Oral cancer; the evidence for sexual transmission.

The incidence of oral cancer amongst young adults is increasing in many European and high incidence countries. Most oral cancer is aetiologically linked to the use of tobacco and/or alcohol but nearly two decades ago, we produced the first evidence for the presence of viral nucleic acids in oral squamous cell carcinoma (OSCC) tissues, hypothesising that there may be a viral involvement in at least some OSCC. Subsequently, human papillomaviruses (HPV) in particular have been implicated in OSCC. Antibody responses to HPV are seen and HPV-DNA detected in tumours by us and many others, the virus being mainly HPV-16, the genotype associated with ano-genital cancer. Recent studies have indicated that HPV may be aetiologically important particularly in some types of oropharyngeal cancer, at least in tonsillar carcinogenesis, and may represent an alternative pathway in carcinogenesis to the established factors of tobacco and alcohol. Studies of patients with OSCC have suggested possible sexual transmission of HPV.