Principles of Cytology

Question 1

How to characterise a cytology sample

Answer 1

Is the sample adequate
Inflammatory vs. neoplastic vs. cystic

Question 2

How to characterise inflammation in cytology sample

Answer 2

suppurative vs. granulomatous vs. eosinophilic etc.
Look for evidence of sepsis

Question 3

How to characterise neoplasia in cytology sample

Answer 3

Epithelial vs. round cell vs. mesenchymal
benign vs. malignant

Question 4

process for cytological examination

Answer 4

Low power review- find good places to look at
Assess Quality- any/how many cells, well/poorly preserved
Background- Haemorrhage, granules, protein, matrix, debris, disrupted cells
Predominant cells- neutrophils?/other cells
Look at cells (x40 or oil)

Question 5

What to assess about cells in cytology

Answer 5

Individual vs. organised
single or mixed population
cell size, shape, variation
Nuclear size, shape, variation, abnormal mitoses

Question 6

Approach to unknown mass

Answer 6

Is the sample sufficient for diagnosis
Inflammatory - what type, septic
Is there cystic content- what type
mainly tissue cells -> neoplasia
- what type, benign or malignant

Question 7

Approach to cytology of known tissues

Answer 7

E.g., lymphnode, prostate, spleen, liver
Is the sample sufficient for diagnosis
Think about the normal cell population in that tissue; does what you have on the slide match that. E.g., should it be epithelial, round or mesenchymal or a mixture, what functional cells should be present
Think about possible pathologies (e.g., what 4 things cause lymph nodes to enlarge, what 4 things cause prostatic enlargement); which does the cytology best fit with?
Is there evidence of inflammation
Which of my narrowed list of possibilities fits best?

Question 8

Approach to cavity effusion cytology

Answer 8

Protein content
cell count
classification - exudate/ transudate
Cell types- neutrophils, degenerate/ on-degenerate, bacteria
Lining cells
Epithelial cell (carcinomatosis), lymphoid cells (chyle)

Question 9

Reactive mesothelial cells

Answer 9

Lining cells that can be mistaken for neoplastic cells

Question 10

Cytological criteria for malignancy

Answer 10

Cells ‘alien’ to position which they are found
Pleomorphism (variation) within a cell type
Variable cell size- anisocytosis
Lymphoid tissue malignancy has a monomorphic cell population where there should be variation
High and/or variable nuclear to cytoplasmic ratio

Question 11

Nuclear criteria of malignancy (4)

Answer 11

Variation in shape/size (anisocytosis)
- ratio of smallest diameter to largest >1.5
Multiple, fragmented, or moulded nuclei
Clumped chromatin- some white patches and some darker patches in nucleus
Multiple/irregular nucleoli
abnormal mitotic figures

Question 12

Cytoplasmic criteria of malignancy (4)

Answer 12

Basophilia/hyperchromatic (darker blue colour)
Vacuolation
Granularity
Phagocytosis of other cells

Question 13

What is reactive hyperplasia

Answer 13

Enlarged due to increased activity
In case of lymph nodes- in response to illness, increased production of lymphocytes

Question 14

what is lymphadenitis

Answer 14

Inflammation of lymph nodes
Would see neutrophils, macrophages or eosinophils coming into lymph node