SA Oncology Flashcards
How do you usually assess staging of oral tumours?
Under GA
FNA or biopsy
Assess local lymph nodes in all cases (can contain tumour even if not enlarged)
Advanced imaging eg CT
How do you carry out distant staging of oral tumours?
Depends on tumour type
Thoracic imaging adequate for some
Abdominal imaging also for melanoma (can migrate to abdomen as well as thorax)
When doing surgical removal of an oral tumour, what margins should you include?
At least 2cm
What would be your first choice for management of an oral tumour?
Surgery (over radiotherapy) where excision is possible
Give some complications of performing oral tumour surgery in cats and dogs
Bleeding, recurrence, infection, altered cosmetic appearance, difficulty prehending food, salivation, mandibular drift after hemi-mandibulectomy
Small number of cases may never eat normally again
Give some clinical signs of oral tumours in small animals
Mass/facial swelling Oral bleeding Dysphagia/pain Loose teeth/ proliferative or ulcerative lesions noticed at dentals Halitosis Epistaxis (if invading nasal cavity) Cervical lymphadenopathy
How much mammary tissue should you remove with low-risk lesions?
Single mastectomy (single gland)
What excision margins should you use for mobile and fixed mammary tumours?
Mobile: whole gland removal is enough
Fixed: need 2cm margins and removal of affected abdominal fascia/wall
Is it advisable to neuter dogs at the time of mastectomy when removing mammary tumours?
Might reduce the risk of further tumour development, and improve survival of dogs with complex carcinoma
What is Ki-67?
Marker of dividing cells
A FNA taken of a canine inflammatory carcinoma would show what?
Inflammatory cells and tumour cells
What is the prognosis of canine inflammatory carcinomas?
Explain
Poor prognosis Excision not typically feasible Recurrence very common Treatment is palliative Medical therapy might prolong survival by a few months
Which systemic therapy drugs could you use when treating canine mammary tumours?
5-FU and cyclophosphamide shown to be beneficial in one small study
Pre-operative desmopressin prolongs survival in higher grade tumours
What % of feline mammary tumours are malignant?
85-95%
How does mammary tumour size affect mean survival time in cats?
> 2 cm: MST= 6 months
< 2 cm: MST= > 3 years
Which lymph nodes should you asses when investigating feline mammary tumours?
Inguinal and axillary bilaterally
Regarding feline mammary tumours, is it better to perform chain mastectomy or regional mastectomy?
Chain in cats, regional in dogs
What is the optimum treatment plan for feline mammary tumours?
Surgery and chemotherapy (doxyrubicin/cyclophospamide)
Why should you radiograph the abdomen as well as the thorax when staging melanoma?
Melanomas may migrate to the abdomen as well as thorax
What treatment would you recommend for a fibrosarcoma or squamous cell carcinoma?
Surgery followed by adjuvant radiotherapy generally gives better results than surgery alone
Why is radiotherapy alone a reasonable treatment option for oral melanoma?
Surgery is associated with high rates of local recurrence
How is diagnosis of melanoma achieved?
Melanin-containing mesenchymal cells on histology
Some tumours don’t contain melanin and IHC (immunohistochemistry) is required for diagnosis
How aggressive are oral melanomas?
Locally invasive
High metastatic rates (up to 80%)
Describe some anti-metastatic treatments for melanoma
Chemotherapy can cause shrinkage of tumours but does not appear to extend survival
Plasmid vaccine immunotherapy
How aggressive are oral squamous cell carcinomas?
Low metastatic rate
Low recurral rates (eg 10% for mandible)
What is the third most common canine tumour?
Fibrosarcoma
What medical therapy can you use to treat oral squamous cell carcinoma?
Piroxicam (NSAID) +/- carboplatin (chemo drug)
Give some clinical signs of a tonsilar squamous cell carcinoma
Dysphagia, coughing
Enlarged cervical lymph nodes -> abscessation
Enlargement of one or both tonsils
What is the metastatic rate of tonsilar squamous cell carcinoma?
> 70%
How do you treat tonsilar squamous cell carcinoma?
Local control of tonsilar enlargement: surgery or radiotherapy
Surgery or radiotherapy for lymph node metastasis
Carboplatin or mitoxantrone chemotherapy might be beneficial
Fibrosarcomas mostly affect which types of dogs?
Of which age?
Large breed dogs eg labrador Middle aged (7.5 years on average)
How aggressive are fibrosarcomas?
