Epidemiology and risk factors

Abstract

OBJECTIVES The aim of the present review is to update the dentist on the current knowledge regarding mouth cancer, in particular on its epidemiological aspects, in terms of frequency and distribution, and on modifiable and non-modifiable risk factors. MATERIALS AND METHODS We queried he most important biomedical databases (PubMed, Embase) and Google Scholar in search of articles relevant to the objectives of the article. The full texts of these articles were ob-tained. The information acquired was further integrated with texts and data already available to the authors. RESULTS Awareness of oral cancer among the general population in Italy, as in many countries around the world, is not satisfactory. Which probably negatively affects primary prevention, as well as the timeliness of diagnosis, a key factor in the success of treatment disease in terms of survival and quality of life. However, oral cancer is far from rare, being one of the 20 most frequent cancers in the world, with approximately 350,000 new cases in 2018, two thirds of which among male pa-tients. It is also affected by high mortality, since the 5-year survival is approximately of 50%. This is also true in Italy, as shown by the most recent data indicating that the cumulative risk for cancers of the air-digestive tract is equal to 46 in males, which means that it is sufficient to follow 46 Italian males from 0 to 84 years of age to find one that develops a cancer. Although this is a multifactorial disease, about whose pathogene sis we still have to learn a lot, there are subjects at greater risk. Among them certainly smokers, for whom a link between the num ber of cigarettes and the possibility of developing cancer has been established for years. However, it has recently been shown that this risk exists for those who smoke even only a few cigarettes a day (1-3), especially if they have been doing it for many years. Likewise, second-hand smoke is also a recognized risk factor for those exposed for long enough. In addition to smoking, the other major risk behaviour is alcohol consumption, an independent factor which, when associated with smoking, has a more than multiplicative effect on the possibility of developing cancer. Other factors associated with the disease include Human Papilloma Virus infection, the health and hygiene of the oral cavity, socio-economic conditions, dietary habits and familiarity. It is possible that these factors play a role in those subjects, who developed cancer, despite lack of exposure to smoke and alcohol (about one fifth of the total). Another group of individuals at greater risk of getting oral cancer are those suffering from a group of mouth diseases defined potentially malignant disorders, a term that replaced the expression of premalignant lesions. This group is quite heterogeneous and includes conditions very different for aetiology, frequency, nature and clinical history, such as leukoplakia, lichen planus, erythroplakia, oral lupus, graft versus host disease of the mouth, actinic cheilitis and other less frequent diseases in our country such as submucosal fibrosis. For all those conditions we do not have treatments that can eliminate or even significantly reduce the risk of oral cancer for the affected patients. CONCLUSIONS The most important tool available to the clinician for the management of patients who, due to modifiable or non-modifiable factors, are at risk of getting mouth cancer, is careful follow-up. The primary purpose of which is to intercept the onset of the disease as soon as possible, in order to guarantee the best chance of survival and the best possible quality of life the affected patient. CLINICAL SIGNIFICANCE Oral cancer is a disease that the dental team must know and recognize, to be able to offer to patients a sound information about the disease and its main risk factors, and to establish correct follow-up in subjects at risk.