Cytology

Question 1

Utility of cytology

Answer 1

Non-invasive
No anesthesia
Fast results
Cost effective
Fast treatment

Question 2

Limitations of cytology

Answer 2

Small sample area: actual cause of lesion may be missed
Nondiagnostic samples occur: poorly exfoliating lesions,
acellular samples
ruptured cells
blood contamination
improper slide prep/staining

Question 3

What kind of sampling do you do on a solid mass?

Answer 3

Aspiration
Fenestration
Impression smear

Question 4

What kind of sampling do you do on a fluid filled mass?

Answer 4

Aspiration

Question 5

Sample collection protocols

Answer 5

Multiple areas should be sampled
Aspirate edges of large lesions to avoid necrotic centers
DO NOT heat fix or expose to formalin

Question 6

Common cytological artifacts

Answer 6

Lube/alcohol
Glove powder
Pollen
Finger prints/anucleated squamous epithelial cells

Question 7

Aspiration of epidermal inclusion cyst will yield?

Answer 7

Cheesy material
Kertinized epithelium
Cholesterol crystals
+/- inflammation

Question 8

Aspiration of an aprocrine cyst will yield what?

Answer 8

Clear fluid
low cellularity

Question 9

Aspiration of a sebaceous cyst will yield what?

Answer 9

Brown/oily fluid
low cellularity
Basophilic proteinaceous background

Question 10

Aspiration of hematoma and seromas

Answer 10

Fluid filled
May need to be concentrated by centrifugation
Hematomas: hemodilute, low numbers MQ, no platelet
Seromas: low #s erythrocytes, occ. reactive MQ, no platelets, +/_ neutrophils

Question 11

Causes of lymphocytic inflammation

Answer 11

Antigenic stimulation: insect bites, vaccines, virus
Type IV hypersensitivity

Question 12

Causes of neutrophilic inflammation

Answer 12

Chronic inflammatory processes
Will be supperative, purulent
Degenerate: karyolytic, bacterial or fungal infection
Non-degenerate: sterile inflammatory process (immune mediated, caustic injury, trauma)

Question 13

Causes of eosinophilic inflammation

Answer 13

Parasitic infestations
Allergy/Type I hypersens.
Immune mediated diseases
Paraneoplastic onditions (mast cell tumors, carcinomas)

Question 14

Causes of histiocytic inflammation

Answer 14

Reactive MQs predominate/multinucleated giant cells
Foreign body reaction (hair shaft/stick)
Fungal infection
Atypical bacterial infection
Chronic irritation

Question 15

What kind of inflammation do you expect to see with pyogranulomatous inflammation?

Answer 15

Neutrophilic and histiocytic inflammation

Question 16

Causes of mixed inflammation?

Answer 16

Lick granulomas
Vax reaction
Persistent infections
Foreign body reactions

Question 17

What type of cells are spindle-shaped?

Answer 17

Mesenchymal cells

Question 18

What does anisocytosis mean?

Answer 18

Different sized cells (characteristic of malignancy)

Question 19

What does anisokaryosis mean?

Answer 19

Different sized nuclei
(characteristic of malignancy)

Question 20

Epithelial cell appearance

Answer 20

Large cells
High cellularity
Sheets with cell junctions
Distinct cytoplasmic borders
round to polygonal nuclei

Question 21

Common benign epithelial neoplasms

Answer 21

Papilloma
Adenoma
Basal cell tumors

Question 22

Follicular tumors

Answer 22

Basal epithelial cells
Common on head and neck
Benign: cats, horses, dogs
Malignant: common in cats, rare in dogs

Question 23

Common malignant epithelial neoplasms

Answer 23

Adenocarcinoma
Squamous cell carcinoma
Transitional cell carcinoma
Anal sac adenocarcinoma (hypercalcemia)

Question 24

Benign mesenchymal tumors

Answer 24

Lipomas
Fibromas
Neurofibromas
Myxomas
Nerve-sheath tumors
Perivascular wall tumors
Sarcoids (horses)

Question 25

What is the criteria for a mesenchymal tumor to be malignant?

Answer 25

Must have at least 5 characteristics of malignancy but rarely metastasize

Question 26

Round cell tumors

Answer 26

Mast cell tumor Plasma cell tumor Histiocytoma Transmissible Venereal tumor Lymphoma Melanoma

Question 27

What is transudation?

Answer 27

Low oncotic pressure due to hypoalbuminemia High hydrostatic pressure Low cellularity and low protein

Question 28

What is exudation?

Answer 28

Inflammatory-increased vascular permeability due to inflammation Cellular and proteinaceous: neutrophils, MQs, fibrin, globulins

Question 29

Transudate pathogenesis

Answer 29

Severe right atrial and ventricular dilation Tricuspid valve dysplasia Severe tricuspid valve insufficiency

Question 30

Uroabdomen pathogenesis

Answer 30

Low protein, low cell count at first but will increase if chronic Creatinine higher than serum levels Biochem: azotemia, hyperkalemia

Question 31

Chylous effusion pathogenesis

Answer 31

Rupture of thoracic duct triglyceride rich fluid from lacteals Secondary to trauma, tumor, idiopathic

Question 32

Hemorrhagic effusion pathogenesis

Answer 32

Rupture of spleen or liver, heart based tumor: hematoma or hemangiosarcoma PCV close to that of peripheral blood Hemosiderin containing MQs

Question 33

Cytology of normal/hyperplastic lymph nodes

Answer 33

75-95% small, well-differentiated lymphocytes

Question 34

Cytology of reactive lymphoid tissue

Answer 34

mostly small, well-differentiated lymphocytes Increased numbers of intermediate and large lymphocytes Some more plasma cells, some Mott cells, some neutrophils and macrophages