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skin health center/skin a-z list/skin cancer overview center /skin cancer overview article
What is skin cancer?
Most skin cancers are locally destructive cancerous (malignant) growth of the skin. They originate from the cells of the epidermis, the superficial layer of the skin. Unlike cutaneous malignant melanoma, the vast majority of these sorts of skin cancers rarely spread to other parts of the body (metastasize) and become life-threatening.
There are three major types of skin cancer: (1) basal cell carcinoma (the most common), (2) squamous cell carcinoma (the second most common), which originate from skin cells, and (3) melanoma, which originates from the pigment-producing skin cells (melanocytes) but is less common, though more dangerous, than the first two varieties. Other rare forms of skin cancer include lymphomas, Merkel cell cancers, and cancers of other tissue in the skin, including sarcomas as well as hair and sweat gland tumors. In this article, we will only be reviewing the most common forms of cancers, basal cell carcinoma and squamous cell carcinoma.
BCC is the most common type of skin cancer and has a predilection for sun-exposed skin. Tumors may appear as a pearly or waxy bumps usually with visible blood vessels (nodular BCC), or as a flat scaly reddish patch (superficial BCC) with a brown border, or as a hard or scar-like lesion (sclerosing BCC). Frequently BCCs can be itchy, often bleed, or in more advanced cases, ulcerate.
What are the risk factors for skin cancer?
The most common risk factors for skin cancer are as follows.
Is skin cancer hereditary?
Since most skin cancers are caused by ultraviolet light exposure, skin cancers are generally not considered to be inherited. But the fact that skin cancer is much more common among poorly pigmented individuals and that skin color is inherited does support the proposition that genetics is very important. There are some very rare genetic syndromes that result in an increased number of skin cancers in those affected.
What causes skin cancer?
Except in rare instances, most skin cancers arise from DNA mutations induced by ultraviolet light affecting cells of the epidermis. Many of these early cancers seem to be controlled by natural immune surveillance, which when compromised, may permit the development of masses of malignant cells that begin to grow into tumors.
What are the different types of skin cancer?
What are the signs and symptoms of skin cancer?
Most basal cell carcinomas have few if any symptoms. Squamous cell carcinomas may be painful. Both forms of skin cancer may appear as a sore that bleeds, oozes, crusts, or otherwise will not heal. They begin as a slowly growing bump on the skin that may bleed after minor trauma. Both kinds of skin cancers may have raised edges and central ulceration.
Signs and symptoms of basal cell carcinomas include:
Signs and symptoms of squamous cell carcinomas include:
Actinic keratoses (AK), also called solar keratoses, are scaly, crusty lesions caused by damage from ultraviolet light, often in the facial area, scalp, and backs of the hands. These are considered precancers because if untreated, up to 10% of actinic keratoses may develop into squamous cell carcinomas.
When is a mole dangerous or high risk for becoming a skin cancer?
Moles are almost always harmless and only very rarely turn into skin cancer. If a mole becomes cancerous, it would be a melanoma. There is a precancerous stage, called a dysplastic nevus, which is somewhat more irregular than a normal mole. An early sign of melanoma is noticing a difference in a mole: asymmetry, irregular border, color changes, increasing diameter, or other evolving changes may signify a mole is a melanoma. Moles never become squamous cell carcinomas or basal cell carcinomas.
What are the most common sites where skin cancer develops?
Skin cancers typically arise in areas of the skin exposed to the sun repeatedly over many years such as on the face and nose, ears, back of the neck, and the bald area of the scalp. Less commonly, these tumors may appear at sites with only limited sun exposure such as the back, chest, or the extremities. However, skin cancer may occur anywhere on the skin.
How do physicians diagnose skin cancer?
A skin examination by a dermatologist is the way to get a definitive diagnosis of skin cancer. In many cases, the appearance alone is sufficient to make the diagnosis.
A skin biopsy is usually used to confirm a suspicion of skin cancer. This is performed by numbing the area under the tumor with a local anesthetic such as lidocaine. A small portion of the tumor is sliced away and sent for examination by a pathologist, who looks at the tissue under a microscope and renders a diagnosis based on the characteristics of the tumor.
What is the staging for skin cancer?
There is no specific staging system for basal cell carcinoma. If the tumor is wider than 2 cm (about ¾ inch diameter), it is probably a more serious tumor. Basal cell carcinomas of the ears, nose, and eyelid may also be of more concern, regardless of the size.