Invasive
Low/moderate metastatic risk (lung and occasionally lymph nodes)
How would you treat a fibrosarcoma?
Surgery, but high recurrence rate (40-60%) (MST=12 months)
Multimodal therapy ofen best (surgery plus radiotherapy) (MST=18-26 months)
Can do radiotherapy alone (MST=7 months)
Smaller tumours= better outcomes
Describe a low histological grade, high biological grade sarcoma of the mouth
Aggressive, rapidly-progressing oral tumour with benign histological appearance even after large biopsy
Very locally invasive
How would you treat a low histological grade, high biological grade sarcoma of the mouth?
Surgery and radiotherapy as very locally invasive
What are epulides?
Benign lesions arisimg from the gingiva
What are the 2 types of epulides?
Acanthomatous: aggressive local behaviour, bone invasion
Peripheral ondontogenic fibroma: slow growing firm masses, usually not invasive
How do you treat an osteosarcoma?
Surgery (radiotherapy does not extend survival)
Complete excision vital
Does a mandibular or maxillary osteosarcoma have a better prognosis?
Mandibular (14-18 months vs 5-10 months)
What is the local recurrence rate of an oral osteosarcoma?
> 80%
What is the most common feline oral tumour?
Squamous cell carcinoma
What 3 factors increase the risk of a cat developing oral squamous cell carcinoma?
Use of flea collars
Exposure to smoking
Canned foood inc tuna
What is the most common site of a feline oral squamous cell carcinoma?
Base of tongue
How aggressive is a feline oral squamous cell carcinoma?
Invades bone
Low metastatic risk (higher risk in caudal lesions)
Recurrence after surgery is common
Which tumour type can be described as having a ‘popcorn’ appearance on radiographs?
Multilobular osteocondrosarcoma
How does viral papillomatosis appear?
Do you treat it?
Wart-like lesions affecting oral soft tissues
Usually resolve in 4-8 weeks
Which dog breeds are more prone to oral eosinophilic granulomas?
Where are they found?
Husky, cavalier king charles spaniel
Found on the ventral and lateral aspects of the tongue
How do you treat an eosinophilic granuloma?
Surgery and corticosteroids
Where are oral eosinophilic granulomas found in cats?
How do you treat them?
Upper lip, mear midline
Steroids/hyperallergenic diets, radiotherapy, surgery
From when is there no risk reduction in neutering of mammary tumours?
No risk reduction after second season
How does obesity lead to increased risk of mammary tumours?
Obesity -> reduced sex hormone-binding globulin -> increased oestrogen levels
What is the mean age of dogs with benign mammary tumours?
What about malignant mammary tumours?
Benign: 7-9 years
Malignant: 9-11 years
What is the mean age of cats who develop mammary tumours?
10-12 years
Which dog breeds are more prone to mammary tumours?
Poodles, chihuahuas, dachshund, maltese, cocker spaniel, yorkshire terrier
Which cat breeds are more prone to mammary tumours?
Siamese
How can you diagnose mammary tumours?
Can use FNA to exclude other ddx
Excisional biopsy
How can you stage a mammary tumour?
Local staging: assessment of local lymph nodes
Cranial 2 glands drain to axillary lymph node
Caudal 2 glands drain to inguinal lymph node
Middle gland drains either way
Distant staging: thoracic radiographs, abdominal US, consider bone pain as mammary tumours can metastasize to bone
Where do lymphomas arise?
Arise from lymphoreticular cells (T or B cells)
Normally arise from lymphoid tissue but can arise from virtually any tissue
Give 2 dog breeds that are pre-disposed to lymphoma
Boxers
Bull mastiffs
Give some factors that may predispose a dog to lymphoma
Genetic and molecular factors
Infectious diseases
Toxins (eg pesticides)
Immunological factors (animals on immunosuppressive tx are more likely to develop lymphoma)
What age of dog is more likely to develop lymphoma?
Middle aged to older
Although can affect any age
What are the 5 presentations of lymphoma?
Multicentric (can appear in any location, mainly lymph nodes) Craniomediastinal Alimentary Cutaneous Extra-nodal (CNS, renal, heart, bladder)
What clinical signs would you see in a dog with multicentric lymphoma?
Generalised peripheral lymphadenopathy +/- other clinical signs
Some dogs clinically well
Rapid deterioration
Non-specific signs (weight loss, inappetence/anorexia, lethargy, pyrexia)
Specific signs (diarrhoea, cough, vomiting, ocular signs)
Regional oedema if lymph drainage is impaired
What clinical signs would you see in a dog with cranial mediastinal lymphoma?
