Freud, Sex and Oral Cancer

Imad Abu El-Naaj , Faculty of medicine , Bar Ilan University , Tiberias, Israel

Oral cancer is the sixth most prevalent cancer worldwide, when summarizing the global incidence rates of head and neck cancer, annually, approximately 620,000 patients are diagnosed with cancer of oral cavity, naso-pharynx, oro-pharynx, and larynx.  Oral cancer ranked third in the developing countries and eighth in the developed countries, while, the high-risk areas and countries include France (Bas-Rhine region), Hungary (Vasi region), India, Brazil, China (Hong Kong), and Philippines.  According to the world statistics, approximately 267,000 new oral cancer cases were diagnosed and about 128,000 patients died of this cancer in the year 2000.

Over 80% of these lesions are squamous cell carcinoma (SCC). Clinical presentation of oral cancer is highly variable. On clinical examination, oral SCC lesions may be preceded by mucosal alterations with histologically detectable dysplastic changes. All head and neck carcinomas tend to be diagnosed late because there is no pain until the late stages. Thus, the overall survival is only 40–50%.

The most important risk factor of head and neck cancer worldwide is smoking, with alcohol coming second. The risk is dose-dependent and the simultaneous use of both increases the risk many-fold, explaining some 75–85% of the cases.

In 1983, Stina Syrjänen proposed an evidence on HPV (human papilloma virus) as an etiological factor in oral SCC, by analyzing the presence of HPV antigens in 40 oral carcinomas using immunohistochemistry (IHC). Out of 40 lesions, 16 (40%) showed HPV-suggestive changes on light microscopy, and of those, 8/16 expressed HPV structural proteins.  A few years later, these biopsies were examined for the presence of HPV DNA using ISH and PCR, and 12/40 disclosed the presence of HPV11, 16 or 18 DNA.

Interestingly, patients with HPV 16-positive tumors seem to have a better overall- and disease-specific survival, as compared with the HPV-negative patients.