EPIDEMIOLOGY AND ETIOLOGY
OF ORAL CANCER
ByDr. R.S.CHAITANYA B.D.S
CONTENTS
INTODUCTION EPIDEMIOLOGY ETIOLOGY TOBACCO ALCOHOL DIET AND NUTRITION UV RADIATION FUNGAL INFECTIONS VIRAL INFECTIONS TRAUMA AND DENTAL IRRTATION GENETIC FACTORS
INTRODUCTION
Cancer is one of the major threats to public health in developed and developing countries.
Cancer is second most common cause of death.
Cancer has 4 characteristics Clonality Autonomy Anaplasia Metastasis
CLONALITY
Originates from single cell – proliferates to clone of malignant cell
Autonomy
Growth is not regulated
Anaplasia
Lack of normal coordinated cell differentiation
Metastasis
Capacity for discontinuous growth and dissemination of other parts of the body
ORAL CANCER is classified based on location LIPS TONGUE PALATE CHEEKS GINGIVA FLOOR OF THE MOUTH
According to INTERNATIONAL CLASSIFICATION OF DISEASES (WHO 9th version)
EPIDEMIOLOGY
Oropharyngeal cancer is the eighth most common cancer in worldwide.
The prevalence of oral cancer is particularly high among men.
Incidence rates can vary in men from 1 to 10 cases per 1,00,000 population.
The high incidence rates relate directly to risk behaviors such as smoking, smokeless tobacco, alcohol consumption.
EPIDEMIOLOGY
47%of Indians aged 15years or more use tobacco in one form or other.
EPIDEMIOLOGY
A dose relationship has been shown between the chewing habit and oral cancer.
chewing risk 2 times/day 8.4 6 times/day 17.6 over night 63 Increased risk of oral cancer is seen in those
who only chew as compared to those who only smoke.
ETIOLOGY
TOBACCO ALCOHOL DIET AND NUTRITION UV RADIATION FUNGAL INFECTIONS VIRAL INFECTIONS TRAUMA AND DENTAL IRRTATION GENETIC FACTORS
TOBACCO
Derived from Nicotiana tabacum and Nicotiana rusticum.
CONSTITUENTS: Nicotine Tar Carbon monoxide Nitrogen oxide Hydrogen cyanide and other ciliatoxics Metals Radioactive compounds
TOBACCO CONSTITUENTS
CONSTITUENTS
Nicotine Tar Carbon monoxide
Nitrogen oxides Hydrogen cyanide
Metals Radioactive compounds
EFFECTS
Carcinogen Stains the teeth Myocardial oxygenation,
atherosclerosis Lung damage Deleterious effect on the
cilia of lung Carcinogens Carcinogens
TOBACCO PREPARATIONS
SMOKED TOBACCO
Bidi Chillum Chutta Cigarettes Dhumti Hookah Hookli
SMOKELESS TOBACCO
Khaini Mainpuri tobacco Mawa Mishri Paan Snuff Zarda Gutka Gudaku
BIDI
0.2 to 0.3 gms of sun dreied tobacco flakes are hand rolled.
Nicotine 1.7 to 3.0 mgsTar 45to50mgs
CHILLUM
A 14 cms straight conical clay pipe
Coarsely cut tobacco pieces and a glowing charcoal is kept on top
It is held vertically and to prevent tobacco from entering mouth a pebble stone is introduced
CHUTTA
Cured tobacco is wrapped in a dried tobacco leaf.
It is also called as cigar
CIGARETTES
1 gm of tobacco cured in the sun or artificial heat is covered with a paper
Nicotine 1-1.4mgTar 19-27mg
DHUMTI
Rolled leaf tobacco is used inside a leaf of jack fruit tree
HOOKAH
Tobacco smoke is drawn through the water in the base of hookah which cools and filters the smoke
It is also called water pipe or hobble-bubble
HOOKLI
Clay pipe of 7 to 10 cms long with a mouth piece and a bowl
KHAINI
Powdered sundried tobacco, slaked lime-paste mixture occasionally with used with areca nut
MAINPURI TOBACCO
Tobacco, slaked lime, finely cut areca nut, camphor,cloves
MAWA
Thin shavings of areca nut + tobacco + slaked lime are wrapped in cellophane paper and tied in a shape of a ball
It should be vigorously mixed before consumption
MISHRI
The roasted tobacco is powdered + catechu(a residual extract obtained by soaking the heartwood of acacia catechu
PAAN
Betel leaf+ areca nut+ tobacco +lime+ cinnamon or coconut or cloves or sugar are wrapped in betel leaf
SNUFF
Finely powdered air cured and fire cured tobacco leaves+ areca nut + lime carried in a metal container
It is locally called MUKKU PODUMU
ZARDA
Tobacco leaf is boiled in water along with lime and spices until evaporation. The residual tobacco is dried and coloured with dyes.
GUTKA
Crushed betel nut, tobacco, sweet or savory flavorings
GUDAKHU
Paste of powdered tobacco, molasses, and other ingredients primarily used to clean the teeth.
ALCOHOL
Synergistic effect between tobacco and alcohol.
Heavy drinkers who smoked 20 cigarettes/day– 24 times to get cancer.
Dehydrating effect of alcohol on mucosa increases the potential carcinogens
DIET AND NUTRITION
Vitamin A, C, E &Antioxidant[β-carotene] , copper zinc and
manganeseshows protective effect against
cancer.
Red chilli powder has emerged as a risk factor to cancer
UV LIGHT
Squamous cell carcinoma of vermillion border of lip especially in those who work outdoors
Increased risk in factor individuals
FUNGAL INFECTIONS
Dysplastic lesions[leukoplakia] with candidial infection have greater risk of malignancy
VIRUSES
Human herpes virus1Herpes simplex virus1Human
immunodeficiency virus have been associated with squamous cell carcinoma
TRAUMA AND DENTAL IRRITATION
Continuous irritation from jagged teeth and dentures poor oral hygiene are risk factors for oral cancer
GENETIC FACTORS
Alterations in in many genes have been implicated in development and progression oral cancer
Eg:3p (FHIT) 9P (CDKN2A)
ANY QUERIES……???