Skin cancer is the uncontrollable growth of abnormal cells in the outermost skin layer. This occurs when damage to cell DNA goes unrepaired, triggering the rapid development of cell mutations that may spread locally or throughout the body. A dermatologist diagnoses skin cancer, and when caught at an early stage, it can be treated effectively.
Here is an overview of the four main types of skin cancer.
Squamous Cell Carcinoma (SCC)
SCC can occur when DNA damage triggers abnormal squamous cells. They are commonly found on exposed body areas damaged by UV rays like the chest and hands. While doctors can successfully treat most SCCs, if left untreated, this type of cancer can become invasive, grow into deeper layers of skin, and spread to other body parts.
Melanoma develops when melanocytes proliferate and grow out of control. It's one of the most common types of skin cancer, but melanoma is generally curable for most people when detected and treated early. There are four types of melanoma, superficial spreading melanoma, lentigo maligna, acral lentiginous melanoma, and nodular melanoma.
Basal Cell Carcinoma (BCC)
Basal cell carcinoma arises from the uncontrollable growth of basal cells after exposure to UV radiation. It's the most common type of skin cancer; however, it grows and spreads relatively slowly, so it's mostly curable when caught in the early stages.
Merkel Cell Cancer
Merkel cell carcinoma (MCC) tumors, whilst rare, tend to progress very rapidly. They can often appear on sun-exposed areas of the body. With early detection, doctors can successfully treat MCC in patients.
Skin cancers range from being easy-to-spot to being notoriously difficult to identify. Knowing the typical signs and symptoms of different skin cancers can make it a lot easier to flag suspicious lesions early.
Skin cancer is the abnormal or unregulated growth of skin cells. There are two main types of skin cancer: melanomas and non-melanoma skin cancers. The non-melanoma skin cancers can be further divided into basal cell carcinomas (BCC) and squamous cell carcinomas (SCC). Here are the symptoms to look out for:
Basal cell carcinoma
BCC is the most common skin cancer in the U.S. Typically occurs on:
A lesion that refuses to heal or consistently oozes or crusts over. Sometimes the sore may appear to heal, but after a short while, it reappears again.
Reddish, irritated patch that may itch, scale, hurt, or even cause no discomfort at all.
Shiny bump or nodule that may be pearly, clear, pink, red, or tan.
Pink or pearly nodule with a rolled, raised edge and a central indentation that may ulcerate or crust. Tiny blood vessels may develop on the surface of the lesion.
Scar-like areas that may be white or yellow. Usually, the borders are ill-defined, and the skin appears shiny and taut.
Squamous cell carcinoma
Typically occurs on:
Back of hand
Back of forearm
Rough, scaly patch or plaque, occasionally with a raised border and “collapsed” central appearance.
Color may vary between red, pink, white, and brown.
It can be crusty or flaky.
May sometimes have the appearance of a wart or verruca-like lesion. This type of SCC tends to occur on the foot, genitals, or in the mouth.
It bleeds frequently or easily and does not heal as you would expect it to.
May form as spontaneous lesions or develop in existing moles.
Typically occurs on:
Soles of the feet, palms of the hand, and fingernail beds—usually in people with darker skin
Characteristics of melanoma:
This ABCDE method is a useful way to distinguish between normal moles and melanomas.
Asymmetrical: the lesion has an irregular shape
Irregular border: the border of the mole is irregular
Color: the color of the lesion is blotchy and uneven
Diameter: a mole that grows larger than 6mm in diameter may be a melanoma
Evolving: watch for moles that change with time or that become itchy or start bleeding with minimal contact
The only way to be sure that a lesion is not cancerous is to have it reviewed under a microscope after biopsy or removal. However, the following are unlikely to be malignant and can usually just be monitored using the ABCDE method:
Typical skin tags—usually found in areas of the body that rub against each other, such as under the arms or breasts.
Freckles—small, flat, pigmented lesions that have been present since childhood and usually fade without sun exposure.
Age spots—also called liver spots or solar lentigines. Common in people over the age of 50. Typically present on areas of skin that have been exposed to the sun or that are sun-damaged. Can co-exist with skin cancers.
The vast majority of skin cancer is completely curable if it is caught early¹. When diagnosis and treatment of skin cancer are delayed, the risk of death increases significantly.
