PATHOLOGY - Neoplasia

Question 1

What are the five oncogenic retroviruses of veterinary significance?

Answer 1

Feline leukaemia virus (FeLV)
Bovine leukaemia virus (BLV)
Avian leukosis virus
Feline immunodeficiency virus (FIV)
Jaagsiekte sheep retrovirus (JSRV)

Question 2

What is the main oncogenic herpesvirus of veterinary significance?

Answer 2

Gallid alphaherpes virus 2

Question 3

Which neoplasias are caused by feline leukaemia virus (FeLV)?

Answer 3

Lymphoma
Leukaemia

Question 4

Which neoplasias are caused by bovine leukaemia virus (BLV)?

Answer 4

Lymphoma
Leukaemia

Question 5

Which neoplasias are caused by avian leukosis virus?

Answer 5

Lymphoma
Leukaemia

Question 6

Which neoplasia is caused by feline immunodeficiency virus (FIV)?

Answer 6

Lymphoma

Question 7

Which neoplasia is caused by Jaagsiekte sheep retrovirus (JSRV)?

Answer 7

Ovine pulmonary adenocarcinoma

Question 8

Which disease is caused by Gallid alphaherpesvirus 2?

Answer 8

Marek’s disease

Question 9

Which is the characteristic sign associated with Marek’s disease?

Answer 9

Marek’s disease is characterised by diffuse T-cell lymphomas

Question 10

What are the four differentials of round cell tumours?

Answer 10

Lymphoma
Mast cell tumours
Plasma cell tumours
Histiocytoma

Question 11

What is lymphoma?

Answer 11

Lymphoma is neoplasia of the lymphocytes (B-lymphocytes and T-lymphocytes) which can infiltrate and form tumours in the lymphatic system as well as other organ systems

Question 12

Which diagnostic technique can be used to differentiate between B-lymphocyte and T-lymphocyte lymphoma?

Answer 12

Immunohistochemistry

Question 13

How can immunohistochemistry be used to differentiate between B-lymphocyte and T-lymphocyte lymphoma?

Answer 13

Immunohistochemistry cen be used to differentiate between B-lymphocyte and T-lymphocyte lymphoma through detecting the expression of specific markers on neoplastic cells

Question 14

The detection of which marker by immunohistochemistry is indicative of B-lymphocyte lymphoma?

Answer 14

Marker CD79a

Question 15

The detection of which marker by immunohistochemistry is indicative of T-lymphocyte lymphoma?

Answer 15

Marker CD3

Question 16

What are the three anatomical classifications of lymphoma?

Answer 16

Multicentric lymphoma
Mediastinal lymphoma
Gastrointestinal lymphoma

Question 17

What is multicentric lymphoma?

Answer 17

Multicentric lymphoma refers to lymphoma that affects multiple lymph nodes (usually bilaterally) and lymphoid tissues throughout the body

Question 18

What is mediastinal lymphoma?

Answer 18

Mediastinal lymphoma refers to lymphoma that affects the mediastinal lymph nodes and lymphoid tissues (i.e. the thymus)

Question 19

What is gastrointestinal lymphoma?

Answer 19

Gastrointestinal lymphoma refers to lymphoma that affects the gastrointestinal organs and lymph nodes

Question 20

What are the two most significant bovine lymphomas?

Answer 20

Enzootic bovine lymphoma
Sporadic bovine lymphoma

Question 21

Which age group of cattle are most commonly affected by enzootic bovine lymphoma?

Answer 21

Adult cattle

Question 22

Which virus causes enzootic bovine lymphoma?

Answer 22

Bovine leukaemia virus (BLV)

Question 23

What are the two mechanisms of transmission of bovine leukaemia virus (BLV) between cattle?

Answer 23

Arthropod vectors
Reusing dirty needles

Question 24

Which age group of cattle are most commonly affected by sporadic bovine lymphoma?

Answer 24

Young cattle

Question 25

What are the two forms of sporadic bovine lymphoma?

