Oral Cancer Flashcards
What does hypertrophy mean?
Increase in cell size
What does hyperplasia mean?
Increase in cell number
What does atrophy mean?
Reduction in cell size by loss of cell substance
What does hypoplasia mean?
Reduced size of an organ that never fully developed to normal size
What does metplasia mean?
Reversible change in which one adult cell type is replaced by another adult cell type
What does dysplasia mean?
Abnormal growth
What does neoplasia mean?
New growth
In adult tissues what is the size of cell population determined by?
The rates of cell proliferation, differentiation and death by apoptosis
What is meant by the term apoptosis?
Programmed cell death
What are the 2 main classifications of tumours?
Behaviour
Histogenesis
What are the 2 types of behaviour tumours?
Benign
Malignant
What is a prognosis?
Prediction of the probable course and outcome of a disease.
Appropriate treatment and estimated survival
What does a cancer prognosis involve?
Tumour type
Tumour grade
Tumour stage
What classification is used for staging malignant tumours?
TNM
What does TNM classification stand for?
T- extent of primary tumour
N - absence or presence and extent of regional lymph node metastasis
M - describes the abscence or presence of distant metastasis
What is distant metastasis?
Cancer that has spread from the original (primary) tumour to distant organs or distant lymph nodes
Define the term oral cancer
The general term given to the variety of malignant tumours that develop in the mouth
What is the most common tumour that counts for 90% of all cancers of the mouth?
Squamous cell carcinoma
What area of the mouth is concerned when talking about mouth cancer?
Anterior (2/3) of the tongue
What area of the mouth is concerned when talking about oropharyngeal cancer?
Posterior (1/3) of the tongue
What is the largest risk factor for mouth cancer?
Tobacco
What is the second largest risk factor for mouth cancer?
Alcohol
What age group does oral cancer mostly effect?
> 55
If you smoke >21 cigarettes and consume over 7 ounces of alcohol per day how much does your risk of developing mouth cancer increase by?
24%
How does alcohol contribute to mouth cancer?
It causes thinning of the overlying mucosa making it more permeable for the carcinogens to enter the epithelial cells
If you smoke <10 cigarettes a day what is your risk compared to a non smoker of developing cancer?
2.5 x
If you smoke <20 cigarettes a day what is your risk compared to a non smoker of developing cancer?
5.0 x
If you smoke >20 cigarettes a day what is your risk compared to a non smoker of developing cancer?
5.5 x
If you quit smoking how long does it take for your relative risk to fall down to the same as someone who has never smoked?
20 years
Why does smoking cause cancer?
Contains the chemicals nitrosamines and acrolein (mutagen, carcinogen?
What is an example of a cultural habit associated with an increased risk of mouth cancer?
In Asia a lot of the population use betel nuts
What is oral submucous fibrosis?
abnormal collagen deposition
What does excessive alcohol consumption do to the metabolic pathway for oxidation of ethanol?
Slows it down, preventing acetaldehyde from converting to acetate
What is the recommended alcohol consumption per week in units?
14
How long does it take the body to eliminate 1 unit of alcohol?
1 hour
How can a poor diet contribute to mouth cancer?
Insufficient levels of supplements such as iron can cause the mucosa to become thinner making it more permeable for carcinogens
What is the known carcinogen in alcohol?
Ethanol is broken down into acetaldehyde
What is the third largest risk factor for mouth cancer?
Infection of HPV (Human Papilloma Virus)
What are the 5 types of HPV?
Alpha
Beta
Gamma
Mu
Nu
Which type of HPV most commonly effects the oral mucosa?
Beta
Which high risk HPVs are associated with mouth cancer?
HPV16 abd HPV18
What group does HPV belong to?
Papovavirus group
What does oncogenic mean?
causing development of a tumour or tumours
What early genes does HPV consist of?
E1-E7
What late genes does HPV consist of?
L1 and L2
What early genes give HPV its ocogenic properties and why?
E6 and E7 because they target the tumour suppressor genes and knockout their function
Why does HPV target cells which are capable of dividing?
Because the virus wants to take over the genetic regulation and production of proteins of the cell
Which protein does E7 interact with to inactivate the human tumour suppressor gene product?
The retinoblastoma protein (pRB)
Which protein does E6 bind to for the destruction by the ubiquitin pathway?
p53
What are the 2 main benign oral HPV lesions?
