The epidemiology of oral cancer. Numbers. Causation. Prevention.

1. EPIDEMIOLOGY
OF
Dept. Of Public Health Dentistry
PCDS & RC

2. LEARNING OBJECTIVES
▸ Global scenario of oral cancer
▸ Spectrum of oral cancer in India
▸ Distribution and Measurement of Oral Cancer
▸ Trends
▸ Etiology and risk factors
▸ Classification of oral cancers
▸ Clinical presentations
▸ Diagnosis
▸ Treatment
▸ Prevention and Control
▸ Role of dentist

3. Oral Cancer, Also Known As Mouth
Cancer, Is A Type Of Head And Neck
Cancer And Is Any Cancerous Tissue
Growth Located In The Oral Cavity.
Wikipedia

4. AN INTERMEDIATE CLINICAL STATE WITH
INCREASED CANCER RISK, WHICH CAN BE
RECOGNIZED AND TREATED, OBVIOUSLY
WITH A MUCH BETTER PROGNOSIS THAN
A FULL BLOWN MALIGNANCY.
ORAL PRECANCER

5. DEFINITION
4 CHARACTERISTICS
▸ CLONALITY : Cancer originates from genetic changes in single
cell which proliferates to form a clone of malignant cells.
▸ AUTONOMY : Growth is not properly regulated by the normal
biochemical and physical influences in environment.
▸ ANAPLASIA : There is a lack of normal, co-ordinated cell
differentiation.
▸ METASTASIS : Cancer cells develop capacity for discontinuous
growth and dissemination to other parts of body.

6. GLOBAL SCENARIO : CANCER
▸ Developed countries : SECOND Most common cause of death.
▸ Acc. to WHO report 2004- cancer accounted for 7.1 million deaths.
▸ Highest among Men.

7. TEXT
▸ 6th Most common
cause of cancer related
death.
▸ 1-10 cases per 1,00,000
population.
▸ TONGUE - most
common intra oral site.
•Denmark, France, Germany,
•Scotland, central and eastern
Europe
GLOBAL SCENARIO : ORAL CANCER

8. TEXTSPECTRUM OF ORAL CANCER IN INDIA
▸ HIGHEST incidence of oral
cancer in world.
▸ 12% of all cancers in Men.
▸ 8% of all cancers in
Women.
▸ Half million cases of
cancer added every year.
▸ Of these 1/3rd is Oral
Cancer = 5 lakh cases at a
given time.
▸ Linked with tobacco habit.

9. HEAD AND NECK CANCERS

10. ICD-9 : 140-149
ICD-10 : C00-C14
International Classification of
Disease system of WHO.

11. EPIDEMIOLOGICAL TRIAD OF ORAL CANCER

12. 1. Gender : Males > Women
2. Age
mean age of occurrence :
50-70years
3. Race
Increased incidence in chinese
ancestry, American blacks.
4. Genetic characteristics
genetic mutations 3q, 4q, 6q, 8q,
11q, 18q in asso with tobacco use.
5. Socio economic status
affects those with Lower SES.
6. Education
lower education attainment -
greater risk.
7. Occupation
exposure to carcinogens - leather
industry, oil, textiles, coal mines.
8. Lifestyle
vitamin deficiencies, Tobacco
users - greater risk

13. 1. BIOLOGICAL FACTORS
human papilloma virus - associated with
cancers
2. CHEMICAL
Habit of tobacco with lime
bhopal gas tragedy - exposure to
methyl isocyanate (carcinogen)
3. MECHANICAL
chronic irritation of mucosa - sharp
cusps of teeth, ill fitting dentures.

14. 1. UV RADIATION
- Solar radiation is
carcinogenic - skin cancers
(basal cell carcinoma, SCC).
- Lower lip affected due to
sunlight exposure.

15. TEXT DISTRIBUTION OF ORAL CANCER
▸ Incidence increases with age.
▸ With advancing age, certain sequenced alterations in
biochemical/biophysical processes of aging cells with a
particular aging predisposition undergo and accumulate
mutations, resulting in carcinogenic transformations.
▸ 96% oral cancer is diagnosed in persons >40years.
▸ 50% oral cancer is diagnosed in persons >65years.
▸ Average age at time of diagnosis : 63 years.
▸ Recent evidence : frequent occurrence in younger
persons.
AGE DISTRIBUTION