Skin cancer can result from various factors that increase the development of skin mutations and moles. Cancer cells rapidly multiply and uncontrollably divide due to mutations within our genes. This can be due to direct environmental factors that cause lasting damage to your skin, or risk factors accumulated during your lifetime. They include:
Prolonged exposure to UV light
UV radiation damages the skin. This can be from the sun, tanning beds, or UV light in nail salons. While the body can repair some DNA damage in skin cells, it can’t fix it all. Generally, the degree of damage is dependent on the intensity of the UV rays and how long the skin has been exposed. Sunburn, due to persistent UV exposure, has also been shown to play an essential role in developing melanoma. Melanoma is known as the most dangerous of the three most common types of skin cancer.
Your skin pigmentation
People have a higher risk of developing skin cancer if they have lighter skin, hair, and eyes than darker pigmented individuals. Brown- and black-skinned people can usually tolerate higher levels of sun exposure without risk of sunburn or increasing their risk of skin cancer. However, excessive exposure to sunlight can damage all types of skin.
High and constant exposure to strong sunlight and solar UV light is a significant risk factor for developing melanoma. If you live in a country or area with continual sun exposure, your risk of developing skin cancers increases. The highest recorded incidence rate of skin cancer is in Australia, with the U.S. being 17th.
Moles generally accumulate throughout our lives, and individuals with many moles are more likely to develop melanoma. Atypical moles are a combination of genetic and environmental factors and often run in families. Atypical mole syndrome can result from a high prevalence of atypical moles, and individuals who have this syndrome have an incredibly high risk of developing melanoma.
Skin cancer can be genetic. For example, if you have atypical moles plus a family history of melanoma, you have a greater risk of developing melanoma in your lifetime. Other genetic risk factors include sunburning easily, the inability to tan, freckles, fair skin, and light eyes.
The causes of skin cancer are complex and will vary on an individual basis. If you have some of these risk factors, it pays to get your skin regularly checked by a health professional.
There are many different treatment options for skin cancer. Which treatment or combination of treatments you end up getting will depend on various factors, including which skin cancer type you have been diagnosed with and how far it may have progressed.
Below is a table outlining the various treatment options for skin cancer and when they are indicated for use. It also gives an idea of how they work, their side effects, or what special precautions to take when undergoing treatment.
Ultimately, your choice of skin cancer treatment is a clinical decision that needs to be made by your doctor in consultation with you and your care team.
Different cancers respond better to different treatment options, and cancers at different stages require specific management.
Skin cancer is the most commonly diagnosed cancer in the U.S.—around 9,500 new cases are diagnosed daily. The good news is that skin cancer is easily preventable, and there are many ways to reduce your risk of developing this disease. Read on for top tips on skin cancer prevention.
Approximately 90% of non-melanoma skin cancers and 86% of melanomas¹ are caused by ultraviolet (UV) radiation from the sun. UV rays cause damage to skin cells, which can trigger cancerous changes.
You can limit the damage caused by the sun by following sun safety guidelines.
Avoid the sun at peak times, between 9am and 3pm
Stay in the shade whenever possible
Wear clothes that cover your arms and legs—fabrics with a tight weave that are darker in color provide better protection
Wear a wide-brimmed sun hat that provides cover for your face, ears, and neck
Wear sunglasses that have a UV filter
Wear sunscreen with a sun protection factor (SPF) greater than 15
Some extra information on sunscreen:
Sunscreen is safe and non-toxic².
Sunscreen does expire, so check the expiry date. Sunscreen past its expiry date may not provide the protection that it’s supposed to.
You should use sunscreen with an SPF of at least 15³. Some organizations recommend a minimum SPF of 30⁴.
Sunscreen should not be used in infants under six months. Infants under six months of age should not be taken into direct sunlight during peak sun exposure times.
Make sure that you use a broad-spectrum sunscreen that protects against UVA and UVB rays.
Some sunscreens have been shown to cause damage to coral reefs, so if you are concerned about protecting the environment, choose a sunscreen that doesn’t contain oxybenzone (check the ingredient list: sunscreen in the U.S. is required to list ingredients).
Sunscreen should be reapplied every two hours and after swimming, exercising, or showering.
Prevent skin cancer by avoiding the following:
Tanning beds/indoor tanning devices
Extensive periods of time in the sun, e.g., exercising during peak sun exposure hours
Nicotinamide: Oral nicotinamide (a form of vitamin B3) was shown in one study⁵ to help prevent the development of new non-melanoma skin cancers in at-risk patients who had a previous history of skin cancer.
