CS: Lymphadenomegaly Flashcards
How can a monoclonal and polyclonal gammopathy be distinguished?
Gel protein electrophoresis
- if base of peak is == or narrower than the albumen peak then it is MONOclonal
What is the stress leucogram?
- neutrophilia, lymphopenia
What urine changes may be seen alongside a mono/polyclonal gammopathy?
proteinuria d/t compensatory albumen response - as gamma globulins maintain oncotic pressure of the blood albumen can be lost through the kidneys -> albumenuria
How can Leishmania be detected?
leish test - ELISA
Positive titre is a number greater than the cut off, ie. can be diluted more and still give a positive result
How can Lymphoma be differentiated from ALL?
On PE difficult to differentiate – may be based on degree of lymphadenopathy, clinical signs, degree of cytopenias
> ultimately the flow cytometry markers, CD34 stem cell marker to distinguish (positive in ALL, usually negative in stage V lymphoma)
What factors affect the prognosis in dogs with lymphoma and leukaemia?
- Lymphoma: Stage (stage I and II may have better prognosis, in some studies stage V has a worse prognosis, but not in all). Substage b has worse prognosis than a. Immunophenotype (B has better prognosis than T for high grade lymphomas), how you treat them (e.g. combination chemotherapy vs prednisolone alone).
- Hypercalcaemia is a poor prognostic indicator (but usually because commonly associated with T-cell)
- Leukaemia: Acute vs chronic, lymphoid vs myeloid. (See lecture notes – prognosis better for chronic leukaemia vs acute; and lymphoid has better prognosis than myeloid.
Design a management plan for dog with stage V lymphoma of the tonsils and submanduibular LNs, having difficulty swallowing and breathing. What factors need to be considered?
- Neutropenia– ABs for risk of infection – home management vs hospitalisation of this case?: If eating ok and reasonably bright and afebrile then have at home where less likely to pick up an infection, on oral antibiotics e.g. TMS. In cases that are sick / febrile / GI signs present, then give IV ABs, broad spectrum like potentiated amoxicillin plus enrofloxacin and IVFT, barrier nurse in hospital
- Thrombocytopenia – Gentle handling
- Choice of drugs –Most chemotherapy drugs are myelosuppressive – the dog’s neutropenic and thrombocytopenic status causes a problem!
- Ideally start with L-Asparaginase (rapid action not myelosuppressive) and prednisolone. However, L-asparaginase is expensive! If the client cannot afford it you may have to go ahead with vincristine (one of the less myelosuppressive agents and might help platelets bud off from megakaryocytes) and prednisolone with antibiotic cover on board
- Recheck CBC after a few days
- Consider introducing other drugs e.g. If used L-asparaginase initially you could introduce vincristine at this point.
- Hope to get onto COP or CHOP protocol.
Take home messages when thinking about lymphoma and leukaemia
> Lymphoma is the most common neoplastic cause of marked generalised lymphadenopathy in dogs.
- It can be rapidly progressive and in this case the dog’s tonsil involvement causing pharyngeal obstruction needed prompt attention.
- Important to perform blood tests prior to embarking on chemotherapy for lymphoma – to know what’s happening at baseline prior to any drug treatment and to recognise how blood results can affect the treatment plan.
Prognosis is better for lymphoma than for ALL – For lymphoma, MST of 12-13 months with CHOP type protocol (might be a bit less if extensive bone marrow involvement at outset) For ALL only about 1/3 of dogs respond to treatment and of those that respond MST is around 4 mo.
What type of PE should always be carried out for PUPD dogs?
Rectal - check for anal sac carcinoma -> hyperCa
- some rectal masses can be quite small
How should sublumbar LN FNA be carried out?
Ultrasound guided - many important vessels and nerves in this area
If rectal mass found, what should also be carreid out?
Imaging of the thorax to check for mets - staging helps decide tx plan
What margins should be taken for anal sac carcinomas?
Aim for clean margins but rarely possible without risking feacal incontinence
Tx anal sac carcinomas?
Surgery to remove the mass, radiation to clear the remaining margins and tx local LNs in case of metastasis
- chemo for incompletely resected masses: Examples of drugs used: toceranib, melphalan, metronomic chemotherapy, mitoxantrone, or carboplatin
- bisphosphonates if hyper calcaemia remains after surgery
If local lymphadenomegaly is found, what must be considered?
Area that drains to the specific LN
What would you see with lymphoma on FNA, ultrasound, bloods etc.?
- 50% immature cells
- large immarture lymphocytes
- cytopenia on bloods (if BM invovlement) abnormal circulating cells
- CD34 negative
