Most new spots, bumps, and moles on your skin are not cancer. But telling the difference between a harmless growth and something dangerous isn’t always obvious, and skin cancer is the most common type of cancer in the United States, with an estimated 112,000 new melanoma cases alone expected in 2026. Knowing what to look for can help you decide whether that spot deserves a closer look from a dermatologist.
What Skin Cancer Actually Looks Like
Skin cancer comes in three main forms, and each one shows up differently on the skin. The type most people worry about is melanoma, which is the most dangerous but also the least common. The other two, basal cell carcinoma and squamous cell carcinoma, are far more frequent and grow more slowly.
Melanoma
Melanoma usually starts in or near an existing mole, or appears as a new dark spot. The ABCDE rule, developed by the National Cancer Institute, is the standard way to evaluate a suspicious mark:
- Asymmetry: One half of the spot doesn’t match the other half.
- Border: The edges are ragged, notched, or blurred, and pigment may spread into surrounding skin.
- Color: The spot contains multiple shades of brown, black, or tan, possibly with areas of white, gray, red, pink, or blue.
- Diameter: Most melanomas are larger than 6 millimeters across (about the size of a pencil eraser), though they can be smaller.
- Evolving: The spot has changed in size, shape, or color over the past few weeks or months.
Any single one of these features is worth noting. If you see two or more, that’s a strong reason to get it checked.
Basal Cell Carcinoma
Basal cell carcinoma is the most common skin cancer and tends to grow slowly. It often looks like a shiny, slightly translucent bump, pearly white or pink on lighter skin, brown or glossy black on darker skin. You might notice tiny blood vessels on its surface. Other forms include a flat, scaly patch with a raised edge, a brown or blue lesion with dark spots, or a white, waxy, scar-like area without a clear border. A hallmark sign is a sore that bleeds, scabs over, and then never fully heals.
Squamous Cell Carcinoma
Squamous cell carcinoma often appears as a firm bump or nodule that can be skin-colored, pink, red, brown, or black depending on your skin tone. It can also show up as a flat sore with a scaly crust, a rough scaly patch on the lip that becomes an open sore, or a new raised area developing on top of an old scar. These growths tend to appear on sun-exposed areas like the face, ears, hands, and arms.
Harmless Spots That Mimic Cancer
Several common, completely benign growths cause unnecessary alarm because they look suspicious. Seborrheic keratoses are among the most frequent offenders. These flesh-colored, brown, or black spots look waxy and wart-like, as though they’ve been stuck onto the skin’s surface. They become more common with age and are harmless despite their sometimes dark, irregular appearance.
Dermatofibromas are small, round, brownish to reddish-purple bumps that often show up on the legs and feel firm to the touch, like a tiny scar under the skin. They’re more common in women and may itch but pose no danger. Cherry angiomas, those bright red pinpoint dots that seem to multiply as you get older, are simply clusters of blood vessels and also completely benign.
The key difference between these harmless growths and skin cancer usually comes down to change. A spot that has looked the same for months or years is far less concerning than one that’s new, growing, changing color, or bleeding.
Pre-Cancerous Spots to Watch
Actinic keratoses are rough, dry, scaly patches that develop on sun-exposed areas like the face, scalp, neck, chest, and backs of the hands. They can be skin-colored or slightly tanned, sometimes with a pinkish-red base. They feel like sandpaper when you run your finger over them. Most actinic keratoses are harmless, and many actually resolve on their own. But having them significantly increases your risk of developing squamous cell carcinoma. A Swedish study following over 17,000 patients found that people with actinic keratoses had nearly 8 times the risk of developing squamous cell carcinoma compared to the general population. If you have several of these rough patches, it’s worth having them monitored and potentially treated.
Skin Tone and Cancer Risk
Skin cancer risk is highest in people with lighter skin, but it is not exclusive to them. People with darker skin have more melanin, which filters UV radiation and provides some natural protection. This does reduce overall risk. However, skin cancer in people of color tends to be diagnosed later and at more advanced stages, which leads to worse outcomes.
In people of African and Asian Indian descent, squamous cell carcinoma is actually the most common type of skin cancer, not basal cell carcinoma. And these cancers sometimes develop in areas that get little sun exposure, like the palms, soles of the feet, and under the nails, making them easy to miss. The old assumption that very dark skin “never burns” has been shown to be inaccurate, and sunburn in darker skin is more common than previously thought.
What Happens if You Get It Checked
A dermatologist will first examine the spot visually, often using a dermatoscope, which is essentially a magnifying lens with a light that reveals structures beneath the skin’s surface invisible to the naked eye. If anything looks suspicious, the next step is a biopsy, where a small sample of skin is removed and examined under a microscope. This is the only way to confirm whether something is cancer.
There are a few types of biopsy, and all are done in the office with local numbing. A shave biopsy slices off the raised portion of a superficial lesion. A punch biopsy uses a small circular tool to remove a deeper core of skin, like a tiny cookie cutter. An excisional biopsy removes the entire growth down to the fat layer and is typically used when cancer is suspected. The wound is closed with stitches and heals over one to two weeks. Results usually come back within a week or two.
How to Check Your Own Skin
A monthly self-exam is the simplest way to catch problems early. The best time is after a shower, in a well-lit room with a full-length mirror and a hand mirror for hard-to-see areas. Go head to toe: scalp (use a hair dryer to part your hair), face, ears, neck, chest, arms, hands (including between fingers and under nails), torso front and back, legs, feet (including the soles and between toes), and genital area.
You’re not trying to diagnose anything. You’re building a mental map of what’s normal for your skin so that when something changes, you notice. Look for any new spots, spots that look different from the others around them, and anything that has changed in size, shape, or color since your last check. A spot that bleeds, itches persistently, or won’t heal after a few weeks is always worth showing to a doctor, regardless of what it looks like.