What the three main types of skin cancer look like
The three most common skin cancers—basal cell carcinoma, squamous cell carcinoma, and melanoma—each have a recognizable appearance, though none looks the same in every person. Basal cell carcinoma often appears as a shiny bump or a flat, scaly patch that may bleed or ooze. Squamous cell carcinoma typically shows up as a rough, raised bump or a flat sore that doesn't heal. Melanoma is the most dangerous type and usually appears as a dark spot or mole that has changed shape, size, or color, or as a new growth that looks different from your other moles.
The key difference between these cancers and normal skin growths is change over time. A mole you've had since childhood that hasn't changed is almost certainly not cancer. A spot that appeared recently, or one that has grown, darkened, or changed shape in the past few months, warrants a closer look from a dermatologist.
Key Takeaways
- Basal cell carcinoma often looks like a shiny, translucent bump or a flat, scaly patch that may bleed or crust over.
- Squamous cell carcinoma typically appears as a rough, raised bump or a sore with a hard center that doesn't heal.
- Melanoma commonly shows up as a dark mole or spot with irregular borders, uneven color, or a diameter larger than a pencil eraser.
- Any mole or spot that changes in size, shape, color, or texture over weeks or months should be examined by a dermatologist.
- Skin cancer can develop on any part of your body, including areas that don't get much sun exposure.
Basal cell carcinoma: the most common type
Basal cell carcinoma accounts for about 80 percent of all skin cancers and grows slowly. It usually appears on sun-exposed skin, especially the face, ears, scalp, and neck. The growth often looks like a small, shiny, flesh-colored or slightly pink bump with a rolled edge and a depression or ulcer in the center. Some basal cell carcinomas look more like a flat, scaly patch of skin that may be red or tan.
A telltale sign is that the spot may bleed, ooze, or crust over, then seem to heal, then bleed again. This cycle can repeat over months or years. The growth is usually painless and doesn't itch, so people often ignore it. Because basal cell carcinoma grows slowly and rarely spreads to other parts of the body, it has an excellent outlook when caught and treated early.
Squamous cell carcinoma: the second most common type
Squamous cell carcinoma makes up about 20 percent of skin cancers and also develops on sun-exposed areas, though it can appear anywhere on the body. It typically looks like a rough, raised bump with a scaly or crusted surface, sometimes with a hard center. The spot may be red, pink, or tan, and it often feels rough or tender to the touch.
Unlike basal cell carcinoma, squamous cell carcinoma can grow more quickly and has a higher risk of spreading if left untreated. A sore that doesn't heal within a few weeks, especially one that bleeds or becomes increasingly tender, should be examined. Squamous cell carcinoma is still highly treatable when caught early, but the sooner you see a dermatologist, the simpler the treatment is likely to be.
Melanoma: the most dangerous type
Melanoma is the least common of the three but the most serious because it spreads more readily to other parts of the body. It often starts as a change in an existing mole or as a new, unusual-looking spot. The classic warning signs are captured in the ABCDE rule: Asymmetry (one half doesn't match the other), Border irregularity (edges are jagged or blurred), Color variation (multiple shades of brown, black, red, or even white), Diameter larger than a pencil eraser (about 6 millimeters), and Evolution (the spot has changed in size, shape, or color in recent weeks or months).
Melanoma can be brown, black, tan, red, or even skin-colored, so color alone doesn't determine whether a spot is dangerous. What matters most is change. A mole that has grown, darkened, or developed an irregular border in the past few months needs evaluation. Melanoma can also appear as a new growth that looks different from all your other moles—dermatologists call this the "ugly duckling" sign. Early detection makes a major difference in outcomes, so any spot that fits the ABCDE pattern or stands out from your other moles should be checked promptly.
Where skin cancer appears on your body
Most skin cancers develop on areas exposed to the sun, particularly the face, ears, scalp, neck, chest, and the backs of the hands and arms. However, skin cancer can appear anywhere on your body, including areas that rarely see sunlight. Melanoma, in particular, can develop on the soles of the feet, between the toes, under the fingernails, on the genitals, or inside the mouth.
This is why it's important to check your entire body regularly, not just the obvious sun-exposed spots. Many people discover skin cancer on their legs, back, or other areas they don't think about as often. If you have a partner or family member, ask them to check areas you can't see easily, such as your scalp and the back of your neck.
How to examine your skin at home
A monthly self-examination takes about 10 minutes and helps you notice changes early. Use a mirror in a well-lit room, and if possible, use a hand mirror to check the back of your body. Start at your head and work downward, looking at your face, ears, scalp (part your hair to see the skin underneath), neck, chest, and arms. Then examine your hands, fingernails, and the spaces between your fingers and toes.
Sit down to check your legs, thighs, shins, and the tops and soles of your feet. Use a hand mirror to look at your back, buttocks, and genital area. If you have many moles, take photos of them with your phone so you can compare them month to month and spot changes more easily. Pay special attention to any spot that is new, growing, changing color, or looks different from your other moles. If you notice anything concerning, schedule an appointment with a dermatologist rather than waiting to see if it changes.
When to see a dermatologist
You don't need to wait for a spot to match every feature of the ABCDE rule before seeing a dermatologist. Any of these warrant a professional evaluation: a new mole or growth that appeared recently, a mole that has changed in size, shape, or color over the past few weeks or months, a spot that bleeds, oozes, or doesn't heal, a growth that itches or is tender, or any spot that simply looks different or unusual to you.
Dermatologists are trained to recognize skin cancer at early stages when treatment is most straightforward. A biopsy—a small tissue sample examined under a microscope—is the only way to confirm whether a growth is cancer. If you're unsure whether a spot needs checking, it's better to have a dermatologist look at it than to worry or delay. Early detection of skin cancer, especially melanoma, significantly improves outcomes and often allows for simpler, less invasive treatment.
Frequently Asked Questions
Can skin cancer itch or hurt?
Most early skin cancers don't cause pain or itching, which is why they're easy to miss. However, some people do report itching, tenderness, or a burning sensation. The absence of pain doesn't mean a spot is safe—many dangerous melanomas are painless. If a mole or spot itches persistently or becomes tender, have it checked.
What's the difference between a normal mole and a cancerous one?
Normal moles are usually uniform in color, have smooth or slightly raised borders, and don't change over time. Cancerous moles often have irregular borders, multiple colors, asymmetrical shape, or a diameter larger than a pencil eraser. The most important difference is change: a mole that has grown, darkened, or altered its appearance in recent months needs evaluation.
Can skin cancer appear on skin that doesn't get much sun?
Yes, especially melanoma. While sun exposure is the main risk factor for most skin cancers, melanoma can develop on areas rarely exposed to sunlight, including the soles of feet, between toes, under nails, and in the mouth. This is why checking your entire body, not just sun-exposed areas, matters.
How quickly does skin cancer grow?
Growth rate varies by type. Basal cell carcinoma grows slowly over months or years. Squamous cell carcinoma grows faster. Melanoma can grow rapidly and spread, which is why any change in a mole warrants prompt evaluation. Don't wait to see if a spot grows—have a dermatologist assess it.
Is every changing mole cancer?
No. Many benign skin growths change slightly over time. However, any mole that changes noticeably in size, shape, or color—or any new growth that looks unusual—should be examined by a dermatologist. They can determine whether the change is harmless or requires further investigation.