Non-steroidal anti-inflammatories (NSAIDs): NSAIDs have been shown to decrease some forms of skin cancer⁶; however, NSAIDs have many side effects and are not generally considered safe to be taken on an ongoing basis.
Oral polypodium leucotomos: Polypodium leucotomos is a plant extract that has shown⁷ some potential in limiting free radical damage to the skin from the sun; however, further research needs to be done to confirm these findings.
The following have NOT been found to be effective⁸ in preventing skin cancer: beta carotene, selenium, and alpha-difluoromethylornithine (DFMO). Isotretinoin has been found to help prevent skin cancer only in people with xeroderma pigmentosum.
Skin Cancer Facts & Statistics | Skin Cancer Foundation
How Safe is Your Sunscreen? | American Cancer Society
Sun Safety | CDC
How Safe is Your Sunscreen? | American Cancer Society
Skin Cancer Prevention (PDQ®) | Yale Cancer Center
Two important things we know about skin cancer are:
It’s easy to prevent.
It’s almost always curable if it’s caught early.
Even if you have no medical education, you can still teach people how to stay safe in the sun and why it’s important to screen their skin regularly.
Here are some ways skin cancer awareness and education have improved skin cancer outcomes:
Since the link between UV radiation and skin cancer¹ was established, many schools have made it compulsory for children to wear broad-brimmed hats and sunscreen when outside during the day.
Free skin cancer screening clinics² have conducted more than 2.8 million skin cancer screenings, with more than 278,000 suspicious lesions detected and more than 31,500 suspected melanomas. This has saved countless lives.
In 2014, the FDA classified UV tanning devices (tanning beds) as Class II carcinogens³. It’s now illegal for people under 18 to use indoor tanning devices in many states. The effect of this is that the incidence of melanoma in people under 29 has dropped by 4% per year between 2005 and 2015⁴.
What’s being done to raise skin cancer awareness?
May is Skin Cancer Awareness Month. This month is used to raise awareness amongst the general public of the prevalence of skin cancer and educate people on how to be sun-safe.
Black ribbons are worn to show support for people with melanoma, and orange ribbons are sold to raise awareness and funds for skin cancer prevention.
What you can do to help raise awareness of skin cancer
1. Share the facts
Social media is an excellent tool for spreading information fast and effectively. Use various foundation toolkits to make it easy for you to post reliable, meaningful information on your social media accounts.
2. Become an advocate for skin cancer prevention
Becoming an advocate for skin cancer prevention⁵ gives you the opportunity to push for changes in legislation to improve skin cancer outcomes and take action in the fight against skin cancer.
3. Tell your story
Tell the story of how skin cancer has affected your life. People connect with personal stories. Use the hashtag #ThisIsSkinCancer.
4. Start a fundraiser or donate to an organization that supports skin cancer awareness
There are many opportunities to raise or donate money to organizations that help spread awareness about skin cancer or support those who have skin cancer.
When you receive a skin cancer diagnosis, the last thing that you want to think about is the financial implications. There is the cost of the treatment itself and the hidden costs of time away from work and extra support to factor in.
The cost of a skin cancer diagnosis will vary greatly depending on what type of skin cancer it is, where it is on your body, and how advanced it is.
Generally, non-melanoma cancers (basal cell carcinoma, BCC, and squamous cell carcinoma, SCC) are cheaper to treat than melanomas, especially if they are caught early.
Americans have had access to free skin cancer screening¹ since 1985. The first choice would be to utilize this service; however, you may want to visit your doctor for skin screening if you are unable to.
Dermatology consultations can cost around $175 if you don’t have health insurance. The copayment, if you do have insurance, will be about $30.
If you need to have a biopsy of a skin lesion during screening, there can be added costs above this.
Treating skin cancer can be scarily expensive. If you are feeling lost or overwhelmed or thinking of actually ignoring your cancer diagnosis because you can’t afford treatment, or even if you just have no idea where to begin to look for support, the Robin’s Nest² initiative offers wonderful guidance.
The program provides you with a carefully curated list of organizations that offer assistance with insurance, health care costs, transportation, coping support, and other issues that arise with a skin cancer diagnosis.
Skin cancer is the most common cancer¹ in America. Current estimates are that one in five Americans will develop skin cancer in their lifetime: that’s 9,500 new skin cancer diagnoses in the U.S. per day.
