Epidemiology of Oral Cancers PDF

PREVENTIVE MEDICINE & INTRODUCTION TO PUBLIC ORAL AND DENTAL HEALTH Epidemiology of Oral Cancers Asst. Prof. Ezgi YÜCEER ÇETİNER School of Dental Medicine Department of Oral and Maxillofacial Surgery [email protected]  Learning Resources Of This Course Are Availa...

PREVENTIVE MEDICINE & INTRODUCTION TO PUBLIC ORAL AND DENTAL HEALTH Epidemiology of Oral Cancers Asst. Prof. Ezgi YÜCEER ÇETİNER School of Dental Medicine Department of Oral and Maxillofacial Surgery [email protected]  Learning Resources Of This Course Are Available From BAU Library: S. S. Hiremath (2016), Textbook of Public Health Dentistry 3rd Ed, Elsevier Joseph John (2018), Textbook of Preventive and Community Dentistry, Public Health Dentistry 3rd Ed CBS Publishers CM Marya (2011), A Textbook of Public Health Dentistry, Jaypee Brothers Medical Publishers Epidemiology of Oral Cancers 17.12.2024  Epidemiological Methods Learning Outcomes 1. To learn about oral cancers epidemiologically, 2. To have opinion about incidence and prevalance of oral cancers, 3. To know oral cancer types and etiological factors, Epidemiology of Oral Cancers 17.12.2024  Epidemiology of Oral Cancers Cancer is characterized by 1. Abnormal growth of cells. 2. Ability to invade adjacent tissues and even distant organs. 3. The eventual death of the affected patient, if the tumor has progressed beyond the stage when it can be successfully removed. The Major Types of Cancers: Carcinomas, Sarcomas, Melanoma, Lymphomas, Leukaemias Epidemiology of Oral Cancers 17.12.2024  Epidemiology of Oral Cancers Oral cancer is one of the ten leading cancers in the world. Oral cancer is described as an indurated, ulcerated lump or sore that may or may not be painful and is often associated with cervical lymph adenopathy. Indurated tongue c. Ulcerated lump (nodule) Ulcerated sore Epidemiology of Oral Cancers 17.12.2024  Epidemiology of Oral Cancers Oral cancers are included in head and neck region cancers. lip, tongue, buccal mucosa, gingiva, floor of mouth roof of the mouth (palate) cheek lining Epidemiology of Oral Cancers 17.12.2024  Epidemiology of Oral Cancers 90 to 95% of all oral cancers are squamous cell carcinomas. The global incidence of oral cancers (the lip and oral cavity) is estimated at 4 cases per 100 000 people.* Oral cancers are among the most prevalent cancers worldwide with 180 000 deaths each year. Oral cancer is more common in men and in older people, and varies strongly by socio- economic condition. In North America and Europe, human papillomavirus infections are responsible for a growing percentage of oral cancers among young people.** * https://www.who.int/news-room/fact-sheets/detail/oral-health **Proposed Resolution on oral health – January 2021 Epidemiology of Oral Cancers 17.12.2024  Epidemiologic Triad of Oral Cancers Agent 1. Biological factors (specific viruses such as EBV and HPV) 2. Chemical factors Time 3. Mechanical factors 4. Nutritional factors Host Factors Environment 1. Age 2. Gender 3. Race 1. Water contaminants 4. Site 2. Air pollution 5. Occupation 3. Geographic variations 6. Smoking and alcohol consumption 4. Solar heat 7. Socioeconomic status 5. Industrialization 8. Immunity Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers 1. Age: Oral cancer incidence increases with age. But age pattern differs in different countries with different risk factors. 2. Gender: Males have higher age specific incidence rates than females for all types of oral cancer. It could be related to higher exposure to risk factors such as alcohol and tobacco consumption. 3. Race: Ethnicity strongly influences prevalence, due to social and cultural practices. Whites develop lip melanoma more frequently than the blacks. Odontogenic tumors and pharyngeal cancers are more common in black races. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers 4. Site: Worldwide the most common intraoral site for oral cancer is tongue and in a number of countries it is a serious public health problem associated with significant morbidity and mortality. More common among man. Use of alcohol and tobacco, HPV virus, chronic irritations are etiological factors. Syphilis is known to have a correlation with carcinoma of tongue. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers 4. Site: Lip cancer is most common on the lower lip. The right and left sides are affected with equal frequency. Chiefly occurs in elderly males. Using tobacco products, heavy alcohol use, being exposed to natural sunlight or artificial sunlight (such as from tanning beds) over long periods of time are etiological factors. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers 4. Site: Buccal Mucosa is the inner lining of the inside of the cheeks and lips. Cancer on the outer cheeks is considered skin cancer. Using tobacco products, heavy alcohol use, chronic irritation as from cheek-biting or sharp tooth or dental prosthesis are etiological factors. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers 4. Site: Gingival cancer constitutes an important group of neoplasms as the diagnosis is always delayed. Because of its close proximity to the teeth and periodontium, the tumour can mimic tooth-related benign inflammatory conditions. It represents less than 10% of diagnosed intraoral carcinoma Chronic irritation is seen to have a role in the development of carcinoma of gingiva. Using tobacco products, particularly chewing tobacco, and regularly drinking too much alcohol are other etiological factors. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers 4. Site: Palate cancer is not a very common lesion. Studies have reported around 9% incidence. Commonly seen with reverse smoking and pipe use. Using tobacco products, drinking too much alcohol are other etiological factors. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers 4. Site: Floor of the mouth cancer constitutes 15% of all intraoral cancers. Floor of the mouth is the horseshoe-shaped area under the tongue. Cancer lesions located at this area are often mistaken for canker sores (aphthous ulcers). Using tobacco products, chewing tobacco, using pipe and drinking too much alcohol are etiological factors. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers 5. Occupation: Textile workers show an increase in oral cancer. Exposing carcinogenic chemicals. Male leather workers show an increase in cancer of buccal cavity, larynx and pharynx. 