Skin cancer caused by sun damage can look like a pearly bump, a scaly red patch, a sore that won’t heal, or a mole that changes shape and color. The specific appearance depends on which type of skin cancer develops, but all three major types share one thing in common: they tend to show up on skin that has seen the most sun over your lifetime. Your face, scalp, ears, neck, chest, arms, hands, and legs are the most common sites.
A normal sunburn heals within one to two weeks. Skin cancer, by contrast, doesn’t resolve on its own. It may take years or even decades after sun damage for a cancerous spot to appear, so the lesion you’re looking at now likely isn’t from your last sunburn. It’s the cumulative result of UV exposure over time.
How UV Damage Leads to Skin Cancer
Sunburn is visible proof that ultraviolet radiation has damaged your skin cells at the DNA level. UVB rays, the primary cause of sunburn, create structural defects in your DNA by fusing together the building blocks of your genetic code. Your cells have repair systems that fix most of this damage, but some errors slip through and become permanent mutations. UVA rays cause a different kind of harm, generating reactive molecules inside cells that attack DNA indirectly.
Both types of damage can hit the p53 gene, which acts as your body’s main brake on abnormal cell growth. When that gene stops working correctly, damaged cells can multiply unchecked. This process doesn’t happen overnight. The mutations accumulate with each episode of sun exposure, which is why skin cancer often appears decades after the sunburns that set it in motion. Research on sun exposure patterns in Western Australia found that blistering sunburns between ages 10 and 14 were linked to basal cell carcinoma later in life, while sunburns after age 35 were more closely tied to squamous cell carcinoma.
The dose matters too. A meta-analysis of sunburn studies found that five blistering sunburns during childhood raised melanoma risk by about 80 percent. Adolescent sunburns carried a similar increase, around 70 percent. Even a single history of blistering sunburn during childhood was associated with a 90 percent higher risk of melanoma compared to never having been sunburned.
Basal Cell Carcinoma
Basal cell carcinoma is the most common skin cancer and the one most directly tied to cumulative sun exposure. It typically appears on the face, nose, ears, and neck. The classic sign is a shiny, translucent bump that looks pearly or slightly see-through. On lighter skin, this bump appears white or pink. On brown and Black skin, it often looks brown or glossy black.
You might notice tiny blood vessels visible on the surface of the bump, though these can be harder to spot on darker skin tones. These bumps tend to bleed easily and then scab over, only to bleed again. Other forms of basal cell carcinoma look quite different: a flat, scaly patch that slowly grows larger over months, or a white, waxy area that resembles a scar and has no clear edge. Some lesions appear as brown, black, or blue spots with a slightly raised, translucent border. The common thread is that none of these go away on their own.
Squamous Cell Carcinoma
Squamous cell carcinoma is the second most common type and tends to appear on areas with heavy sun exposure, particularly the face, ears, lips, and backs of the hands. It often looks like a firm, solid bump (called a 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 topped with a scaly or crusty surface.
One distinguishing feature of squamous cell carcinoma is that it sometimes develops on top of old scars or chronic sores, appearing as a new raised area within damaged skin. On the lips, it may start as a rough, scaly patch that eventually breaks open. Unlike basal cell carcinoma, squamous cell carcinoma carries a real risk of spreading to other parts of the body if left untreated, so early identification matters.
Melanoma
Melanoma is the least common of the three major skin cancers but the most dangerous. It usually looks like a mole that has gone wrong. Dermatologists use the ABCDE framework to describe the warning signs:
- Asymmetry: One half of the spot doesn’t match the other.
- Border: The edges are ragged, notched, or blurred rather than smooth and round. Pigment may bleed into the surrounding skin.
- Color: The spot contains multiple shades, mixing brown, black, and tan with possible areas of white, gray, red, pink, or blue.
- Diameter: Most melanomas are larger than 6 millimeters (about the size of a pencil eraser), though they can start smaller.
- Evolving: The spot has visibly changed in size, shape, or color over recent weeks or months.
Melanoma can appear anywhere on the body, not just sun-exposed areas. It sometimes develops on the soles of the feet, under fingernails, or on skin that rarely sees sunlight. But the strongest statistical link remains between blistering sunburns, particularly in childhood and adolescence, and melanoma risk later in life.
Actinic Keratosis: The Pre-Cancer Stage
Before full skin cancer develops, sun damage often produces precancerous patches called actinic keratoses. These are rough, scaly spots that feel like sandpaper when you run your finger over them. They can be skin-colored, pink, red, brown, or gray, and they tend to appear on the same sun-exposed areas where skin cancer shows up: the face, scalp (especially in people with thinning hair), ears, forearms, and hands.
Actinic keratoses are worth paying attention to because a small percentage of them progress to squamous cell carcinoma if left untreated. They’re essentially a visible warning that your skin has accumulated significant UV damage. If you notice rough, crusty patches that don’t go away after a few weeks, those are worth having evaluated.
How to Tell a Healing Sunburn From Something Concerning
A sunburn follows a predictable timeline. Redness peaks within 24 hours, peeling starts a few days later, and within a week or two the skin looks normal again. Skin cancer doesn’t follow that pattern. The key red flags are persistence and change.
A sore that won’t heal after several weeks, a bump that bleeds and scabs over repeatedly, a scaly patch that keeps growing, a new growth that looks like a mole or scab but doesn’t resolve, or itching and pain around a skin growth are all signs that something beyond normal sun damage is happening. Changes to an existing mole or freckle, particularly getting bigger or shifting color, also warrant attention. The most important question to ask yourself is simple: is this spot doing something different than it was a month or two ago? If the answer is yes, it’s worth having a professional look at it.