Epidemiology of oral cancer

11
EPIDEMIOLOGY OF
ORAL CANCER
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22
CONTENTS
 INTRODUCTION
 DEFINITIONS
 MECHANISM OF CANCER -
CARCINOGENESIS
 THEORY OF FIELD CANCERIZATION
 MECHANISM OF CANCER METASTASIS

33
CONTENTS
 ORAL CANCER
– EPIDEMIOLOGY STAGES OF ORAL
CANCER
– TYPES OF ORAL CANCER
– CLINICAL PRESENTATIONS
– DIAGNOSIS OF ORAL CANCER
– TREATMENT AND PREVENTION OF ORAL
CANCER

44
CONTENTS
 SUMMARY AND CONCLUSION
 RECOMMENDATIONS
 REFERENCES

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66
INTRODUCTION
 Chronic diseases such as cancer, and other non-
communicable diseases are fast replacing
communicable diseases in India and other developing
countries.
 The burden of cancer is increasing worldwide despite
advances for diagnosis and treatment.
 Epidemiological studies have shown that many cancers
may be avoidable.

77
INTRODUCTION
 Tobacco is the most important identified cause of
cancer followed by dietary practices, inadequate
physical activity, alcohol consumption, infections due
to viruses and sexual behaviour.
 The mouth is a mirror for general health and well-
being and Poor oral health can interfere with vital
functions such as breathing, eating, swallowing and
speaking and significantly diminishes the quality of
life.

88
INTRODUCTION
 Oral cancers often occur out of long standing
potentially malignant lesions and conditions so called
premalignant lesions and conditions.
 Oral precancer is a intermediate state with increased
cancer rate which can be recognized and treated
obviously with much better prognosis than a full
blown malignancy.

99
Neoplasm
 Neoplasia (new growth in Greek) is the abnormal
proliferation of cells, resulting in a structure known
as a neoplasm.
 The growth of this clone of cells exceeds, and is
uncoordinated with, that of the normal tissues around
it. It usually causes a lump or tumor.
 Neoplasms may be benign, pre-malignant or
malignant.

1111
 A neoplasm can be benign, potentially malignant (pre-
cancer), or malignant (cancer).
– Benign neoplasms term that refers to a non-
cancerous mass or growth which is not life
threatening, because it does not spread and damage
adjacent tissues, structures, and organs)
– It includes uterine fibroids and melanocytic nevi
(skin moles).
– They do not transform into cancer.

1212
– Potentially Malignant Neoplasms include
carcinoma in situ. They do not invade and destroy
but, given enough time, will transform into a
cancer.
– Malignant Neoplasms are commonly called
cancer. This refers to a cancerous mass or growth
which can invade and destroy the surrounding
tissue, which may form metastasis and eventually
kill the host.

1313
DEFINITIONS
 A premalignant lesion is defined as
morphologically altered tissue in which cancer is
most likely to develop than in its apparently normal
counter part. (According to W H O)
 Leukoplakia, erythroplakia and palatal changes
associates with reverse smoking are examples of
premalignant lesions.

1414
 A premalignant condition is a generalized state
associated with a significant increased risk of cancer.
 A premalignant condition can be defined as “a
generalized disturbance or a disease state which
predisposes to the development of a neoplasm at a
particular site”.
 Syphilis, Oral Submucosis fibrosis, and Lichen planus
fall into this category.

1616
 Tumor or Tumour: originally, it meant any abnormal
swelling, lump or mass. However, the word tumor has
become synonymous with neoplasm.
 Neoplasm: the scientific term to describe an abnormal
proliferation of genetically altered cells. Neoplasms
can be benign or malignant:
– Malignant neoplasm or Malignant tumor:
synonymous with cancer.
– Benign neoplasm or Benign tumor: a tumor (solid
neoplasm) that stops growing by itself, does not
invade other tissues and does not form metastases.

1717
 Cancer is defined as a malignant tumor which
spreads very rapidly.
 Cancer is a class of diseases in which a group of cells
display uncontrolled growth (division beyond the
normal limits), invasion (intrusion on and destruction
of adjacent tissues), and sometimes metastasis
(spread to other locations in the body via lymph or
blood). (wikepedia)

1818
 Carcinoma is a malignant tumor occurring in
the epithelial tissue and spreading rapidly by
direct extension, through the blood circulation
or the lymphatic channels and giving rise to
secondary metastasis.
 It may affect any organ or part of the body.

1919
MECHANISM OF CANCER OR
CARCINOGENESIS
 Carcinogenesis is the process by which normal cells
are transformed into cancer cells.
 Carcinogenesis is caused by the mutation of the
genetic material of normal cells, which upsets the
normal balance between proliferation and cell death.
This results in uncontrolled cell division and the
evolution of those cells by natural selection in the
body.

2121
 The uncontrolled and often rapid proliferation of cells
can lead to benign tumors; some types of these may
turn into malignant tumors (cancer).
 Benign tumors do not spread to other parts of the body
or invade other tissues, and they are rarely a threat to
life unless they compress vital structures or are
physiologically active; for instance, producing a
hormone.
 Malignant tumors can invade other organs, spread to
distant locations (metastasis) and become life-
threatening.

2222
Mechanisms of carcinogenesis
Carcinogenesis is usually divided into three stages:
 Initiation
 Promotion
 Progression
Diet and other environmental variables can influence
each of these stages to alter carcinogenesis.

2323
Exposure to and Metabolism of Carcinogenic Agents

2727
Cancer Cells
Clonality
Autonomy
Metastasis
Oncogenes
Suppressor
genes

2828
Theory of Field Cancerization
 Slaughter et al 1953
 “Field of genetically altered cells”
 Suppression of tumor suppressor genes – TP53,
CDKN2A, pRb
 These cells proliferate and expand to adjacent tissues
causing further genomic damage.
 A recurrent tumor occurs even with completed
removal of the primary lesion.

2929
Different Field Cancerization Theories

3030
Mechanism of Cancer Metastasis
 Cancer cells have ability to invade the surrounding
tissues. The appearance of irregular invasion in
cancer affected tissues is the underlying reason for it
being called “Cancer” which is derived from the
Latin word “crab”.
 Metastasis is the process by which a tumor cell
leaves the primary tumor, travels to a distant site via
the circulatory system, and establishes a secondary
tumor.

3131
Forms of Cancer Metastasis

3232
Preferential Metastatic sites
Primary tumour Common Distant site (s)
Breast’ adenocarcinoma Bone, brain, adrenal
Prostate adenocarcinoma Bone
Lung small cell carcinoma Bone, brain, liver
Skin cutaneous melanoma Brain, liver, Bowel
Thyroid adenocarcinoma Bone
Kidney clear cell
carcinoma
Bone, liver, thyroid
Testis carcinoma Liver
Bladder carcinoma Brain
Neuroblastoma Liver, adrenal

3333
Reason for Organ Selectivity
Mechanistic theory: determined by the pattern of blood
flow.
“Seed and soil” theory: the provision of a fertile
environment in which compatible tumor cells could
grow

3434
Determining factors
 Appropriate growth factors or extracellular matrix
environment
 Compatible adhesion sites on the endothelial
lumenal surface
 Selective chemotaxis at which the organ producing
some soluble attraction factors to the tumor cells

3535
II) Molecular mechanisms of
Metastasis

3636
5 major steps in metastasis
1. Invasion and infiltration of surrounding normal host
tissue with penetration of small lymphatic or
vascular channels;
2. Release of neoplastic cells, either or single cells or
small clumps, into the circulation;
3. Survival in the circulation;
4. Arrest in the capillary beds of distant organs;
5. Penetration of the lymphatic or blood vessel walls
followed by growth of the disseminated tumor cells

3838
Stages of metastasis
 Invasion : primary tumour cells enter circulation.
 Circulation to the secondary site of tumour growth.
 Colonization : formation of secondary tumour.