6. Smoking : Smoking is the most important etiological factor of oral cancers!!! Cigarette contains thousands of chemical compounds. Many of these compounds (60 or more) are pharmacologically active, toxic, mutagenic and carcinogenic. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers Tobacco cause epigenetic alteration of oral epithelial cells, inhibit multiple systemic immune functions of the host, and its toxic metabolites can cause oxidative stress on tissues and induce oral squamous cell carcinoma. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers There is a clear dose-response relationship between tobacco use and the risk of oral cancer or potentially malignant oral disease. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers Oral cancer accounts for over 140 000 deaths annually across the world. Over 300 000 people are diagnosed with oral cancer each year. Tobacco use, alcohol consumption, and poor diet together possibly explain about 90% of head and neck cancers. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers Smoking cigarettes, cigars and, loose tobacco in pipes is the predominant form of use in Western countries and is increasing in developing countries. Chewed tobacco, along with betel and areca nut, is more common in Asia, and areca nut alone in the Pacific islands. Tobacco use among the youth is higher in developing countries, while it is declining in more developed economies. This trend could potentially shift the mean age of presentation of oral cancers (currently 60 years of age) earlier. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers Nicotine: Nicotine is the pharmacological agent in the tobacco that causes addiction among smokers. The addictive effect of nicotine is linked to its capacity to trigger the release of dopamine—a chemical in the brain that is associated with the feelings of pleasure. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers With prolonged exposure to nicotine causes the contraction of vascular endothelial cells, reducing blood flow, reduces the immune cells and gingival crevicular fluid (GCF), reduce the host immunity. Nicotine is not classified as a carcinogen but it enables the formation of tobacco specific nitrosamines, which are strong carcinogens. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers Nitrosamines: carcinogenic organic substances that formed by a reaction between nitrates or nitrites and certain amines. They exist in low levels in our water and foods, including meat, vegetables, and dairy products. Nitrosamines come from chemical reactions and can form in drugs during manufacturing. It is abundant specially in processed foods, tobacco and alcohols, fish, and fish byproducts, and also in meat and cheese products preserved with nitrite pickling salt. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers Tar: Tar” describes the particulate matter inhaled when the smoker draws on a lighted cigarette. Each particle is composed of nitrogen, oxygen, hydrogen, carbon dioxide, carbon monoxide and two major classes of tumor initiators: polycyclic aromatic hydrocarbons (Benzopyrene) and tobacco-specific nitrosamines. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers Carbon Monoxide (CO): Carbon monoxide is a colorless, odorless, poisonous gas. Carbon monoxide interferes with uptake of oxygen in the lungs and with its release from the blood to the tissues that need it. When carbon monoxide is inhaled it combines with the hemoglobin in the blood to form carboxylhemoglobin. As carbon monoxide has a chemical affinity for hemoglobin over 200 times greater than that of oxygen, it binds preferentially with hemoglobin, thereby reducing the amount of oxygenated blood circulated to body organs and tissues. Thus, the oxygen transportation in the body is impaired. Epidemiology of Oral Cancers 17.12.2024  Host Factors of Oral Cancers Radioactive Compounds: The radioactive compounds found in highest concentration in cigarette smoke are polonium-210 and potassium-40. Other radioactive compounds present include radium-226, radium-228 and thorium- 228. Radioactive compounds are well established as carcinogens. Epidemiology of Oral Cancers 17.12.2024  Agent Factors of Oral Cancers Biological: (a) Virus (HIV, HPV, EBV, HSV), (b) Fungus (Candida). Kaposi sarcoma Candidiasis could promote tumor occurence by producing compounds such as nitrosamines, promotes cancer through a proinflammatory response or induction of Th17 (T helper 17 cells) response (excess inflammation from Th17 cells could lead to carcinogenesis). Epidemiology of Oral Cancers 17.12.2024  Agent Factors of Oral Cancers Chemical: Arsenic, dyes, nickel, aromatic amines, chromium. Mechanical: Sharp tooth, any other source of chronic irritation like ill fitting dentures, chronic sores from jagged teeth, etc. Nutritional agents: Precarcinogens in food (saccharin, aflatoxin), increased consumption of fat, deficiency of folic acid, protein deficiency, increased consumption of red chilly powder, decrease in copper, zinc, vegetables, vitamins E and C. Epidemiology of Oral Cancers 17.12.2024  Environmental Factors of Oral Cancers Water contaminants: It includes some organic pollutants like chloroform. Air pollution: Air pollution caused by the release of a number of gases from the automobiles and factories, e.g. carbon dioxide. Solar heat: Prolonged exposure to sunlight causes melanoma. Industrialization: The release of various toxins by the industries contaminates water and air, which may lead to cancer. Epidemiology of Oral Cancers 17.12.2024  Environmental Factors of Oral Cancers Geographic variations: Oral cancer shows marked geographic differences in occurrence. The incidence rate of oral cancer varies widely from one country to another, and from region to region within countries. The oral cancer incidence in lower/middle income countries or developing countries tends to be higher than that of developed countries. In Netherlands, buccal mucosa is most commonly affected and is more often seen in males. In Switzerland, lip, tongues are the sites most affected and is often seen in males. In Canadian Eskimos, cancer of salivary gland is more common. In Srikakulam, and Visakapatnam, palatal cancer is most common. Epidemiology of Oral Cancers 17.12.2024 THANK YOU..