OM- Potentially malignant disorders

Question 1

Compare a potentially malignant lesion to a potentially malignant disorder?

Answer 1

Potentially malignant lesion- altered tissue in which cancer is more likely to form.
Pottentially malignant disorder- a generalised condition which puts patients at greater risk of cancer.

Question 2

List some potentially malignant conditions

Answer 2

Leukoplakia (undiagnosed white patch)
Erythroplakia (undaiagnosed red patch)
Lichen planus- erosive and ulcerative type are higher risk.
Chronic hyperplastic candidasis
Tertiary syphillis-
Iron deficiency- causing thinning of oral epithelium.
Oral submucous fibrosis- abnormal collagen produced inthe submucosa which causes limited mouth opening (caused by chewing the betel nut)
Iron deficiency.

Question 3

What clinical test do we complete with a white patch and what does the result tell us?

Answer 3

Try and scrape the lesion off.
If it scrapes off it is a candidal lesion.
If it does not scrape off it is leukoplakia.

Question 4

What is leukoplakia?

Answer 4

A white patch that cannot be diagnosed clinically. It is a pottentially malignant lesion which is 50-100 x more likely to progress into cancer than clinically normal mucosa.

Question 5

Give some clinical predictors of malignancy

Answer 5

Age (more likely when older)
Gender (females are more likely)
Idiopathic (patients without risk factors are more likely)
Site (floor of mouth & tongue = high risk. Buccal mucosa = low risk. Sublingual keratosis= very high risk.
Clinical appearance- Non-homogeneous e.g. verrucous/ ulcerated leuko-erythroplakia = increased risk.

Question 6

What are we looking for when taking a biopsy of a suspected leukoplakia?

Answer 6

Dysplasia
Atrophy
Candida infection

Question 7

What is chronic hyperplastic candidiasis?

Answer 7

This is candidal leukoplakia which is associated with smoking and has an increased risk of progressing into oral cancer.

Question 8

Compare epithelial dysplasia and cellular atypia?

Answer 8

Dyplasia is disordered growth in the tissue.
Atypia is disorded growth in the cell.

Question 9

What architectural changes are we looking for in the biopsy ?

Answer 9

How much of the epithelium is involved (1/3? 2/3?)
Stratification- are the cells arranged normally?
Any spaces between the cells
Atypia (pleomorphism and hyperchromatism)

Question 10

Compare hyperchromatism and pleomorphism

Answer 10

Pleomorphism - change in nuclei size.
Hyperchromatism- change in cell staining as a result of DNA retention in the cell.

Question 11

Name and grade this type of dysplasia?

Answer 11

Basal cell hyperplasia
Increase in the number of basal cells causing a larger basal compartment.
Architecture- regular stratification
Cytology- no atypia.

Question 12

Name and grade this type of dysplasia?

Answer 12

Mild dsyplasia
architecture- changes in the lower 1/3 (Basal cell hyperplasia)
Cytology- Mild atypia. Pleomorphism. Hyperchromatism

Removal of the cause can help it regress.

Question 13

Name and grade this type of dysplasia?

Answer 13

Moderate dyplasia
Architecture-change extends in to the middle third. There are spaces between the cells. The rete ridges become rounder.
Cytology- Pleomorphism and hyperchromatism.

Question 14

Name and grade this type of dysplasia?

Answer 14

Severe dysplasia
Architecture- changes extend to the upper third (we have loss of stratification)
Cytology- Severe atypia and numerous mitoses (mitoses are not at the bottom which is abnormal)

Question 15

Name and grade this type of dysplasia?

Answer 15

Carcinoma in situ
Theoretical- Malignant but not invasive (all cells have shown malignant change but haven’t spread to the underlying connective tissue)
The connective tissue should show inflammation (good immuen response)

Archiecture- abnormal all viable cell layers involved
Cytology- Pronounced cytological atypia with mitotic abnormalities.

Question 16

How do we detect oral cancer?

Answer 16

Clinically then histopathologically for confirmation (Biopsy)

Question 17

What are the two main factors involved in carcinogenesis?

Answer 17

Genetic and carcinogens (environmental factors)

Question 18

Name the 6 hallmarks of cancer?

Answer 18

Self-sufficency in growth signals

Question 19

What important information is provided with a biopsy

Answer 19

Grading and differentiation (is it a well/moderately or poorly differentiated carcinoma)
Pattern of invasive front (Can help predict if lymph nodes are involved)
Spread (local extension/ Lymphatic spread/ haematogenous spread )

Question 20

What type of cancer are the majority of oral cancer?

Answer 20

Oral squamous cell carcinoma

Question 21

Compare cohesive and non-cohesive front’s in terms of oral cancer patterns?

Answer 21

Cohesive front- the malignant lesion progresses as one.
Non-cohesive front (The malignant lesion progresses in small clumps- this has a positive correlation with lymph node involvement)

Question 22

Why do we biopsy a leukoplakia?

Answer 22

To exclude carcinoma and assess for candida colinization.

Question 23

What do we use to grade dysplasia?

Answer 23

Cytological changes
-Abnormal variations in nuclear size, nuclear shape, cell size, cell shape, Atypical mitotic figures.
Architectural changes
-How much of the epithelium is involved? Irregular epithelial stratification.Loss. disturbed polarity. Drop shaped rete ridges. Increased and abnormal mitoses. Premature keratinisation in single cells. Abnormal keratinisation. Keratin pearls within the rete ridges.

Question 24

What is the most common malignancy related to oral cancer?

Answer 24

Oral squamous cell carcinoma

Question 25

What histological factors can be used to predict prognosis?

Answer 25

• Pattern of the invasive front (helps us predict if lymph nodes are involved)
• Spread

Question 26

What are we looking to find out about the spread of a malignancy?

Answer 26

Is there local extension (to the mucosa/tongue/bone nerve)
What is the depth of invasion (greater risk for tumours >4mm depth)
Has it spread to lymphatics
Any haematogeneous invasion (Widely associated with lymph node metastases and a poor prognosis)
Any perineural invasion (especially if found in nerves far away from the cancer site.

Question 27

What is chronic hyperplastic candidasis?

Answer 27

This is a white lesion associated with the candidal organism and smoking. (pottentially malignant condition)