3939
Tumor Invasion
1. Translocation of cells across extracellular matrix
barriers
2. Lysis of matrix protein by specific proteinases
3. Cell migration

4040
Components of Invasion
a) Matrix degrading enzymes
b) Cell adhesion
c) Cell motility

4141
ORAL CANCER
 Oral cancer is part of a cancer group called Head
and Neck Cancers, and is defined as an
uncontrollable growth of cancerous cells that invades
the mouth (called oral cavity) and the part of the
throat behind the mouth (called oropharynx).
 Cancers of the head and neck are most often found in
people who are over the age of 45.
 Like most cancers, cancer of the lip and oral cavity is
best treated when found early.

4242
Types of Oral Cancer
 Types
 Oral cancer is classified according to two criteria:
1. The cancer location.
 According to this criterion, there are two types of oral
cancer:
(1) Oral cavity cancer - the cancer that starts in the
mouth, which includes the tongue, lining of the
cheeks, gums and teeth, upper or lower jaw, the hard
palate (the mouth’s roof), the mouth’s floor (the area
beneath the tongue), and salivary glands.

4343
(2) Oropharyngeal cancer - the cancer that starts in the
oropharynx, which includes the soft palates (the back
of the mouth), the base of the tongue, uvula, and
tonsils (one of two small masses of lymphoid tissue
located on either side of the throat).
 Around two-thirds of the oral cancers are found in the
mouth, while one-third are found in the pharynx

4444
2. The cells where the cancer starts.
 There are two types of oral cancer:
1. Squamous cell carcinoma: This is a type of
cancer that starts in the flat cells (called squamous
cells) that cover the surface of the oral cavity and
orophadynx. Squamous cells carcinoma represents
more then 90 percent of all oral cancers. In its early
stages, this cancer is confined to the lining layer of
the cells and is called carcinoma in situ, but when it
extends beyond the lining, it is called invasive
squamous cell carcinoma.

4545
 A variant of squamous cell carcinoma is verrucous
carcinoma. This is a low-grade cancer that rarely
metastasis, and has a good prognosis.
 This type of oral cancer is common among patients
that chew tobacco or use snuff (a fine -ground
tobacco which is sniffed or snorted).
 It represents less than 5 percent of all diagnosed oral
cancers.
2. Minor salivary gland cancer: This is a type of
cancer which starts within the salivary glands located
in the oral cavity and oropharynx lining tissue. This is
a rare type of oral cancer.

4646
Epidemiology
 3, 00, 000 new cases worldwide annually.
3% of
total cancers
In developed countries – eighth most common
One lakh individuals suffering in a year.
7% of all cancer deaths in males
and 4% in females

4747
Oral Cancer: Epidemiology
 Annually: 30,000 new cases diagnosed
: 8,000 deaths
 Average age at diagnosis: 60 years (2/3
among elderly)
 Major risk factors: tobacco and alcohol
use
 Male to female ratio: 2:1
 Over 50% have diagnosed with
metastasis.
High
incidence
in several
Countries
Different
intraoral
location
in different
Populations

484848
Prevalence and Incidence –International
Perspective
 Oral cancer is one of the ten leading cancers.
 In highly industrialized countries it accounts for only
3-5 % of all the caners where as in some developing
countries it is up to 40%.
 About 2.5 lakhs new cases occur every year in
countries like India, Pakistan Bangladesh
Afghanistan, Srilanka and some countries in south
east region.

4949
 The highest rates are registered in a few developing
countries particularly those of south east Asia.
 There also pockets of high incidence rates in western
populations such as that of Bas Rhin in France.
 The peak age frequency of occurrence is at least a
decade earlier than that described in Western
literature.

5151
Age adjusted incidence of oral
cancer/lakh
 Europe 2.0 (UK) - 9.4 (France)
 America 4.4 (Cali,Colum) - 13.4
(Canada)
 Asia 1.6 (Japan) - 13.5 (India)
 Australia 2.6 (Maori) - 7.5 (S.Aust)

5252
Prevalence rates
 Burma - 0.03%
 India - 0.1%
 The relative frequency of oral cancer in
several countries compiled over a 25
year period varies from 2-48%

5353
Trends in Incidence
 Slight ↓ Puerto Rico, Finland, Cali,Columbia
 Steady UK, Japan
 ↑ Yugoslavia
 Signi.↓ 1964-1982 in Bombay
Difficult to compare, but a decreasing trend is indicated

555555
Indian scenario
 Oral cancer is the leading type of cancer in India.
 India has one of the highest incidence of Oral
cancer in the world
 However in western countries also the cancer of
the mouth and pharynx is gaining importance as
the prevalence is increasing. [Johnson 1991, Moller 1989]

565656
 Sex ratio reveals a 2:1. Preponderance of male
patients.
 Only 10% to 15% of cases present in localized stages.
 Oral cancer ranks number one among men and
number three among women in India. Oral cancer
constitutes 12% of all cancers in men and 8% of all
cancers among women. [Sankaranarayanan R.:Oral caner in
India: An epidemiologic and clinical review. Oral Sirg. Oral Med. Oral
Path.69:325-330,1990. ]

5757
 Oral cancer is a major health problem in India.
 In India it is estimated that among the 400 million
individuals aged 15 years and over 47% use tobacco
in one form or the other.
 In India, the age standardized incidence rate of oral
cancer is 12.6 per 100 000 population. [WHO]

585858
 Prevalence rate of 15 per 1000 in the country.
 Gender differences were less marked in lower age
group, adults males were more affected
 In all age groups, there appeared to be a higher
prevalence amongst rural rather than urban residents.

5959
Epidemiologic triad of Oral Cancer

6060
 The exact causes of oral cancer are not known, but
there are a few factors which increase the risk for
oral cancer.
 There is a considerable overlapping of epidemiologic
factors for oral cancer.

6161
Some of the host risk factors are:
 Age: Men over the age of 40 are at higher risk for
developing oral cancer.

6262
Age
Distribution

Prolonged exposure
Decreased immunity
Cellular ageing
Changing
exposure to
etiologic
agentsPatel MM,
Pandya AN
2004
Younger
population
Older population

636363
Indian statistics for 2002- 2003
Age Oral cancer
prevalence (%)
Leukoplakia
prevalence (%)
5 years 0.1 0.2
12 years 0.1 0.2
15 years 0.5 0.2
35-44 years 0.6 2.1
65-74 years 0.7 3.2

6464
 A comparison of the age specific incidence rates of oral
cancer during 1990-2000 in Allahabad showed that the
incidence was maximum in the 50-59 years age group
and squamous cell carcinoma grade I was the most
prevalent type.
 Of the total of 759 biopsies from oral cavity, 303
malignant cases. 232 (76.57%) were males and 71
(23.43% were females with a male to female ratio of
3.27:1.
Age specific incidence rate and pathological spectrum of oral cancer in Allahabad;
Ravi Mehrotra, Mamta Singh, D Kumar, AN Pandey, RK Gupta, US Sinha

6565
 Gender: Men are at higher risk than women to
develop oral cancer.
Males Registry Females
16.7 Bombay 9.0
14.9 Poona 9.4
13.0 Madras 12.6
10.2 Bangalore 17.2
INDIA...

