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What is skin cancer?
Skin cancer is a malignant tumor that grows in the skin cells and accounts for more than 50 percent of all cancers. In the US alone, more than 1 million Americans will be diagnosed in 2008 with nonmelanoma skin cancer, and 62,480 will be diagnosed with melanoma, according to the American Cancer Society.
What are the different types of skin cancer?The following chart is provided solely for informational purposes; you must consult a trained professional for diagnosis and treatment. There are three main types of skin cancer, including:
|basal cell carcinoma
|Basal cell carcinoma accounts for approximately 75 percent of all skin cancers. This highly treatable cancer starts in the basal cell layer of the epidermis (the top layer of skin) and grows very slowly. Basal cell carcinoma usually appears as a small, shiny bump or nodule on the skin - mainly those areas exposed to the sun, such as the head, neck, arms, hands, and face. It commonly occurs among persons with light-colored eyes, hair, and complexion.
|squamous cell carcinoma
|Squamous cell carcinoma, although more aggressive than basal cell carcinoma, is highly treatable. It accounts for about 20 percent of all skin cancers. Squamous cell carcinoma may appear as nodules or red, scaly patches of skin, and may be found on the face, ears, lips, and mouth. However, squamous cell carcinoma can spread to other parts of the body. This type of skin cancer is usually found in fair-skinned people.
|Malignant melanoma accounts for 3 percent of all skin cancers, and accounts for 75 percent of deaths from skin cancer. Malignant melanoma starts in the melanocytes - cells that produce pigment in the skin. Malignant melanomas usually begin as a mole that then turns cancerous. This cancer may spread quickly. Malignant melanoma most often appears on fair-skinned men and women, but persons with all skin types may be affected.
Distinguishing benign moles from melanoma:
To prevent melanoma, it is important to examine your skin on a regular basis, and become familiar with moles, and other skin conditions, in order to better identify changes. According to recent research, certain moles are at higher risk for changing into malignant melanoma. Moles that are present at birth, and atypical moles, have a greater chance of becoming malignant. Recognizing changes in moles, by following this ABCD Chart, is crucial in detecting malignant melanoma at its earliest stage. The following chart is provided solely for informational purposes; you must consult a trained professional for diagnosis and treatment. The warning signs are:
|Normal Mole / Melanoma
|when half of the mole does not match the other half
|when the border (edges) of the mole are ragged or irregular
|when the color of the mole varies throughout
|if the mole's diameter is larger than a pencil's eraser
Melanomas vary greatly in appearance. Some melanomas may show all of the ABCD characteristics, while other may only show changes in one or two characteristics. Always consult your physician for a diagnosis.
What are the risk factors for melanoma?
Skin cancer is more common in fair-skinned people - especially those with blond or red hair, who have light-colored eyes. Skin cancer is rare in children. However, no one is safe from skin cancer. Almost half of all Americans who live to age 65 will be diagnosed with skin cancer at some point in their lives, according to the National Cancer Institute. Other risk factors include the following:
Prevention of skin cancer:
The American Academy of Dermatology (AAD) has declared war on skin cancer by recommending these three preventive steps:
Wear protective clothing, including a hat with a four-inch brim.
Apply sunscreen all over your body and avoid the midday sun from 10 a.m. to 4 p.m.
Regularly use a broad-spectrum sunscreen with an SPF of 15 or higher, even on cloudy days.
The following six steps have been recommended by the AAD and the Skin Cancer Foundation to help reduce the risk of sunburn and skin cancer.
The American Academy of Pediatrics (AAP) approves of the use of sunscreen on infants younger than 6 months old if adequate clothing and shade are not available. Parents should still try to avoid sun exposure and dress the infant in lightweight clothing that covers most surface areas of skin. However, parents also may apply a minimal amount of sunscreen to the infant's face and back of the hands.
Remember, sand and pavement reflect UV rays even under the umbrella. Snow is also a particularly good reflector of UV rays. Reflective surfaces can reflect up to 85 percent of the damaging sun rays.
How to perform a skin self-examination:
Finding suspicious moles or skin cancer early is the key to treating skin cancer successfully. A skin self-examination is usually the first step in detecting skin cancer. The following suggested method of self-examination comes from the American Cancer Society:
(You will need a full-length mirror, a hand mirror, and a brightly lit room.)
