Neoplasia Flashcards
Describe the characteristics of primary renal tumours
- Relatively uncommon
- Often solitary
- Often unilateral
- Unilateral tumour will not cause azotaemia
Name the benign primary renal tumours that may occur
- Adenoma
- Fibroma
- Haemangioma
- Interstitial cell tumour
- Leiomyoma
Name the malignant primary renal tumours that may occur
- Adenocarcinoma/carcinoma
- Lymphoma
- Fibrosarcoma
- Haemangiosarcoma
- Leiomyosarcoma
- Transitional cell carcinoma
- Cystadenocarcinoma and nodular dermatofibrosis (GSDs)
Outline the characteristics of renal tumours in dogs
- Adenocarcinoma most common primary tumour
- Often unilateral
- Middle aged and older dogs
- Males > females
Outline the characterstics of renal tumours in cats
- Lymphoma most common, can be primary or secondary
- 6-7yo
- FeLV is a risk factor, need to test
- Renal adenocarcinoma common primary tumour
Describe nephroblastomas
- Embryoma
- Most commonly dogs <1year
- May be in only one pole of an affected kidney
- Demonstres mixed tissues histologically (muscle, cartilage etc.)
- Surgery may be curative
Outline the clinical signs of renal tumours
- Often vague: anorexia, depression, weight loss, lethargy
- May have palpable abdominal mass/masses
- Haemturia throughout urination
- Abdominal pain or distension
- Development of pelvic limb oedema if lymphatic drainage compromised
What may be found on blood biochemistry and haematology with a renal tumour?
- Often unremarkable
- Regenerative anaemia if haematuria
- Azotaemia if bilateral
- HyperCa as paraneoplastic (uncommon unless lymphoma)
- Rarely may be polycythaemic
What may be found on urinalysis with a renal tumour?
- Proteinuria
- +/- haematuria
- Neoplastic cells very uncommon
What may be found on imaging with a renal tumour?
- Renomegaly may be seen on radiographs
- Ultrasonography usually better
List the differentials for a mass in the region of the kidney
- Neoplasia
- Cyst
- Granuloma
- cPSS, pyelonephritis, AKI, amyloidosis (generally not distinct masses)
Give a brief overview of the approach to a mass in the region of the kidney
- Identify location ie. renal, adrenal, other?
- Rule in/out differentials
- Tissue sampling to diagnose as benign or malignant
- If malignant, met check: palpate bones, LNs, and imaging of thorax
Discuss the tissue sampling of a renal mass
- Aspirate, trucut or surgical biopsy
- Not always diagnostic
- If cavitated mass, may not get a representative sample
- Referral may be needed
Outline the treatment of renal tumours
- Nephrectomy +/- chemo (unless lymphoma)
- Not always curative - carcinoma MST 8mo, sarcoma MST 5mo post removal
- Nephroblastoma cured by removal
Discuss the presentation of renal lymphoma in dogs and cats
- Cats: 7.5yo, may be FeLV +ve, may have systemic disease, may have CNS involvement, present with bilateral renomegaly and azotaemia +/- renal pain
- Dogs: less common, uni or bi lateral, often no associated clinical signs
Outline the treatment and prognosis for renal lymphoma
- Chemo: COP or CHOP, consider dose reduction depending on degree of azotaemia (renal drug excretion)
- Negative prognostic indicators: FeLV, CNS involvement, severity of renal failure
- Survival 5-13 months
Outline renal tumours in budgie
- Second most common tumour
- Often <5yo
- Uni or bilateral HL lameness/paralysis without hx of trauma
- Reduced sensation below stifle joint, abdominal enlargement, generally unwell, weight loss
- Tx: steroids (not surgery)
Name the benign and malignant tumours that may occur in the ureters
- Benign: leiomyoma
- Malignant: leiomyosarcoma
Discuss the impact of bladder tumours
- Not systemically ill generally
- Quality of life reduced due to inability to urinate
Briefly describe the characteristics of transitional cell carcinomas
- Majority of bladder tumours
- Trigone
- Usually locally invasive, may extend beyond bladder wall to organs such as vagina, uterus, prostate
- Distant mets to local LN, lung, liver spleen in 50% of cases
Outline bladder tumours in horses
- Uncommon
- Squamous > TCC
- Presentation and diagnosis as for dogs
- Laser therapy is an option for treatment
Outline bladder tumours in ruminants
- Cattle > sheep
- High prevalence if graze infested pastures long term
- Intoxication with praquilloside is cumulative
- Bovine papillomaviruses associated with development of neoplasia in cattle exposed to bracken fern
- Initially ingestion of bracken fern leads to enzootic haematuria, then bladder tumours
What is the typical signalment for bladder tumours in dogs?
- FN, mean age 10yo
- Scotties, Beagle, JR, Collies, WHWT
- Some have history of UTI
- Exposure to flea powders, dips, collars, herbicides, insecticides increases risk
What is the typical signalment for bladder tumours in cats?
- No breed predispositions
- Mean age 10yo
Describe the typical presentation of bladder and urethral tumours
- May get complete obstruction of bladder outflow (urethral more dysuric)
- Stranguria, haematuria, pollakiuria
- Lameness (bone mets, hypertrophic oestopathy)
- Cough/dysnoea (thoracic mets)
- Dysuria with no clear urinary abnormalitites
Outline the approach to urethral/bladder masses
- Distinguish urethral vs bladder
- Benign or malignant?
- If malignant, stage it
- Respond well to steroids
What diagnostic methods are useful for bladder tumours and what results are indicative?
- Urinalysis: +/- proteinuria, +/- haematuria, sometimes neoplastic cells (<30% of tumours exfoliate into urine), tumour antigen in urine (but false +ves common)
- Contrast radiography: filling defects/abnormalities
- Ultrasonography: thickened, irregular bladder wall, usually in trigone region
- Cystoscopy: direct visualisation, may see frond-like structures
- FNA, biopsy (endoscopic, or catheter suction biopsy)
What is required in order to stage a bladder/urethral tumour?
- Local LN check
- Thoracic radiographs
- Abdomnal ultrasonography
- FNA/biopsy
Outline the treatment options for urethral/bladder tumours
- Surgery (partial cystectomy)
- Palliative urinary diversion (good short term)
- Stent placement (best to pre-treat with NSAIDs and post with chemo)
- Medical management: NSAIDs, adjunctive chemo, metronomic chemo
Discuss the use of NSAIDs in the medical management of bladder tumours
- Meloxicam, piroxicam, firocoxib
- 15-20% go into partial remission, most enter stable disease
- TCCs can benefit from COX-2 inhibitors
Discuss the use of adjunctive chemo in the management of bladder tumours
- Carboplatin, doxorubicin, mitoxantrone added to NSAIDs
- Result in improved remossion rates and times in some dogs
- Carboplatin has fewer side effects, but mitoxantrone may be more advantageous
- Can continue carboplatin to manage clinical signs
Discuss the use of metronomic chemo in the management of bladder tumours
- Chlorambucil daily may help where others fail
- 70% of dogs had stable disease, median survival time 221 days
- Anti-angiogenic rather than anti-proliferative
Discuss the prognosis for bladder tumours
- Depends on site and TNM grade
- Prognosis generally poor
- Depends also on signs at presentation (few signs = better)
- Surgery MST 3mo
- NSAIDs MST ~6mo
- Combined modalities more expensive but may live longer