6666
Location of Oral Cancer
 90-99% of all oral malignancies are squamous cell
carcinoma.
 The tongue was the most frequently involved site--
found in 42.57% cases. On an average, 63 new cases
of oral cavity per annum were detected during this
period. [Age specific incidence rate and pathological spectrum of oral cancer in
Allahabad; Ravi Mehrotra, Mamta Singh, D Kumar, AN Pandey, RK Gupta, US Sinha]

676767
Distribution of oral mucosal conditions by
location in mouth
Location Oral cancer Leukoplakia
Rural Hard and soft palate Buccal mucosa
Urban Commisures of lip Buccal mucosa
National Vermilion border ,
hard and soft palate
Buccal mucosa

6868
 Race: African Americans are at higher risk than
Caucasians to develop oral cancer.
 Carcinoma of the nasopharynx is 20-30 times more in
chinese than in other races.
 Custom and Habits: The Prevalence of oral cancer is
less in 7th day Adventist Christians than other
Christian population because of the strict prohibition
of smoking and alcohol by the church.
 Certain cultural pattern encourage smoking and
alcoholism like in tribal people (Navago Indians, Red
Indians)

6969
Genetic predisposition
 Genetic studies have shown that neoplasms tend to
occur in families.
 Individuals with GSTM1 null genotype may be at
higher risk of oral cancer development. The study
showed risk of oral cancer development in habitual
controls with lower antioxidant enzymes, lower
oxidative stress markers, and higher lifetime tobacco
exposure.[Tobacco, antioxidant enzymes, oxidative stress, and genetic susceptibility in oral cancer:
Am J Clin Oncol. 2008 Oct;31(5):454-9 Am J Clin Oncol. 2008 Oct;31(5):454-9 ]

7070
 Poor oral cavity hygiene and ill-fitting denture:
These two factors can increase the risk for developing
oral cancer when associated with tobacco use and
alcohol consumption, offering a perfect location for
tumors to develop.

717171
Precancerous Oral lesions
 Leukoplakia is the most common premalignant oral
lesion.
 Leukoplakia is described as a white patch which
cannot be rubbed off and cannot be diagnosed as
another specific disease entity.
 The rate of transformation to malignant lesions varies
from 1-3%

727272
 In a large 10 year follow-up study in India, the age
adjusted incidence rate of Leukoplakia per 1000
population per year varied from 1.1 to 2.4 in men and
from 0.2 to 1.3 in women.
 The highest rate of transformation was reported for
nodular homogenous erythematous base leukoplakia
a rate of 16 per percent per year.- Gupta et al 1989.

737373
 Silverman has reported that leukoplakia in non
smokers referred to sometimes as idiopathic
leukoplakia exhibit a higher rate of malignant
transformation than in smokers 16%.
 Erythroplakia a bright red velvety plaque that cannot
be characterized either clinically, or pathologically as
being due to other identified conditions is also
associated with higher frequency of carcinoma.

7474
Infectious Agents
 Syphilis- tertiary stages
 Viruses

7575
 Infection with viruses: There are several viruses that
seem to increase the risk for oral cancer:
– Herpes Simplex Virus Type I
– Human immunodeficiency virus

7676
 Saranath has reported that
Oral cancer :25-50% prevalence of EBV
Premalignant lesions 0-13%
Normal mucosa : 4 - 28%.
 HPV 16 was detected in higher proportion of oral
lesions compared to oral cancer cases probably
impling its importance in early events of
carcinogenesis D’costa et al, Saranath.1999

7878
 The oral complications of tertiary syphilis center upon
gumma formation, and much more rarely, syphilitic
leukoplakia (and risk of oral squamous cell carcinoma)
and neurosyphilis.
 An association between tertiary syphilis and oral
squamous cell carcinoma—particularly of the tongue—
has been suggested for many years.
 Both clinically- and serologically-based studies have
suggested an increased prevalence of syphilis in patient
groups with squamous cell carcinoma of the tongue (up
to 60% in one study), the association being stronger in
males than females. [Trieger N, Ship II, Taylor GW, Weisberger D.]

8080
Environmental factors
 Tobacco
 Alcohol
 Dietary factor
 Physical agents such as sunlight, trauma, heat,
etc.
 Exposure to radiation (therapeutic/
environmental/ occupational)

818181
7’s of oral cancer
 Smoking
 Spirit
 Spices
 Sepsis
 Sunlight
 Sharp tooth
 Syphilis
Causes and Risk Factors

8282
 Smoking cigarettes, pipes, or cigars: This is one of
the main risk factors that causes oral cancer. Smoking
cessation represents one of the most effective
prevention approaches.
 Use of smokeless tobacco: The risk for oral cancer is
also increased when people use smokeless tobacco
such as plug, leaf, and snuff.

8383
200 million -16.6% of world’s smokers
(35% males, 3% females
70% 20%
Tobacco: 90% of oral cancers in India and SE Asia
Chewing
Smoking
tobacco

8484
Nicotiana tobacum / rustica
Chewing
Smoking
Snuff

8585
Tobacco smoking
Nicotine content of 1.7 to 3mg.
Tar content – 45-50mg
Small amounts of coarsely ground
tobacco
34% of total production
Bidi smoking - Most popular
0.2-0.3 gm Sun dried tobacco
flakes in temburni / tendu
leaf

8686
Cigarette smoking
 1 gram of tobacco cured in the sun
or artificial heat is covered with
paper.
 sugars, flavoring and aromatic
ingredients
 1-1.4mg of nicotine and 19-27mg
tar
 31% of tobacco grown in India is
used for manufacture of cigarettes
51% are filter tipped - 12 mm
Common in Urban areas

8787
Cigars - air cured and fermented
tobaccos with a tobacco wrappers
 Chutta/cheroor, Cheroot, Dhumti
Dhumti – reverse smoking by women in AP

8888
Pipes…Earliest forms
Chillum
10-14cm
Hookah/Hubble-bubble
Hookli - Gujarat
7-10 cm

9090
“Reverse Smoking”
 Common in India - Vishakapattanam and Srikakulam.
 The temperature of the palatal mucosa may go up to
580
c.
 The reasons for keeping the lighted end inside the
mouth may be due to: Not to expose lighted end to
wind and water, prevent husband from seeing it,
prevent ashes from falling on child, toothache and
halitosis relief.

9191
 Pindborg et al conducted an epidemiological survey
of 10,169 villagers in the Srikakulam district of south
India and found that 43.8 % of those interviewed
practiced reverse smoking.
 Leukoplakia wan found in 8.8 percent of reverse
smokers compared to 0.1 percent in nonsmokers.
 Ten patients found to have oral cancer were all reverse
smokers.
 Reddy et al. found that reverse smoking was practiced
by 73 of 100 patients with oral cancer. Reddy, et al
reported characteristic histological findings of the oral
cavity in biopsies obtained from reverse smokers.

9292
Evidence of risk from smoking tobacco
 Cigarette smoking- Major cause
 Pipes/cigars - Similar risk
 Mortality ratios - ↑ with number
- ↓ with cessation
 Alcohol use acts synergistically
International Agency for Research on Cancer (IARC)
identified tobacco smoking as an important cause of oral cancer
Report of
Surgeon General
US 1964
• Consistency
• Strength
• Specificity
• Temporality
• Coherence

9393
South-East Asia
 Cigar
 Cigarette ↑ risk by 6 times
 Hookah
 Pipe ↑ risk by 16 times
 Bidi ↑ risk by 36 times
Relative risk for smoking in India and Sri Lanka - 2.1 for males
and 11.5 for females

9494
Loose-leaf tobacco - Made from fermented cigar leaf
tobacco to which is added sugars and flavoring agents.
It is sold in loose pieces or strips.
Twist
tobacco
Pan

9595
Manipuri tobacco:
 Mixture of tobacco, slaked lime, finely cut areca nut,
camphor and cloves.
 About 7% of villagers use it and is strongly
associated with leukoplakia.
Mawa:
– Thin shaving of areca nut with tobacco and slaked
lime. It is sold in cellophane papers.
– Before consumption, the packet is rubbed to mix the
contents and is chewed until it becomes softer after
which it is transferred to mandibular groove

9696
 Khaini: Powdered sundried, tobacco,
slaked lime mixture. Premolar region of
mandibular groove.
 Mishri/Masheri: Roasting tobacco on hot metal plate.
With/without catechu. Used to clean teeth.
 Zarda: Tobacco leaf boiled in water with lime and
spices. It is chewed.
 Gudakhu: tobacco and molasses to clean teeth.
 Nass: Tobacco, ash and oil.
 Naswar: Tobacco, slaked lime, oil.

