<unk>  is a common skin cancer and occurs mainly in fair-skinned patients with a family history of this cancer. Sunlight is a factor in about two-thirds of these cancers; therefore, doctors recommend sunscreens with at least SPF 30. However, a Cochrane review examining the effect of solar protection (sunscreen only) in preventing the development of<unk>  or cutaneous squamous<unk><unk>  found that there was insufficient evidence to demonstrate whether sunscreen was effective for the prevention of either of these keratinocyte-derived cancers. The review did ultimately state that the certainty of these results was low, so future evidence could very well alter this conclusion. One-third occur in non-sun-exposed areas; thus, the pathogenesis is more complex than UV exposure as the cause. The use of a chemotherapeutic agent such as 5-Fluorouracil or imiquimod can prevent the development of skin cancer. It is usually recommended to individuals with extensive sun damage, history of multiple skin cancers, or rudimentary forms of cancer (i.e., solar keratosis). It is often repeated every 2 to 3 years to further decrease the risk of skin cancer.
Basal-cell carcinoma
Melanoma
Lymphoepithelioma
Seborrheic keratosis
Trichoepithelioma
Psoriasis
Angiokeratoma
Milium (dermatology)