What is skin cancer and why is it a concern?

Skin cancer is the uncontrolled growth of abnormal skin cells. While healthy cells grow and divide in an orderly way, cancer cells grow and divide in a rapid, disorganized manner. This rapid growth results in tumors, which are either benign (non-cancerous) or malignant (cancerous).

There are three main types of skin cancer: basal cell carcinoma, squamous cell carcinoma, and melanoma. Basal cell cancer and squamous cell cancers, also referred to as non-melanoma skin cancer, are the most frequently observed types of skin cancer. Between 40 to 50 % of Americans who live to age 65 will develop either basal cell or a squamous cell cancer at least once. Non-melanoma skin cancers are highly curable when treated early.

Melanoma, made up of pigment cells called melanocytes, is the most dangerous form of skin cancer, and causes most of all skin cancer deaths. Left untreated or caught at an advanced stage, it can spread to other organs, where it becomes difficult to treat.

Skin cancer is the most prevalent form of all cancers in the United States. It is estimated that one in five Americans will develop skin cancer in the course of a lifetime. Fortunately, skin cancer almost always can be cured when detected and treated early. Seeking medical attention at the first suspicion of skin cancer is critical to successful treatment.

What causes skin cancer?

Ultraviolet (UV) radiation is a proven human cancer-causing agent and is the number one cause of skin cancer. UV light from tanning beds is just as harmful. Exposure to sunlight during the winter months puts you at the same risk as exposure during the summer time. One blistering sunburn in childhood increases by double the chances of developing melanoma later in life. One indoor UV tanning session increases users’ risk of developing squamous cell carcinoma by 67 percent and basal cell carcinoma by 29 percent.

Other less common causes of skin cancer include X-ray exposure, scars from burns or disease, and occupational exposure to certain chemicals.

Who is at risk?

Although anyone can get skin cancer, the risk is greatest for people who have fair or freckled skin that burns easily, light eyes, and blond or red hair. Darker-skinned individuals are also susceptible to skin cancer, although their risk is substantially lower. Other risk factors include family history or personal history of skin cancer. Those with outdoor jobs or those who live in sunny climates are at increased risk. Organ transplant patients are up to 250 times more likely to develop squamous cell carcinoma skin cancer (SCC) when compared to the general population.

Risk factors unique to melanoma include a history of severe sunburns and an abundance of large and irregular moles.

What are the signs and symptoms?

The most common warning sign of skin cancer is a change on the skin, typically a new growth, or a change in an existing growth or mole.

  • Basal cell carcinoma might appear as a small, smooth, pearly or waxy bump on the face, ears, and neck; or as a flat, pink/red- or brown-colored lesion on the trunk or arms and legs.
  • Squamous cell carcinoma can appear as a firm, red nodule, or as a rough, scaly flat lesion that might itch, bleed, and become crusty. Both basal cell and squamous cell cancers mainly occur on areas of the skin frequently exposed to the sun, but can occur anywhere.
  • Melanoma usually appears as a pigmented patch or bump. It might resemble a normal mole, but usually has a more irregular appearance. Thinking of the ABCD rule tells you what signs to watch for:
    • Asymmetry—The shape of one half doesn't match the other.
    • Border—The edges are ragged or blurred.
    • Color—Uneven shades of brown, black, tan, red, white, or blue might be present.
    • Diameter—A change in size occurs (greater than 6 mm).

Be alert to pre-cancerous skin lesions that can develop into non-melanoma skin cancer. They appear as small scaly, tan or red spots, and are most often found on surfaces of the skin chronically exposed to the sun, such as the face and backs of the hands.

How is skin cancer diagnosed and treated?

Skin cancer is diagnosed by performing a biopsy. This is the removal of a sample of tissue that is then placed under a microscope and examined by a pathologist. Sometimes, a biopsy can remove all the cancer tissue and no further treatment is needed.

Treatment of skin cancer depends on the type and extent of the disease. However, surgery is frequently used to treat many skin cancers, and it is standard treatment for melanoma.

Mohs surgery is a technique used to treat certain non-melanoma skin cancers, and is considered the single most effective technique for treating certain non-melanoma skin cancers. This technique allows sparing the greatest amount of healthy tissue while effectively removing cancer cells. It should be performed only by a dermatologic surgeon who is specially trained in Mohs surgery. Other treatments include cryosurgery (freezing), drugs (including chemotherapy and biological response modifiers), laser therapy, radiation therapy, and clinical trials involving new treatment methods.

Skin cancer treatment often can involve more than one type of medical specialty. The specialties of dermatology, plastic surgery, medical oncology, pathology, and/or radiation oncology might be combined. For this reason, finding a medical center with a multi-disciplinary team approach to diagnosing and treating skin cancer is important. In a multi-disciplinary environment, team members consult, discuss, and agree upon the diagnosis. Together, they determine the most appropriate treatment for each skin cancer patient.

How can I prevent skin cancer?

With so many activities taking place outdoors, avoiding the sun is often not feasible or desirable. Practicing sensible sun exposure behavior is your best defense against skin cancer.

Physicians and professional medical organizations such as the American Academy of Dermatology (AAD), the National Cancer Institute (NCI), and the Centers for Disease Control and Prevention (CDC) recommend the following precautions:

  • Apply sunscreen with a sun protection factor (SPF) of 15 or greater 30 minutes before sun exposure and every few hours thereafter.
  • Wear sunglasses with total UV protection.
  • Wear protective clothing and hats.
  • Avoid direct sun exposure as much as possible during peak UV radiation hours between 10:30 a.m. and 3:30 p.m.
  • Perform skin self-exams regularly to become familiar with existing growths and to notice any changes or new growths.
  • As a parent, be a good role model and foster skin cancer prevention habits in your children.

Stopping skin cancer starts with awareness

With the incidence of skin cancer at an all time high, the immediate goal of doctors is to successfully treat people with skin cancer. The long-term goal is to drastically reduce future cases of skin cancer. To reach this goal, physicians, health care providers, and professional organizations aggressively promote public awareness about the dangers of skin cancer. They provide education on ways to help prevent it. Only through awareness can we change our behavior to incorporate skin cancer prevention into our daily lives.

Index Value*

  • 0-2
    • Exposure Level: Minimal
    • Minutes to Burn Without Protection: 60 Minutes
  • 3-4
    • Exposure Level: Low
    • Minutes to Burn Without Protection: 45 Minutes
  • 5-6
    • Exposure Level: Moderate
    • Minutes to Burn Without Protection: 30 Minutes
  • 7-10
    • Exposure Level: High
    • Minutes to Burn Without Protection: 15 Minutes
  • 10+
    • Exposure Level: Very High
    • Minutes to Burn Without Protection: 10 Minutes

*Knowing each day’s UV Index level and preparing against it—sunscreen with SPF 15 or more, sunglasses with UV protection, and protective clothing and hats—will significantly reduce your risk of developing skin cancer.

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