9898
Smokeless Tobacco: Snuff
 It is finely powdered tobacco. It is of 2 types
- moist and dry.
 A moist type used in the mouth and a small amount is
held between the cheek and the gum.
 Dry type which is finely pulverized tobacco and is
used orally or nasally.
 Bajjar is a dry snuff used by 14% of Gujarat women.
It is carried in metal container, a twig is dipped into it
and applied over the tooth and gingiva. It is associated
with the carcinoma of the gingiva.

9999
Evidence
 Bantu people in South Africa - Nasal
snuff - Maxillary antral carcinoma
 Sudan - Toombak - NaHCO3 - lower
labial sulcus - increased cancer
Verrucous and OSCC most common

100100
Betel quid - tobacco, Areca-nut, Lime,
Catechu, Spices...
 IARC- Animal and Human studies.
 Migrant communities studies in UK.
 Gutkha - Increasing incidence.
 Woman Smokeless Tobacco users in Mumbai –
Relative Risk -1.35 as compared to 1.39 among
cigarette smokers.
 Case-control studies (2000-2003) suggest strong
statistical association and dose-response relationships
for Smokeless Tobacco use and cancers of the oral
cavity.

101101
 Nass - Uzbekistan
 Shamma- Yemen - 30 fold increase in oral cancer
incidence
 Europe - uncommon, except in scandinavian - moist
Swedish snuff - Snus - lip cancer

102102
Betel-tobacco and oral cancer
 Earliest forms of evidence
 High frequency in areas where habit
widespread.
 Parsees - less prevalence
 Malaysia: Indians > Malays
 High frequency of habit among cases
 Site of origin - Placement of tobacco quid

103103
 Prevalence among people with and
without tobacco habits
 14/38 - in solely betel-tobacco
chewers
 24 - Tobacco users
 None among non-users
Smokeless tobacco - gateway to smoking,
if both used - more toxic

104104
More than 2500 chemical constituents
The most important among them are:
 Polyacrylic aromatic hydrocarbons - carcinogen.
 Nicotine - carcinogen
 Phenols - Produce ganglionic stimulations and
depressions and
- cause tumour promotion.
 Benzopyrene - tumour promotion.
 Carbon monoxide - impairs oxygen transport and
repairs
 Formaldehyde and oxides of nitrogen - ciliary toxicity
and irritation.
 Nitrosamine - most potent carcinogen. (TSNA)

105105
Tobacco use in India…
 Eight largest exporter of tobacco
 The tobacco industry provides support to about 60
lakh farmers and 75 lakh workers.
 About 80% of tobacco used is produced
domestically.
 Per capita consumption is 0.83 Kg per year.
 The government has 39% stake in cigarette
industry.

106106
Tobacco use in India…
 10 - 15 years age : Males - 20% - 25%
females - 3%
 25 years: Males – 60%, females – 15-20%
 Recreational compulsion in teens.
 Other reasons include: to relieve hunger,
overcome boredom and anxiety,
strengthens gums, induces euphoria, for
concentration etc.
8 lakh persons
die from
tobacco related
diseases
every year in
India alone,
every
cigarette
reducing
the life by 5.5
minutes
consumption continues to grow in India at 2–3% per annum, and by 2020
it is predicted that it will account for 13% of all deaths in India
65% men and 33% women use some form of tobacco.

107107
Health consequences of
Tobacco consumption in India
 Tobacco–related cancers account for approximately
half of all cancers among men and one–fourth among
women.

108108
The high incidence of oral cancers in India
due to
 Processing of tobacco in India is done by farmers
and small companies with little control over
fermentation and curing.
 In India, tobacco is used along with Betel leaf
[Piper betel], sliced areca nut [Areca catechu] and
powdered slaked line which enhance the effect.
 Indian users often smokeconsume alcohol
concurrently, thus increasing the effect.

109109
 This is another risk factor that directly causes oral
cancer.
 Studies conducted in developed countries suggest
that tobacco and alcohol, together, increases the
risk for oral cancer by almost 80 percent because
they act synergistically.
Excessive consumption of alcohol

110110
 Dehydrating effects on the mucosa
 Acetaldehyde accumulation - Free
radicals
 Alcohol may also act as solvent and
enhance penetration of carcinogens into
target tissue.
Synergistic
Effect -
75% of
all oral
Cancers.
Multiple
primary
Cancer sites
↑ oral cancer
deaths

111111
 Exposure to Sunlight (Ultraviolet Radiation)
without proper sunscreen protection: The risk for
lip cancer is high when exposed to the sun without a
proper protection.
 Medical treatments: Patients that undergo a renal
transplant are at a higher risk to develop Lip Cancer.
This risk might be linked to the immunosuppressant
effect that can follow the transplant.

112112
Blood Groups
 Association of blood groups to oral cancer has been
observed.
 Blood Group A - higher susceptibility.
 It has been reported that group O showed the least
susceptibility, groups B and AB, showed doubtful
susceptibility and blood group A had higher
susceptibility to oral cancer.

113113
Dietary Factors
 The importance of diet and nutrition in the etiology of
human cancer has gained wide acceptance.
 The observation that migrant populations experience
the cancer rate of the host country, bolstered the
evidence that international differences in the rates
were the result of the environmental and lifestyle
factors including among other possibilities dietary
and nutritional factors.

114114
 Several major case control studies have been reported
from the western countries. One of the largest case
control study was reported from the US on 871 cases
and 979 control, frequency matched for age and sex.-
McLaughlin et al 1988.
 A deficient diet: The lack of vitamin A, C, and E,
iron, selenium, and folate in the diet can increase the
risk for oral cancer.
 Meat, fish, grains and dairy products showed no
association with the risk in females, where as in
males, meat and dairy products increased and fish
decreased the risk.

115115115
 A single case control study exploring the association of
individual food items has been reported from India
region of high incidence or oral pharyngeal cancer –
Notani and Jayant.
 This study was based on cancers in males at a large
referral hospital, and compared the diet of cancer cases
with two groups of controls, hospital and community.
 The findings were reported for the usual diet before the
onset of the disease in terms of frequency of intake,
after adjusting for tobacco use. A protective effect was
observed with an intake of vegetables, fish, pulses and
buttermilk. The use of red chili powder emerged as a
risk factor.

116116
Poor
oral hygiene
Syphilis Chronic Candida HSV-I
Blood group
A>B,AB>O
Leather,
cotton,
Textile mills

117117
Oral Carcinogenesis
DNA
Damage
Mutagens Spontaneously
Chemicals:
TSNA
Acetaldehyde
PAH
Physical:
Ionizing radiation
Natural radiation Infective agents:
Candida
HPV

118118
STAGES OF ORAL CANCER
 Stage of cancer in the lip or oral cavity is important in
order to plan the best course of treatment.
 The most common staging system used for oral
cancer is the American Joint Committee on Cancer
(AJCC) TNM system.

