Dysplasia and Oral Cancer Flashcards
What are the high risk sites for mouth cancer?
Floor of the mouth
Lateral border of the tongue
Retromolar regions
Soft and hard palate
Gingivae
Buccal mucosa
What 3 sites are more predisposed to developing squamous cell carcinoma in drinkers and smokers?
Lateral border of the tongue
Floor of the mouth
Soft palate
What is smokers who don’t drink alcohol risk for developing oral cavity cancer?
x2 risk
Increased with quantity, duration and frequency of tobacco use
Fewer cigarettes for longer duration worse than high number, short term
Smoking risks were generally greater for larynx cancer
What is people who drink alcohol but have never smoked risk for developing oral cavity cancer?
x2 risk
Frequency is more important than duration- more drinks each day is key
Alcohol drinking for oral cavity and pharyngeal cancers
What is an individuals oral cavity cancer risk if they smoke and drink alcohol?
x5 risk
Increases with frequency and duration of smoking and alcohol consumption
No safe lower limit
What is an individuals oral cavity cancer risk if they have a poorer socioeconomic status?
x2 risk
Eve without other risk factors
Low education attainment
SIMD- 4 & 5 at highest risk
What effect does stopping smoking and drinking have on reducing the risk of oral cancer?
Benefits of quitting smoking were identified within 1 to 4 years after stopping smoking
Risks reduced and reached a similar level to those who had never smoked after 20 years of quitting
In contrast, the risk effects associated with quitting heavy alcohol consumption take 20 years to begin to emerge
Quitting smoking is much more beneficial in the short term rather than quitting alcohol in terms of cancer risk
What are some potentially malignant lesions?
Leukoplakia
Erythroplakia
Lichen planus
–candidal leukoplakia
–chronic hyperplastic candidiasis (angular cheilitis)
Oral submucous fibrosis
How are tumours classified histologically?
Low grade, high grade and carcinoma-in-situ
Based on cytological and architectural changes
What is dysplasia?
A way of assessing cancer risk
What is dysplasia based on?
Cellular atypia
Epithelial architectural organisation
What is a low-grade dysplasia defined as?
Easy to identify that the tumour originates from squamous epithelium
Architectural change into lower third
Cytological atypia or dysplasia may not be prominent
Shows a considerable amount of keratin production
Evidence of stratification
Well formed basal cell layer surrounding the tumour islands
Tumour islands are usually well defined and are often continuous with the surface epithelium
Invasion pattern with intact large branching rete pegs ‘pushing’ into underlying CT
What is high-grade dysplasia defined as?
Shows little resemblance to a normal squamous epithelium
Architectural change in the upper third
Usually shows a considerable atypia
Invade in a non-cohesive pattern with fine cords, small islands and single cells infiltrating widely through the CT
Mitotic figures are prominent and many may be abnormal
What is the concept of ‘Field Cancerisation’?
Where a cancer develops inside the mouth is not the only part of the mouth that has been subject to the changes and stimuli which has led to cancer
Same changes can be progressing in other parts of the mucosa at a slower rate but may at some stage in the future also produce oral cancer, this would be a new primary rather than recurrence
Field cancerisation tells us that any patient presenting with dysplasia or carcinoma has a risk of developing further tumours in other parts of the mucosa- High cancer risk in 5cm radius of original primary, that is most of the mouth/pharynx
What are metachronous lesions?
Cancers which develop subsequent to the original lesion but from the same field change and same interaction between genetic and environmental factors
