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Types of Skin Cancer
 Melanoma: Melanoma is a relatively common but virulent and serious cancer and was predicted by the American Cancer Society to occur in 62,480 Americans in 2008. Melanoma is highly curable when detected early, but can be an especially dangerous form of cancer if not detected early. It caused nearly 8,400 deaths in the U.S. in 2008.
Basal Cell Carcinoma: Basal cell carcinoma and squamous cell carcinoma are the most common cancers of the skin and account for 95 percent of non-melanoma skin cancer with basal cell carcinoma making up 75 percent of the skin cancers. More than one million cases of skin cancer are reported every year in the U.S. According to the National Cancer Institute, basal cell carcinoma accounts for the majority of non-melanoma skin cancers in the United States. It is a slow-growing cancer that seldom spreads to other parts of the body. It usually develops in parts of the body that are exposed to the sun, such as the head and neck. Basal cell carcinoma was once found mostly in middle-aged or older people. Now, however, it is also being seen in younger people.
Squamous Cell Carcinoma: Squamous cell carcinoma also rarely spreads, but it does so more often than basal cell carcinoma. This type of skin cancer usually appears on sun-exposed areas of the body, such as the face, ear, neck, lips, and backs of the hands. It can also begin within scars or skin ulcers elsewhere on the body. Less often, it can form in the skin of the genital area. Squamous cell carcinomas are more likely to invade tissues beneath the skin, and slightly more likely to spread to distant parts of the body than basal cell carcinomas. It is important that skin cancers be found and treated early because they can invade and destroy nearby tissue.
Causes and Prevention of Skin Cancer
Most skin cancers are caused by unprotected ultraviolet radiation exposure to the area of skin that develops the cancer. Most of this radiation comes from sunlight, but some may come from artificial sources, such as tanning booths. Exposure to the sun or tanning booths may have occurred a few years before the beginning of the cancer, particularly for squamous cell carcinoma. However, much of the exposure may have happened many years earlier. Children and young adults often receive intense sun exposure that may not result in an actual cancer for many years or decades.
Risk factors for developing skin cancer: Although anyone can develop skin cancer, the risk is greatest for people:
- With fair skin that freckles easily;
- People with marked freckling of the skin and those with excessive number of moles are at increased risk of developing melanoma;
- With naturally red or blond hair and blue or light-colored eyes;
- Living in areas that have high UV radiation from the sun, for example more so in Texas than Minnesota;
- Having had exposure to sun early in life and for melanoma, a history of three or more blistering sun burns in childhood and adolescence is considered a major risk factor of later development of melanoma;
- Melanoma may occur in areas of the body that are not exposed to the sun, which includes soles of the feet and sun-protected areas of the body such as inner lining of the nose, sinuses, mouth, anus and genital areas.
- Having a close relative, such as a parent or sibling, who has had skin cancer.
Prevention:
- Avoid exposure to the midday sun (from 10 a.m. to 2 p.m.).
- Wear protective closing, such as hats and long sleeves to block the sun’s harmful rays.
- Use sunscreen with an SPF factor of at least 15 or more on areas of skin exposed to the sun and reapply every one or two hours depending on your activity.
- Wear sunglasses with 99%-100% UV absorption to provide protection for the eyes and skin area around the eyes.
- Do not use tanning beds and sun lamp due the ultraviolet radiation they deliver.
Symptoms of skin cancer:
- The most common sign of skin cancer is a change on the skin, especially a new growth or a sore that does not heal.
- ot all skin cancer looks the same. For example, the cancer may start as a small, smooth, shiny, pale, or waxy lump. Or it can appear as a firm red lump. Sometimes, the lump bleeds or develops a crust. It can also start as a flat, red spot that is rough, dry or scaly.
- Melanoma most often appears as a black or brown pigmented lesion (or mole) with irregular borders and may be about the size of a pencil eraser.
- Basal and squamous cell cancers are found mainly on areas of the skin that are exposed to the sun—head, face, neck, hands, arm or upper back.
