Most cases of melanoma, the deadliest type of skin cancer, are caused by exposure to ultraviolet (UV) light from the sun, tanning beds, or sunlamps.
UV rays are a form of invisible radiation that can penetrate skin and change skin cells.
Of the three types of UV rays — UVA, UVB, and UVC — UVA rays are considered the most dangerous when it comes to increasing the risk of skin cancer.
Prevalence
According to the American Cancer Society (ACS), 76,690 Americans — roughly 60 percent of them men — were diagnosed with melanomas of the skin in 2013.
Another 5,880 were diagnosed with what are known as non-epithelial skin cancers, such as sarcomas.
The ACS reports that nearly 12,000 Americans die each year from melanomas and non-epithelial skin cancers.
These figures do not include basal cell and squamous cell carcinomas, two other common forms of skin (explained below).
Types of Skin Cancer
There are several types of skin cancer, including:
Melanoma: A melanoma is a cancerous growth that most frequently develops in the skin.
This type of growth can also form in any part of the body that contains melanocyte cells, including the digestive tract, eyes, lymph nodes, and meninges (membranes lining the brain and spinal cord).
Basal cell carcinoma (BCC): BCC is the most commonly diagnosed skin cancer.
It can develop on regions of the body that receive regular sun exposure, including the face and hands.
Fortunately, BCC rarely spreads and is usually treatable, due to its slow growth rate.
A common form of BCC is nodular basal cell carcinoma. In nodular BCC, lesions typically appear brown, black, or blue in color.
Squamous cell carcinoma (SCC): SCC appears on body parts that have experienced higher levels of sun exposure, including the face, lips, and back.
Lesions can appear rough, scaly, lumpy, or flat, and they may bleed easily.
SCC is more likely to spread than BCC.
Merkel cell carcinoma (MCC): MCC, also known as neuroendocrine carcinoma, is a rare type of skin cancer.
Lesions can be flesh-colored or bluish-red, and they can develop on your face, head, or neck.
Kaposi sarcoma (KS): KS lesions can grow under the skin; in the lining of the mouth, nose, and throat; or in other body organs.
In recent years, they have been associated withHIV/AIDS, but there are other causes of KS, including other infections.
KS lesions typically appear red or purple in color and are made of both cancer cells and blood cells. They may be painful.
Epidermoid cysts: Sometimes called sebaceous cysts (although they are actually different), epidermoid cysts are noncancerous.
They appear as small bumps beneath the skin, most often on the face, neck, and torso.
Sebaceous cysts are less common. They arise from sebaceous glands, which secrete oily matter that lubricates your hair and skin.
Risk Factors
Risk factors vary for different types of skin cancer. However, any of the following can increase your risk of developing skin cancer:
- Lighter natural skin color
- Family or personal history of skin cancer
- Excessive sun exposure
- Indoor tanning
- A history of sunburns, particularly early in life
- Skin that burns, freckles, or reddens easily, or becomes painful in the sun
- Blue or green eyes
- Blond or red hair
- Certain types of moles
If you are the type of person who always burns and never tans when in the sun, or if you burn easily, you are at increased risk for skin cancer.
Contrary to popular belief, a tan does not indicate good health.
It’s a sign of injury to skin cells by UV rays; the cells respond to this injury by producing more pigment.
