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What is skin cancer?

Skin cancer is the uncontrolled growth of abnormal skin cells, most often caused by damage from ultraviolet (UV) radiation from the sun, tanning beds or sunlamps.

The three main types of skin cancer are basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and melanoma.

BCC and SCC are considered nonmelanoma skin cancers and are sometimes referred to as keratinocyte carcinomas. Melanoma, though less common, is the most serious and potentially deadly form.

In the United States, about 3 million cases of nonmelanoma skin cancer are diagnosed each year. In 2025, it’s estimated that 212,200 patients will be diagnosed with a form of melanoma.


An adult applies sunscreen to the face of a child on the beach.Sun safety: common misconceptions

“There are several common misconceptions people have about sun safety and skin cancer,” says Laura Ferris, MD, MPH, chair of the department of dermatology and the Clayton E. Wheeler, Jr. Distinguished Professor at UNC School of Medicine and UNC Health. “For example, many believe that getting a base tan will prevent burning on vacation — when really there’s no such thing as safe tan — or that sunscreen only needs to be applied once a day,” Ferris said.

Reminder: Sunscreen should be applied every two hours or sooner if you’ve been in water because it can wash off.

Common myths around sun safety

Myth: SPF 15 is always enough

“Studies show that because most people don’t apply enough sunscreen, they get better protection from higher SPFs,” Ferris said.

When picking a sunscreen, aim for a minimum of SPF 30 and pick one with ingredients that are generally recognized as safe and effective (GRASE) by the FDA.

For a complete guide, check out this UNC Health Talk article: Everything You Need to Know About Sunscreen.


Myth: Not everywhere needs protection

Parts of the body, including behind the ears, bottoms of the feet and the scalp are often-overlooked areas when it comes to sun protection.

“The scalp is a big one for skin cancer,” Ferris said. “Hats, sunglasses and protective clothing are all very important.”


Myth: If I’m driving or it’s cloudy, I don’t need to apply sunscreen or protect my skin

While car windows block a percentage of UV rays (particularly UVB), they don’t offer complete protection.

If you’re spending most of the day in your car, you still need to practice sun safety to prevent cellular damage. The same holds true for cloudy days or colder weather. Skin protection is important every day, year-round.


Skin cancer risk factors

While any individual — regardless of skin tone, location or family history — can develop skin cancer, certain factors may increase your risk.

History of sunburns and tanning bed use

Whether it’s a few severe sunburns or frequent use of tanning beds, excessive and repeated UV exposure can significantly increase your chances of developing skin cancer down the line.


Geographical location

Living closer to the equator or at higher altitudes increases UV radiation exposure. For example, midday sun in Miami, even on a cloudy day, is stronger than midday sun in Boston. However, proper protection is necessary in both locations.


Fair skin and lighter features

While skin cancer affects all skin tones, very fair skin that burns or freckles easily, or lighter features like blue or green eyes or red or blonde hair, raises the chance of harm from UV rays. That’s because less melanin — the natural pigment protecting skin cells from UV radiation — means less defense. Still, protection is needed for everyone, regardless of complexion.


Family or personal history

Skin cancer can run in families and increase your risk because of inherited genes. Also, if you’ve had skin cancer before, you’re more likely to get it again.


Age

“As we get older, the risk of skin cancer increases,” Ferris explained. “While skin cancer is rare in children, the sun exposure they accumulate throughout their lives contributes to their later risk. For children and young adults, the focus should be on consistent sun protection to prevent excessive UV exposure. For older adults, ongoing sun safety and skin awareness are both key.”


When to see a doctor

Skin cancer spots aren’t always easy to notice, so be sure to check your skin often for new marks or changes.

Schedule an appointment with a dermatologist if you notice one or more of the following:

  • A mark that matches the ABCDEs of melanoma: asymmetrical shape, irregular borders, uneven color, a diameter larger than a pencil eraser or one that is evolving
  • A lesion that looks different from the rest of the spots on your body — often called the “ugly duckling sign”
  • Pink or red bumps that appear and don’t go away or continue growing

A dermatologist can evaluate suspicious spots and may perform a biopsy to determine if cancer is present.

To speak with a specialist or schedule a skin consult, head to UNC Health’s Find a Doctor portal to search for nearby dermatologists.