- Changes in skin are not sure signs of cancer, therefore see a doctor if any symptom lasts longer than two weeks.
- Skin cancer seldom hurts—so do not wait for an area to hurt.
Warning signs of melanoma:
Melanoma is by far the most serious of the skin cancers. Early diagnosis of melanoma allows treatment when it is easily treated and cured with a simple surgical removal of the cancer. Melanoma of the skin commonly presents as a pigmented lesion of the skin surface called a mole or a nevus. Early diagnosis is facilitated by using the ABCD guidelines on any suspicious pigmented lesion of the skin.
- Asymmetry - most early lesions grow at an uneven rate resulting in an asymmetric shape.
- Border irregularity - the uneven growth at the margin results in an irregular border with notches and dents.
- Color variegation - most melanomas have mixtures of colors with areas of light and dark brown or black pigment.
- Diameter - pigmented lesions with the ABC features and diameters greater than 6 mm (the size of a pencil eraser) should be considered suspicious for melanoma.
Most early melanomas have a flat surface that becomes thickened with increasing growth, ultimately resulting in formation of a nodule or an ulcer which tends to bleed easily.
Any pigmented lesion that shows a change in its color, size or shape or develops any symptoms of itching or bleeding should be examined by a physician and considered for a biopsy and microscopic examination to make a definite diagnosis.
More information on Melanoma.
Warning signs of basal cell carcinoma:
- Basal cell skin cancer often resembles non-cancerous skin conditions, such as psoriasis or eczema;
- An open sore that bleeds, oozes, or crusts and remain open for 3 or more weeks and persistently does not heal may be an early sign of basal cell carcinoma;
- A reddish patch or irritated area that may itch or hurt or not have any pain, frequently occurring on the chest, shoulders, arms, or legs;
- A shiny bump or nodule that is pearly or translucent and is often red, pink or white. The bump can also be tan, black or brown in dark-haired people.
- See a dermatologist if suspicious about any unusual growth on the skin.
Warning signs of squamous cell carcinoma:
- A wart-like growth that crusts and occasionally bleeds;
- A persistent, scaly red patch with irregular borders that sometimes crusts and bleeds;
- An open sore that bleeds and scabs over and persists for weeks.
Diagnosis and treatment options for skin cancer (non-melanoma):
Basal cell carcinoma and squamous cell carcinoma (non-melanomas) are generally diagnosed and treated in the same way. When an area of skin does not look normal, the doctor may remove all or part of the growth. The dermatologist may remove the lesions in one of several most common methods depending on the type of skin cancer and the location:
- Freezing or Cryosurgery – is involves removing cancerous cells by freezing them with liquid nitrogen (cryosurgery). This is used for small squamous cell carcinomas, but is not recommended for larger tumors or those on certain areas of the face.
- Surgical excision – Many skin cancers can be cut or excised from the skin quickly and easily. The dermatologist or plastic surgeon may cut out the squamous cell carcinoma and the surrounding margin of healthy sin. The cancer is sometimes completely removed at the time of the biopsy and no further treatment is needed. Always consult with the dermatologist or plastic surgeon if the lesion is on the eye, eyelid, nose, ears, or other area of the body to make sure there will be minimal scarring.
- Mohs’ surgery – The dermatologist or plastic surgeon trained and certified in Mohs’ surgery removes the tumor layer by layer and examines each layer of skin under the microscope until no abnormal cells remain. This allows the entire growth to be removed without taking an excessive amount of surrounding healthy skin. Mohs’ surgery should only be performed by physicians specifically trained in the procedure.
- Other less often used methods – There are prescription creams and lotions that may be used directly on the skin as an anti-cancer agent, and they may cause inflammation so discuss with your dermatologist. In some cases, radiation therapy or radiotherapy may be used for (1) cancers of the eyelid, tip o f the nose or ear or for (2) very large and deep tumors. The radiation uses high-energy rays to damage cancer cells and stop them from growing. Discuss with your physician.
Suggested sources for more information:
American Cancer Society www.cancer.org
National Cancer Institute www.cancer.gov
Updated: 4-1-09
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