Dysplasia and Oral Cancer

Question 1

what are the 2 distinct disease patterns of oral cancer?

Answer 1

• oral cavity cancer
• oro-pharyngeal cancer

Question 2

which sex is more commonly affected by oral cavity cancer?

Answer 2

Male 2:1 Female

Question 3

what are the high risk sites for mouth cancer?

Answer 3

• floor of mouth
• lateral border of tongue
• retromolar regions
• soft & hard palate
• gingivae
• buccal mucosa

Question 4

which area of the world is oro-pharyngeal cancer most commonly seen?

Answer 4

North America and South Central Asia

Question 5

What condition is thought to be associated with oro-pharyngeal cancer?

Answer 5

HPV

Question 6

what affect does smoking and drinking have oral cavity cancer?

Answer 6

• smokers who don’t drink 2x risk
• drinkers (3/4 drinks/day) who don’t smoke 2x risk
• smoke & drink… 5x risk

Question 7

what risk factors are associated with oral cancer?

Answer 7

• smoking
• alcohol
• betel quid (paan)
• socioeconomic status
• family history
• diet

Question 8

what are examples of potentially malignant lesions?

Answer 8

• white lesions
• red lesions
• lichen planus
• oral submucous fibrosis

Question 9

what type of white patches tend to be potentially malignant?

Answer 9

leukoplakia

Question 10

what is erythroplakia?

Answer 10

• red patch
• more likely to be malignant

Question 11

are white or red patches more likely to be cancerous?

Answer 11

red lesions more likely

Question 12

what might suggest that a white lesion is malignant?

Answer 12

• non-homogeneous (variation within lesion)
• atrophic background

Question 13

what is dysplasia risk based on?

Answer 13

• cellular atypia
• epithelial architectural organisation

Question 14

how are dysplastic lesions categorised?

Answer 14

• low grade
• high grade
• carcinoma in situ

Question 15

how are dysplastic lesions classified into either low-grade or high-grade risk?

Answer 15

based on cytological and architectural changes

Question 16

what is meant by Cytological changes in dysplastic lesions?

Answer 16

Changes in individual cells reflecting abnormal DNA content in the nucleus, failure to mature and keratinise correctly and increased proliferation.

Question 17

Give some examples of cytological changes seen in dysplastic lesions:

Answer 17

• abnormal variation in nuclear size or shape
• abnormal variation in cell size or shape
• increased/altered nuclear-cytoplasmic ratio
• atypical mitosis figures
• increased number & size of nucleoli

Question 18

Give some examples of architectural changes seen in dysplastic lesions:

Answer 18

• irregular epithelial stratification
• loss/disturbed polarity of basal cells
• drop-shaped rete ridges
• increased & abnormal mitoses
• premature keratinisation in single cells
• abnormal keratinisation

Question 19

what are some features that are present in a low-grade dysplasia?

Answer 19

• easy to identify that tumour originates from squamous epithelium
• considerable amount of keratin production
• well formed basal cell layer
• tumour islands usually well defined & often continuous with the surface epithelium

Question 20

what are some features that are present in a high-grade dysplasia?

Answer 20

• show little resemblance to a normal squamous epithelium
• usually show considerable atypia
• mitotic figures are prominent

Question 21

what is meant by carcinoma-in-situ?

Answer 21

cytologically malignant but not invading

Question 22

what histological prognostic factors suggest that a lesion is potentially malignant?

Answer 22

• Pattern of invasion = widely infiltrating small islands & single cells
• Depth of invasion = greater that 4mm more likely to metastases
• Perineural invasion
• Invasion of vessels

Question 23

what does the concept of “field cancerisation” refer to?

Answer 23

high cancer risk in 5cm radius of original primary cancer lesion (most of mouth & pharynx in oral cases)
- mouth must be continually reviewed after discovery of original cancer lesion

Question 24

how is oral cancer staged?

Answer 24

Based on:
- site
- size (T)
- spread (N&M)

Question 25

what is the % cure rate for a stage I oral lesion?

Answer 25

80% cure rate

Question 26

what is the % cure rate for a stage II oral lesion?

Answer 26

65% cure rate

Question 27

what treatment is used in patients with oral cancer?

Answer 27

• surgery
• radiotherapy
• chemotherapy / immunotherapy

Question 28

what is the aetiology of lip cancer?

Answer 28

• sunlight UV-B
• smoking

Question 29

what is commonly used by dentists in oral cancer detection?

Answer 29

Oral Cancer Recognition Toolkit

Question 30

what are some examples of oral cancer screening?

Answer 30

• HPV screening
• Toluidine blue
• VELscope
• Photodynamic Diagnosis (PDD)
• Clinical judgement of experienced clinician

Question 31

what is Toluidine blue?

Answer 31

dye that is applied to oral mucosa that stains markers in cells (dysplasia & trauma areas)
- good for invasive disease

Question 32

what is VELscope?

Answer 32

Autofluorescence of tissues with blue light
- loss of fluorescence equates to change

Question 33

how fast should patients be referred to local max-fax pathway if dentist feels a lesion may be cancerous?

Answer 33

2 week rule