Cytology and Cytopathology Flashcards
Define cytology
Study of cells under light microscopy
Give some examples of methods of acquiring cells
(3)
Cells can be exfoliated, scraped (brushing) or aspirated
Fine needle aspiration -> cells from a solid legion e.g. a benign or malignant legion
Brushing e.g. for cervical cells
What is cytopathology
Microscopic examination of cells from the body for the diagnosis of disease
A branch of pathology that deals with manifestations of disease at the cellular level
Two divisions: cervical and diagnostic
What are the two divisions of cytopathology
(2)
Cervical (gynae)
- cervical smears
Diagnostic (non-gynae)
- everything other than cervical smears
- can get ovarian cyst fluid which is technically still gynae so ‘diagnostic’ is used instead
Write about the history of cytology - cervical
(6)
George Papanicolaou carried out research on hormonal cycle in rats and then extended this on the human menstrual cycle
He looked at hormonal changes in cervical cancer
He identified cell changes that were pre-clinical i.e. asymptomatic
Identified morphology of cervical carcinoma
Used immediate fixation to retain cellular detail
Developed the Papanicolaou staining procedure for cervical and diagnostic cytology
Write about Papanicolau’s publications
Used drawing of cells as pictures weren’t taken
Didn’t know what he was drawing or what was causing it e.g. tadpole cells
He was ahead of his time
Republished in the 1950s
Precursor to the cervical screening program
What is Liquid Based Cytology and why was it introduced?
Implementation of LBC for cervical screening allowed for residual sample to be used for research
Clinician used to swab cervix with wooden spatula and then smear cells
The spatula was thrown in the bin and the slide was fixed
Most of the cells were lost in the bin
The slide often had artefact as it wasn’t fixed correctly
Now we use LBC and a brush to get the cells and transfer them straight to liquid broth
We can get the cells out of the brush in the lab so we don’t waste any
We also have a more controlled, cleaner preparation of cells
What are the benefits of liquid based cytology
(5)
Further understanding of HPV associated with cervical cancer
Development of HPV testing
Implementation of primary HPV testing for cervical cancer screening programme
No artefacts in sample e.g. blood
Correct fixation - no air drying
Who was the first to use FNA?
(4)
First used in the Karolinska Institute (1940 to 1970’s)
Lost favour in US but continued in EU
Now widely accepted as a diagnostic tool
No complications of biopsy or surgery
What is diagnostic cytology
(3)
A diagnostic tool
Not screening
Allows diagnosis to be made based on cellular features
Give some examples of extra-cellular features which can be used in a diagnosis in diagnostic cytology
Nuclear
Cytoplasmic
Architectural
Extra-cellular
- Colloid
- Amyloid
- Lympho-glandular bodies
Give three methods of staining used in diagnostic cytology
Routine staining methods
Histochemistry
Immunohistochemistry
What are the two routine staining methods in diagnostic cytology
Pap stain
May-Grunwald Giemsa
What are the three histochemistry stains used in diagnostic cytology
Grocott’s silver
Congo Red
D/PAS
What is the most common sample in the diagnostic cytology lab?
Exfoliated cells
Where can cells be exfoliated from?
(4)
Cyst fluid
Body cavity fluids
Sputum
Urine
What three methods allow access to deeper lesions in diagnostic cytology
Endoscopy
FNA
Endoscopic ultrasound
What specimens can be achieved from an endoscopy
Bronchoscopy specimens
e.g. bronchiole brushings or saline wash
What specimens can be achieved from a FNA
Cells from a solid lesion
e.g. trans bronchiole FNA -> through bronchus into the legion in the wall
How can endoscopic ultrasound be used in diagnostic cytology
CT guided FNA
Lymph nodes
Pancreas
Where is FNA very commonly used?
Veterinary practices
how can FNA be used with CT guidance?
Place in the guide wire
Check CT to see if guide wire is in the legion
Proceed with needle
What is FNA?
Cells are aspirated from a solid lesion using a fine needle under negative pressure (vacuum) and processed for microscopic examination
What is cytopathology?
First-line diagnosis
What is involved in first-line diagnosis?
(7)
Reactive
Inflammation
Infection
Neoplasia
- Benign
- Malignant
- Metastatic
Why are ancillary techniques important
They have an extended role in diagnostics, prognostics and therapeutics
Give four examples of applications of ancillary tehcniques
Cell blocks
Immuncyto/histochemistry: Her2 histochemistry
Flow cytometry
Molecular: ISH/DNA/RNA analysis
What is ISH
In-situ hybridisation
What is the diagnostic algorithm in diagnostic cytology
(4)
Routine stain -> what disease process is going on
Immunohistochemistry -> Primary or secondary? is it benign or malignant? Panels if malignant
Grading and staging if malignant
IHC (for therapeutic markers) and/or molecular
What should be done if immunohistochemistry indicates a secondary tumour?
(2)
Need to find the primary site to identify the tumour
Is the tumour well differentiated e.g. does it clearly look like breast. If undifferentiated need to carry out a larger panel to ID the tumour type
What is meant by cancer staging
(2)
Low stage means a primary cancer i.e. tumour found in tissue where it is usually found e.g. cancer of the lung involving lung tissue
High stage e.g. carcinoma in lymph node -> indicates metastasis
Who reports cytopathology
Cytopathologist
Sometimes histopathologise
What training programmes are currently under way for medical scientists in the UK
(2)
Training for medical scientist to report
But there is some resistance from pathologists here in Ireland but this is being done in the UK
What are the advantages of cytology
(5)
Less invasive sampling e.g. FNA vs biopsy
Faster turn around times -> no formalin fixation overnight
Ancillary techniques
Metastatic disease -> FNA, fluid cytology
Patient management
What are three limitations of cytology
Sample size/cell yield
Experience/expertise
Assessment of invasion
