Oncology: Feline Lymphoma, Leukaemia and Myeloma

Question 1

How does lymphoma in cats vary pre FeLV and Post FeLV

Answer 1

Pre
* Mediastinal/multicentric lymphoma in young/adult cats

Post
* GI lymphoma in geriatric cats
* >70% of feline lymphomas
* Most common intestinal tumour

Question 2

What increases the chance of developing lymphoma by 62x?

Answer 2

FeLV

Feline leukaemia virus

Question 3

1. How does FIV cause feline lymphoma?
2. Where is more commonly affected?

Answer 3

1. Immune suppression causes oncogenesis
2. GI tract- B cell lymphomas

Question 4

Other then FIV/FeLV what can increase incidence of feline lymphoma?

Answer 4

• Genetic predisposition
• Altered expression of oncogeneses
• Epigenetics
• Tobacco smoke
• Chronic inflammatory conditions

Question 5

What are the different ‘types’ of feliine lymphoma?

Answer 5

• Nodal (multicentric)
• Alimentary
• Mediastinal
• Extranodal

Also- nasal, laryngeal, CNS, ocular, cutaneous

Question 6

Where is nodal (multicentric) lymphoma more commonly found in cats?

Answer 6

‘True’ multicentric uncommon

Regional lymphadenopathy is more commmon
* Sub mandibular lymph nodes, medial iliac lymph nodes

Question 7

What are the clinical signs of nodal/multicentric lymphoma

What are the differentials?

Answer 7

CS
* Non-painful lymph node enlargment
* Anorexia
* Depression
* Non-specific malaise
* Pyrexia

Differentials
* Infections
* Immune mediated diseases
* Idiopathic forms
* Metastatic

Question 8

What are the clinical signs of mediastinal disease?

Answer 8

• Respiratory distress
• Regurgitation/dysphagia
• Weight loss
• Lethargy, excercise intolerance
• Cough

Clinical exam
* Palpable reduction in compressibility of cranial thorax
* Decreased lung sounds

Question 9

What are the differentials for mediastinal feline lymphoma?

Answer 9

Other cranial mediastinal lyphadenopathy
Other causes of pleural effusion
* Congenitive cardiac failure
* Pyothorax
* FIP
* Haemothorax

Question 10

What is the common presentation for a alimentary lymphoma?

Answer 10

• Older cats
• Insidious weight loss
• Anorexia
• Diarrhoea
• Malabsorption- PLE
• occasionally vomiting

Question 11

What are the differentials for mesenteric lymphoma?

Answer 11

Mesenteric lymphadenopathy
* FIP
* IBD
* Metastasis
* Pancreatitis
* Mycobacterial infection

Question 12

What type of cutaneous lymphoma core commonly affects cats?

How are they treated?

Answer 12

Non-epitheliotropic in cats

Not responsive to chemo
Retinoids- help

Question 13

How is lymphoma diagnosed?

Answer 13

• FNA and flow cytometry (thymoma vs lymphoma)
• Biopsy- avoid trucrut
• PARR- PCR for antigen receptor (negative does not exclude lymphoma)

Question 14

What are prognostic indicators of feline lymphoma?

Answer 14

Positive
* Achieving complete remission
* Small volume extranodal disease

Negative
* Failure to achieve CR
* FeLV status +ve

Question 15

How can lymphoma be treated?

Answer 15

• None
• Corticosteroids
• Multidrug regimens- COP, CHOP, COAP

Question 16

1. What is the MST for lymphoma without treatment?
2. MST for COP

Answer 16

1. 4 weeks
2. 1 year

COP = vincristine, cyclophosphamide, prednisolone

Question 17

What are the side effects of chemotherapy on cats?

Answer 17

Myelosuppressive agents
UTI
Hairloss- whiskers
GI signs

Question 18

How can an alimentary lymphoma be treated?

Answer 18

• Surgical excision of solitary mass lesion
• Follow up chemo?

Adequate supportive therapy

Question 19

How is leukaemia classified?

Answer 19

Classification by cell type and progression
* Acute vs chronic
* Lymphoid vs myeloid

Question 20

What are the two types of rapidly progressive, fatal diseases of leukaemia?

Answer 20

Acute lymphoid leukaemia
Acute myeloid leukaemia

High WBC counts
Concurrent pancytopenias
Poor prognosis

Question 21

How is acute leukaemia treated?

Answer 21

Supportive therapy
* Blood transfusion
* ABs
* Barrier nursing
* CSF

Multi-agent chemotherapy protocols
COP or CHOP

Question 22

What is the MST of chemotherapy treated acute leukaemia in dogs?

Answer 22

120 days

Question 23

What is chronic lymphoid/myeloid leukaemia?

Answer 23

Chronic lymphoid
* Proliferation of mature lymphocytes in bone marrow

Chronic myeloid leukaemia
* Proliferation of mature myeloid cells (neutrophils) in bone marrow

Question 24

How can chronic lymphoid leukaemia be rreated?

Answer 24

Rare

Treat with prednisolone/chlorambucil
Survival times 1-3 years

Question 25

How is leukaemia diagnosed?

Answer 25

• Haematology with manudal differential and smeal evaluatoin

Staging:
Thoracic radiographs
Abdominal US
Cytology of liver/spleen

Bone marrow biopsy

Question 26

1. What is myeloma AKA?
2. What is it?
3. How can it progress?

Answer 26

1. Multiple myeloma
2. Systemic neoplastic proliferation of plasma cells results in overproduction of antibody
3. Local disease, hyperproteinaemia, cytopenias, renal disease

Question 27

How is multiple myeloma diagnosed?

Answer 27

Haematology, biochem, urinalysis
* Non-specific
* Proteinuria
* Hypercalcaemia
* Hyperglobinemia

Diagnostic imaging
* Hepatosplenomegaly
* Osteolytic bone lesions

Cytology: liver, spleen and bone

Dogs need 2 of the 4
* Monoclonal gammopthy
* Osteolytic bone lesions- radiograph
* >5% neoplastic plasma cells
* Bence-jones proteinuria

Question 28

How is MM treated?

Answer 28

Supportive care
* Blood transfusions
* Plasmaphoeresis
* ABs
* Hypercalcaemia treatment

Systemic disease
* Prednisolone
* Chemo