Examine your body front and back in mirror, then the right and left sides, with your arms raised.
*family history of melanomasun exposure
*The amount of time spent unprotected in the sun directly affects your risk of skin cancer.
*early childhood sunburns
*Research has shown that sunburns early in life increase a person's risk for skin cancer later in life.
*many ordinary moles (more than 50)
Basal Cell Carcinoma
The most frequent form of skin cancers
BCCs are abnormal, uncontrolled growths or lesions that arise in the skin’s basal cells, which line the deepest layer of the epidermis (the outermost layer of the skin). BCCs often look like open sores, red patches, pink growths, shiny bumps, or scars. Usually caused by a combination of cumulative UV exposure and intense, occasional UV exposure, BCC can be highly disfiguring if allowed to grow, but almost never spreads (metastasizes) beyond the original tumor site. Only in exceedingly rare cases can BCC spread to other parts of the body and become life-threatening.
There are an estimated 2.8 million cases of BCC diagnosed in the US each year. In fact, it is the most frequently occurring form of all cancers. More than one out of every three new cancers are skin cancers, and the vast majority are BCCs. It shouldn’t be taken lightly: this skin cancer can be disfiguring if not treated promptly. Are you at risk? We have the information you need about the prevention, detection, and treatment of basal cell carcinoma.
Squamous Cell Carcinoma
The second most frequent form of skin cancer
Squamous cell carcinoma (SCC) is an uncontrolled growth of abnormal cells arising in the squamous cells, which compose most of the skin’s upper layers (the epidermis). SCCs often look like scaly red patches, open sores, elevated growths with a central depression, or warts; they may crust or bleed. SCC is mainly caused by cumulative UV exposure over the course of a lifetime. It can become disfiguring and sometimes deadly if allowed to grow. An estimated 700,000 cases of SCC are diagnosed each year in the US, resulting in approximately 2,500 deaths.
SCCs may occur on all areas of the body including the mucous membranes and genitals, but are most common in areas frequently exposed to the sun, such as the rim of the ear, lower lip, face, bald scalp, neck, hands, arms and legs. Often the skin in these areas reveals telltale signs of sun damage, such as wrinkling, changes in pigmentation, and loss of elasticity.
The most dangerous form of skin cancer
The most dangerous form of skin cancer, these cancerous growths develop when unrepaired DNA damage to skin cells (most often caused by ultraviolet radiation from sunshine or tanning beds) triggers mutations (genetic defects) that lead the skin cells to multiply rapidly and form malignant tumors. These tumors originate in the pigment-producing melanocytes in the basal layer of the epidermis. Melanomas often resemble moles; some develop from moles. The majority of melanomas are black or brown, but they can also be skin-colored, pink, red, purple, blue or white. Melanoma is caused mainly by intense, occasional UV exposure (frequently leading to sunburn), especially in those who are genetically predisposed to the disease. Melanoma kills an estimated 8,790 people in the US annually.
If melanoma is recognized and treated early, it is almost always curable, but if it is not, the cancer can advance and spread to other parts of the body, where it becomes hard to treat and can be fatal. While it is not the most common of the skin cancers, it causes the most deaths. The American Cancer Society estimates that at present, about 120,000 new cases of melanoma in the US are diagnosed in a year. In 2010, about 68,130 of these were invasive melanomas, with about 38,870 in males and 29,260 in women. In most cases, the surgery for thin melanomas can be done in the doctor’s office or as an outpatient procedure under local anesthesia. Stitches (sutures) remain in place for one to two weeks, and most patients are advised to avoid heavy exercise during this time. Scars are usually small and improve over time.
Discolorations and areas that are depressed or raised following the surgery can be concealed with cosmetics specially formulated to provide camouflage. If the melanoma is larger and requires more extensive surgery, a better cosmetic appearance can be obtained with flaps made from skin near the tumor, or with grafts of skin taken from another part of the body. For grafting, the skin is removed from areas that are normally or easily covered with clothing.
There is now a trend towards performing sentinel node biopsy and tumor removal surgery at the same time, provided the tumor is 1 mm or more thick. When the procedures are combined in this way, the patient is spared an extra visit.
In the new approach to surgery, much less of the normal skin around the tumor is removed and the margins, therefore, are much narrower than they ever were before. This spares significant amounts of tissue and reduces the need for postoperative cosmetic reconstructive surgery.