Answer 25

Multicentric sporadic bovine lymphoma Thymic sporadic bovine lymphoma

Question 26

(T/F) Feline lymphoma is most commonly associated with neoplastic T-lymphocytes

Answer 26

TRUE.

Question 27

(T/F) Feline lymphoma is always caused by feline leukaemia virus (FeLV) infection

Answer 27

FALSE. Before the development of the feline leukaemia virus (FeLV) vaccination, the most common cause of feline lymphoma *was* FeLV, however, following the FeLV vaccination, most feline lymphoma cases are FeLV negative

Question 28

Describe the signalement for feline lymphoma caused by feline leukaemia virus (FeLV)

Answer 28

Young to middle aged cats presenting with mediastinal or multicentric lymphoma

Question 29

Describe the signalement for feline lymphoma that is **not** caused by feline leukaemia virus

Answer 29

Cats over ten years of age presenting with gastrointestinal lymphoma

Question 30

What is the most common subtype of gastrointestinal lymphoma seen in older cats?

Answer 30

Enteropathy-associated T-cell lymphoma

Question 31

Why is it so challenging to differentiate between enteropathy-associated T-cell lymphoma and inflammatory bowel disease in cats?

Answer 31

Enteropathy-associated T-cell lymphoma and inflammatory bowel disease are challenging to differentiate as both of these diseases are T-lymphocyte mediated diseases which infiltrate the gut and are commonly diagnosed in older cats with a similar clinical presentation

Question 32

Which diagnostic technique can be used to differentiate between enteropathy-associated T-cell lymphoma and inflammatory bowel disease in cats?

Answer 32

PCR for Antigen Receptor Rearrangement (PARR)

Question 33

How can PCR for Antigen Receptor Rearrangement (PARR) be used to differentiate between enteropathy-associated T-cell lymphoma and inflammatory bowel disease in cats?

Answer 33

PCR for Antigen Receptor Rearrangement (PARR) is a clonality assay that helps to distinguish neoplastic lymphocytes from inflammatory lymphocytes. Neoplastic lymphocytes exhibit clonal expansion and thus all of their antibodies are the same and detect the same antigens, however, inflammatory lymphocytes are polyclonal and each antibody differs and detects a different antigen

Question 34

What is the most common anatomical presentation of canine lymphoma?

Answer 34

Multicentric lymphoma

Question 35

(T/F) Canine lymphoma is most commonly associated with neoplastic T-lymphocytes

Answer 35

FALSE. Canine lymphoma is most commonly associated with neoplastic B-lymphocytes

Question 36

What are the two most significant canine lymphomas?

Answer 36

Canine diffuse B-cell lymphoma Canine T-zone lymphoma

Question 37

Describe the signalement for canine diffuse B-cell lymphoma

Answer 37

Adult, large breed dogs

Question 38

Describe the five stages of canine lymphoma

Answer 38

Stage 1: Single lymph node involvement Stage 2. Multiple lymph node involvement Stage 3: Generalised lymphadenopathy Stage 4: Liver and/or spleen involvement Stage 5: Bone, bone marrow, central nervous system (CNS) or other organ involvement

Question 39

What is the characteristic feature of mast cell tumours on histology?

Answer 39

Mast cell tumours are characterised by the presence of mast cells which are filled with histamine granules

Question 40

Which stain can be used to identify the histamine granules present within mast cell tumours?

Answer 40

Astra blue stain

Question 41

Describe the tumour grading system for mast cell tumours

Answer 41

Patnaik grade I: Well differentiated mast cell tumours with a good prognosis with surgical excision Patnaik grade II: Moderately-differentiated mast cell tumour Patnaik grade III: Malignant, invasive, metastatic mast cell tumour with a poor prognosis

Question 42

Describe the signalement for canine soft tissue sarcomas

Answer 42

Middle aged to old, medium to large breed dogs

Question 43

What are equine sarcoids?

Answer 43

Equine sarcoids are locally aggressive, non-metastatic fibroelastic skin tumours

Question 44

Which virus causes equine sarcoids?

Answer 44

Bovine papilloma virus (BPV)

Question 45

Describe the signalement for equine sarcoids

Answer 45

Three to six year old equids