Tachypnoea, dyspnoea
Signs of hypercalcaemia (muscle tremors, PUPD, vomiting/diarrhoea, anorexia, weight loss)
Occasionally vena cava syndrome (obstruction of vena cava -> pleural effusion, dyspnoea, ascites, subcutaneous oedema)
Altered PMI of heart on auscultation (heart is caudal to where we expect to find it)
Give some clinical signs of alimentary lymphoma in dogs
Weight loss, anorexia, pan-hypoproteinaemia (hypoalbuminaemia), evidence of malabsorption
Abdominal/diffuse masses
Occasionally multicentric lymphadenopathy
Tends to be aggressive in dogs
Wha are the 2 forms of cutaneous lymphoma?
Epitheliotrophic: T cells, solitary or generalised
Non-epitheliotrophic: more frequently B cells, more likely to have lesions elsewhere
Different appearances. Progression to raised, erythematous plaques/nodules. Variable pruritus.
Is cutaneous lymphoma responsive to chemotherapy?
Poorly responsive
Describe extranodal CNS lesions in dogs
Mass lesion or diffuse
Variable neurological deficits
Commonly ocular involvement
Generally T cell
What is meant by a paraneoplastic syndrome?
A syndrome (set of signs and symptoms) that is a consequence of the tumour but is not due to the presence of tumour cells in that location
What signs of neoplastic syndrome may you see with lymphoma?
Hypercalcaemia Immune-mediated diseases (eg pemphigus, IMHA) (as Neoplastic B cells can release monoclonal immunoglobulins) Monoclonal gammopathies Neuropathies Cachexia
How do you diagnose canine lymphoma?
Cytology or histopathology Ancillary tests: -PARR (false positives and negatives) -Flow cytometry (false positives and negatives) -Immunohistochemistry
Elements of which virus have been found in tumour tissue in cats with lymphoma?
FeLV
These cats, however, are FeLV negative
Cats have a 80x increased risk of lymphoma if they have which two viruses?
FeLV and FIV
What is meant by ‘extranodal’ lymphoma?
Lymphoma originating in non-lymphoid tissue
Cats of what age are affected by multicentric lymphoma?
Middle aged
Do cats with multicentric lymphoma tend to have regional or generalised lymphadenopathy?
Regional
Give the clinical signs of multicentric lymphoma in cats?
Non-painful regional lymph node enlargement Anorexia Depression Non-specific malaise Pyrexia (PUPD)
What condition do dogs get secondary to lymphoma which cats do not?
Hypercalcaemia
Which age of cats is more likely to get cranial mediastinal lymphoma?
Is a certain breed more prone?
Younger (2-3 years old)
Siamese
Give the clinical signs of cranial mediastinal lymphoma in cats
Respiratory distress Regurgitation/distress (mass is compressing oesophagus) Weight loss Lethargy, exercise intolerance Cough (rare) Palpable reduction in compressibility of cranial thorax Deceased lung sounds May have pleural effusion
What is the most common type of lymphoma in cats?
What age of cats are affected?
Alimentary Older cats (>10 yrs old)
Give the clinical signs of alimentary lymphoma in cats?
Insidious weight loss Anorexia Diarrhoea Malabsorption/PLE Occasionally vomiting (secondary gastritis)
Give the 3 main categories of extranodal lymphoma in cats and their clinical signs
CNS (signs depend on site)
Nasal/retrobulbar (nasal discharge, epistaxis, obstruction, exopthalmus)
Renal (malaise, anorexia, renomegaly, azotaemia)
Cutaneous lymphoma in cats usually takes which form?
Non-epitheliotropic
Is cutaneous lymphoma in cats responsive to chemotherapy?
Generally no
How do you diagnose lymphoma in cats?
FNA
Excisional/wedge biopsy of node
Which types of lymphoma in cats are more likely to be high grade?
Cranial mediastinal
Extranodal
Alimentary
How do you treat lymphoma in cats?
No treatment
Corticosteroids
Multi-drug chemotherapy (high dose COP is best for cats)
What is the mean survival time for cats with lymphoma without therapy?
What about with high dose COP?
4 weeks
COP: 1 yr=49%, 2 yr=40%
Give some side effects of chemotherapy in cats
Myelosuppression (check haem prior to every bolus) (intermittently check urine in case of UTIs) Hair loss (whiskers) GI signs
What must you do in a cat with alimentary lymphoma when surgically excising the mass lesion?
