Three types of skin cancer account for nearly 100% of all diagnosed cases.
The different types of skin cancer are:
Basal Cell Carcinoma The most common cancer in humans, BCC develops in more than 1 million people every year in the United States alone. About 80% of all skin cancers are BCC, a cancer that develops in the basal cells (skin cells found in the lower part of the epidermis). Most BCCs appear on skin with a history of exposure to the sun, such as the face, ears, scalp, and upper trunk. The major risk factors for developing BCC are excessive and chronic sun exposure and fair skin. These tumors tend to grow slowly and very rarely metastasize. However, if left untreated, they may become large and disfiguring. Early, effective treatment of basal cell carcinoma has a cure rate of more than 95%. However, new basal cell carcinomas can develop after treatment, so continued self-examination and regular examination by a dermatologist are important.
Squamous Cell Carcinoma Squamous cell carcinoma is the second most common skin cancer. This cancer begins in the squamous cells (skin cells found in the upper layer of the epidermis). Unlike basal cell carcinoma, this form of cancer can metastasize (spread to other parts of the body); therefore, it is important to get early treatment. The major risk factors for developing squamous cell carcinoma include excessive, chronic exposure to sun, chronic exposure to x-rays, long-term treatment with immunosuppressive drugs and white skin. While most commonly found on sun-exposed areas of the body, it can develop anywhere, including the inside of the mouth and the genitalia. When found early and treated properly, the cure rate for squamous cell carcinomas is over 95 percent.
Melanoma Accounting for about 4% of all diagnosed skin cancers, melanoma begins in the melanocytes (cells that give skin its color).Melanoma has been coined “the most lethal form of skin cancer” because it can rapidly spread. With early detection and proper treatment, the cure rate for melanoma is about 95%. Once its spreads, the prognosis is poor. Melanoma may appear suddenly or begin in or near a mole. Excessive sun exposure, especially sunburn, is the most important preventable cause of melanoma. Light-skinned individuals are at particular risk. Heredity also plays a role, as an individual has an increased chance of developing melanoma if a relative has had melanoma. Atypical moles, which may run in families, and a large number of moles, can serve as markers for people at increased risk for developing melanoma. To detect skin cancer in its early and most treatable stage, everyone should perform regular self- examinations of their skin. Today, more than half of all diagnosed melanomas are first identified by the patient.
A-B-C-D Criteria Self-examination is done using the A-B-C-D criteria:
A=Asymmetry (the left side of the lesion is unlike the right side)
B=Border Irregularity (the lesion has a scalloped or poorly defined border)
C=Color Variation (not all parts of the lesion are the same color; within the lesion may be patches of tan, brown, black, pink, white or blue)
D=Diameter (while melanomas are usually greater than 6mm in diameter when diagnosed, they can be smaller. If you notice a mole different from others, or which changes, itches or bleeds even if it is smaller than 6mm, you should see a dermatologist)
Some melanomas do not conform to the A-B-C-D criteria, so any suspicious mole should be examined by a dermatologist. Any mole that appears different from others, or which changes, itches, or bleeds even if it is smaller than 6 millimeters, should be seen by a dermatologist.
Sun Protection Practices
Sun protection can significantly decrease a person’s risk of developing skin cancer. Sun protection practices include:
Avoidance. The most effective preventive method is sun avoidance. Seek shade between the hours of 10:00am to 4:00pm. Avoid deliberate tanning. Tanning beds and sunlamps are just as dangerous because they, too, emit enough UV radiation to cause premature aging and skin cancer.
Generously apply a water-resistant sunscreen with a Sun Protection Factor (SPF) of at least 15 year-round to all exposed skin that provides broad-spectrum protection from both ultraviolet A (UVA) and ultraviolet B (UVB) rays to all exposed skin. Re-apply every two hours, even on cloudy days, and after swimming or sweating.
Wear protective clothing, such as a long-sleeved shirt, pants, a wide-brimmed hat, and sunglasses, where possible. Use extra caution near water, snow, and sand as they reflect the damaging rays of the sun. This can increase your risk chance of sunburn.