119119
The TNM system refers to:
 Tumor features (T) - size and invasion level;
 Lymph Nodes involved (N) - lymph nodes are part of
the body immune system;
 Cancer Metastasis (M) - Metastasis stage is the last
developmental cancer stage when the cancer has
spread to distal organs (organs situated far from the
origin point).

120120
T stage for oral cancer
 T0: No primary tumor is present.
 T1: The tumor is 2 cm or less.
 T2: The tumor is 4 cm or less.
 T3: The tumor is larger than 4 cm.
 T4: The tumor is larger than 4 cm, and it has deeply
invaded the tumor invades adjacent structures
(mandible, tongue musculature, maxillary sinus, skin).
 Tis: Carcinoma in situ (the cancer is confined to the
tissue where it developed).

121121
N stage for oral cancer
 N0: No lymphatic nodes are affected.
 N1: The cancer has affected one homolateral
lymphatic node, but its size is smaller than 3 cm.
 N2: The cancer is present in one or more homolateral
lymphatic nodes, but their size is smaller than 6 cm.
 N3: The cancer is present in few homolateral or
bilateral lymphatic nodes, having a size bigger than 6
cm.

122122
M stage for oral cancer
 M0: No metastasis are present.
 M1: The cancer has spread to distal organs
(organs located far from the origin point where
the cancer had developed initially).

123123
 Based on the TNM system, the oral cancer is
classified in four stages:
 Stage I: (T1, N0, M0)
In this stage, the cancer is confined to tissue where it
initially occurred, and the tumor is not larger than 2
cm.
 Stage II: (T2, N0, M0)
In this stage, the tumor is no larger than 4 cm.
 Stage III: This stage includes two substages:
 Stage IIIA: (T3, N0, M0)
In this stage, the tumor is larger than 4 cm, but no
lymphatic nodes or metastasis are present.

124124
 Stage IIIB: (T1, T2, T3, N1, M0)
In this stage, the tumor size is either less than 2 cm,
under 4 cm, and 4 cm or over, but the cancer has
affected one homolateral lymphatic node.
 Stage IV: This stage includes three substages:
 Stage IVA: (T4, N0, M0)
In this stage, the tumor is larger than 4 cm, and it has
deeply invaded the muscle, bone, or other adjacent
structures

125125
 Stage IVB: (Any T, N2 or N3, M0)
In this stage, the tumor can have several sizes (1) less
then 2 cm, (2) less or more than 4 cm, (3) more than 4
cm but it has deeply invaded the muscle, bone, or other
adjacent structures, or the cancer has spread to several
homolateral or bilateral lymphatic nodes.
Stage IVC: (Any T, any N, any M)
In this stage, there are several situations which include
the tumors having different sizes (between 2 and more
than 4 cm), the cancer is present in the homolateral or
bilateral lymphatic nodes and in other organs within the
body.

126126126
Clinical presentations
of
Cancer of Oral
Mucosa
 More than 90% of the oral
cancers are squamous cell
carcinoma
and remaining are salivary gland tumors, lymphoma,
sarcoma and others.

127127
Lymphadenopathy
 Enlargement of one or more
lymph nodes may be a response
to infection of an ulcerated tumor,
but may indicate metastasis if
multiple, hard, matted together,
fixed to skin or deeper structures.
 The precise group of nodes likely to be
affected depends on the location of the
primary cancer.

128128
CARCINOMA OF BUCCAL
MUCOSA
Chewing tobacco and
retaining tobacco quid
in buccal vestibule.
Chronic trauma /
irritation by sharp
teeth.

129129
CARCINOMA OF TONGUE
 It is relatively common,
with 3% of all
malignancies arising
within the oral cavity.

130130
CARCINOMA OF
TONGUE
Bidi sm
oking

131131
 Tongue cancer is more common than all forms of oral
cavity cancer except those of the lip and occurs with
increasing age.
 It is uncommon before the age of 40 and the highest
incidence of the disease is in the 6th and 7th decades
with sex incidence being a 3:1 male predominance.

132132
CARCINOMA OF PALATE
Usually seen in reverse smoking

133133
CARCINOMA OF GINGIVA
Chronic irritation and inflammation of gingiva
over a period of several years due to calculus
formation and collection of micro organisms

134134
CARCINOMA OF FLOOR OF
MOUTH
Smoking pipes or cigars
Alcohol consumption
Leukoplakia
Poor oral hygiene

135135
CARCINOMA OF LIP
Pipe smoking
Syphilis
Sunlight
Poor oral hygiene

136136
 Carcinoma of the lip is a relatively common malignancy of the
head and neck region, accounting for approximately one
quarter of oral cavity cancers. Males have this type of cancer
about twice as often as females.
 Tobacco products, especially smokeless tobacco, is a primary
cause.
 This type of cancer is more common among individuals in
their 50s, 60s and older.

137137
Medical Tests & Diagnosis
The diagnosis procedure procedures for oral cancer
include the following :
 Anamnesis (detailed medical review of past health
state)
 Physical examination
 Biopsy
 Exfoliative cytology
 Toludine blue staining
 Imaging techniques - Computed tomography scan,
Ultrasound, Magnetic resonance imaging, Endoscopy

138138
Anamnesis (Detailed Medical Review of
Past Health State):
 One of the first steps in establishing an oral cancer
diagnosis is a detailed and complex medical review of
a patient's past health problems and general health
state, family medical history, oral cancer risk factors
(especially smoking habits, tobacco and alcohol use),
and symptoms.

139139
PHYSICAL EXAMINATION
 During a physical examination, examination
is carried out of the oral cavity and pharynx,
the face, neck, and lips looking for signs of
oral cancer.
 The patient is examined for any possible
lump, abnormal or discolored tissue, or
sores.

140140
Brush Biopsy of Oral Cancer
 It is a procedure in which tissue
samples are removed (with a needle
or during surgery) from the body for
examination under a microscope to
determine if cancer or other
abnormal cells are present.

141141
Exfoliative Cytology
 Histologic examination of
surface cells scraped from
a suspected lesion with a
tongue blade.
 Accuracy is highly variable, weak in detecting
premalignant lesion.
 False positive and False negative are common.

142142
Toluidine Blue stain
 It is used as an extra tool for
the identification of patients
suspected with oral cancer
lesions.
 Toluidine Blue is a cationic metachromic dye which
selectively binds to the free anionic groups such as
sulphate, phosphate and carboxylate radicals of large
molecules. It is used as an in vitro nuclear stain, binding
the phosphate groups of nucleic acids.

144144
Computed Tomography
 This imaging test is similar with an x-ray test, and
creates a detailed, cross-sectional image of the body.
 This test can identify abnormal mass tissues.
 A CT scan is usually performed in two steps for a better
diagnosis outcome:
First, the targeted area is scanned without a contrast
agent.
Second, the targeted area is scanned after a contrast
agent was administrated.
In patient that suffer from oral cancer, this technique is
used to localize metastases.

145145
Magnetic resonance imaging (MRI)
 An MRI is an advanced technique that uses radio
waves and strong magnets to reveal a complete image
of a targeted area of the body.
 The energy from the radio waves is absorbed by the
tissues and then released into a pattern that allows the
cancer to be detected and diagnosed.
 This technique is also used to establish whether or not
the cancer has spread, and to visualize its location
within the body.

