Biopsy Flashcards
What is a biopsy
- sample of tissue for histopathology analysis
What is the function of a biopsy
- confirm or establish a diagnosis
- determine prognosis
What are the different tissue sampling techniques
- Aspiration - can be a blood sample or from a lesion
- Fine needle aspiration
- Excisional
- Incisional
What is the advantages of an aspiration biopsy
- avoids contamination by oral commensals
- protection from anaerobic species
- may also aspirate cystic lesions
- aspiration will determine whether lesion is solid or fluid filled
- occasionally it may yield blood - haemangioma
What is a fine needle aspiration biopsy
- aspiration of cells from solid lesions
What is an excisional biopsy
- remove all clinically abnormal tissue
When should we use an FNA biosy
- e.g neck swellings, salivary gland lesions
- cytology
When do we do excisional biopsies
- usually fairly confident of provisional diagnosis
- usually benign lesions e.g fibrous overgrowths, denture hyperplasia, mucoceles
- discrete lesions
What is an incisional biopsy
- representative tissue sample
When do we use an incisional biopsy
- larger lesions
- uncertain diagnoses
- e.g leukoplakia, lichen planus, SCC
Why may you want to leave some of an SCC post biopsy
if its positive for SCC
surgeons need to go back in and clear margins
will be easier for them to see if its partly there
What is a punch biopsy
- type of incisional
- removes core tissue
- minimal damage
- sometimes get away with no sutures
- comes as 4,6,8mm
What should samples be placed in prior to sending to lab
10% formalin
How should we take care of the specimen
- sutures - can be useful for orientation
- biopsy is fragile
- filter paper - to reduce sample distortion
How should we choose an area to biopsy
- choose a representative sample
- try to avoid salivary gland duct orifices, tip of tongue, areas close to nerves and large BV
What are fordyce spots
- Sebaceous glands in underlying mucosa
- doesnt need biopsied
What is a fibropeithelial polyp
- frictional irritation or trauma
- semi pedunculated or sessile
- pink
- smooth surface
- most common buccal mucosa and inner surface of lip
- can be excised
What is a haemangioma
- looks like small grapes
- collection of BV
- hamartoma
- developmental overgrowth
- blue in colour
- pressure causes blanching
- surgical removal or cryotherapy
What is a pregnancy epulis
- histologically same as pyogenic granuloma
- may be related to calculus
- bleed easily
- hormonal changes enhance response to tissue irritation
- small lesions may not require excision and may regress after birth
- larger lesions should be excised
What is a squamous cell papilloma
- benign neoplasm
- white surface
- usually pedunculated
- cauliflower appearance
- similar to viral warts
- excision at base required
What is denture hyperplasia due to
poorly fitting denture
What is a leaf fibroma
- due to chronic irritation from denture
- associated with dentures in palate
- polyp
- would be round if not covered by denture but is flattened
- pedunculated
- excision
What is a mucocele
- mucous extravasation cyst
- most common minor salivary gland problem
- damage to minor gland duct - saliva leaks into submucosa layer
- soft bluish swelling fluid filled
- recurrent
- called a ranula in FOM
What is the classic squamous cell carcinoma description
- ulcer
- rolled margin
- induration
- lesion may bleed easily and be fixed to surrounding issue