Most US surgeons today follow the guidelines recommended by the National Institutes of Health and the American Academy ofDermatology Task Force on Cutaneous Melanoma.
These margins all fall within the range of what is called “narrow” excision. When you consider that until recently, margins of 3 to 5 cm (wide excision) were standard, even for comparatively thin tumors, you can see how dramatically surgery has changed for the better. Physicians now know that even when melanomas have reached a thickness of 4 mm or more, increasing the margins beyond 2 cm does not increase survival.
Dysplastic nevi (atypical moles) are unusual benign moles that may resemble melanoma. People who have them are at increased risk of developing single or multiple melanomas. The higher the number of these moles someone has, the higher the risk; those who have 10 or more have 12 times the risk of developing melanoma compared to the general population. Dysplastic nevi are found significantly more often in melanoma patients than in the general population.
Medical reports indicate that about 2 to 8 percent of the Caucasian population have these moles. Heredity appears to play a part in their formation. Those who have dysplastic nevi plus a family history of melanoma (two or more close blood relatives with the disease) have an extremely high risk of developing melanoma. Individuals who have dysplastic nevi, but no family history of melanoma, still face a 7 to 27 times higher risk of developing melanoma compared to the general population—certainly a great enough risk to warrant monthly self-examination, regular professional skin exams and daily sun protection.
The Most Common Pre-skin cancer lesion
Scaly or crusty growths (lesions) caused by damage from the sun’s ultraviolet (UV) rays, actinic keratosis (AK) is also known as solar keratoses. They typically appear on sun-exposed areas such as the face, bald scalp, lips, and the back of the hands, and are often elevated, rough in texture, and resemble warts. Most become red, but some will be tan, pink, red, and/or flesh-toned. Untreated AKs can advance to squamous cell carcinoma (SCC), the second most common form of skin cancer, and some experts believe they are actually the earliest stage of SCC.
It affects more than 58 million Americans. This figure is generally accepted as the best current estimate of the number of Americans with actinic keratosis (AK). People with a fair complexion, blond or red hair, and blue, green or grey eyes (Identify Your Skin Type) have a high likelihood of developing one or more of these common precancers if they spend time in the sun and live long enough. Location makes a difference: The closer to the equator you live, the more likely you are to have actinic keratoses. The incidence is slightly higher in men, because they tend to spend more time in the sun and use less sun protection than women do. African-Americans, Hispanics, Asians and others with darker skin are not as susceptible as Caucasians (Skin Cancer and Skin of Color).Treatment options for actinic keratosis are numerous.
Medicated creams and solutions are very effective by themselves or in combination with another form of treatment when a person has many actinic keratoses.
5-fluorouracil (5-FU) ointment or liquid in concentrations from 0.5 to 5 percent has FDA approval and is the most widely used topical treatment for actinic keratoses. It is effective against not only the surface lesions but also the subclinical ones. Rubbed gently onto the lesions once or twice a day for two to four weeks, it produces cure rates of up to 93 percent. Reddening, swelling and crusting may occur, but they are temporary. The lesions usually heal within two weeks of stopping treatment. There is rarely scarring and the cosmetic result is good.
Imiquimod 5% cream, also FDA-approved, works in a different way: It stimulates the immune system to produce interferon, a chemical that destroys cancerous and precancerous cells. It is rubbed gently on the lesion twice a week for four to sixteen weeks. The cream is generally well-tolerated, but some individuals develop redness and ulcerations.
This is the most commonly used treatment method when a limited number of lesions exist. No cutting or anesthesia is required. Liquid nitrogen, applied with a spray device or cotton-tipped applicator, freezes the growths. The lesions subsequently shrink or become crusted and fall off. Temporary redness and swelling may occur after treatment, and in some patients, white spots may remain permanently.
If one form of therapy is good, two may be better; some of the treatment options described here are especially effective when used together or in sequence. This approach can both improve the cure rate and reduce side effects. One to two weeks of 5-FU followed by cryosurgery can reduce the healing time for 5-FU and decrease the likelihood of white spots following cryosurgery.
This method, best known for reversing the signs of photoaging, is also used to remove some actinic keratoses on the face. Trichloroacetic acid (TCA) and/or similar chemicals are applied directly to the skin. The top skin layers slough off and are usually replaced within seven days. This technique requires local anesthesia and can cause temporary discoloration and irritation.