Papilloma
Condylomata
What is the most common malignant oral HPV lesion?
Cancer - Squamous Cell Carcinoma (SCC)
Does mouth cancer generally give patients symptomatic or asymptomatic lesions?
Asymptomatic
What can happen to the teeth within a cancerous lesion?
They can become mobile
What does it mean for an area of the mouth to be indurated?
Hard and rubbery to touch
What percentage of oropharyngeal cancers are HPV related?
Up to 80%
What are the 2 main risk factors behind HPV?
Number of sexual partners
Weakened immune system
What are the 3 HPV vaccines?
Quadrivalent Gardasil
Bivalent Cervarix
Nonvalent Gardasil
What is the Epstein-Barr Virus (EBV)?
A type of Herpes virus
What does EBV most commonly cause?
Infectious mononucleosis
What is infectious mononucleosis more commonly known as?
Glandular fever (kissing disease)
What is a common oral symptom of a HIV positive patient?
Oral candidiasis
What is Kaposi’s sarcoma?
A rare type of cancer that affects the skin, mouth and occasionally the internal organs
What are usually the first symptoms of Kaposi’s sarcoma?
Red, purple or brown patches, plaques or nodules on the skin
Where is commonly effected by UV Light as a risk of mouth cancer?
Lower lip
Approximately 20% of mouth cancers have HPV within tumour cells, which HPV does this tend to be?
HPV16
What is the commonest oral lesion with a viral aetiology?
Papilloma
What is the known national screening programme for oral cancer?
There isnt one
What are the 3 types of prevention classified into?
Primary
Secondary
Tertiary
Define primary prevention and what is the role of the clinician here?
Prevents a disease from developing
Giving risk factor education - e.g. smoking/alcohol consumption
Define secondary prevention and what is the role of the clinician here?
To detect disease while it is localised or ‘early’
Screening the oral cavity - looking for what is normal/abnormal
Define tertiary prevention and what is the role of the clinician here?
to mitigate the morbidity from established disease and to improve quality of life
maintaining oral health and remaining dentition after patients have been treated/undergoing treatment. Also giving advice regarding risk factors
What are the 3 screening programme types?
Mass
Selective
Opportunistic
What screening programme is used in dentistry?
Opportunistic
For a screening programme to be successful what must it be high in?
Sensitivity and Specificity
How is sensitivity calculated?
True Positive/TP+False Negative
How is specificity calculated?
True Negative/TN+FP
What % of specify and sensitivity in a screening programme is acceptable
80 or more
What is the best way to screen for oral cancer?
Conventional oral examination
What is the name of the only study to have shown benefit of screening oral cancer?
Cochrane Review
What does OPMD stand for?
Oral potentially malignant disorders
Name a common OPMD
Lichen planus
What is meant if something is homogeneous?
uniform/normal in colour, content, texture
Are white or red lesions more worrying?
Red
what sites in the mouth are at the highest risk for developing mouth cancer?
FOM and lateral borders of tongue
What does leukoplakia mean?
clinical term that means a white patch, isn’t easily removed with gauze, no obvious risk factors (a white patch of unknown cause)
What is the clinical term used to describe red lesions of an unknown cause
Erythroplakia
What is meant by endophytic?
Inwards growing
What is meant by exophytic?
Outwards growing
When can cancers become painful?
When they are secondarily infected or when they invade nerves
What is meant by a perineurial spread?
Cancerous cells that have invaded the nerves
What is meant by a vascular invasion?
When cancerous cells have invaded the blood supply
How is the size of a lesion recorded?
In T sizes
How big is a T1 lesion?
<2cm
How big is a T2 lesion?
2-4cm
How big is a T3 lesion?
4-6cm
How big is a T4 lesion?
> 6cm or if it involves bone
What should you do if you spot a suspicious lesion?
Photograph /document in notes
Eliminate trauma
Review
Refer using urgent pathways
What is sensitivity of a screening programme telling you?
The proportion of the population who are correctly classified as having the disease
What is the specificity of a screening programme telling you?
The proportion of the population correctly classified as disease-free
When examining a patients lymph nodes what are you looking for?
Symmetry
Soft non tender lymph nodes
Palpate all anatomical sites of lymph nodes
Skin moves freely over the nodes they are not attached
think about anatomical drainage from the mouth to the nodes of the neck
Symmetrical salivary glands
