Week 1- Oral carcinogenesis and dysplasia Flashcards
What are characteristics of cancer?
- Invasive tumour
- Accumulation of mutations in DNA
- Disruption in cell proliferation, differentiation and development
- Abnormal, uncoordinated tissue growth
- Local tissue invasion and destruction
What is the most common primary oral cancer tumour?
Squamous cell carcinoma (>90%)
How do we recognise oral cancer?
- Oral Ulcerations (non-healing)
- Red or white patches
- Abnormal swellings
- Loss of Tongue mobility
- Cauliflower-like growths
- Abnormal, localised tooth mobility
- Non-healing tooth sockets
- Colour changes in mucosa
- Erosions in mucosa
- Reduced/altered sensation
What is a type of secondary oral cancer tumour?
Metastatic adenocarcinomas
What % of patients with oral cancer will die in next 5 years?
50%
What are the next most common primary oral cancer tumours?
- Minor salivary gland carcinomas
- Lymphoma
- Malignant melanoma
- Sarcoma
What causes SSC?
- Tobacco
- Alcohol
- Poor diet
- Infections (HPV, candida)
- Poor oral health
- Low SES
- Ageing
- Immunosuppression
- Genetic Predisposition
What does cannabis do to oral mucosa?
Increases permeability of oral mucosa. If you smoke and drink alcohol, you’re allowing those classic carcinogens to be more accessible to cells.
What are characteristics of normal oral mucosa?
- Stratified squamous epithelium
- Basal/spinous/granular/keratin
- Rete ridges
- Underlying dense CT lamina propria
- Masticatory/specialised/lining
What are the 3 epidermal proliferative units?
- Stem cells
- Amplifying cells
- Non-proliferative supra-basal cells
What happens if stem cell becomes over active?
They can become tumour initiating stem cells. (this process can be halted/reversed before progressing to cancer)
What happens when cells switch to malignancy?
- Immortalisation and neurovascularisation
- Cell migration
- Local invasion and metastasis
What is oral epithelial dysplasia?
Histopathological term describing a spectrum of Tissue Dysmaturation & Disorganisation changes seen in biopsy specimens
What are cytology histopathological features of oral epithelial dysplasia?
- Variation in Nuclear Size and Shape
- Variation in Cell Size and Shape
- Increased Nuclear to Cytoplasmic Ratio
- Atypical Mitotic Figures
- Increased Number & Size of Nucleoli
- Hyperchromasia
What are tissue architecture histopathological features of oral epithelial dysplasia?
- Irregular Epithelial Stratification
- Loss of Polarity of Basal Cells
- Drop-Shaped Rete Ridges
- Increased Number of Mitotic Figures
- Abnormally Superficial Mitoses
- Premature Keratinisation in Single Cells (Dyskeratosis)
- Keratin Pearls within Rete Ridges
