7. The etiology is unknown. But a
number of etiological factors have been
implicated.
Strong Association:
•
Tobacco smoking and chewing
•
Chronic alcohol consumption
•
Human papilloma virus infection
8.
9. Major
source of intra-oral carcinogen.
All forms of tobacco consumption have been
linked.
South east Asia: bethel quid– North Africa
and Middle East: a mixture of Tobacco and
lime water or oil called naswar or nash
It could be held in the mouth
Smoked in crude cigars or factory made
cigarettes
Carcinogens in tobacco: Nitrosamine
(nicotine), the polycyclic aromatic
hydrocarbons (3,4-benzopyrene)
10. 2nd major risk factor
Associated with cancer of the floor of the mouth
and tongue.
Excess consumption of EVERY TYPE of
alcohol(including “hard” liquor, wine, and Beer)
raises the risk status of oral cancer
Potentiates the effects of tobacco
Mechanism(s)
Dehydrating effects of alcohol on the mucosa
increasing mucosal permeability,
Irritation of mucosa
and it also acts as a solvent for
carcinogens(especially those in tobacco)
11.
12. Weak association:
Chronic irritation from ill-fitting denture
Sub mucosal fibrosis
Poor orodental hygiene
Nutritional deficiencies
Exposure to sunlight(lip cancer)
Plummer –Vinson syndrome
13. NEOPLASIA:The
process of transformation
from a normal cell to a cancerous one.
An
abnormality of cell growth and
multiplication characterised by:
At cellular level
Excessive cellular proliferation
Uncoordinated growth
Tissue infiltration
At molecular level
Disorder of growth regulatory genes
14. NEOPLASTIC (malignant) CELLS
Increase
in growth
factors
Increase
in growth
factor
receptors
Increase in
signal
transduction
- Disturbed processes of mitosis and protein synthesis
Increase in
activation of
transcription
15.
Continuous reproduction
Formation of abnormal proteins
ANAPLASIA:
loss of normal cell function (abnormal DNA transcription)
proliferation
movement of cells
Caused by altered DNA and altered
invasion of nearby tissue
cellular programs which make new
metastasis
signals
16. two
Monoclonal
general types
initial neoplastic change affects a single cell
Field origin
carcinogen acts on large number of cells producing
field of potentially neoplastic cells
18. - code for factors that down-
regulate the cell cycle, promote
differentiation and supress
oncogenes from causing cancer
Rb-1 – retinoblastoma gene
p53
19. NEOPLASIA proto-oncogene is activated or
tumor suppressor gene is inactivated
normal growth oncogenesis
Activation of proto-oncogene:
point mutation
translocation
gene amplification
Also - Failure of Immune Surveillance theory :
immune system responds to neoantigens as to foreign
antigens, but neoplastic cells escape recognition and
destruction --> become clinical cancers
20.
Transmission of some forms of cancer from parents to
offspring through defects in the DNA of the egg or sperm cells
E.g. Retinoblastoma – tumor of the retina of the eye
Polyposis coli syndrome – polyps that grow in the
colon and
rectum
Other colon, breast and kidney cancers
Cause: loss of a segment of DNA or a change in the coding
sequence of DNA
Detection – DNA sequencing, DNA probes
In many cases – abnormalities in tumor suppressor genes
21.
22. A sore in the mouth that does not heal (most
common symptom)
Pain in the mouth
A persistent lump or thickening in the cheek
A persistent white or red patch on the
gums, tongue, tonsil, or lining of the mouth
A sore throat or a feeling that something is
caught in the throat
Increased salivation
23. Difficulty chewing or swallowing
Difficulty moving the jaw or tongue
Swelling of the jaw that causes dentures to
fit poorly or become uncomfortable
Loosening of the teeth or pain around the
teeth or jaw
Voice changes
A lump or mass in the neck
Weight loss
Persistent bad breath
24. Grossly, squamous cell carcinoma of
oral cavity may have the following types:
Ulcerative type
Papillary or verrucous type
Nodular type
Scirrhous type
All these types appear on a background of
leukoplakia or erythroplasia of the oral
mucosa.
Enlarged cervical lymph nodes may be
present.
27.
Primary:
Photographs
Incisional biopsy
Fine needle aspiration biopsy
Orthopantogram
Mucosal staining
CXR
chemiluminescent light
Routine blood investigations
For staging
MRI
CT face + neck ± CT chest
USG of neck or primary ± USG guided FNAC of suspicious
lymphadenopathy
PET
Endoscopy
28.
29.
Surgery
Removal
Removal
of part or all of the jaw
of the tumor on a larger area to remove the
tumor and surrounding healthy tissue
Maxillectomy
Removal of lymph nodes and other tissue in the neck
Plastic surgery, including skin grafts, tissue flaps or
dental implants to restore tissues removed from the
mouth or neck
Tracheotomy, or placing a hole in the windpipe, to
assist in breathing for patients with large tumors or
after surgical removal of the tumor
Dental surgery to remove teeth or assist with
reconstruction
30. Radiation Therapy
-used alone to treat small or early-stage
tumors.
Proton Therapy
-delivers high radiation doses directly into the
tumor, sparing nearby healthy tissue and vital
organs.
Chemotherapy
-used to shrink the cancer before surgery or
radiation
Tumor Growth Factor Inhibitors
-target EGF receptors and may stop cancer
cells from growing.
31. Mucositis ,an inflammation of the mucous
membranes in the mouth.
Infection, pain, and bleeding
Dehydration and malnutrition due to dysphagia
Xerostomia due to injury to the glands that
produce saliva.
Trismus due to damage to the muscles and joints
of the jaw and neck.
Hypovascularization (reduction in blood vessels
and blood supply.
Affect other forms of dental disease (caries, or
soft tissue complications),
Cause bone death (osteonecrosis).
32. Rehabilitation
of patient after surgery could
be either surgical reconstruction, prosthetic
reconstruction or both
This is aimed at restoring esthetics, function
and speech.
All patients must be placed on life-long
review of about 6monthly intervals during
which risk factors should be continually
assessed.
33.
34.
35. Prevention involves interventions aimed at
eliminating, eradicating or minimizing the
impact of the disease.
PRIMARY: Reduce the incidence of cancer and
precancer. It is aimed reducing the number of
new cases.
Discourage
smoking and alcohol consumption
Encourage good oral hygiene
Encourage balanced diet
Use of hat in sunlight for farmers
Wearing of facemasks for factory workers involved
with chemicals and metals
Health education
36. SECONDARY:
aimed at detection of cancer
atan early stage.
Early detection, especially at the
precancerous stage, offers a better prognosis
with a better chance of cure.
Public
education on early signs and selfexamination
Screening
TERTIARY:
Treat late stage of disease and
complications