Oral Cancer

Oral squamous cell carcinoma has been described as a disease which primarily affects males in the 6th and 7th decades of life. However, demographic reports suggest increasing incidence rates in younger adults as well as female patients. These trends may be attributed to habits; the use of known carcinogens such as tobacco and alcohol, and adoption of diets poor in antioxidant micronutrients.

Despite the advances made in surgery, radiation and chemotherapy regimens, survival rates for oral cancer patients have remained stagnant over the past three decades. Primary prevention, with emphasis on the control of potential aetiological factors, remains an important strategy against the disease.

Oral cancer: a global problem

Although most of the epidemiological data for oral cancer comes from the Western world, there is enough evidence for its prioritisation as a major global health problem. Over 90% of tumours arising from the oral cavity and oropharynx are squamous cell carcinomas. An estimated 350,000 to 400,000 new cases are diagnosed each year. Approximately 50% of patients survive for 5 years after treatment because of the frequency of metastases, and limitations in screening and curative technology. The prognosis for oral cancer patients is even worse in the so-called developing countries, where patients have limited access to oral health services and typically seek medical attention when the malignancy is at an advanced stage. Also, patients who survive a first encounter with the disease, have up to 20 times higher risk of developing a second cancer, 5 to 10 years after the first lesion.

Risk factors:

Factors with strong association:

Chewing Betel quid chewing
Precancerous oral lesions or conditions
Idiopathic leukoplakia

Other factors:

Diets lacking antioxidants
Genetic factors
Human papilloma viruses
Candida albicans
UV-light (lip, facial skin)
Immune disturbances
Poor oral health

State of the art in oral cancer research

Current treatment strategies are based on the classical view that cancer is composed of a homogenous population of multiplying cells that harbour certain genetic changes solely responsible for their invasive and metastasizing behaviour. This concept overlooks recent breakthrough findings at the front edge of research in human epithelial carcinogenesis, namely that (1) local microenvironment (e.g. tumour-activated fibroblasts) plays a crucial role for the invasive behaviour of tumour cells, and (2) tumours contain heterogeneous cell populations with different self-renewing, surviving and regenerative potential. Development of novel and more efficient oral cancer treatment strategies that take into consideration these factors is thus urgently needed, and for this purpose more basic research is of utmost importance. Our research group is using all its resources on basic research within this purpose.