Skin cancer doesn’t have one single look. It can appear as a pearly bump, a scaly red patch, a dark streak under a fingernail, or a mole that’s changed shape over the past few weeks. The specific appearance depends on the type of skin cancer and your skin tone, but there are reliable visual patterns you can learn to spot on your own body.
Basal Cell Carcinoma: The Most Common Type
Basal cell carcinoma accounts for the majority of skin cancers and tends to grow slowly. On lighter skin, it typically appears as a shiny, translucent bump with a pearly white or pink quality. You might notice tiny blood vessels running across the surface. On brown and Black skin, basal cell carcinoma often looks like a brown, glossy black, or tan bump with a rolled border.
Not all basal cell carcinomas look like bumps, though. Some show up as a flat, scaly patch with or without a raised edge. Others resemble a white, waxy, scar-like area with no clearly defined border. One of the most telling signs is a sore that won’t heal: it may bleed, scab over, and then reopen repeatedly over weeks or months. If you have a spot like that, it’s worth getting checked even if it doesn’t look dramatic.
Squamous Cell Carcinoma: Scaly and Crusty Spots
Squamous cell carcinoma tends to show up on parts of your body that get the most sun: the scalp, ears, backs of the hands, and lips. But it can also develop inside the mouth, on the bottoms of the feet, or on the genitals.
The classic appearance is a flat sore with a scaly crust, or a rough, scaly patch that may feel like sandpaper. On the lip, it can start as a rough patch and progress to an open sore. Some squamous cell carcinomas look more like raised, wart-like bumps. On darker skin, these lesions can be the same color as your skin, or they can appear pink, red, black, or brown, which makes them easier to overlook. A firm bump or raised area on an old scar is another pattern to watch for.
Melanoma: The ABCDE Warning Signs
Melanoma is less common than basal or squamous cell carcinoma but far more dangerous because it can spread to other organs. It often develops from an existing mole or appears as a new dark spot on the skin. Dermatologists use the ABCDE rule to describe its early features:
- Asymmetry: One half of the mole doesn’t match the other half.
- Border: The edges are ragged, notched, or blurred rather than smooth. Pigment may spread into the surrounding skin.
- Color: Multiple shades are present. You might see brown, tan, and black mixed together, along with patches of white, gray, red, pink, or blue.
- Diameter: Most melanomas are larger than 6 millimeters wide (roughly the size of a pencil eraser), though they can start smaller.
- Evolving: The mole has changed in size, shape, or color over the past few weeks or months.
On darker skin, melanoma can look like a dark or black bump that appears waxy or shiny. The most common form of melanoma in people with dark skin is acral lentiginous melanoma, which develops on the palms, soles of the feet, fingers, toes, and nail beds. These are areas that don’t get much sun, which is why skin cancer in darker skin tones is often caught late.
The Ugly Duckling Sign
Beyond the ABCDE rule, there’s a simpler way to spot a suspicious mole: look for the one that doesn’t match the rest. Most of your moles will share a general appearance. The “ugly duckling sign” is a mole that stands out from its neighbors in color, size, or shape. If one mole looks noticeably different from every other mole on your body, that’s the one worth having examined.
Skin Cancer Under Your Nails
Subungual melanoma appears as a dark, vertical streak running from the bottom of your nail to the top. It looks like someone drew a line on the nail with a black or brown marker. The streak is usually less than 3 millimeters wide at first but can widen over time, eventually covering the entire nail and extending into the cuticle. The color may be uneven, with varying shades of blackish brown. The discoloration can also spread to the skin around the nail.
This type is easy to dismiss as a bruise or fungal infection. The key difference is that a bruise under the nail grows out with the nail over weeks, while a melanoma streak stays in place or gets wider. If you notice a persistent dark line under one nail, especially on your thumb or big toe, it deserves a closer look.
What Precancerous Spots Look Like
Not every concerning spot is cancer yet. Actinic keratoses are precancerous patches caused by years of sun exposure. They appear as rough, dry, scaly patches usually less than an inch across. You often feel them before you see them, because they have a sandpaper-like texture. Colors range from pink to red to brown, and some develop a hard, wart-like surface. They’re flat or only slightly raised. Left untreated, a small percentage of actinic keratoses can progress to squamous cell carcinoma, so treating them early is a straightforward way to reduce your risk.
How Skin Cancer Looks Different on Darker Skin
Most skin cancer images online show examples on light skin, which can make it harder for people with brown or Black skin to recognize the same conditions on their own bodies. Here’s how the major types can differ in appearance:
Basal cell carcinoma may appear as a glossy black or brown bump rather than the classic pearly white. Squamous cell carcinoma can match your natural skin tone, making it nearly invisible unless you notice the texture. Melanoma is more likely to appear on the palms, soles, or under the nails rather than on sun-exposed areas. A dark patch on your palm, the bottom of your foot, or a dark band under a fingernail or toenail are all signs to take seriously.
Merkel Cell Carcinoma: Rare but Fast-Growing
Merkel cell carcinoma is uncommon but aggressive. It appears as a painless, shiny nodule on the skin that can be skin-colored, red, purple, or bluish-red. Its defining feature is speed: these lesions expand rapidly, sometimes growing noticeably over just a few weeks. Because the nodule is painless and can look similar to a cyst or pimple, it’s often ignored until it’s significantly larger. Any fast-growing, painless bump that doesn’t resolve on its own warrants a professional evaluation.
How to Check Your Own Skin
There are no universal screening guidelines in the U.S. recommending routine skin exams by a doctor for people without symptoms or a personal or family history of skin cancer. That means self-checks are your first line of detection. Once a month, examine your entire body in a well-lit room with a full-length mirror and a hand mirror for hard-to-see areas.
Pay attention to the spots people typically skip: the scalp (part your hair and look section by section), between your toes, the soles of your feet, your nail beds, behind your ears, and your lower back. You’re looking for anything new, anything that’s changed, and anything that doesn’t heal within three to four weeks. Take photos of moles you want to track so you can compare them over time. Changes are easier to catch when you have a reference point.