Risk Factors of Skin Cancer

Skin cancer has many potential causes, these include:

1. Studies have show that smoking tobacco and related products can double the risk of skin cancer.^[4][5]
2. Overexposure to UV-radiation may cause skin cancer either via the direct DNA damage or via the indirect DNA damage mechanism. Overexposure (burning) UVA & UVB have both been implicated in causing DNA damage resulting in cancer. Sun exposure between 10AM and 4PM is most intense and therefore most harmful. Natural (sun) & artificial UV exposure (tanning salons) are possibly associated with skin cancer.^{[citation needed]}
   1. UVB rays primarily affect the epidermis causing sunburns, redness, and blistering of the skin when overexposed. The melanin of the epidermis is activated with UVB just as with UVA; however, the effects are longer lasting with pigmentation continuing over 24 hours.
3. Chronic non-healing wounds, especially burns. These are called Marjolin's ulcers based on their appearance, and can develop into squamous cell carcinoma.
4. Genetic predisposition, including "Congenital Melanocytic Nevi Syndrome". CMNS is characterized by the presence of "nevi" or moles of varying size that either appear at or within 6 months of birth. Nevi larger than 20 mm (3/4") in size are at higher risk for becoming cancerous.
5. Human papilloma virus (HPV) is often associated with squamous cell carcinoma of the genital, anal, oral, pharynx, and fingers. It is believed that the HPV vaccine might help to prevent these cancers as well as cervical cancers.
6. Skin cancer is one of the potential dangers of ultraviolet germicidal irradiation.

Skin cancer generally has a 20- to 30-year latency period^{[citation needed]}. Many instances of skin cancer in older individuals today can be traced to behaviours as young adults in the 1970s and early 1980s^{[citation needed]}. Sunburns represented an inconvenient rite of spring or an awkward preliminary stage in the process of acquiring a "healthy" tan. Severe burns were commonplace. Today we know the approach to be reckless. The incidence rates of skin cancer today in persons over 50 years of age reflect that day's popular ignorance