oral potentially malignant disorders

Question 1

what is an OPMD

Answer 1

group of lesions and conditions in oral mucosa that display increased risk of malignant transformation

Question 2

name 3 (4) OPMDs

Answer 2

leukoplakia
(proliferative veruccous leukoplakia)
oral erythroplakia
oral submucous fibrosis

Question 3

oral leukoplakia
- epidemiology
- clinical features
- histology

Answer 3

epidemiology: 6x more prevalent in smokers, 2% prevalence gloabally
clinical: white lesion that cannot be scraped off
histology: various degrees of keratinisation, dysplasia may or may not be present

Question 4

proliferative veruccous leukoplakia
- epidemiology
- clinical features

Answer 4

epi: F>M, elderly
clinical: veruccous, non homogenous appearance, resistant to treatment, high recurrence

Question 5

oral erythroplakia
- epidemiology
- clinical features
- histology

Answer 5

epi: 50s-60s, 0.2%
clinical: flat or slightly depressed red patch, common sites = FOM, lateral tongue and soft palate
histology: epithelial dysplasia is common

Question 6

oral submucous fibrosis
- epidemiology
- clinical features
- histology

Answer 6

epi: south asia and india, areca nut/betel quid, 10s-30s
clinical - progressive fibrosis of submucosal tissues - burning, stiffness, limited mouth opening, blanching
histology: fibrosis and hyalinisation in lamina propria

Question 7

name 4 clinical risk factors of a lesion for malignancy

Answer 7

size - >200mm2
site - lateral tongue, soft palate, FOM
texture - non homogenous
colour - red or speckled

Question 8

name 4 patient risk factors for malignant change

Answer 8

50+
female
drinks alcohol
previous head and neck cancer

Question 9

what is dysplasia

Answer 9

abnormal cells or abnormal cell changes within a tissue

Question 10

how is dysplasia graded

Answer 10

mild - lower 1/3 only
moderate - middle 1/3
severe - more than 2/3
carcinoma in situ - full thickness affected

Question 11

name 4 architectural features of epithelial dysplasia

Answer 11

loss of polarity of basal cells
loss of epithelial cell cohesion
increased number of mitotic figures
drop shaped rete ridges

Question 12

name 4 cellular features of epithelial dysplasia

Answer 12

abnormal mitotic figures
nuclear pleomorphism
cellular pleomorphism
hyperchromatism

Question 13

screening

Answer 13

tool to identify a developing cancer in a patient who may have increased risk

early detection is vital for decreasing morbidity and mortality

Question 14

discuss vital staining with toluidine blue

Answer 14

screening aid for OPMDs
tolonium chloride as metachromatic dye
mucosa rinsed with acetic acid twice then dye applied
binding of blue dye means positive result

(significant number of false positives, may be used to help choose biopsy site)

Question 15

optical fluorescence imaging

Answer 15

e.g VELscope
disruption to tissue morphology in dysplasia and cancer alters their fluorescence
normal tissues will appear bright green, abnormal tissues dark green

Question 16

oral brush cytology

Answer 16

minimally invasive approach for harvesting cells
requires good technique to ensure cells from each layer are harvested

Question 17

is there any pharmaceutical medications for OPMDs (to prevent progression to malignancy)

Answer 17

no - no robust evidence
systemic vitamin A and NSAIDs have been suggested

Question 18

surgical treatment of OPMDs

Answer 18

1st choice treatment is excision with cold steel
full excision of OPMD with few mm margin

if malignancy 1cm margin required