Basal cell carcinomas (BCC) and squamous cell carcinomas (SCC)—both non-melanoma skin cancers—are far more common globally and in the U.S. than melanomas, but their prevalence is often under-reported. This is because BCC and SCC are non-aggressive, slow-growing cancers that are usually treated fully by general practitioners.
There is no requirement for BCC or SCC to be listed on the national cancer registry in the U.S., so it’s difficult to collate accurate data about these extremely common cancers.
Melanomas are more aggressive cancers usually managed by specialists, so reporting of melanomas is far more regulated. Although melanomas are not as common as non-melanoma skin cancers, the data for their prevalence is more accurate and easily accessible.
How prevalent is skin cancer in the U.S.?
Current estimates² for 2021 are that three million Americans live with either BCC or SCC, and more than one million live with melanoma.
There is a similar trend of increasing incidence of skin cancer globally as there is in the U.S. Worldwide, it is estimated³ that two to three million people will be given a new diagnosis of non-melanoma skin cancer this year and around 132,000 a diagnosis of melanoma.
Factors influencing skin cancer prevalence
Numerous factors influence the incidence of skin cancer in an area:
Age—skin cancer is more prevalent in older populations
Ethnicity—Caucasians are over 20 times more likely to get skin cancer than people with skin of color
Ozone layer—areas with a thinner ozone layer are exposed to stronger UV radiation
Altitude—areas at higher altitudes have more UV radiation
Gender—females are more likely than males to be diagnosed with non-melanoma skin cancer. Under 50, females are more likely to develop melanomas, and over 50, males are more likely to be diagnosed with melanomas.
Skin cancer survival and mortality
BCC and SCC have very high survival rates since they are non-aggressive tumors that don't often metastasize.
The overall five-year survival rate⁴ for melanoma is 92.7%. This means that out of 100 people diagnosed with melanoma at any stage, almost 93 will still be alive five years after diagnosis.
The vast majority of skin cancer deaths are from melanomas. The mortality rate of melanoma⁵ in the U.S. in 2018 was two people per 100,000 (or 0.002%). The mortality rate of BCC and SCC is so negligible that it is unknown.
Skin Cancer | American Academy of Dermatology Association
Skin Cancer | American Academy of Dermatology Association
Radiation: Ultraviolet (UV) radiation and skin cancer | World Health Organization
Skin Cancer Prognosis and Survival Rates | SkinCancer.net
What is skin cancer?
Skin cancer is an abnormal, unregulated growth of skin cells. There are two main types of skin cancer: melanomas and non-melanoma skin cancers. Non-melanoma skin cancer can be divided into basal cell carcinomas (BCC) and squamous cell carcinomas (SCC).
What causes skin cancer?
The ultraviolet (UV) radiation from the sun is the main cause of skin cancer. 90% of skin cancers¹ are directly attributable to sun damage.
Tanning beds are also a major cause of skin cancer. Less common causes of skin cancer are infection with human papillomavirus and chronic inflammation in old burns or scar tissue.
Can you prevent skin cancer?
There are lots of simple measures that you can take to prevent skin cancer. Wearing sunblock, sun hats, and sun-occlusive garments all protect from UV radiation. Staying out of the sun during peak hours (9am- 3pm) goes a long way toward preventing sun damage to your skin.
One of the most important ways to prevent skin cancer is to get your skin checked regularly by a doctor so that they can remove any suspicious-looking lesions early.
Can skin cancer spread?
Yes, skin cancer can spread. Basal cell carcinoma and squamous cell carcinoma are not very aggressive and take longer to spread to distant organs. If left for too long, they can spread locally to invade nerves and other surrounding tissue.
Melanomas are more aggressive and spread early to distant organs, especially the lungs, liver, and brain. The key is to catch them early before they have the chance to spread.
Can you treat skin cancer?
Yes. The most important take-home message is that if you catch skin cancer early, it is fully treatable. If you diagnose a skin cancer before it spreads, it can be simply excised. Once it has spread, multiple treatment options are available, but the treatment becomes more complicated.
What does skin cancer look like?
Skin cancers can present in all sorts of different ways, but the following things are some warning signs to look out for:
A lesion that doesn’t heal
A lesion that is irregular in color or form
A lesion that bleeds easily
A mole that is growing or changing in shape or color
Can Black people get skin cancer?
Yes. Black people have more melanin in their skin, which protects them to some degree from sun damage. Black people, however, can still get skin cancer in areas with a lot of sun exposure. Black people can also get skin cancers that aren’t caused by sun exposure.