The incidence of squamous cell carcinoma continues to rise around the world. A recent study estimated that there are between 180,000 and 400,000 cases of SCC in the United States in 2013.  Risk factors for squamous cell carcinoma varies with age, gender, race, geography, and genetics. The incidence of SCC increases with age and the peak incidence is usually around 60 years old. Males are affected with SCC at a ratio of 2:1 in comparison to females. Caucasians are more likely to be affected, especially those with fair Celtic skin and chronically exposed to UV radiation. Squamous cell carcinoma of the skin is the most common among all sites of the body. Solid organ transplant recipients (heart, lung, liver, pancreas, among others) are also at a heightened risk of developing aggressive, high-risk SCC. There are also a few rare congenital diseases predisposed to cutaneous malignancy. In certain geographic locations, exposure to arsenic in well water or from industrial sources may significantly increase the risk of SCC. 
Acne is often present. Acne conglobata is a particularly severe form of acne that can develop during steroid abuse or even after the drug has been discontinued. Infections are a common side effect of steroid abuse because of needle sharing and unsanitary techniques used when injecting the drugs into the skin. These are similar risks to IV drug abusers with increased potential to acquire blood-borne infections such as hepatitis and HIV/AIDS . Skin abscesses may occur at injection sites and may spread to other organs of the body. Endocarditis or an infection of the heart valves is not uncommon.