Skin cancer begins in the cells that make up the outer layer (epidermis) of your skin. Skin cancer — the abnormal growth of skin cells — most often develops on skin exposed to the sun. But skin cancer cells can also occur on areas of your skin not ordinarily exposed to sunlight.
There are 3 types of skin cancer that typically impact older people:
- Melanoma
- Basal cell skin cancer
- Squamous cell skin cancer
Melanoma is more aggressive than basal cell skin cancer or squamous cell skin cancer.
What is Melanoma?
Melanoma is a disease in which malignant (cancer) cells form in the skin cells called melanocytes (cells that color the skin). Melanocytes are found throughout the lower part of the epidermis. They make melanin, the pigment that gives skin its natural color. When skin is exposed to the sun, melanocytes make more pigment, causing the skin to tan, or darken.
The skin is the body's largest organ. It protects against heat, sunlight, injury, and infection. The skin has 2 main layers: the epidermis (upper or outer layer) and the dermis (lower or inner layer). When melanoma starts in the skin, the disease is called cutaneous melanoma.
Melanoma can occur anywhere on the body. In men, melanoma is often found on the trunk (the area from the shoulders to the hips) or the head and neck. In women, melanoma often develops on the arms and legs.
Melanoma Risk Factors
Risk factors for melanoma include the following:
- Unusual moles.
- Exposure to natural sunlight.
- Exposure to artificial ultraviolet light (tanning booth).
- Family or personal history of melanoma.
- Being white and older than 20 years.
- Red or blond hair.
- White or light-colored skin and freckles.
- Blue eyes.
Melanoma Warning Signs
To be on the lookout for skin cancer, check moles twice a year. Here are some warning signs to look for:
- A change in the appearance, including the size, shape and color of a mole or pigmented area.
- Moles with irregular edges or borders
- More than one color in a mole
- An asymmetrical mole (if the mole is divided in half, the 2 halves are different in size or shape)
- Itches, oozes or bleeds
- Ulcerated (a hole forms in the skin when the top layer of cells breaks down and the underlying tissue shows through).
- Change in pigmented (colored) skin.
- Satellite moles (new moles that grow near an existing mole).