Dysplasia Flashcards
What are the high risk sites for oral cancer?
FOM
Lateral border of tongue
Retromolar region
Soft and hard palate
Gingivae
Buccal mucosa
What are the risk factors for oral cancer and oropharyngeal cancer?
Smoking, betel quid chewing
- Increases with frequency, duration and quantity of tobacco used.
Alcohol- frequency more important than duration
UV exposure
Poor diet
Low socioeconomic status
Oropharyngeal cancer- HPV-16
- Sexual activity- six or more lifetime partners
- Four or more oral sex partners
- Early age of sexual debut
What are the chances of a white lesion turning into cancer?
Varied reports- most under 4%.
2.5% in 10 years, 4% in 20 years.
What type of mucosa do most oral carcinomas develop from?
Normal mucosa- not necessarily from what or red lesions.
Why is there a higher risk of malignant transformation of red lesions than white?
Red lesions suggest a change in vascular supply- i.e. increased vascular proliferation.
This process occurs in cancer.
What is dysplasia?
Disordered maturation in a tissue.
Can only be detected by means of a microscope- not a clinical diagnosis.
What is cellular atypia?
Describes changes in cells.
What is meant by the term potentially malignant lesion?
Altered tissue in which cancer is more likely to form.
Give examples of potentially malignant lesions.
Chronic hyperplastic candidosis
Proliferative verrucous leukoplakia
Erythroplakia
Leukoplakia
What is Chronic Hyperplastic Candidosis?
Persistent red/white speckled lesion caused by Candida albicans.
Where is chronic hyperplastic candidosis usually found?
Commissures of the mouth and sometimes the tongue.
Presents as a mixed red and white lesion, triangle shaped in the commissures of the mouth going posteriorly onto the buccal mucosa.
What cohort of patients usually have chronic hyperplasticity candidosis?
Smokers
Iron and folate deficiencies
Immune cell-mediated depletion
What does chronic hyperplastic candidosis look like clinically?
Found in the anterior commissures of the mouth
Discrete raised lesions that vary from small, palpable, translucent, whitish areas to large, dense, opaque plaques, hard and rough to the touch (plaque- like lesions)
Non-homogeneous
Speckled
If you suspect chronic hyperplastic candidosis, what would you do?
Refer for incisional biopsy of the lesion for histological analysis and periodic acid shiff stain.
Need to determine whether there is dysplasia present (histology) and also if there is candida species present (PAS).
What does chronic hyperplasticity candidosis look histologically?
Parakeratosis
Acanthosis
Inflammatory cells within the lamina propria- macrophages, lymphocytes and plasma cells.
Intra-epithelial invasion of immune cells
Margination and emigration of polymorphs from blood vessels into the tissue.
Hyperplastic epithelium
Mitotic figures higher up the epithelium than what is expected- usually only in the basal cell membrane.
What would the PAS show in chronic hyperplasticity candidosis?
Candida should stain pink- lots of glycogen in the cell walls of candida.
According to the literature, what is the risk of malignant transformation of chronic hyperplastic candidosis?
9-40%
What treatment should be done for chronic hyperplastic candidosis?
Smoking cessation and alcohol advice- educate the patient about why these are risks actors.
Biopsy and if it is mild dysplasia or higher- excise the whole lesion.
Systemic Fluconazole- 50mg one capsule a day for 14 days.
Ensure review regularly.
What factors influence the prognosis of chronic hyperplastic candidosis?
Risk factors, such as tobacco and alcohol use
Whether the lesion is speckled (more dangerous) or
homogeneous
The presence (more dangerous) and degree of epithelial
dysplasia
The management adopted.
How likely is a leukoplakia to turn to a malignancy?
50 to 100 times more than normal mucosa.
What factors make it more likely for a leukoplakia to develop into a malignancy?
Older age
Site- FOM or lateral border of tongue are high risk sites
Non-homogenous- verrucous, ulcerated, leuko-erythroplakia.
What is the gold standard for determining whether a leukoplakia is likely to become malignant?
Biopsy and histopathological analysis.
Look for
- Dysplasia
- Atrophy of the epithelium
- Candida infection
What molecular markers might be used to determine oral epithelial dysplasia?
Signalling pathways- EGFR
Cell cycle- p53, pRB
Immortalisation- Telomerase
Angiogenesis- VEGF
COX1 and 2
HPV +ve
What classification is used to grade dysplasia?
WHO classification 2005
Basal Hyperplasia
Mild
Moderate
Severe
Carcinoma in situ
What is the criteria for diagnosis of dysplasia?
Architectural changes - abnormal maturation and stratification
Cytological abnormalities- cellular atypia
Describe basal hyperplasia?
Increased basal cell numbers
Architecture- regular stratification, basal compartment is larger.
No cellular atypia
What is mild dysplasia?
Architectural changes in the lower third
Mild atypia- pleomorphism, hyperchromatism, basal cell hyperplasia
Mitotic figures higher up than in the basal cell membrane.
What is moderate dysplasia?
Architectural changes seen into the middle third
Moderate atypia- pleomorphism, hyperchromatism
What is a severe dysplasia?
Architectural changes extend into upper Thord
Severe atypia- pleomprhism, hyperchromatism, loss of polarity of nucleus, numerous mitosis abnormally high.
What is carcinoma in situ?
Abnormal architecture in full thickness of the epithelium.
Pronounced cytological atypia- mitosis abnormalities frequent.
Cytologically malignant but not invading.
Clinically may appear red and ulcerated- epithelium is thin.
Describe the grading system of low, high and carcinoma in situ?
Low grade
- architectural change into lower third
- Cytological atypia or dysplasia may not be prominent
- Considerable amount of keratin formation- parakeratosis
- evidence of stratification
- Well formed basal cell layer
High
- Little resemblance to a normal squamous epithelium
- architectural change in the upper third
- considerable atypia
- invade in a cohesive pattern with fine cords, small islands and single cells infiltrating widely through the CT
- Mitotic figures are prominent.
What cytological factors would suggest dysplasia?
Abnormal variation in cell size, cell shape, nuclear size, nuclear shape, nuclear hyperchromatism, atypical mitosis figures, increased/altered nuclear-cytoplasmic ratio.
What architectural features would suggest dysplasia?
Irregular epithelial stratification
Loss/disturbed of polarity of basal cells
Drop-shaped rete pegs
Increased and abnormal mitoses
Abnormal keratinisation
Keratin pearls within rete pegs
What are histological prognostic factors?
Invasion of vessels- associated with metastasis- poorer prognosis.
Perineural invasion
Depth of invasion of tissue
Pattern of invasion
What oral cancer screening tools are available at the moment?
Vital staining- Toluidine blue, stains particular markers of the cel blue- not specific.
Oral cytology
Optical imaging- Velscope
HPV16 screening
Salivary biomarkers- research for the future.
What is the molecular basis of cancer?
Altered gene expression, leads to altered cell function.
What are the 6 factors that make up the hallmarks of cancer?
Self-sufficient growth signals
Insensitivity to anti-growth signals
Tissue invasion and metastasis
Limitless replicative potential
Sustained angiogenesis
Evading apoptosis
State some of the OSCC subtypes.
Basaloid squamous
Spindle cell
Verrucous carcinoma
