Histopathology and Cytopathology Flashcards
What do histo- and cytopathologists study?
Histopathologists – Tissues
Cytopathologists - Cells
Where might histopathology and cytopathology might be used as a diagnostic method?
Definitive diagnosis of diseases on tissue level – e.g Certain cancers and their stage and grade
Also used to monitor treatment and course of disease – E.G IBD
What are biopsies and what can they tell pathologists?
Small samples of tissue taken via needles.
Search for any change from normal tissue – E.G Inflammation or malignancy
What is a resection specimen and what can they tell pathologists?
A larger section of tissue is removed and used for investigation (may also be presented with biopsies of other areas to check for metastases)
Used to provide definitive diagnoses, see extent of tumours and likelihood entire tumour has been removed. Also provide information for most useful treatment plans
What is a frozen section and when are they taken and used?
Frozen sections can be used in time-intensive settings E.G A patient still currently undergoing surgery and masses found, it can be determined in benign or malignant and needs removal while the patient is still anaesthetised. (Changes course of operation)
What are the advantages and disadvantages of Frozen section?
Advantages -
Quick
If information does change surgery plan the patient will not need another surgery with associated risks
Disadvantages -
Expensive
Time consuming
Patient will be under anaesthetic for longer duration while being processed (with associated risks)
When are post-mortems used?
To gather in-depth definitive information over a patient’s death
When are smears used?
Cervical smear tests are routinely used in adult women to look for signs of malignancy or pre-malignancy in those who had been exposed to HPV (It is expected that due to the HPV vaccines smear tests will eventually become less routine)
What are fine needle aspirates and when are they used?
Collection of small samples of cells – Can study individual cells and search for signs of cancer, inflammation or other dysfunction (works well with solid and liquid samples)
How are histopatholgy sections obtained?
Specimens are labelled carefully, fixed in formalin and embedded in paraffin wax. From there the specimen can be cut to obtain sections.
What is done with sections?
The conventional stain applied to the sample is haematoxylin & eosin (Pink stain)
Other stains include gram stain and Ziehl-Neelsen stain (for tuberculosis) – If you suspect TB then specifically ask for the Z-N stain to be taken (Blue stain)
Specific antigens can be identified using antibodies (immunohistochemistry)
Other molecular tests
How long does it take clinicians to receive results for pathology sample?
Frozen sections: 30 minutes
Biopsies: 2-3 days
Resection specimens: 5-7 days
