Lecture 5- Oral biopsies and histology of normal oral tissues Flashcards
(41 cards)
What is a biopsy?
Removal/sample of tissue to assess the histological assessment, diagnosis and therapy
What types of biopsy are there?
Incisional biopsy Excisional biopsy Frozen section Fine Needle Aspiration Cytology (FNAC) Direct Immunoflourescence
What is an incisional biopsy?
For diagnostic reason, takes the sample and normal tissue
What is an excisional biopsy?
Takes all of the abnormal area ( often malignancy) Is prognositc May need adjunctive therapy or re excision
What do you do with the sample as soon as you have taken it?
FIX it! Fix using Formal saline We do this to prevent - putrefactions - Drying autolysis It also aids the staining
What then happens to the specimen?
Technician-Booking in Pathologist- Cut up (trimming) Technician- Specimen embedding Technician- Microtome sectioning Technician- H+E Staining Pathologist- examines Technician- Levels/special stains/ immunohistochemistry Pathologist – reporting Secretaries- typing Pathologist- check and dispatch the report
What does Eosin stain?
Eosinphillic Keratin, Muscle, bone (un calcified), collagen, most cytoplasm.
What does heamatoxylin stain?
Basophillic Nuclie ( RNA/DNA) Bone Plasma MPs (ground substance)
What stain is this?
H&E
What stains mucins, glycogen and fungi?
PAS/D Periodic Acid schiff
What stains bacteria? and some fungi
Gram stain
What stains mycobacteria?
Ziehl Neelsen
What stains amyloid
Congo red
What stain is this?
Insert pic
what is immunohistochemistry?
monoclonal antibodies bind to antigens on sample. These can produce an antibody profile and shown the origin of the tissue
What is a frozen section
Rapid freezing for immediate results, (used to make sure you have excised all the margins in theatre) Gives results in 30 mins.
Why isn’t frozen section used all the time?
As its poor quality.
What is FNAC?
Aspiration of a lesion through a needle and spread onto a slide as a monolayer for examination. Can see cell structure and morphology but not architecture
When is FNAC used?
the one stop neck clinic. Where there is a surgeon, a radiologist and a pathologist. Guided by ultrasound and processd chair side. Gives patient same day results. Its purpose is to side track patient with head and neck cancer.
What are the advantages of using FNAc
Low cost, speed of diagnosis,negligible complications of it.
Disadavantages of FNAC
Because the tissue architecture cannot be visualised you cannot always get a definitive diagnosis.
When is immunofluresence used
For vesicullobullous disorders.Uses antibodies to target antigens on cells. Targets are visualised with a fluorescent microscope
What is direct immunoflouresence?
Patient’s tissue Labelled animal immunoglobulin(antiserum/antiglobulin)
What is indirect immunoflouresence?
Patient’s serum (immunoglobulin) Animal tissue Labelledanimalimmunoglobulin(antiglobulin)