16. TEXT DISTRIBUTION OF ORAL CANCER
▸ In industrialized countries MEN are affected twice
as women. (Due to high risk factors- tobacco,
alcohol, sunlight.)
▸ Incidence of Tongue cancer : Women > Men
▸ Ratio of Male to Female diagnosed with oral
cancer is 2:1.
GENDER DISTRIBUTION

17. TEXT DISTRIBUTION OF ORAL CANCER
▸ Strong influences due to social and cultural
practices.
▸ Continuation by immigrants from high- incidence
regions to other parts results in high cancer
incidence in immigrant communities.
▸ Black Americans experience more pharyngeal
cancers than their white counterparts.
ETHNIC VARIATIONS

18. DISTRIBUTION OF ORAL CANCER
▸ Lip cancer - more common in fair skinned races,
particularly in rural areas and in men who work
outdoors.
▸ Intraoral cancers in Western countries - Lateral
borders of tongue and floor of mouth.
▸ Hard palate and dorsum of tongue - lowest risk.
▸ In high risk areas of South Asia - Buccal,
Retromolar and commissural mucosae are most
prone.
SITE DISTRIBUTION

19. TRENDS
▸ In urban parts of high incidence regions, such as Mumbai,
there may be fall in oral cancer which could be attributed
to change from pan chewing and bidi smoking to smoking
of manufactured cigarettes.
▸ The rising trend of tongue cancer in young men in western
countries is thought to be due to marked increase in
alcohol consumption, combined with smokeless tobacco
products.

20. ETIOLOGY AND RISK FACTORS

21. Multifactorial
Etiology ESTABLISHED RISK FACTORS
1. Smoking Tobacco
2. Chewing Tobacco
3. Chewing betel quid (paan)
4. Heavy consumption of alcohol
5. Presence of a potentially malignant oral lesion
OTHER CONTRIBUTORY OR PREDISPOSING FACTORS
1. Dietary deficiency (vit A, C, E, iron)
2. Familial or genetic predisposition
3. Virus infections (Human papilloma virus)
4. Sunlight (lip cancer)
5. Candida albicans infection
6. Immune deficiency
7. Environmental exposure
8. Dental trauma

22. TOBACCO
HISTORY :
Christopher Columbus - a gift of strange dry
leaves.
India - pipe called tobago was placed in
nostrils
1st Commercial plantation in USA - Virginia
1612.
19-20th century : dental snuff was said to
relieve toothache, bleeding gums, preserve
and whiten teeth and prevent decay.
40-45% of smokers (Males) - Bidi, In urban areas -
Cigarretes.
9% in rural areas - chewing tobacco
Orissa HIGHEST.
31% of tobacco grown in India is used for manufacture of
cigarretes.
“REVERSE SMOKING” - Females in AP - Air is supplied to
burning zone through unlighted end of cigarrete.

23. TOBACCO PREPARATIONS PLANT - NICOTIANA
SMOKED TOBACCO
1. Bidi : 0.2-0.3gm of sundried tobacco flakes
are hand rolled in a rectangular piece of
temburni/tendu. Nicotine content : 1.7-3mg,
tar : 45-50mg.
2. Chillum : long conical clay pipe used for
smoking tobacco.
3. Chutta/Cigar : cylindrical coarsest prepared
cheroot with cured tobacco.
4. Cigarretes : 1gm of cured tobacco covered
with paper. Flavored, aromatic. Nicotine :
1-1.4mg, Tar : 19-27mg. Filter Length=
12mm
5. Dhumti : Rolled leaf tobacco is used inside
leaf of jackfruit tree. Used for Reverse
smoking.
6. Hookah : (water pipe) Used in places with
strong Moghul cultural influence.
7. Hookli : clay pipe
SMOKELESS TOBACCO
1. Khaini :powdered sundried tobacco, slaked
lime -paste mixture used with arecanut.
2. Mainpuri tobacco : tobacco, slaked lime,
arecanut, camphor, cloves. Prevalent in U.P.
High prevalence of oral cancer, leukoplakia.
3. Mawa: thin shavings of arecanut, tobacco,
slaked lime wrapped in cellophane paper.
4. Mishri : roasting tobacco on hot metal plate.
Used with catechu.
5. Paan : betel leaf.
6. Snuff
7. Zarda
8. Gutka
9. Pan Masala
10. Gudakhu

