feline lymphoma

Pre vs post FeLV

Pre = mediastinal, multicentric, young/adult

Post = GI, geriatric

Viral causes + lymphoma types

FeLV - GI, extra nodal

FIV - GI

How does FeLV + FIV affect risk of lymphoma

80x inc risk

Causes

FeLV, FIV

Genetics

Altered oncogenes + tumour suppression genes

Epigenetics

Tobacco

Chronic infl

Types of lymphoma in cats

Nodal-Multicentric

Alimentary

Mediastinal

Extra nodal - nasal, retrobulbar, laryngeal, renal, CNS, ocular, cutaneous

Nodal-multicentric - gross

Symmetrical generalised lymphadenopathy (rare) / regional lymphadenopathy (common)

Nodal-multicentric - Age

Middle aged

Nodal-multicentric - CS

Non painful LN enlargement

Anorexia

Dep

Malaise

Pyrexia

PUPD

Mediastinal - common age + breed

Young, Siamese

Mediastinal - CS

Resp dist, regurg, dysphagia, WL, leth, ex int, cough

Mediastinal - CE findings

Palp reduction in compressibility of cr thorax

Dec lung sounds

Cr oedema

Mediastinal - Ddx as causes cr mediastinal lymphadenopathy + pleural effusion

Thymoma

CHF, pyothorax, FIP, haemothorax

Alimentary - age

Old

Alimentary - CS

WL, anorexia, D, PLE, V (gastric involvement)

Alimentary - Ddx as causes mesenteric lmyphadenpathy + GI signs

FIP, peritonitis, IBD, metastatic Neo, pancreatitis, mycobacterium

Extra nodal - CNS CS

Depends on site

Extra nodal - nasal/retrobulbar CS

Nasal discharge, epistaxis, obstruction, exophthalmos

Extra nodal - renal CS

Malaise, anorexia, bilateral renomegaly, azotaemia

Usually CNS too

Cutaneous - type

Non epitheliotrophic

Cutaneous - Common drug needed (poor chemo response)

Retinoids

Dx - FNA ideal for which types (not as good as dogs)

Cr mediastinal, extranodal

Dx - Why is FNA not ideal

Low grade small cell/ mixed lymphomas in cats → hard to differentiate from reactive hyperplasia

Dx - Biopsy options

Excisional, wedge

Avoid trucut

PCR ag receptor rearrangements + and -

+ shows clonality, high specificity

- clonality in infl too, negative doesn’t exclude

How is staging + grading different in cats

No system in use

Immunophenotype not prognostic

Positive prognostic indicators

Complete response

Small vol extranodal

Negative prognostic indicators

Fail to achieve complete response

FeLV +

Tx options

None

Corticosteroids

Multi drug regimes - COP, CHOP, COAP

Non continuous regimes

Tx options - what happens if you do nothing

4w survival

Tx options - what happens if you do COP

49% survive 1yr

COP vs CHOP in dogs + cats

High dose COP = cats

CHOP = dogs

High dose COP drugs

Vincristine

Cyclophosphamide

Prednisolone

How to monitor myelosupp side effects

Check haem + urine before

Common side effects

Myelosupp

Hair + whisker loss

GI

Alimentary tx

Sx excision + biopsy

Supportive - appetite stimulants, tube, vit b12

Alimentary low grade Epitheliotropic tx

Chlorambucil, prednisolone

Rescue therapy in relapse

Doxorubicin/ Lomustine

Radiation