How to Spot Different Types of Skin Cancer
For such a prevalent disease—it’s the most common cancer in the United States, according to the Centers for Disease Control and Prevention—there are so many misconceptions about skin cancer. One biggie: The belief that there’s just one kind. While melanoma is the most well-known, likely because it’s responsible for the majority of skin cancer deaths, about 20% of individuals will develop a non-melanoma skin cancer in their lifetime. Now for the good news: If you understand the basics of the most common types, and know what to look for, you can be diligent and keep your skin safe.
Basal Cell Carcinoma
Basal cell carcinoma (BCC) is the most prevalent type of skin cancer, accounting for 80% of all cases. It develops in the basal layer of the epidermis (top layer of the skin) and is most often related to DNA damage from sun exposure. “For the most part, basal cell carcinoma doesn’t spread to other parts of the body,” says Kimberly Brady, M.D., director of dermatologic surgery at Roswell Park Comprehensive Cancer Center Buffalo, NY. Still, don’t ignore it. “If left untreated, it’ll grow bigger and deeper.” This can be especially worrisome if it’s situated near the eyes or nose, where it can interfere with seeing or breathing.
What Does Basal Cell Carcinoma Look Like?
BCC usually surfaces on the face, head, and neck, and while it can look different on every person, it often appears as an open sore, a red patch, a pink or shiny bump, or a flat white, yellow or waxy-looking splotch. “But about 50% of basal cell carcinomas are brown or glassy-black on darker-skinned individuals, not the pink, pearly growth that appears on fair skin,” says board-certified dermatologist Valerie M. Harvey, M.D., co-director of Hampton University Skin of Color Research Institute in Hampton, VA.
Squamous Cell Carcinoma
DNA damage from the sun is the main driver behind squamous cell carcinoma (SCC), the second most common form of skin cancer. It grows in the top layer of skin and can also be found to grow into the deep layers of the dermis. No matter, early treatment is imperative. “What may have been a small procedure when the tumor was at an early stage, can turn into extensive reconstruction as the cancer progresses,” says Dr. Brady. Plus, a small percentage of people—particularly those with SCC on the lips or ears and folks with compromised immune systems—develop aggressive squamous cell carcinoma, where the cancer recurs and spreads.
What Does Squamous Cell Carcinoma Look Like?
Like basal cell carcinoma, SCC is most likely to appear on sun-exposed areas of the body, such as the face, lips, ears, scalp, shoulders, neck, hands, and forearms. But it can occur in other areas, like the genitals, too, according to the Skin Cancer Foundation. (SCC on the genitals is usually associated with the human papillomavirus, or HPV, infection.) Look for scaly red patches; wart-like growths; raised bumps with a central depression; or open sores that crust over, itch, or bleed. For darker skinned individuals, SCC is still scaly, but often brown or black in color, notes Dr. Harvey.
Melanoma develops in melanocytes, cells that churn out melanin, giving skin its color. “About one in 10 people with melanoma has a family history, whereas 90% are caused by UV exposure,” says Anne Marie McNeill, M.D., a board-certified dermatologist in Newport Beach, California and member of The Skin Cancer Foundation. “On average, a person’s risk doubles having had more than five sunburns.” While melanoma accounts for about 1% of all skin cancers cases in the U.S., because it can spread to other areas of the body, it’s responsible for the majority of skin cancer deaths, according to the American Cancer Society. However, “when melanoma is diagnosed early, it’s associated with a better prognosis and higher rates of survival,” says Dr. Harvey.
What Does Melanoma Look Like?
If an existing mole changes shape, color (uneven shading), size, or feel (elevation or irregular border), it may be melanoma. Same is true if a new mole-like spot suddenly appears. (Asymmetry and color variation are also clues.) Melanoma can show up anywhere, but most often develops on the chest and back (in men) and on the legs (in women). “Acral melanoma, a subtype of melanoma, occurs on palms, soles, and beneath the fingernails and toenails,” says Dr. Brady. “This is the most common type of melanoma among darker-pigmented individuals.” It often appears as a black, brown, or blue patch. “The area may itch, be painful, ulcerate, or even bleed,” says Dr. Harvey.