24. CONSTITUENTS OF TOBACCO
‣ NICOTINE : most toxic of all poisons. Addictive effect is due to its
capacity to trigger release of Dopamine - asso. with feeling of
pleasure. It enables formation of tobacco specific Nitrosamines -
potent carcinogens.
‣ TAR : The particulate matter inhaled while smoking. Sticky brown
substance. Benzopyrene -a carcinogen is found in tar.
‣ CARBON MONOXIDE : interferes with uptake of oxygen by lungs.
Devt. of Coronary heart disease.
‣ NITROGEN OXIDES : lung damage - emphysema
‣ HYDROGEN CYANIDE : deleterious effect on lungs
‣ METALS : Ni, As. Cd, Cr, Pb - asso. with cancer
‣ RADIOACTIVE COMPOUNDS : Polonium-210, Potassium-40 :
Carcinogens

25. HEALTH CONSEQUENCES OF TOBACCO
‣ Major contributor to oral disease. Slows wound healing,
promoted periodontal disease, halitosis, oral infections.
‣ Cancer of oral cavity, pharynx, larynx, esophagus, stomach,
uterine cervix, lungs.
‣ Cardiovascular disease
‣ Chronic obstructive lung disease, emphysema, chronic bronchitis.
‣ Second hand smoke - Worsening of asthma, poor lung funtion.
‣ Major risk factor for TB
‣ Pregnant women exposed to smoke may deliver lower weight
babies, stillborn babies, congenital cleft lip and palate,
‣ Men - reduced fertility and sexual impotence.

26. FAMILIAL AND GENETIC PREDISPOSITION
IMMUNOSUPPRESSION
‣ Polymorphisms in GST genes, CYP genes,
Cytochrome P-450 system.
‣ Genetic predisposition is small.
‣ Individuals with HIV/AIDS are at higher risk of
neoplasms
‣ Kaposi’s Sarcoma
‣ Lymphomas
‣ Oral hairy leukoplakia

27. OCCUPATION AND RISK OF ORAL CANCER
‣ EFFECT OF SOLAR RADIATION
‣ Outdoor workers are at greater risk for LIP cancer.
‣ Due to long term exposure to UV light
‣ EFFECT OF ATMOSPHERIC POLLUTION
‣ Mean sulphur dioxide and smoke concentration are
positively correlated with SCC of larynx.
‣ Fossil-fuel combustion - pharyngeal cancers

28. VIRUSES AND ORAL CANCER
‣ 15% of human cancers may have etiological relationship
to viral infections.
‣ Human Papilloma Viruses (HPV) - high oncogenic risk.
‣ HPV-6,11,16 - Papilloma, Leukoplakia
‣ HPV- 16, 18, 6, 2, 57 - SCC.
‣ Ebstein Barr Virus (EBV) - Nasopharyngeal CA,
Lymphomas
‣ HHV-8: Kaposi’s Sarcoma.
‣ DNA oncogenic virus is SV40.

29. CLASSIFICATION OF
ORAL CANCER

30. TEXTACCORDING TO SITE
▸ ALVEOBUCCAL SULCUS : Most common. More in Men.
Asso. with quid placement.
▸ LIP : in elderly men. Lower lip>upper lip
▸ TONGUE : 25-50% of all oral cancers.
▸ GINGIVA : Chronic irritation is a suspected cause.
▸ FLOOR OF MOUTH : 15% of oral cancers. Pipe/cigar
smoking.
▸ PALATE : Not very common. Seen with reverse smoking.

31. TEXT BENIGN AND MALIGNANT
•Benign tumours of epithelial origin
•Papilloma
•Squamous acanthoma
•Keratoacanthoma
•Pigmented cellular naevus
•Premalignant lesions & conditions
of epithelial origin
•Leucoplakia
•Erythroplakia
•Oral submucous fibrosis
•Lichen planus
•Malignant tumors of epithelial
tissue origin
•Basal cell carcinoma
•Adenoid squamous cell
carcinoma
•Malignant melanoma
‣ Begin tumors of connective
tissue origin
•Fibroma
•Peripheral ossifying fibroma
•Haemangioma
•Lymphangioma
•Chondroma
•Osteoma
‣ Malignant tumors of
connective tissue origin
• Fibrosarcoma
• Chondrosarcoma
• Ewing's sarcoma
• Osteosarcoma
• Malignant lymphoma
• Hodgkin's disease

