Pathogenesis of the Head and neck 2

Question 1

At what point does severe dysplasia become invasive dysplasia?

Answer 1

Once the cells have crossed the basement membrane and have invaded the surrounding tissue are they deemed as an invasive malignancy.

Question 2

Dysplasia

Answer 2

1. Premalignant process
2. Can be identified in many tissues
3. Epithelia are a good example (squamous, glandular).

Question 3

Epithelial dysplasia

Answer 3

Atypical epithelial alterations limited to the surface squamous epithelium.
Architectural changes - maturation and differentiation.
Cytological changes - changes in cells.

Question 4

What does dysplasia indicate?

Answer 4

Risk of developing a carcinoma

Question 5

Describe the cells seen in epithelial dysplasia?

Answer 5

Cells show abnormal features that are also seen in cancer cells but they do not yet possess the ability to invade adjacent normal tissues.

Question 6

Histological features of epithelial dysplasia

Answer 6

1. Nuclear and cellular pleomorphism
2. Alteration in nuclear/cytoplasmic ratio (invariably an increase)
3. Nuclear hyperchromatism
4. Prominent nucleoli
5. Increased and abnormal mitoses

Question 6

Histological features of epithelial dysplasia (11)

Answer 6

1. Nuclear and cellular pleomorphism (variable size/shape)
2. Alteration in nuclear/cytoplasmic ratio (invariably an increase)
3. Nuclear hyperchromatism
4. Prominent nucleoli
5. Increased and abnormal mitoses
6. Loss of polarity of basal cells
7. Basal cell hyperplasia
8. Drop-shaped rate pegs i.e. wider at their deepest part
9. Irregular epithelial stratification or disturbed maturation
10. Abnormal keratinisation (dyskeratosis - cell starts to keratinise before the surface is reached)
11. Loss/reduction of intercellular adhesion.

Question 7

All of the features of oral epithelial dysplasia may be seen in oral squamous cell carcinoma, however in dysplasia…

Answer 7

the atypical cells are confined to the surface, in SCC the atypical cells invade into the underlying connective tissue.

Question 8

Epithelial dysplasia WHO 2017 grading

Answer 8

Mild
Moderate
Severe (or carcinoma in situ)

Question 9

WHO grading: mild

Answer 9

Disorganisation, increased proliferation and atypic of basal cells

Question 10

WHO grading: moderate

Answer 10

More layers of disorganised basaloid cells, atypic, supra basal mitoses

Question 11

WHO grading: severe

Answer 11

Very abnormal, affects full thickness of epithelium

Question 12

Oral potentially malignant disorders

Answer 12

Oral mucosal lesions that have a potential risk of developing into oral SCC.

Not all lesions considered to have equal risk

Not all lesions will undergo malignant transformation

Question 13

WHO examples of oral potentially malignant disorders

Answer 13

Question 14

Answer 14

Oral submucous fibrosis

Question 15

Answer 15

Chronic hyperplastic candidosis