Overview
Skin cancer is a group of cancers that start in the skin. Common types include basal cell carcinoma, squamous cell carcinoma, and melanoma. Some types grow slowly, while others can spread more quickly to other parts of the body.
Key Symptoms
Warning signs can include a new growth, a spot that looks different from others, a sore that does not heal, or a patch that bleeds, crusts, or itches. A mole may be concerning if it changes in size, shape, or color. Melanoma is often described using the ABCDE warning signs: asymmetry, irregular border, varied color, diameter that is growing, and evolution or change over time.
Causes and Risk Factors
A major cause is damage to skin cells from ultraviolet radiation, mainly from the sun and indoor tanning devices. Risk can also be higher with a history of severe sunburns, many moles, lighter skin that burns easily, older age, weakened immune system, or a personal or family history of skin cancer. However, skin cancer can also occur in people without obvious risk factors.
Who Is Affected
Skin cancer can affect anyone, including children and adults, though some forms are more common in older adults. People with darker skin tones may have a lower risk from UV-related skin cancer, but they can still develop skin cancer and it may be found later. Skin cancer can also develop on the palms, soles, under nails, and other less sun-exposed areas.
Prevention
Prevention focuses on reducing UV exposure. This can include seeking shade, wearing protective clothing, a wide-brimmed hat and sunglasses, and avoiding indoor tanning. Using broad-spectrum sunscreen and reapplying it as directed on the label can also help reduce UV damage.
Diagnosis and Tests
A healthcare professional may examine the skin closely and ask about changes you have noticed. If an area looks suspicious, they may use a dermatoscope and may recommend a skin biopsy, which means taking a small sample to check under a microscope. The biopsy is what confirms whether cancer is present.
Treatment Categories
Treatment depends on the type of skin cancer, its size, depth, location, and whether it has spread. Categories of treatment may include surgery, freezing treatment for certain early lesions, topical medicines for some surface cancers, radiation therapy, and medicines that work throughout the body such as immunotherapy or targeted therapy for some advanced cancers. A specialist can explain which approach fits the exact diagnosis.
When to Seek Medical Care
Arrange medical evaluation if you notice a new or changing mole, a spot that looks different from your other spots, or a sore that does not heal. Also seek care for patches that repeatedly bleed, crust, or become painful. Early evaluation matters even when the area is small or does not hurt.
Questions to Ask a Healthcare Professional
You may want to ask what type of skin change is present, whether a biopsy is needed, and what signs should be monitored at home. If cancer is diagnosed, ask about the type, stage, treatment options, possible side effects, and follow-up skin checks. It can also help to ask how to protect your skin and what changes should prompt urgent review.