Biopsy lymph nodes (even if they look normal)
What supportive therapy can you give to a cat with alimentary lymphoma?
Vitamin B12 (as disease is malabsorptive) Appetite stimulants
What rescue therapy can you use in cats with lymphoma?
Doxorubicin or Lomustine
What is a rescue therapy?
Drug given when animal develops a drug resistance to chemotherapy drugs and relapses
What is leukaemia?
Neoplastic proliferation of WBCs in bone marrow which then enters systemic circulation
How is leukaemia classified?
By cell type and progression
Acute vs chronic
Lymphoid or myeloid
What is the prognosis like for acute feline leukaemias?
Poor
Weeks-months when with chemotherapy
What treatment is available for acute feline leukaemia?
Supportive therapy: blood transfusion, antibiotics, barrier nursing
Multi-drug chemotherapy (addition of cytarabine infusions may improve response)
Chronic leukaemia in cats is more commonly a proliferation of which cell?
T cell
How do you treat chronic leukaemia in cats?
What is the survival time?
Prednisalone/chlorambucil
1-3 years
How do you diagnose leukaemia?
Haematology with manual differential and smear evaluation
Flow cytometry of peripheral blood to determine if lymphoid or myeloid
Staging to evaluate extent of disease (thoracic radiographs, abdominal US, cytology of liver/spleen)
Bone marrow biopsy (cytology plus histology)
What is multiple myeloma?
Systemic neoplastic proliferation of plasma cells
Results in overproduction of antibody (IgA or IgG)
Give some clinical signs of multiple myeloma?
Hyperproteinemia which can lead to hyperviscosity syndrome (neuro symptoms, retinal detachment, congestive heart failure, hypertension, coagulopathy)
Bone marrow involvement can lead to cytopenias
Renal disease in 33-50% of dogs
Hypercalcaemia
Hyperglobulinaemia
Proteinuria
May see circulating plasma cells on haematology
How do you diagnose multiple myeloma?
Haematology, biochemistry, urinalysis
Serum protein electrophoresis
Imaging (hepatosplenomegaly)
Cytology: liver, spleen, bone marrow
In order to be diagnosed with multiple myeloma, dogs need to fulfil two of which four criteria?
- Monoclonal gammopathy (prescence of M protein- produced by plasma cells- in blood)
- Radiographic evidence of osteolytic bone lesions
- > 5% neoplastic plasma cells or >10-20% plasmacytosis in bone marrow)
- Bence-Jones proteinuria
What treatment can you use for multiple myeloma?
Supportive care:
- Blood transfusions
- Plasmapheresis
- Antibiotics if secondary infection
- Therapy for hypercalcaemia
Systemic disease:
- Prednisolone
- Chemotherapy (prednisolone plus Melphalan)
Local extramedullary plasma cell disease may be treated surgically if no systemic involvement
What are the 3 immunophenotypes of lymphomas?
B-cell
T-cell
Null phenotype (neither T nor B)
What has a better prognosis: B-cell phenotype lymphoma or T-cell phenotype lymphoma?
B-cell
‘B-cell is better, T-cell is terrible’
Give the 5 stages of lymphoma
1: Single lymph node/organ affected
2: Many lymph nodes affected in 1 half of the body
3: Generalised lymph nodes affected
4: Hepatic and/or splenic involvement
5: Bone marrow/blood/CNS involvement
How do you carry out staging of lymphoma?
Haematology (abnormal cells on smear-may see large blast cells instead of normal lymphocytes)
Biochemistry (hypercalcaemia in dogs, look for neutropenia which would indicate myelosuppression and bone marrow involvement)
Aspirate or biopsy of lymph nodes
Thoracic radiographs, abdominal US
Bone marrow biopsy
What is the medial survival time for dogs with lymphoma who don’t receive any treatment?
4-6 weeks if asymptomatic
What is the medial survival time for dogs with lymphoma who are on prednisolone alone?
1-2 months
High dose COP is made up of which drugs?
Cyclophospamide
Vincristine (onchovine)
Prednisolone
What is the medial survival time for dogs with lymphoma who receive high dose CHOP treatment?
10-12 months
Why may epirubicin be used instead of doxorubicin in COPH treatment for lymphoma?
Doxorubicin can affect heart contractility
Give some side effects of chemotherapy in dogs
GI toxicity: vomiting, diarrhoea, nausea (chemotherapy kills rapidly dividing cells eg cells in gut lining)
Myelosuppression: neutropenia, thrombocytopenia, anaemia
Sterile haemorrhagic cystitis (cyclophospamide)
Cardiotoxicity (doxorubicin)
Hepatotoxicity (Lomustine)
Surgery for lymphoma in dogs could be considered for which types?