32. TEXT CLINICAL PRESENTATIONS OF ORAL CANCER
▸ More than 90% of oral cancers are Squamous Cell CA.
▸ 10% are salivary gland tumors, lymphomas, sarcoma etc.
‣ ULCER : any ulcer of mucosa, that fails to heal
within 2 weeks.
‣ INDURATION
‣ FUNGATION : growth of tissues to produce
elevated cauliflower surface or lump.
‣ FIXATION of mucosa to underlying tissues.
‣ TOOTH mobility with no apparent reason.
‣ PAIN/PARAESTHESIA with no apparent cause.
‣ DYSPHAGIA
‣ WHITE/RED PATCHES of mucosa
‣ LYMPHADENOPATHY

33. TEXT PRECANCEROUS
▸ PRECANCEROUS LESIONS :
▸ Leukoplakia
▸ Erythroplakia
▸ Smoker’s Palate
▸ PRECANCEROUS CONDITIONS :
▸ OSMF
▸ Lichen Planus

34. TNM STAGING

35. DIAGNOSIS OF ORAL CANCER‣ BIOPSY
‣ EXFOLIATIVE CYTOLOGY
‣ TOLUIDINE BLUE STAINING
‣ COMPUTED TOMOGRAPHY SCAN
‣ ULTRASOUND
‣ MAGNETIC RESONANCE IMAGING

36. TREATMENT OF ORAL CANCER
‣ PREVENTION AND CONTROL OF CANCER -
HEALTH EDUCATION
‣ SECONDARY PREVENTION
‣ TERTIARY PREVENTION

37. TEXT PRIMARY PREVENTION
▸ Mainly focuses on Modifying Habits.
▸ Educational programs, warning signals,
importance of checkup, oral hygiene, diet etc.
▸ 3 well known approaches :
▸ REGULATORY APPROACH
▸ SERVICE APPROACH
▸ EDUCATIONAL APPROACH

38. TEXT
▸ Cigarette Act 1975 has made it necessary to print
warnings on cigarette packets.
▸ National Cancer Control Program 1985
▸ 2003 - ‘Cigarette and other Tobacco products Act’ -
prohibit advertisement for regulation of trade.
REGULATORY APPROACH
SERVICE APPROACH
▸ Active search for disease among apparently healthy
people is a fundamental aspect of prevention.
▸ This is embodied in screening.

39. TEXT EDUCATIONAL APPROACH
▸ Hold a vital role in prevention and early detection of
cases.
▸ Screening and examination are elements of dental
practice routine.
▸ Dentists are in ideal position to counsel patients.
▸ Influence to adopt a tobacco free lifestyle.
▸ Can speak with authority in the community.
▸ Can be effective advocates for tobacco control in
community.
ROLE OF DENTIST

40. TEXT TOBACCO INTERVENTION
GUIDELINES FOR TOBACCO CESSATION : 5 A’s
▸ ASK
Check for oral sign to know if patient is using tobacco.
▸ ADVISE
Advise to stay away, affirm non-use, congratulate those who
quit.
▸ ASSESS
patients readiness to quit. Assess level of dependence.
▸ ASSIST
Set a firm quit date, support from family and friends, reduce
tobacco, anticipate challenges.
▸ ARRANGE
for follow ups. Revisits, telephone contact etc.

41. TEXT
PHARMACOTHERAPY
▸ NICOTINE REPLACEMENT THERAPIES (NRTs)
Nicotine Gum
Nicotine Patch
Nicotine Inhaler
Nicotine Nasal Spray
Nicotine Lozenges
▸ ANTIDEPRESSANTS
Buproprion SR
Selegeline
Clonidine
Nortryptiline

42. TEXT
COUNSELLING THOSE UNWILLING TO QUIT : 5 R’s
▸ Relevance of quitting
▸ Risks of continuing tobacco
▸ Rewards of quitting
▸ Roadblocks to quitting
▸ Repeat these at each visit

43. TEXT
▸ SCREENING
▸ EARLY DETECTION AND REFERRAL
▸ Community level early detection programs by primary
health care givers should be taken to detect precancerous
lesions and to educate them against tobacco use.
SECONDARY PREVENTION

44. TEXT
▸ SURGERY
▸ RADIOTHERAPY
▸ CHEMOTHERAPY
TERTIARY PREVENTION

45. TEXT CONCLUSION
▸ Dentist and other health personnel have a responsibility to
assist patients in minimizing risk factors, through effective
health education.
▸ Oral cancer can be reasonably detected and diagnosed in
early stages through a 5 min thorough examination.
• National - international health authorities, research
institutions, non-governmental organizations and civil
society to strengthen their efforts for the effective control
and prevention of oral cancer.

46. TEXT
Thank you
Dr. Aashna Dhingra
PG Dept. of Public Health Dentistry