Melanoma is a malignant tumor of the melanin cells that give the skin its color. It is the most serious form of skin cancer. The incidence of melanoma is on the rise but advances in treatment have improved treatment and survival. It is the most common skin cancer in young women, the fifth most common type of cancer in men, and the sixth most common cancer in women.
Melanoma can develop within or adjacent to an existing mole. About 25% of melanomas arise in a preexisting mole. The majority of melanomas arise on normal skin. Melanoma accounts for only 1% of skin cancers but results in a majority of skin cancer deaths. Early detection and prevention are keys to reducing the risk of serious illness and death.
What are the risk factors for developing melanoma?
- Ultraviolet radiation from sunlight and tanning beds is the main environmental risk factor. The risk of developing melanoma doubles with a history of five or more sunburns in childhood or adolescence.
- Individuals with red or blond hair, light complexion and light eyes are at greatest risk. Melanoma is 20 times more common in whites than African Americans.
- Having many moles (10 or more) is the strongest predictor of developing melanoma in fair skinned individuals.
- Developing new moles after age 50.
- Having atypical moles that look like melanoma can increase the risk.
- A family history of melanoma.
- Having a weak immune system.
What causes melanoma?
Melanoma is caused by DNA damaged in skin cells that allows the skin cells to grow out of control. The cause of DNA damage is multi-factorial, meaning a combination of risk factors combined cause melanoma. UV light can cause melanoma, but it can also be found on skin that has not been exposed to UV light, including in the mouth, nose and genitals, on palms of the hands and soles of the feet, in the eye and in the nail bed of fingernails and toenails.
What are the different types of melanoma?
There are four main types of melanoma:
- Superficial spreading melanoma is the most common type accounting for 70% of cases. It is very curable if diagnosed early. It tends to grow on the surface of the skin but over time it penetrates more deeply. It is most often found on the legs and upper back of a woman and the chests or backs of men. People under age 40 who develop melanoma are the superficial spreading type.
The usual presentation is a flat or slightly raised lesion that is asymmetrical with uneven borders and various shades of tan, brown, black, pink, red, blue or white. UV radiation from the sun and tanning beds increase the risk of this type of melanoma.
- Nodular melanomas are the most aggressive type that grows fast and deep into the skin. It usually develops on the scalp, torso, legs and arms of older white men. About 15% of cases are nodular melanoma. It is identified by a bump that is usually blue black but can appear as a red or pink bump.
- Lentigo maligna melanoma is a form of melanoma that typically affects older people. Initially it grows on the skin’s surface but can become invasive. It normally occurs on sun damaged skin. It appears as a flat or slightly raised lesion with uneven borders and a blue-black color.
- Acral lentiginous melanoma is the type that most often affects people of color. It often grows under the nails and on the soles of the feet and palms of the hands. It often appears as a black or brown spot.
How is melanoma diagnosed?
Your dermatologist at Lucent Dermatology will inquire about your symptoms, when you first noted changes and what changed. They will review your personal and family medical history, history of tanning and sun exposure, and check your body for moles. Dr. Alexandra Zhang or Dr. William Camp will examine the lesion based on the ABCDE rules about the usual signs of melanoma – asymmetry, irregular borders, uneven and multiple colors, the diameter of the lesion and whether is it evolving in size, shape, or color. They may feel your lymph glands for enlargement, as this may be a sign of spread.
Any suspicious spots will be biopsied, and the tissue sent to a lab to identify the type of melanoma and stage the tumor – how deep and how far the melanoma has spread. When the diagnosis is melanoma, they may order a sentinel node biopsy to check whether the cancer has spread to the lymph nodes. If there is concern that melanoma has spread or you are at high risk, imaging tests may be ordered including a chest x-ray because melanoma often spreads to the lungs.
What are the treatments for melanoma?
Treatment options are based on the depth and extent of the tumor, the stage of the tumor and its growth rate, your overall health, and other considerations. It usually involves surgery to remove the tumor and if it has spread more advanced treatments will be offered.