Basal cell carcinoma and squamous cell carcinoma are the two most common cancers in the United States. Together they account for roughly 5.4 million cases a year, according to the American Cancer Society.
Skin cancers are by far the most common cancer type in the country, and about 8 out of 10 of them are basal cell carcinomas. About 1.8 million SCC cases are diagnosed each year, per the Skin Cancer Foundation.
Neither looks like a mole. The familiar ABCDE rule for spotting melanoma won't help you catch them.
The Skin Cancer Foundation and the American Cancer Society describe basal and squamous cell tumors as pearly bumps, non-healing sores, scaly red patches and waxy scar-like areas. That is why they are so often written off as eczema, a nick that won't close, or an age spot.
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Here are the seven appearances dermatologists want you to know.
1. A pearly or translucent bump
A small, shiny bump that looks pearly, pink, red or clear is a classic sign of basal cell carcinoma.
The Skin Cancer Foundation notes the bump can also be pigmented tan, black or brown. In lighter skin, the ACS describes it as translucent and shiny, sometimes with blue, brown or black areas inside.
2. An open sore that won't heal
A sore that bleeds, oozes or crusts for weeks, or heals and then comes back, is a warning sign of both basal cell and squamous cell carcinoma. It is the single most cited red flag in ACS guidance on skin cancer symptoms.
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3. A scaly red patch with irregular borders
A persistent, scaly red patch with uneven borders that sometimes crusts or bleeds points toward squamous cell carcinoma. It can itch, hurt or feel like nothing at all.
Surrounding skin usually shows other signs of sun damage, according to the Skin Cancer Foundation.
4. A pink growth with a raised, rolled edge
A small pink growth with a slightly raised, rolled border and a crusted indentation in the center is another common face of basal cell carcinoma. The shape can slowly enlarge and is often confused with a pimple that never quite goes away.
5. A flat, scar-like lesion
A flat white, yellow or waxy patch that resembles a scar is one of the trickiest forms of basal cell carcinoma to spot.
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The ACS describes it as "flat, firm, pale or yellow areas, similar to a scar, showing only slight changes from normal skin."
6. Tiny visible blood vessels
Small, abnormal blood vessels running across a bump or growth are a red flag for basal cell carcinoma. The ACS lists them among the classic features of pink BCC growths, and they often appear on the surface of a small pink lesion over time.
7. A wart-like growth
A wart-like growth that crusts and occasionally bleeds is a hallmark of squamous cell carcinoma. Unlike an ordinary wart, it does not go away with time and tends to keep growing.
When to see a doctor
The American Cancer Society advises checking with a doctor about any new or changing skin growth, any sore that does not heal, or any area that concerns you.
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That applies especially to sun-exposed skin such as the face, ears, scalp, neck, chest, arms and hands.
Monthly head-to-toe self-exams and yearly professional skin checks are the Skin Cancer Foundation's baseline recommendation, and people with a prior skin cancer or precancer should follow shorter screening intervals set by their dermatologist.
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This article is made and published by Ida-Marie Palm Varbæk, who may have used AI in the preparation.