Skin cancer is the most common form of cancer, developing when abnormal skin cells grow uncontrollably. The three main types are basal cell carcinoma, squamous cell carcinoma, and melanoma, with melanoma being the most aggressive and potentially deadly. While skin cancer can occur anywhere on the body, it most often appears on areas exposed to the sun, such as the face, neck, ears, arms, and legs. When detected early, most skin cancers are highly treatable, and treatment outcomes are typically very good.

Risk factors for skin cancer include excessive exposure to ultraviolet (UV) radiation from the sun or tanning beds, a history of blistering sunburns, fair skin that burns easily, and having many or atypical moles. A family or personal history of skin cancer, a weakened immune system, and older age also increase risk. Although anyone can develop skin cancer, people with lighter skin tones are at higher risk, while those with darker skin may be diagnosed later, when the disease is more advanced.

Screening for skin cancer involves regular self-examinations to check for new or changing moles, spots, or lesions, as well as periodic full-body skin exams by a healthcare provider. The ABCDE rule—asymmetry, border irregularity, color variation, diameter larger than a pencil eraser, and evolving appearance—helps identify suspicious areas, especially for melanoma. If anything abnormal is found, diagnosis is confirmed through a skin biopsy, in which a small sample of skin is removed and examined under a microscope. Additional imaging or lymph node testing may be needed for more advanced cases. Early detection is key, making routine skin checks and sun protection essential components of skin cancer prevention.