Oncology: Feline Lymphoma, Leukaemia and Myeloma Flashcards
How does lymphoma in cats vary pre FeLV and Post FeLV
Pre
* Mediastinal/multicentric lymphoma in young/adult cats
Post
* GI lymphoma in geriatric cats
* >70% of feline lymphomas
* Most common intestinal tumour
What increases the chance of developing lymphoma by 62x?
FeLV
Feline leukaemia virus
- How does FIV cause feline lymphoma?
- Where is more commonly affected?
- Immune suppression causes oncogenesis
- GI tract- B cell lymphomas
Other then FIV/FeLV what can increase incidence of feline lymphoma?
- Genetic predisposition
- Altered expression of oncogeneses
- Epigenetics
- Tobacco smoke
- Chronic inflammatory conditions
What are the different ‘types’ of feliine lymphoma?
- Nodal (multicentric)
- Alimentary
- Mediastinal
- Extranodal
Also- nasal, laryngeal, CNS, ocular, cutaneous
Where is nodal (multicentric) lymphoma more commonly found in cats?
‘True’ multicentric uncommon
Regional lymphadenopathy is more commmon
* Sub mandibular lymph nodes, medial iliac lymph nodes
What are the clinical signs of nodal/multicentric lymphoma
What are the differentials?
CS
* Non-painful lymph node enlargment
* Anorexia
* Depression
* Non-specific malaise
* Pyrexia
Differentials
* Infections
* Immune mediated diseases
* Idiopathic forms
* Metastatic
What are the clinical signs of mediastinal disease?
- Respiratory distress
- Regurgitation/dysphagia
- Weight loss
- Lethargy, excercise intolerance
- Cough
Clinical exam
* Palpable reduction in compressibility of cranial thorax
* Decreased lung sounds
What are the differentials for mediastinal feline lymphoma?
Other cranial mediastinal lyphadenopathy
Other causes of pleural effusion
* Congenitive cardiac failure
* Pyothorax
* FIP
* Haemothorax
What is the common presentation for a alimentary lymphoma?
- Older cats
- Insidious weight loss
- Anorexia
- Diarrhoea
- Malabsorption- PLE
- occasionally vomiting
What are the differentials for mesenteric lymphoma?
Mesenteric lymphadenopathy
* FIP
* IBD
* Metastasis
* Pancreatitis
* Mycobacterial infection
What type of cutaneous lymphoma core commonly affects cats?
How are they treated?
Non-epitheliotropic in cats
Not responsive to chemo
Retinoids- help
How is lymphoma diagnosed?
- FNA and flow cytometry (thymoma vs lymphoma)
- Biopsy- avoid trucrut
- PARR- PCR for antigen receptor (negative does not exclude lymphoma)
What are prognostic indicators of feline lymphoma?
Positive
* Achieving complete remission
* Small volume extranodal disease
Negative
* Failure to achieve CR
* FeLV status +ve
How can lymphoma be treated?
- None
- Corticosteroids
- Multidrug regimens- COP, CHOP, COAP
- What is the MST for lymphoma without treatment?
- MST for COP
- 4 weeks
- 1 year
COP = vincristine, cyclophosphamide, prednisolone
What are the side effects of chemotherapy on cats?
Myelosuppressive agents
UTI
Hairloss- whiskers
GI signs
How can an alimentary lymphoma be treated?
- Surgical excision of solitary mass lesion
- Follow up chemo?
Adequate supportive therapy
How is leukaemia classified?
Classification by cell type and progression
* Acute vs chronic
* Lymphoid vs myeloid
What are the two types of rapidly progressive, fatal diseases of leukaemia?
Acute lymphoid leukaemia
Acute myeloid leukaemia
High WBC counts
Concurrent pancytopenias
Poor prognosis
How is acute leukaemia treated?
Supportive therapy
* Blood transfusion
* ABs
* Barrier nursing
* CSF
Multi-agent chemotherapy protocols
COP or CHOP
What is the MST of chemotherapy treated acute leukaemia in dogs?
120 days
What is chronic lymphoid/myeloid leukaemia?
Chronic lymphoid
* Proliferation of mature lymphocytes in bone marrow
Chronic myeloid leukaemia
* Proliferation of mature myeloid cells (neutrophils) in bone marrow
How can chronic lymphoid leukaemia be rreated?
Rare
Treat with prednisolone/chlorambucil
Survival times 1-3 years
How is leukaemia diagnosed?
- Haematology with manudal differential and smeal evaluatoin
Staging:
Thoracic radiographs
Abdominal US
Cytology of liver/spleen
Bone marrow biopsy
- What is myeloma AKA?
- What is it?
- How can it progress?
- Multiple myeloma
- Systemic neoplastic proliferation of plasma cells results in overproduction of antibody
- Local disease, hyperproteinaemia, cytopenias, renal disease
How is multiple myeloma diagnosed?
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
How is MM treated?
Supportive care
* Blood transfusions
* Plasmaphoeresis
* ABs
* Hypercalcaemia treatment
Systemic disease
* Prednisolone
* Chemo