Early stage 1 disease
Rare Hodgkins lymphoma
Possibly extranodal lymph one
What should you consider when treating CNS lymphoma?
Many drugs do not penetrate the BBB
Which drugs can be used to control clinical signs of cutaneous lymphoma?
Retinoids (related to vitamin A, regulate epithelial cell growth)
What rescue protocols can you use in dogs with lymphoma?
DMAC (dexamethosone, Melphalan, actinomycin-D, citarabine
CCNU (Lomustine), L-asparaginase, prednisolone
Single agent anthracyclines (doxorubicin/Epirubicin if not already in COP protocol)
How often should you see patients who are in complete remission and no longer on treatment for lymphoma?
Monthly at least for the first 6 months, then every 2-3 months
When should you restage lymphoma?
When there are no sentinel lymph nodes to follow
When patient is not doing as well as expected/clinical signs don’t resolve
At the end of an induction phase
At the end of a discontinuous protocol
Give some GI problems seen with neoplasia
Cancer cachexia/ sarcopenia complex
Cancer anorexia
Gastro-duodenal ulceration
Protein-losing enteropathy
How does cancer cachexia/sarcopenia and anorexia occur?
- Cancer cells preferentially use glucose for energy. Poor tumour blood flow leads to anaerobic respiration -> increased lactate production and altered insulin sensitivity
- Cancer related cytokine production and inflammation can affect metabolism
- Some patients suffer poor appetite but can see changes even with normal appetite
Give some clinical signs of cancer cachexia/ sarcopenia and anorexia
Weight loss, reduced fat mass, lean muscle loss, poor tolerance of treatment
How can you treat cancer cachexia/sarcopenia and anorexia?
Maintain/increase calorific intake by giving low carbohydrate, high fat diet
Omega 3 PUFA may be beneficial in reducing inflammation related changes
Why do GI tumours often have associated gastric or duodenal ulceration?
Due to poor blood supply and altered wall structure (can rupture or bleed-> anaemia)
Some tumours produce hormones/metabolites -> gastric acid -> ulceration (eg gastronomas)
Dogs with mast cell tumours have elevated what in their blood?
Give some consequences
Histamine
Can causes GI signs, ulceration and bleeding
Describe protein-losing enteropathy in dogs with cancer
Not specific for cancer but seen particularly with GI lymphoma
Diffuse GI lesions can allow protein loss
Low total protein, globulin and albumin, often with diarrhoea
Low albumin can lead to ascites
Other effects due to loss of proteins that bind hormones, clotting factors etc
How does acute and chronic anaemia occur with neoplasia?
Acute: systemic effect due to haemorrhage from a tumour
Chronic: systemic effect due to low grade haemorrhage from a tumour, or systemic effect secondary to PNS ie excess histamine/gastrin -> ulceration
Give some clinical signs of acute blood loss anaemia associated with neoplasia
Hypovolaemia
Shock
Anaemia initially non-regenerative then becomes regenerative
Give some clinical signs of chronic blood loss anaemia associated with neoplasia
Lethargy
Pallor
Poorly regenerative microcytic hypochromic anaemia due to iron deficiency
What is myelopthisis/myelopthisic anaemia?
Which cytopenias are seen?
How do you diagnose?
Crowding out of stem cells in the bone marrow by tumour cells
Tumours might produce suppressive cytokines
Neutropenia then thrombocytopenia then non-regenerative anaemia (normochromic, normocytic)
Diagnose by bone marrow aspirate
What is a common cause of non-regenerative anaemia?
Chronic inflammatory disease
Anaemia is due to disordered iron storage, and shortened RBC life span
Cancer is a cause
Give some clinical signs of hyperoestrogenism caused by testicular tumours
Initially neutrophilia then bone marrow hypoplasia
Neutropenia, thrombocytopenia, non-regenerative anaemia
Feminisation signs, symmetrical alopecia, pendulous prepuce, hyperpigmentation, penile atrophy, gynecomastia, prostatic metaplasia
What clinical sign is typical of immune-mediated disease?
Petecchiation
Give a tumour type that can cause microangiopathic anaemia
Haemangiosarcoma
How does microangiopathic anaemia occur?
Fragmentation and shearing of RBCs caused by fibrin networks
Schistocytosis is a key indicator