Histopathology 3: Cytopathology

Question 1

what is cytopathology split into?

Answer 1

Gynaecological Cytopathology
NHS CSP smears
Diagnostic (symptomatic) smears and endometrial sampling

Non-Gynaecological Cytopathology
Exfoliative (serous effusion, joint, respiratory, GI, CSF)
Aspiration (lymph node, salivary gland, skin and soft tissue masses, cysts, breast, thyroid…)

Question 2

list 5 serous membranes

Answer 2

Pericardium, Pleura, Abdominal Cavity, Tunica Vaginalis of testis

Question 3

what is a serous membrane?

Answer 3

Connective tissue lined by mesothelial cells

Question 4

what are the features of the a transudate?

Answer 4

Plasma ultrafiltrate
‘Mechanical’ –Hydrostatic Oncotic
Clear, pale yellow, low protein (<3g/dL), doesn’t clot
Single bland degenerate mesothelial cells and a few macrophages and lymphocytes

usually benign

Question 5

causes of transudate?

Answer 5

Cardiac, Cirrhosis, Nephrotic, Hypoproteinemia

Question 6

what are the features of the a exudate?

Answer 6

Unfiltered plasma
Changes in vascular permeability
Cloudy, yellow or bloody, high protein (>3g/dL), clots
Many cells with proteinaceous background
Inflammation (infection, infarction, autoimmune)
May be malignant

Question 7

if it is pale yellow and watery, what does it point towards?

Answer 7

Transudate from CCF cirrhosis protein

Question 8

if it is turbid and yellow/white?

Answer 8

Infection, malignancy, pancreatitis

Question 9

if it is milky white/greenish?

Answer 9

Chylous effusion from thoracic duct obstruction (trauma, lymphoma)

Question 10

if it is milky with a silky sheen ?

Answer 10

Pseudochylous effusion caused by cholesterol from TB, rheumatoid disease or an old effusion

Question 11

if it is brown?

Answer 11

Haemorrhage (trauma pancreatitis malignancy) or melanin

Question 12

if it is green?

Answer 12

Bile from biliary tract disease or ruptured bowel

Question 13

if it is gelatinous

Answer 13

Hyaluronic acid from mesothelioma or mucin in pseudomyxoma

Question 14

features of mesothelial cells

Answer 14

mesodermal epithelium
Microvilli
Single and grouped
Clusters, balls, papillae, cell-in-cell, indian files
Vary in size
Lacy edges
Windows
Molding

Question 15

features of macrophages?

Answer 15

Usually present
Can be difficult to separate from mesothelial cells (esp. degenerate)
Usually single or in loose aggregates
Foamy pale cytoplasm
Eccentric bean shaped nucleus
Lack molding, windows

Question 16

features of lymphocytes?

Answer 16

Usually a few present
More frequent in longstanding effusions
May be a range of maturation

Question 17

features of neutorphils

Answer 17

Often find a few
If non-infectious may be well preserved
If infectious then often degenerate
If masses then usually benign

Question 18

what is an LE cell?

Answer 18

A neutrophil or macrophage with an engulfed/phagocytised nucleus seen in SLE

Question 19

what are the features of malignancy?

Answer 19

Enlarged
Increased N:C ratio
Irregular membranes
Inclusions
Coarse Irregular Chromatin

Question 20

what features are seen in breast Ca on cytology?

Answer 20

Proliferation spheres
Diffuse cell pattern
Intracytoplasmic lumina, may dilate to look like signet ring
Microvilli and mucin
Indian files

Question 21

what features are seen in lung Ca on cytology?

Answer 21

Dense cytoplasm
Papillary groups
May be highly vacuolated

Question 22

what features are seen in stomach Ca on cytology?

Answer 22

Usually dispersed single cells but may form papillae or acini
Signet ring or columnar cells
Signet ring cells have many tiny vacuoles

Question 23

what features are seen in CRC on cytology?

Answer 23

Papillary and acinar aggregates
Tall columnar cells
Nuclear palisading with nuclear membrane irregularities

Question 24

what are the features of mesothelioma compared to carcinoma?

Answer 24

Diffuse nodular pleural thickening (versus discrete)
Often unilateral (versus bilateral)
Thickening of fissures (versus intraparenchymal nodules)

Question 25

what are specific markers of mesothelioma?

Answer 25

Calretinin (cplasm+nuclei)

CK5/6 (cplasm)

Question 26

what are the pros of FNA?

Answer 26

Minimal pain and post procedural discomfort
Anaesthesia requirement minimal
Outpatient procedure
Saves time and hospital admission
Rapid result
Equipment simple and cheap
Excellent cell preservation due to rapid fixation
Fresh tissue available eg for microbiology or genetic analysis

Question 27

why is FNA good for management ?

Answer 27

Easily repeated allowing sampling of several areas with minimal trauma
Minimal disturbance of tissue planes
Confirms malignancy leaving lesion intact
May be therapeutic for cysts and abscesses
Quick feedback enables planning of other investigations
Monitor therapy by repeated sampling

Question 28

how do you fix cytology?

Answer 28

air dry or alcohol fix NEVER IN FORMALIN.

Question 29

compare air dried vs alcohol fixation

Answer 29

Fixed: 
nuclear detail
	transparent
	keratinisation
	squamous differentiation
	hyperchromasia
	necrosis
	bit like histology

Air dried:
cytoplasmic features
background substance
mucin, granules
glandular and lymphoid
metachromasia
microbial agents
bit like marrow

Question 30

where can cells originate from for a FNA of LN?

Answer 30

Cells from germinal centres

Cells from interfollicular areas and sinuses

Question 31

what would cause granulomatous lymphadenitis ?

Answer 31

TB
Cat scratch, leprosy, paracoccidioidomycosis, histoplasmosis, leishmaniasis, LGV, brucellosis
Foreign body (talc, silica)
Lymphoma
Carcinoma
Sarcoid

Question 32

define granuloma

Answer 32

a collection of activated epithelioid histiocytes