Dysplasia & Oral Cancer Flashcards
What can potentially malignant disorders be subtyped into
- potentially malignant lesion
- potentially malignant condition
What is a potentially malignant lesion
altered tissue in which cancer is more likely to form
What is a potentially malignant condition
- generalized state with increased cancer risk
What are examples of potentially malignant lesions/conditions
- leukoplakia
- erythroplakia
- lichen planus
- oral submucosa fibrosis
- iron deficiency
- teritary syphilis
LP, OSF, tertiary syphilis can be potential malignant lesion/condition
What are predictors of malignancy in luekoplakia
- age
- gender
- site
- clinical appearance
How does age effect risk of malignant transformation of leukoplakia
older px more likely
How does gender effect risk of malignant transformation of leukoplakia
- female more at risk
How does site effect risk of malignant transformation of leukoplakia
- buccal mucosa = low risk
- FOM & tongue = high risk
- sublingual keratosis occurs in FOM and is v high risk
How does clinical appeareance effect risk of malignant transformation of leukoplakia
- homogenous vs non-homogenous surface
- non-homogenous higher risk
What is a homogenous surface
same colour and consistency throughout lesion
What is a non-homogenous lesion
*e.g verrucous, ulcerated, leukoerythroplakia
should be biopsied
Which types of lichen planus are at most risk of malignant transformation
- erosive/atrophic
- lichen planus also at greater risk of developing candidal leukoplakia which increases risk of malignant transformation
What is oral submucous fibrosis
- more common in china and india
- linked to betel nut chewing
- abnormal collagen is deposited in connective tissue in submucosa
- results in fibrosis of tissues and muscles
- limited mouth opening
- produces epithelial atrophy and sometimes leuko/erythroplakia
- 8% malignant transformation
How does iron deficiency increase risk of malignant transformation
- oral epithelium thins
- protection lost against carcinogens
What is tertiary syphilis
- get gumma formation
- can result in leukoplakia on tongue
- high risk for transformation to SCC
What is the gold standard for assessing malignant potential
biopsy (histopathology)
What are the tissues assessed for in histopathology
- dysplasia
- atrophy
- candida infection
- biological markers (mostly in research atm)
What are some of the biological markers that are looked at
- DNA content
- p53
- HPV
What does increased DNA contnet in leukoplakia suggest
biological marker in histopathology
- cell is acquiring hallmarks of cancer
What is p53
- guardian of the genome
- activates when cell damage occurs
What does p53 do when there is cell damage
- stops cell cycle to allow DNA repair
- apoptosis where repair is not possible
What is often discovered about p53 in cancers
- it has been inactivated
- by mutation or by virus (oncogenic)
Which types of HPV are associated with oropharyngeal cancer
mainly type 16
also hpv 18 occasionally
What is dysplasia
disordered growth in a tissue