146146
Ultrasonography
 Ultrasound imaging is a medical technique that uses
high-frequency sound waves to create an interior image
of the body on a special computer screen.
 This image is formed from the echoes of the sound
waves on the surface of the organs.
 Abnormal tissue masses and organs reflect sound waves
differently. This test involves a device called transducer,
that is placed on the upper part of the abdomen, and a
computer that translates this sound into an image.
 Ultrasound imaging is a safe, noninvasive and fast test
that can detect tumors.

147147
Endoscopy
 This is a minimally invasive, painless diagnostic
procedure used to visualize interior surfaces of
certain organs and cavities.
 During this procedure, a flexible tube, called an
endoscope, is inserted into the body in order to
provide a clear image of the targeted area.
 This procedure is used to investigate tissues within
the pharynx area which cannot be visualize during a
normal examination.

148148
Treating cancer
Surgery
Chemotherapy
Radiation
Cancer
Prevention of
Cancer
Causes of cancer
Genetic changes
Smoking, diet, sunlight…
TREATMENT AND PREVENTION OF
ORAL CANCER

149149
TREATMENT OF ORAL CANCER
 Early cancers (Stages I and II) of the lip and oral
cavity are highly curable by surgery or radiation
therapy, with the choice depending on the anticipated
functional and cosmetic results.
 Advanced cancers (Stages III and IV) are usually
treated with a combination of surgery and
radiotherapy. A few patients with small lesions who
have no involved lymph nodes larger than 3/4 inch
might receive either surgery or radiation

150150
 Patients with these stages commonly develop
recurrences near the primary tumor or metastatic
disease after treatment and should be considered for
clinical trials involving radiation modifiers or the use
of combination chemotherapy in addition to surgery
and/or radiation.
 Patients whose tumors grow into blood vessels have a
worse prognosis.

151151
 For Recurrent Cancer, treatment depends on the
location and size of the recurrent tumor, as well as
the nature of the original treatment.
 If radiotherapy was used initially, surgery is
preferred. If surgery was used initially, Radiotherapy
or a combination of both will be used.
 Because results are poor after using the "other"
treatment for a recurrence, clinical trials using
chemotherapy or hyperthermia should be considered.

152152
General Treatment
 Surgery
 Radiation
 Chemotherapy
– Etoposide (epipodophyllotoxin, inhibits
topoisomerase enzyme in DNA)
– Ifosfamide (alkylating agent, acts as a prodrug)
http://www.mdanderson.org/
Inability to
Cell
Division
– Taxol (inhibit Tubulin protein
depolymerization)
– Vincristine (inhibit polymerization
of microtubules)

153153
 Hormonal Therapy
 Biological Therapy
– Interferon alpha was one of the first
immunotherapies used to treat cancer.
 Stem cell & bone marrow transplants

154154
Gene therapy: Cancer-specific killing delivering a
Therapeutic Gene
Gene therapy vector design strategies
for the treatment of cancer.
Dong JY, Future Oncol. 2005
Chemogene therapy: osteocalcin
promoter-based suicide gene therapy in
combination with Methotrexate in a
murine osteosarcoma model.
Cheon J, Cancer Gene Ther. 1997
Or combined with other therapies…
Non-viral cancer gene therapy: Beyond
delivery; S Akhtar et al, 2005

155155155
Survival rates
 Oral cancer has one of the lowest 5 year survival rates
for any major cancer sites, but when detected early
the prognosis is remarkably better than any other
cancer.
 The 5 year survival rate is about 50-80% in patients
with early cancer and for advanced stages it is about
10-20%.

156156
PREVENTION OF CANCER
Cancer is preventable..
65-80% of oral cancer is
Environmental,
attributable to Lifestyle and thus

157157
Treating cancer
Surgery
Chemotherapy
Radiation
Cancer
Prevention of cancer
Causes of cancer
Genetic changes
Smoking, diet, sunlight…

158158
 Nutrition
 Physical Activity
 Occupancy
 Quitting Tobacco and Alcohol
 Lung cancer, Oral cancers
 Limiting sun exposure, UV
radiation
HOW TO PREVENT
CANCER?

159159
HOW TO PREVENT CANCER?
 Prostate cancer  early detection
 Testicular cancer  early detection
 Breast cancer  early detection
 Cervical cancer  early detection
 Colon cancer  by following screening guidelines,
increasing activity levels, and eating a low-fat,
healthy diet.
– Colon is the third most common cancer in both
men and women.

160160
HOW TO PREVENT ORAL CANCER?
Many risk factors can be modified but not all can be
avoided.
 Tobacco and Alcohol Use: Tobacco use (cigarettes,
pipes, cigars, and smokeless tobacco) is responsible
for most cases of oral cancer.
 Alcohol, particularly beer and hard liquor, are
associated with an increased risk of developing oral
cancer.

161161
 The risk of developing oral cancer is higher in people
who use both tobacco and alcohol. Avoiding or
stopping the use of tobacco decreases the risk of oral
cancer. It is not known if stopping the use of alcohol
decreases the risk of oral cancer.
 Sun Exposure: Exposure to sunlight may increase
the risk of lip cancer, which occurs most often on the
lower lip. Avoiding the sun and/or using a sunscreen
or colored lipstick on the lips may decrease the risk of
lip cancer.

162162
 Other Factors: Some studies suggest that being
infected with the human papillomavirus (HPV) may
increase the risk of oral cancer.
Chemoprevention:
 Chemoprevention is the use of drugs, vitamins, or
other agents to prevent or delay the growth of cancer
or to keep it from coming back.

163163
 Tobacco users who have had oral cancer often
develop second cancers in the oral cavity or nearby
areas, including the nose, throat, vocal cords,
esophagus, and windpipe.
 Studies of chemoprevention in oral cancer are under
way, including chemoprevention of leukoplakia and
erythroplakia.

165165
Primordial prevention
 Healthy lifestyles Healthy eating habits, exercise,
no smoking & drinking .
 Almost all the age groups should be targeted.

167167
Primary Prevention
 Cancer prevention- Addressing the etiologic agents
 Ban tobacco
 Behavioral modifications
 Oral Cancer Tobacco use, alcohol consumption,
poor diet.
 Primary prevention by habit intervention is the most
cost effective approach to the management of oral
cancer.

168168
Health education approach should be
aimed to …..
 Encourage individuals not to adopt any tobacco
habits.
 Encourage individuals who use tobacco to stop.
 Encourage individuals who use tobacco and cannot
stop to at least decrease their use.
 Encouraging individuals to rinse their mouth after
chewing tobacco.
 Encourage people not to retain quid in the mouth
during sleep.
 Encourage public support for legislation.

169169
Regulatory services
LEGISLATION
 Prohibit sale of tobacco
to minors.
 Place health warning
signs wherever tobacco
products are sold.

170170
LEGISLATION
PROHIBIT ADVERTISING OF TOBACCO
PRODUCTS ( 1975-2001)

171171
February 2001 Cigarettes and other Tobacco
Products (Prohibition of Advertisement and
Regulation of Trade and Commerce, Production,
Supply and Distribution) Bill
It includes the following key demand reduction
measures:
 Outlawing smoking in public places.
 Forbidding sale of tobacco to minors.
 Requiring more prominent health warning labels and
 Banning advertising at sports and cultural events.

172172
LEGISLATION…
 Restrict Smoking Of Tobacco
Products In Enclosed Public
Places
 Increase Taxes On Tobacco
Products
 Regulate Content Of Tobacco
Products
 Celebrating days like ‘no
tobacco day’ on 31 of may

173173
Service approach
 The active search for disease among apparently
healthy people is a fundamental aspect for prevention.
 Treatment in early stage is usually acceptable to
asymptomatic patients and provides benefits over later
treatment.
 Facilities for diagnosis and treatment exists.
 natural history of disease known.

