Clinical Investigations—Histopathology Flashcards
Definition of BIOPSY:
Definition:
- removal of TISSUE/FLUID from a LIVING person
- for DIAGNOSTIC purposes
To know:
- biopsy is the least ambiguous, is the ‘gold’ standard
(If from dead person is an autopsy)
Collection methods of Biopsy:
- incional/excisional biopsy
- Using punch/scalpel
- Cut at edge to get some intact epithelium for comparison
- Excisional
- Incisional (curettage, punch)
- Fine needle aspiration
- Smear
- Exfoliative cytology (some labs can look at scrapes, which are unreliable in nature)(u do this when u are not rdy to cut out the tumour)
What is the difference of excision and incision?
Excision - complete removal of tumour
Incision - partial removal of tumour, just making a cut
Incision is preferred for biopsy cuz
1. Less invasive
2. Easier to find margins later to ensure complete removal
When to do a biopsy?
- When lesion persists for >2 weeks w no apparent cause
- Inflammatory lesion doesnt respond to local tx aft 2 weeks
- Keratotic changes persists
- Visible or palpable tumescence beneath normal tissue is present
- Lesions interfere w local function
What are some characteristics that raise suspicion of malignancy
- Ulceration of >2 weeks
- Bleeding on gentle palpation
- Induration (thickening n hardening)
- Erythroplasia
- Fixation
- Rapid growth rate
What are 2 ways of incisional biopsy?
- Curettage (aka scraping, but this is not reliable and not done often anymore)
- Punch (more reliable)
When u do a biopsy, what else do you try to include?
Normal tissue
- so that pathologist can also compare
Name the types of aspirates..
- Pus: e.g. ‘sulphur granules’
- Keratin (cheesy stuff).. H&E stained film shows keratinized squamous
- H&E stained film shows keratinised squamous
- Straw colour fluid: radicular & dentigerous cysts
- Blood: haemorrhagic tumour
What do immunofluorescence tests identify?
- identify autoantibodies produced & tissues they target
