Head and neck and lung cancer both have smoking as the main etiologic factor. Even though the prevalence of smokers is decreasing[60], the incidence of the aforementioned tumors is not (Figure 2). Obviously, a proportional increase in the incidences of two separate diseases does not necessarily indicate an etiological relationship but more than that, a shift towards nonsmoking, female gender and adenocarcinoma (compared to squamous cell carcinoma) is arising[61], similar to the example of the esophageal cancer with the exception of the female gender