174174
 The screening tool is inexpensive.
 Safe screening for oral cancer is feasible because:
– oral cavity is easily accessible and its examination
poses relatively little discomfort to the patient.
– It provides an opportunity to identify and counsel
patients about habit that increase the risks of
cancer.

175175
Behavioural modifications
 Cessation programs .
 Health education programs via schools, mass media,
etc
 Advocating healthy eating .
 All the age groups; both males and females should be
targeted.
 These programs do have an impact on modifying the
behaviours .

176176
Educational Approach
Tobacco Cessation Clinic
4 counseling sessions of 15 minutes for 4-6 weeks

177177
4 counseling sessions of 15 minutes for 4-6 weeks

178178
THE 5 ‘A’ EDUCATIONAL
APPROACH

179179
Smoking cessation proposed protocol for
the Dental office:

180180
Nicotine Dependence
 Affects mood and performance.
 Physical/psychological
dependency.
 Dopamine release – sense of well
being, reduced anxiety, cognitive
vigilance, arousing and relaxing
effects.
Withdrawal – irritation, impatience, restlessness,
Carbohydrate rich foods, weight gain, depressed mood

181181
Nicotine Replacement Therapy
 Nicotine replacement therapy when used for less than
eight weeks helped with withdrawal symptoms,
cravings, and urges (for example, transdermal
nicotine patches, gum, lozenges, sprays, and
inhalers).
 Nicotine replacement therapy doubles the smoker's
chances of quitting successfully.

182182
Pharmacotherapy
Weaning
doses
of nicotine
NICOTINE PATCH NICOTINE
CONTAINING GUMS

183183
Non-nicotine Medication
 Nicotinic receptor antagonist varenicline (Chantix)
(Champix in the UK).
Non-competitive
Nicotine
receptor
antagonist

184184
Secondary Prevention
Early detection of premalignant and malignant
lesions
 Screening
 Chemoprevention
 Oral self examination leads to greater reporting of
lesions

185185
 Screening involves early recognizing of abnormalities
and treating them appropriately.
 The main treatment modalities of oral cancer are
surgery and radiotherapy.
 Chemotherapy, which is currently used for advanced
or recurrent cancers, is not curative.

186186
Advances in Diagnosis
 Toluidine blue vital staining
 Fluoroscence spectroscopy: Fluorescence
visualization
 Oral brush biopsy
 Chemiluminescence
 Salivary Transcriptome Diagnostics
 Mitochondrial Resequencing Arrays
 Microfluidics

187187
Toludine Blue Vital Staining
 Metachromatic Dye Toluidine Blue
 High Risk Patients
 Dye has an affinity for nuclear material with a high
DNA or RNA content (dysplastic or malignant cells
within the epithelium).
 High sensitivity but low specificity - false positives-
trauma or inflammation.
 Restain any suspicious area in 2 weeks reduces the
number of false positives to fewer than 10%.
 It is very useful in the developing countries like India
because of the cost effectiveness and easy technique.
 Nowadays it is used along with Vizilite.

188188
Interpretation
Leukoplakia
stained with
toludine blue
 Dark Blue ( Navy Blue) Stain + Ve
 Light Blue Staining Doubtful.
 No Colour Negative Stain

189189
Fluoroscence spectroscopy
 Oral Cancer Tissue Auto fluoresecence compared to
normal tissue Protoporphyrin IX Red Fluorescence.
 Specific auto fluorescence emitted by cancer tissue
upon excitation with laser or xenon light have been
developed.
 Light at wavelengths of 337, 365, and 410 nm delivered
to the tissues discrimination between normal and
abnormal tissue.

190190
Fluorescence visualization
 At certain wavelengths, premalignant lesions of the
oral cavity show less fluorescence than surrounding
normal oral mucosa.
 It can be used not only as a screening tool but also as
a means of delineating the surgical boundaries in the
intraoperative setting.

191191
 The fluoroscence visualization (FV)
device - bench-top light source
coupled to a hand-held unit for direct
visualization.
 Lesions are illuminated by this
blue/violet light source
 Normal oral mucosa pale green
autofluorescence. defined as FV
retained (FVR).
 Tissue (malignant) which showed a
reduction in the normal pale green
and appeared as dark patches are
classified as FV loss.
 Marketed as VELscope.

192192
Oral Brush
Biopsy
 Any innocuous lesion.
 Marketed OralCDx kits
 Designed specifically to obtain a
complete transepithelial biopsy with
minimum discomfort to the patient.

193193
 The specimens are classified into 4 categories:
Negative/Atypical/Positive/Inadequate
 Positive predictive value of 30% to 38%
 High False Positive Rate Resulting In Unwarranted
Patient Anxiety And Biopsy.
 Possibility Of Obtaining A False Negative Report
 The slides modified Papanicolau method.
 The slides are scanned by the OralCDx computer system
 Images of abnormal cells identified by the computer
system are individually displayed on a high-resolution
color video monitor for final review by a pathologist.

194194
Chemiluminescence
 A chemiluminescent illumination system
to examine the oral mucosa is available
commercially as ViziLite.
 The technique is painless, and may ultimately identify
suspicious lesions missed during visual inspection
 Patient is asked to use 1% acetic acid as a 30 second
application or mouthrinse, which prepares the tissue.
 The light source is in a tube, which when bent,
activates the light for the oral inspection.

195195
Vizilight
Dysplastic
epithelium under
the blue-white
chemiluminescet
light appear
“acetowhite.”
Normal
epithelium, takes
on a blue hue.

196196
 Several benign oral lesions may be misinterpreted as
positive
 Recently ViziLitePlus has been introduced which
contains toluidine blue dye to assist in the further
evaluation of oral mucosal lesions for patients at an
increased risk for oral cancer.

197197
Salivary Transcriptome Diagnostics
 Salivary transcriptome diagnostics are
noninvasive diagnostic, prognostic, and
follow-up tests for cancer.
 Distinct m-RNA expression patterns like
IL1B, OAZ1 (Ornithine decarboxylase
antizyme 1), and IL8, can be identified in
saliva from cancer patients by RT-PCR/q-
PCR.

198198
 Although promising, the sensitivity (91%) and
specificity (91%) cannot meet the demands for being
a clinical tool for disease screening.
 Most important applications of the salivary
transcriptome diagnostics approach is to detect the
cancer conversion of oral premalignant lesions. The
overall malignant transformation rates range from 11
to 70.3%.

199199
Mitochondrial Resequencing Arrays
 TheMitoChip v2.0 mitochondrial genome
resequencing array can be used to detectminor
populations of mitochondrial DNA in salivary rinses
ofpatients with head and neck SCC.
 This techniquehas potential application in the
surveillance of patients afterresection and may have
applicability in the surveillance ofbody fluids in other
tumor types.

200200
Microfluidics
 The device, made of acrylic, has a small reaction
chamber fed and cleaned via tiny inlet and outlet
channels.
 A solution of scrapings from a patient's mouth enters
through the inlet and is strained through a cell-catching
filter.
 Researchers at the University of
Texas are developing a microfluidics
device that detects oral-cancer.
 It is simple and cheap enough for
use in the dentist's office.

201201
 Caught cells are then flooded with a solution
containing fluorescent protein tags.
 The tags stick to cancer biomarker, Under a
fluorescence microscope, cancer cells caught in the
device have an intense green halo. The entire test can
be performed in less than 10 minutes.
 Some labs are developing a small prototype machine
that incorporates both the microfluidics device and a
simplified fluorescence-imaging system.

