Dysplasia and Oral Cancer Flashcards
What is the international classification of Oral Cancer?
- ICD-O
International classification of disease for Oncology
What are the 2 distinct disease patterns of OC?
- Oral cavity cancer (OCC)
- Oro-pharyngeal cancer (OPC)
What is the epidemiology for Oral cancer?
- Highest in Scotland for OCC and OPC compared to rest of UK
- Makes higher than females for both in all of UK but that is decreasing 2:1
What are the high risk sites for Oral Cancer?
- Floor of mouth
- Lateral border of tongue
- Retromolar regions
- Soft and hard palate
- Gingivae
- Buccal mucosa
The rates are rapidly rising for Oro-pharyngeal cancer what is this linked to>
- Linked to rising HPV epidemic
What are the risk factors for Oral Cancer?
- Smokers who don’t drink x2 risk
- Drinkers 3-4 drinks/day X2 risk
- Smoke and drink x5 risk
- Betel quid x3 risk
- Socioeconomic status x2 risk
Inregard to oral cancer what are we uncertain have an effect on predisposition?
- Family history
- Oral health
- Sexual activity (may be due to HPV)
What are the benefits to stopping smoking and drinking?
- Benefits of quitting smoking shown within 1 - 4years after stopping
- Risk reduced to sim level to those who had never smoked after 20yrs quitting
- Quitting alcohol takes about 20yrs to show
What are Potentially malignant lesions?
- The correct terminology for lesions that might be considered cancerous
- Small chance of actually becoming malignant
What are some potentially malignant lesions>
- White/red mixed patches
- Lichen planus
- Candidal leukoplakia
- Chronic hyperplastic candidiasis
- Oral submucous fibrosis
Is erythroplakia or leukoplakia more likely to become malignant?
- Erythroplakia
What is the categorisation of Dysplasia we use today?
- Based on Cellular atypia
and Epithelial architectural organisation
WHO guidelines 2005
Mild dysplasia - only affects basal third
Moderate dysplasia = affects basal and middle third
Severe dysplasia = affects basal, middle, and top third
Carcinom-in-situ
What is meant by cytological findings that classify oral mucosa dysplasia?
- These are changes in individual cells reflecting abnormal DNA content in nucleus, failure to mature and keratinise correctly and increased proliferation
What cytological findings classify the histological grading of oral mucosa dysplasia?
- Abnorm variation in nuclear size
- Abnorm variation in nuclear shape
- Abnorm variation in cell size
- Abnorm variation in cell shape
- increased/altered nuclear-cytoplasmic ratio
- Atypical mitosis figures
- Increased number and size of nucleoli (prominent nucleoli_
- Nuclear hyperchromatism
What is meant by Architectural findings in the histological grading of Oral mucosa Dysplasia?
- Changes in the organisation of maturation and normal layering of epithelium
What are the Architectural findings that can be found in histological grading of oral mucosa dysplasia?
- Irregular epithelial stratification
- Loss/disturbed of polarity of basal cells
- Drop-shaped rete ridges
- increased and abnormal mitoses
- Premature keratinisation in single cells
- Abnormal keratinisation
- Keratin pearls within rete ridges
- Loss of epithelial cell cohesion or adhesion
What are the findings for Low grade Oral mucosa dysplasia?
- 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 are the findings for High-grade oral mucosa dysplasia?
- Show little resemblance to a normal squamous epithelium
- Architectural change upper third
- Usually show 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 meant by the term Carcinoma in situ?
- Theoretical concept
- Cytologically malignant but not invading
*Abnormal architecture
Full thickness (or almost full)
Severe cytological atypia
*Mitotic abnormalities frequent
What are the histological prognostic factors that are helpful in deeming severity?
- Pattern of invasion of rete pegs
- Depth of invasion as 4mm x 4mm greater than tumours of less
- Perineural invasion (seen in 60% of OSCC)
- Invasion of vessels
What is the field cancerisation concept?
- Pt who presents with dysplasia or malignancy has chance of devloping malignacy in other parts of mucosa
- Due to fact that all parts of the mucosa have been exposed to the cancer risk not just the section that has shown as cancerous right now
What are synchronous lesions?
- Lesions that have arisen at the same time as other lesions
What are metachronous lesions?
- Develop subsequent to original lesion even many months later but are due to the same field cancerisation as the original lesion
What are the variables assessed for clinical staging of oral cancer?
- Site
- Size (T)
- Spread (N&M)
What is the survival of stage I and stage II oral cancer?
- Stage I 80%
- Stage II 65%
- If left untreated with metastases survival 4 months
What is aetiology of Lip cancer?
- Usually lower lip non-healing ulcer or swelling
- Sunlight UV-B and smoking
- Behaviour is slow growth, local invasion , rarely metastasise to nodes
- Good prognosis if early detection
What considerations are important when seeing if oral cancer screening are useful ?
- Benefit vs harm
- Undetected lesions vs false positives
- Cost of screening vs cost of disease
- Cost of screening vs disability from disease
Give some examples of Oral cancer screening methods?
- HPV16 screening
- Toluidene blue
- VELscope
- PDD (Photodynamic diagnosis)
- Clinical judgment of experienced clinician
What primary prevention should a GDC do at oral examinations?
- Smoking cessation
- Healthy diet
- Alcohol reduction
What is the time frame a lesion suspected of cancer should be seen?
- 2 weeks from referral
- 62 days from referral to txt time for pts with cancer
