HEREDITARY AND ENVIRONMENTAL RISK-FACTORS - CLINICAL AND LABORATORY RISK MARKERS FOR HEAD AND NECK, ESPECIALLY ORAL, CANCER AND PRECANCER

The continuing high incidence and mortality of squamous cell carcinoma of the upper aerodigestive tract in South Asia, parts of France and c entral Europe, together with a rising incidence and mortality from a l ower base elsewhere in the Western world, stimulates continuing resear ch on risk factors and risk markers. Tobaccos (smoked and smokeless), heavy alcohol consumption, and areca nut remain the dominant risk fact ors, with confirmation of the protective effects of diets rich in anti oxidants. There is emerging evidence of a small, but real, risk associ ated with occupational and other air pollution, and with family, part of which may be hereditary. Markers in peripheral blood and saliva are underexploited. Clinical staging and histological grading methods con tinue to be refined, with improved prognostic value, much aided by new er and simpler methods for estimating cell proliferation and apoptosis . Data on the significance of viral genes are still inadequate, but th ere is good progress describing the epidemiology of chromosomal abnorm alities and abberations of a growing list of oncogenes and tumour supp ressor genes. Unfortunately, as yet, these have only limited longitudi nal or prognostic data.