202202
Onco-chips & Toxo-chips
 Onco-chips are the new concept consisting of several
reliable diagnostic head and neck cancer markers,
which may be used to diagnose cancer.
 A DNA Chip consisting of matrix-based comparative
genomic hybridization (matrix-CGH)with cancer
biomarkers which detects very minute changes in the
chromosomes by recording the fluorescent signals by a
laser-scanner.
 “Toxo chips”, contain the relevant probes to study cell
expression responses to chemical or drug insult, during
drug development. They can be used by
pharmaceutical companies.

203203
 The OFNASET is a handheld,
automated, easy-to-use
integrated system that will
enable simultaneous and rapid
detection of multiple salivary
protein and nucleic acid targets.
 This salivary biomarker detector
can be used in the office of a
dentist or another health care
provider for point-of-care
disease screening and detection.
Oral Fluid NanoSensor Test

204204
Chemoprevention
 Chemoprevention is a method of cancer control in
which the occurrence of disease is prevented by
administration of one or several chemical compounds.
– Vit A
– Selenium
– Phenols
 Trials have shown that a properly standardized dose
of B carotene / vit C / Vit E could reduce mean
proportion of buccal mucosal cells with micronuclei
in betel chewers.

205205
CHEMOPREVENTION
The administration
of agents, either
biologic or synthetic
leads to reversal of
premalignancy and
prevention of
secondary primary
tumors .
IFN, NSAIDS,
vitamin A analogs
such as beta-
carotene,
Isotretinoin
Vit E, Vit C
Natural agents like curcumin, Proteolytic enzymes Careseng
(ginseng derivative), less side affects.

206206
Tertiary prevention
 Surgery - Different surgery techniques are used to
remove specific types of oral tumors
 Radiation therapy - It is used to damage cancer cells
and halts the spread of cancer. Radiation therapy is very
localized, aimed at only the area where the cancer is
present. Radiation therapy may be administered
externally with a machine, or internally with radioactive
materials.
 Chemotherapy - this involves medications that kill
cancer cells. Chemotherapy has the ability to interfere
with the cancer cell replication, and may be used in
combination with surgery and radiation therapy.

207207
Rehabilitation of Patients with Oral
Cancer
 Surgical resections often
create large defects
accompanied by dysfunction
and disfigurement, and
radiation therapy produces
significant morbidity and
unique tissue-management
problems.

208208
 Speech, swallowing, control of
saliva, and mastication can all
be adversely affected. If these
cosmetic and functional
impairments are not corrected
or minimized, the patient may
be unable to resume a normal
working and social life.
 The primary objective of rehabilitation is the
restoration of appearance and function.

209209
 The various prosthesis used for rehabilitation are:
– The immediate surgical obturator
– The definitive obturator prosthesis
– The definitive soft palate prosthesis
 Secondary Surgical Procedures
– Vestibuloplasty, Tongue Release, and Skin Grafts
– Restoration of Mandibular Continuity

210210
 Physiology Of Oral Function Following Tongue
And Mandible Resection And Reconstruction
– Palatal Speech and Swallowing Aids
– Surgical Reconstruction of the Total Glossectomy
Defects
 Mandibular Guidance Therapy
 Removable Partial Dentures
 Complete Dentures
 Implant-Assisted Overlay Dentures
 Craniofacial Implants

211211
FUTURE OF CANCER PREVENTION
 Molecular Epidemiology  Understanding the Causes
of Cancer
 Promoting relationships between basic, clinical, and
population sciences
 Strategies and technologies that promote a multi-
disciplinary approach;
– to identifying risk factors
– underlying mechanisms
– studying the interaction of genetic and
environmental determinants of cancer risk
– shaping the design of preventive interventions

212212
 Integrative Cancer Biology
 Early Detection, Prevention, Prediction
 More integrated Clinical trials
 Bioinformatics

213213
The Ideal Public
Health Measures
Safe
Effective
Easy to use
Low in cost
Acceptable,
accessible,
affordable,
available,
accountable,
sustainable
Putting it all together for use in
Public Health Settings

214214
SUMMARY AND CONCLUSION
 Advanced oral cancer and its sequelae cause chronic
pain, loss of function, and irreparable, socially
disfiguring impairment.
 The functional, cosmetic, and psychological insults
suffered by oral cancer patients often result in social
isolation, significantly burdening patients, their
families and society.
 Ample evidence establishes the causal link between
use of tobacco products in any form and cancers of the
aerodigestive tract, based on extensive case-control
and cohort studies.

215215
 Of all the procedures available to control oral cancer,
none has affected survival as much as has Early
Detection.
 The oral cavity is easily accessible and an oral cancer
examination poses relatively little discomfort for the
patient. In addition, there is good evidence supporting
the effectiveness of counselling for smoking cessation.
 Oral cancer as a disease and its determinants has been
adequately described in literature and public health
programmes can be planned based on existing
evidence and disease distribution.

216216Our approach to public Health functions
HEALTH POLICY DEVELOPMENT
RESEARCH CYCLE

217217
RECOMMENDATIONS
 There is good evidence to include smoking cessation
counseling in the periodic health examination and
Inclusion of oral cancer screening in a periodic health
examination to prevent oral cancer.
 Further prospective studies are required to strengthen
the evidence demonstrating the effectiveness of
primary prevention strategies.

218218
 Further research should be directed to determining
whether current treatment modalities are in fact
effective in a well designed randomized controlled trial.
 Health care providers must assume more responsibility
to ensure that the public receives oral cancer
examinations on a routine basis.
 Both health care providers and the general public need
to increase their knowledge and change their behaviors
or practices - Health promotion is a key to achieving
these changes.

219219
Comprehensive Oral Cancer Prevention

220220
REFERENCES
 CDC Oral Cancer Background Papers
 Monique G. C. T. van Oijen and Pieter J. Slootweg;
Oral Field Cancerization: Carcinogen-induced
Independent Events or Micrometastatic Deposits?:
Cancer Epidemiology, Biomarkers & Prevention; Vol.
9, 249–256.
 Dr. Yick-Pang Ching: Molecular mechanism of
cancer metastasis.
• Moore SR, Johnson NW, Pierce AM, Wilson D. The
epidemiology of mouth cancer: a review of global
incidence. Oral Disease 2000;6:65–74.

221221
REFERENCES
 Carlo La Vecchia: Oral cancer: epidemiology, risk
factors and prevention.
 Peter S.; Essentials of Preventive and Community
Dentistry: 2nd
ed. 2003 p468-504.
 Government of India. Ministry of Commerce, Tobacco
Board. Available from URL:
http://www.indiantobacco.com/tboard/activities.htm
(Internet communication, 22 June 2001).
 Daftary DK et al. Oral Squamous Cell Carcinoma: In:
Diseases of the tropics. Prabhu SR et al: Oxford Univ
press, 1993; p 429 – 45.

222222
REFERENCES
 David M. Livingston; Ramesh Shivdasani; Toward
Mechanism-Based Cancer Care: JAMA. 2001;285(5):
588-593.
 Robert a. Ord, remy h., Blanchaert jr.; Current
management of oral cancer: A multidisciplinary
approach: JADA, Vol. 132, November 2001, Page no.
19S-23S.
 N. S. Murthy and Aleyamma Mathew; Cancer
epidemiology, prevention and control: CURRENT
SCIENCE, VOL. 86, NO. 4, 25 FEBRUARY 2004,
Page no. 518-27

223223
REFERENCES
 Professor Joerg Meyer, Josep Ramon Casas; oral
cancer detection using optical coherence tomography:
California-Catalonia Program for Engineering
Innovation 2007-2008 Progress Report
 Avi Zini: Epidemiology of Oral Cancer
 K. Ramadas: Screening for oral cancer: Experience in
developing countries

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