OM, the MRF’s initiative focused on ocular melanoma
Unlike other cancers, melanoma can often be seen on the skin, making it easier to detect in its early stages. If left undetected, however, melanoma can spread to distant sites or distant organs. Once melanoma has spread to other parts of the body (known as stage IV), it is referred to asmetastatic melanoma, and is very difficult to treat. In its later stages, melanoma most commonly spreads to the liver, lungs, bones and brain; at this point, the prognosis is very poor.
What causes melanoma?
Research suggests that approximately 90% of melanoma cases can be linked to exposure to ultraviolet (UV) rays from natural or artificial sources, such as sunlight and indoor tanning beds. However, since melanoma can occur in all melanocytes throughout the body, even those that are never exposed to the sun, UV light cannot be solely responsible for a diagnosis, especially mucosal and ocular melanoma cases. Current research points to a combination of family history, genetics and environmental factors that are also to blame. Read our Melanoma Fact Sheet for more information!