Skin cancer is the most common type of cancer diagnosed globally. It commonly develops in sun-exposed areas of skin. Skin cancers can be found on any location of the body but are most commonly diagnosed on the head and neck (ie, areas of chronic sun exposure).
The incidence of skin cancer is highest among people who spend significant amounts of time outdoors for work or recreation and is inversely related to the amount of melanin skin pigmentation in the individual; people who have light skin are most susceptible.
Worldwide, more than 1.5 million new cases of all types of skin cancer were diagnosed in 2022 (1). An estimated 330,000 of these were new diagnoses of melanoma, out of which there were 60,000 fatalities. In the United States, an estimated 107,240 incident cases of melanoma and 8,340 deaths (due to invasive melanoma) are expected in 2025 (2). Nonmelanoma skin cancer estimates are not as frequently recorded or reported in most cancer registries. In one 2019 nationwide study in the United States, incidences per 100,000 people were 525 for basal cell carcinoma, 262 for squamous cell carcinoma, and 17 for melanoma (3).
In the United States, skin cancer accounts for more cancer diagnoses than all other cancers combined. At least 1 in 5 Americans are expected to develop skin cancer by age 70 (4).
The most common forms of skin cancer are:
Basal cell carcinoma (approximately 80%) (5)
In addition, several less common forms of skin cancer exist including:
Paget disease of the breast or extramammary Paget disease (usually in the groin or near the anus)
Tumors of the adnexa
Cutaneous T-cell lymphoma (mycosis fungoides)
Squamous cell carcinoma in situ (formerly called Bowen disease) is a superficial squamous cell carcinoma limited to the epidermis. Keratoacanthoma may be a well-differentiated form of squamous cell carcinoma.
Initially, skin cancers are often asymptomatic. The most frequent presentation is an irregular red or pigmented lesion that does not go away. Any lesion that appears to be enlarging, painful, or bleeding should be considered for biopsy or the patient should be referred to a dermatologist. If identified and treated early, most skin cancers are curable.
Pearls & Pitfalls
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General references
1. International Agency for Research on Cancer. Skin cancer. Accessed November 13, 2025.
2. Siegel RL, Kratzer TB, Giaquinto AN, et al. Cancer statistics, 2025. CA Cancer J Clin. 2025;75(1):10-45. doi:10.3322/caac.21871
3. Aggarwal P, Knabel P, Fleischer AB Jr. United States burden of melanoma and non-melanoma skin cancer from 1990 to 2019. J Am Acad Dermatol. 85(2):388-395, 2021. doi: 10.1016/j.jaad.2021.03.109
4. The Skin Cancer Foundation:. Skin Cancer Facts & Statistics. Accessed November 13, 2025.
5. American Cancer Society. Key Statistics for Basal and Squamous Cell Skin Cancers. October 31, 2023. Accessed November 10, 2025.
Prevention of Skin Cancer
Because many skin cancers are likely associated with ultraviolet (UV) radiation exposure, a number of preventive measures are recommended to limit the effects of sun exposure.
Sun avoidance: Seeking shade, minimizing outdoor activities between 10 AM and 4 PM (when the sun's rays are strongest), and avoiding sunbathing and the use of tanning beds
Use of protective clothing: Long-sleeved shirts, pants, and broad-brimmed hats
Use of sunscreen: At least sun protection factor (SPF) 30 with broad-spectrum UVA/UVB protection, used as directed (ie, reapplied every 2 hours and after swimming or sweating); should not be used to prolong sun exposure
Protection against sun exposure decreases the incidence of cancer occurrence in both nonmelanoma skin cancers (basal cell carcinoma and squamous cell carcinoma) and melanoma (1).
See also Overview of Effects of Sunlight.
Screening
Some professional organizations support clinical examination and self-examination to screen for skin cancer; however, the US Preventive Services Task Force has not found sufficient evidence to do so for the general population and provides a summary of recommendations for screening for skin cancer (2) and counseling about skin cancer (3).
High-risk patients, such as those taking immunosuppressants, those with a personal or strong family history of skin cancer, or those with a known, increased susceptibility to skin cancer because of specific genetic mutations or environmental exposures, should be considered for routine skin cancer surveillance (2).
A personal history of multiple atypical nevi (moles) should raise clinical suspicion for melanoma and should prompt screening. See also Atypical Nevi.
Prevention references
1. Green A, Williams G, Neale R, et al. Daily sunscreen application and betacarotene supplementation in prevention of basal-cell and squamous-cell carcinomas of the skin: a randomised controlled trial. Lancet 354(9180):723-729, 1999. doi: 10.1016/S0140-6736(98)12168-2
2. US Preventive Services Task Force. Skin Cancer. Screening; Final Recommendation Statement. April 28, 2023. Accessed October 29, 2025.
3. U.S. Preventive Service Task Force. Skin Cancer Prevention. Behavioral Counseling. March 20, 2018. Accessed November 13, 2025.
