Oral Cancer Flashcards
What are the two patterns of oral cancer?
Oral cavity cancer
Oro-pharyngeal cancer
Each have their own populations, outcomes, and risks.
What is the estimated incidence of oral cavity cancer in the world population?
2.5 per 100,000
Who is at greater risk of developing oral cavity cancer?
Males more than females (2:1)
Smokers
Alcohol users
Lower socioeconomic status
Poor diet
By what factor do smokers increase their risk of oral cancer?
2 times
By what factor do drinkers (3-4/day) increase their risk of oral cancer?
2 times
By what factor do those who smoke and drink increase their risk of oral cancer?
5 times
What is happening to the rate of incidence of worldwide oral cavity cancer?
Decreasing in men, increasing in women, likely due to the reduction in tobacco use.
What is the estimated incidence of oro-pharyngeal cancer?
1.4 per 100,000
Male 4.8:1 Female
Generally increasing rates.
What impact does diet and health have to oral cancer risk?
There is limited data to support dietary factors such as low intake of fresh fruit/veg increases risk.
There is no known associated risk with obesity.
Why might socioeconomic status increase risk of oral cancer?
May be cause of smoking/drinking
Could also be lower education in population.
What is meant by the term dysplasia?
Dysplasia refers to the abnormal development of cells within tissues or organs. It can lead to various conditions that involve enlarged tissue, such as hip dysplasia.
What is meant by the term potentially malignant lesions?
Lesions that are en route to becoming cancer, much more likely to become cancer, or potentially malignant.
Which types of lesion are potentially malignant?
White lesions (leukoplakia)
Red lesions (erythroplakia)
Lichen planus
Oral submucous fibrosis
How would you identify a potentially malignant leukoplakia?
White patch does not rub off
Not linked to any other disease
How would you identify a potentially malignant erythroplakia?
Red lesion
Not linked to any other disease
What % of leukoplakia turn out to be malignant?
0.2-4% depending on timeframe
Which carries the higher dysplasia risk, erthyroplakia or leukoplakia?
Erythroplakia have a greater dysplasia risk, with around 50% of lesions already being a carcinoma.
However they occur much less frequently than leukoplakia.
How do you determine dysplasia of tissues?
Cellular atypia
Epithelial architectural organisation
How can dysplasia be categorised?
Low grade
High grade
Carcinoma-in-situ
What cytological cell changes can be seen in tissues with dysplasia?
Abnormal variation in:
Nuclear shape
Nuclear size
Cell size
Cell shape
Nuclear-cytoplasmic ratio
What architectural changes may be seen in tissues with dysplasia?
Irregular stratification
Loss of polarity of basal cells
Drop shaped rete ridges
Abnormal keratinisation
Loss of cell cohesion
Keratin pearls within rete ridges
What constitutes low-grade mucosal dysplasia?
Easily identifiable tumour
Considerable amount of keratin
Evidence of stratification
Well formed basal layer
What constitutes high-grade mucosal dysplasia?
Little resemblance to normal epithelium
Considerable atypia
Invade pattern with fine cords
What is carcinoma-in-situ?
A theoretical concept
Cytologically malignant but non-invading
Abnormal architecture
What is squamous cell carcinoma?
Carcinoma starting in the squamous cells of an epithelium.
Which histological factors can be used to indicate prognosis of an oral cancer patient?
Pattern of invasion
Depth of invasion
Perineural invasion
Invasion of vessels
What is the field cancerisation concept?
There is a higher risk of cancer in a 5cm radius of the primary lesion. This risk can be up to 15-20
How may patients present at stage I/II of oral cancer?
1/3 of patients.
What is the cure rate for stage I oral cancer?
80%
What is the cure rate for stage II oral cancer?
65%
If oral cancer progresses beyond stage II, what is the 5 year survival and cure rate?
<50% survival, <30% cure
What are the typical treatments for oral cancer?
Surgery
Radiotherapy
Chemotherapy
Immunotherapy
How would you identify lip cancer?
Non-healing ulcer or swelling
What are the two main risk factors for developing lip cancer?
Sunlight (UV)
Smoking
How do lip cancers develop?
Slow growth
Local invasion
Rarely metastasise to nodes
What aspects should be considered about screening for oral cancers?
Benefits v harm
Undetected lesions v false positives
cost of screening v cost of disease
cost of screening v harmful effects of disease
What screening tools are there for oral cancer?
HPV16 screening
Toluidene blue
VELscope
Photodynamic diagnosis
Clinical judgement
What are some drawbacks of using toluidine blue for oral cancer screening?
False positives in inflammatory lesions
~50% false negatives
What is the most effective and reliable oral cancer screening tool?
A trained GDP
What aspects of general practice are primary prevention for oral cancer?
Smoking cessation
Alcohol reduction
Healthy diet promotion