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Flashcards in Cytology Deck (27)
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1
Q

What are the advantages of cutology?

A
  • quick, easy, inexpensive
  • Non-invasive and minimal risk to patient
  • used as a screening tool to determine what diagnostic procedures should be performed next
  • useful in Dx or IDing disease process
2
Q

What are the limitations of cytology?

A
  • Reliant on sample quality (skill of collecter, smear quality, type of tissue [exfoliation], site of collection)
  • Experience/ability of person examining sample and quality of microscope
  • Lack of information about tissue architecture (histopath provides this)
  • Dx challenges of cytology
3
Q

How does histopath compare to cytology?

A
  • more expensive procedure as sterile
  • slower turnaround (48hrs)
  • poor detail for round cell tumours (cytology better)
  • tissue architecture visable, tumour grading, immunohistochemistry more available
4
Q

What samples can be analysed by cytology?

A
> Aspiration or imprints 
- superficial masses
- LN enlargement/metastitis 
- Organs and deep masses with US guidance 
> Fluids 
- body cavities (peritoneum, pleural space, pericardium) 
- Joints
- Respiratory tract (TTW, BAL) 
- Cerebrospinal fluid
5
Q

What are FNA/Bs used for?

A

solid/fluid filled masses

  • biopsy = aspirate but no negative pressure applied [no need really]
  • aspirate may be carried out only if biopsy not successful (ensure remove negative pressure on plunger before removing from mass or contents will be sucked into syringe)
  • only fill needle part of syringe, if fluid reaches syringe will probably be blood stained
  • necrotic centre masses = ensure wall is sampled as well as centre
6
Q

What are the goals of smear preparation?

A
  • Thin areas with good cell spread
  • Minimise cell damage
  • Minimise blood content
7
Q

Which cells are most suceptable to rupture if excessive pressure is applied when making a smear?

A

Neoplastic cells AND lymphocytes

8
Q

What are touch impression/imprints good for and how should they be made?

A
  • Evaluating excised tissue or superficial lesions
  • Imprints made BEFORE tissue placed in formalin to go to histopath
  • Use fresh cut surface (cut sample in half if necessary)
  • Blot until dry with paper towel
  • Roll sample against slide
  • Air dry and stain
9
Q

What type of pot should fluid be collected in to prevent clots?

A

EDTA

10
Q

What type of pot should bacteriology samples be placed in?

A

Sterile

11
Q

What are the 4 levels of analysis of cytology?

A
  1. Sample quality - enough cells, good condition, spreading, representative of lesion, normal cells as well as abnormal expected?
  2. Inflammation v. neoplasia
  3. Inflammatory = Septic v. Non-septic
  4. Neoplasia = Round cell v. Epithelial v. Spindle cell
  5. Neoplasia = Benign v. malignant
12
Q

How can inflammatory be distinguished from neoplasia changes?

A

Sample dominated by inflammatory cells (neutrophils/eosinophils/lymphocytes/macrophages)
or tissue cells (neoplasia)?
> If both are present, need experience as could be inflammation with 2* dysplasia or neoplasia with 2* inflammation
> biopsy required

13
Q

How can septic v non-septic inflammation be distinguished?

A

> Septic: bacteria/organisms WITHIN neutrophils, if extracellular may be contaminant. degenerate neutrophils [lysed due to O* burst]
Non-septic: No bacteria, no degenerate neutrophils.

14
Q

Outline degenerative changes in neutrophils

A
  • Nuclear change
  • Nucleus swells, loses lobulation and becomes paler (chromatin less condensed)
  • 2* to release of bacterial toxins
  • Degenerate neutrophils -> suspect septic cuases even if no bacteria seen
15
Q

What changes are seen in NON-degenerate neutrophils at the end of their life?

A

Pyknosis

16
Q

What may confused for bacteria?

A

Stain precipitate

17
Q

When are increased numbers of macrophages seen?

A

Granulomatous inflammation eg. Mycobacterium sp or FB

18
Q

What is ^ neutrophils and macrophages called? When is this seen?

A

Pyogranulomatous seen with fungal infections or FB

19
Q

How are round cell identified?

A
  • Individual cells not clustered
  • Small/medium round/oval cells eg. medium lymphocyte = 2x RBC
  • Round/oval nuclei
  • Well defined cell borders
  • Good cell yield
  • Seen better with cytology than histopath
20
Q

Give 6 types of round cell tumour

A
  • Lymphoma
  • Plasmacytoma
  • Histiocytoma
  • Mast cell tumour
  • Transmisable venereal tumour (TVT)
  • Melanoma
21
Q

How are epithelial cells identified?

A
  • Sheets/rafts/clusters
  • Large cell size
  • Cell-to-cell junctions but good cell border
  • oval/angular shape
  • Nuclei round andcentral
  • Cytoplasm often abundant
  • Good cell yield
  • eg. sebaceous, mammary, liver
22
Q

How are mesenchymal cells identified?

A
  • Individual cells OR clumps
  • Small medium sized
  • Spindle/fusiform/stellate
  • Indistinct cell border but not joined like epithlium
  • Elongated nucleus
  • Poor exfoliation
  • Matrix production -collagen/ostoid
23
Q

What are the benign and malignant tumours of epithelial cells?

A

Benign: Adenoma
Malignant: Carcinoma

24
Q

What are the benign and malignant tumours of mesenchymal cells?

A

Benign: Fibroma
Malignant: Fibrosarcoma

25
Q

What are the benign and malignant tumours of round cells?

A

Lots of different specific tumours with distinct prognosis and pathology
- Mast cell tumour only specific type

26
Q

How is malignancy assessed?

A

> uniformity vs. pleiomorphism [or dysplasia] - carcinoma, sarcoma (exception of Lymphoma where monotony indicates malignancy)
Cytoplasmic and nuclear [most reliable] features associated with malignant behaviour (3 criteria required to call tumour malignant):
- Anisocytosis (varied cell size)
- macrocytosis (large cell size)
- Cell overcrowding
- Anisokaryosis (varied nuclear size)
- Multinucleation +- odd numbers of nuclei
- Macrokaryosis (giant nuclei)
- High nuclear to cytoplasmic ratio (N:C) in large cells [ie. small amount of cytoplasm is bad]
- abnormal or ^ mitotic figures
- coarse chromatin
- nuclear moulding
- Within nucleus: MacronucleOLI, varying nucleolar shape and size

27
Q

Give some common problems seen with sample prep

A
  • Formalin fumes destroy blood smears and cytology
  • Refridgerating glass slides -> condensation ruins smear
  • Lack of fresh smears
  • Flies