Merkel Cell Carcinoma
Merkel cell carcinoma (MCC) is a rare skin cancer, with about 2,000 cases in the U.S. each year. “It’s also the most deadly skin cancer,” says Dr. McNeill, noting that this disease can spread quickly and recur. Another reason MCC is dangerous: “Patients are often told by their primary care doctors that the growth is a cyst, when it’s not,” says Dr. McNeill. Merkel cell carcinomas often grow on the head or neck and appear as slightly hard and painless pink, red, or purple bumps. Like other skin cancers, MCC is related to sun exposure. Other risk factors include being over age 50 and/or having a weakened immune system.
Sebaceous Gland Carcinoma
Sebaceous carcinoma forms in the oil glands and is a painless, round, and shiny bump that’s pink or yellowish. “It can grow anywhere, but mostly on the eyelid, where it can be confused with a stye,” says Dr. McNeill. The cause is unclear, but older individuals, those of Asian descent, and folks with a weakened immune system are at greater risk. Sebaceous carcinoma is slow-growing, so it’s easy to ignore. Don’t. “It can be deadly, and it can also be a sign to look for cancer elsewhere,” Dr. McNeill. Sebaceous carcinoma is associated with a genetic cancer syndrome called Muir-Torre syndrome, which elevates one’s risk of other cancers, like colorectal cancer.
Dermatofibrosarcoma protuberans (DFSP) is a rare and slow-growing soft tissue sarcoma that develops in the deep layers of the skin. “The first sign may be a reddish brown patch of raised skin that looks like a scar, and over time, lumps can appear within it,” says Dr. Brady. “The tumors can grow quite large, and can invade the underlying fat, muscle, and even bone.” DFSP is usually found on arms, legs, and the trunk and it impacts more Black individuals than other ethnicities. “Because DFSP can grow quite large before they’re detected, it may take more than one surgery to completely remove the cancer, which can be disfiguring,” says Dr. McNeill.
Kaposi sarcoma (KS) appears as lesions on the skin (usually the face or legs) or in mucous membranes, such as inside the mouth. KS is a vascular neoplasm caused by the herpesvirus 8 (HHV8) and is locally aggressive. “When on the skin, KS appears as a painless red or violet flat patch or patches—or a raised plaque,” says Dr. Harvey. The most common type of KS found in the U.S. is linked to AIDS and very rare. (About 6 cases per 1 million people each year.) “Before AIDS, Kaposi sarcoma was usually confined to young men of Africa descent or older men of Mediterranean descent,” says Dr. McNeill.
Skin Cancer Stats: Centers for Disease Control and Prevention (CDC). (2015.) “Preventing Melanoma.” cdc.gov/vitalsigns/melanoma/
Nonmelanoma Numbers: JAMA Dermatology. (2010.) “Prevalence of a History of Skin Cancer in 2007: Results of an Incidence-Based Model.” jamanetwork.com/journals/jamadermatology/fullarticle/209761
Melanoma Rates: American Cancer Society. (2020.) “Cancer Statistics Center.” cancerstatisticscenter.cancer.org
Who Gets Basal Cell Carcinoma?: American Cancer Society. (2019.) “What Are Basal and Squamous Cell Skin Cancers?” cancer.org/cancer/basal-and-squamous-cell-skin-cancer/about/what-is-basal-and-squamous-cell.html
Spotting Basal Cell Carcinoma: Skin Cancer Foundation. (2020.) “Basal Cell Carcinoma Overview.” skincancer.org/skin-cancer-information/basal-cell-carcinoma
Where to Find Squamous Cell Carcinoma: Skin Cancer Foundation. (2019.) “Squamous Cell Carcinoma: Warning Signs.” skincancer.org/skin-cancer-information/squamous-cell-carcinoma/scc-warning-signs-and-images/
How Common is Melanoma?: American Cancer Society. (2020.) “Key Statistics for Melanoma Skin Cancer.” cancer.org/cancer/melanoma-skin-cancer/about/key-statistics.html
Melanoma Clues: National Cancer Institute. (2011.) “What Does Melanoma Look Like?” cancer.gov/types/skin/melanoma-photos
Merkel Cell Carcinoma Risk Factors: Skin Cancer Foundation. (2020.) “Merkel Cell Carcinoma Overview.” skincancer.org/skin-cancer-information/merkel-cell-carcinoma/
What’s Kaposi Sarcoma?: American Cancer Society. (2018.) “What Is Kaposi Sarcoma?” cancer.org/cancer/kaposi-sarcoma/about/what-is-kaposi-sarcoma.html