Basal-cell carcinoma
In the United States approximately 3 out of 10 caucasians develop a basal-cell carcinoma during their lifetime. This tumor accounts for approximately 70% of non-melanoma skin cancers. In 80 percent of all cases, basal-cell carcinoma affects the skin of head and neck. Furthermore, there appears to be an increase in the incidence of basal-cell cancer of the trunk in recent years.
Infectious causes of cancer
Worldwide in 2015, the most common causes of cancer death were lung cancer (1.6 million deaths), liver cancer (745,000 deaths), and stomach cancer (723,000 deaths). Lung cancer is largely due to non-infectious causes, such as tobacco smoke. However, liver and stomach cancer are primarily due to infectious causes. Liver cancer is largely caused by infectious hepatitis B virus (HBV) plus hepatitis C virus (HBC) and stomach cancer is largely caused by "Helicobacter pylori" bacteria. World-wide, the estimated number of people chronically infected with HBV and/or HCV is ~325 million. Over half of the world's population is colonized with "H. pylori" and it is estimated that "H. pylori"-positive patients have a 1-2% risk of developing distal gastric cancer.