There is a staging system for squamous cell carcinoma. Large tumors that are thicker than 2 mm, invade the nerve structures of the skin, occur on the ear, and have certain worrisome characteristics under the microscope are of more concern. If the tumor metastasizes to a site at some distance from the primary tumor, the cancer is likely to be a dangerous tumor.
What is the treatment for skin cancer?
There are several effective means of treating skin cancer. The choice of therapy depends on the location and size of the tumor, the microscopic characteristics of the cancer, and the general health of the patient.
What kinds of doctors treat skin cancer?
The main type of doctor who will treat skin cancer is a dermatologist. Your primary care physician or internist may first notice a sign of skin cancer but will refer you to a dermatologist for further testing and treatment. You may also see an oncologist, which is a cancer specialist.
If you have surgical removal of a tumor, depending on how much skin is removed, you may see plastic or reconstructive surgeon after the tumor removal to help restore the appearance of the skin, especially on the face.
What is the prognosis and survival rate for skin cancer?
The prognosis for nonmelanoma skin cancer is generally excellent. Both basal cell carcinoma and squamous cell carcinoma are highly curable. There are virtually no deaths from basal cell carcinoma and only rare deaths with squamous cell carcinoma skin cancers, mostly in immunosuppressed individuals. Depending on the method of treatment and the location and type of skin cancer, the likelihood of a recurrence of a previously treated skin cancer is as low as 1% to 2% for Mohs surgery and up to 10% to 15% for destruction by electrodesiccation and curettage.
Early detection of skin cancers can lead to better outcomes. Know your skin and if you have any moles or spots that are suspect, see a dermatologist for a skin cancer screening. Awareness is key in identifying and treating skin cancers early.
Is it possible to prevent skin cancer?
Many skin cancers can be prevented by avoiding triggers that cause tumors to develop. Prevention strategies include protection from the sun by the use of sunscreens, protective clothing, and avoidance of the sun during the peak hours of 9 a.m. to 3 p.m. Parents should ensure children are protected from the sun. Do not use tanning beds, which are a major cause of excess ultraviolet light exposure and a significant risk factor for skin cancer. The American Academy of Dermatology (AAD) has noted a dramatic rise in the numbers and cost of skin cancer. Furthermore, there has been an increase in the total number of skin cancers and that new breakthrough treatments for melanoma, although expensive, comprise only a small portion of the total cost of skin cancer treatment. Most skin cancers are treated cost efficiently by dermatologists in an office setting.
Sunscreen use and vitamin D
A major source of vitamin D comes from sunlight exposure, which leads to the production of the vitamin in the skin. Some argue sunscreens block out so much of the sun's rays that inadequate vitamin D synthesis results. In fact, very few people actually apply sunscreen to every inch of their exposed skin, so vitamin D synthesis does occur. There is no reason not to use sunscreens because of a fear of low vitamin D. If there is a concern, vitamin D can be obtained by eating leafy vegetables or taking an oral multivitamin supplement.
Genital warts is a sexually transmitted infection (STI, STD) caused by the human papillomavirus (HPV). It is the most common STD in the US. The warts can appear anywhere on the skin where sexual contact has occurred.
The warts look like raised, flesh-colored lumps or bumps that have a cauliflower-like appearance. Signs and symptoms of genital warts in women include vaginal, vulva, or groin pain, itching, and burning where the wart(s) is.
Treatment can remove warts or lesions, but it does not prevent spread of the virus, and the warts usually grow back. Removing genital warts does not prevent the infection from spreading elsewhere on the body.
There is no cure for genital warts, and there is no vaccine to prevent them; however, there is a vaccine to prevent infection from four common types of HPV. Gardasil vaccine available for female adolescents and teens to prevent HPV infection and cervical cancer.
In the nature vs. nurture debate, “nature” represents our genetic makeup. These are the genes you have inherited from your biological family, and that may affect your physical and mental health, for example, intelligence, disease, and psychological health. While “nurture” represents how our environment affects our intelligence, traits, personality, and mental and physical health. Studies have shown that a person’s environment can alter his or her genes, and lower their risk of developing certain inherited diseases, conditions, and mental illnesses that run in his or her family.
Researchers and doctors have found that particular physical traits like eye and skin color, and diseases like Huntington’s chorea are the result of genetic inheritance (inherited from a family member). However, patterns of thinking and behavior can be attributed to both nature and nurture (your genes and your environment). Moreover, researchers who study the brain have found overwhelming evidence that a person’s genetic factors and his or her experiences guide and support brain development. The human brain produces new nerve cells (neurons) into adulthood, and these nerve cells can change the strength of their connections throughout life, which can affect intelligence and other factors.