Oncology Flashcards
What are the physical examination tests for determining nasal air flow patency in a dog or cat?
- Listen with a stethoscope
- Use a slide to watch for condensation
- Feel by blocking one nostril at a time
- CT scan
These tests help assess nasal obstruction.
What are the different biopsy techniques for an intranasal mass in a dog or cat?
- Rhinoscopy gives small samples
- Hydropulsion (60ml bulb syringe) can give out big chunks
- Rhinotomy, bloody and last resort
Each technique has its own advantages and disadvantages.
What is included in a diagnostic plan for a mediastinal mass in a dog or cat?
- Ultra-sound guided FNA
- Cytology to determine if it is a thymoma or lymphoma
- Flow cytometry to differentiate between t-lymphocytes
- Pre-op thoracic CT scan if it is a non-lymphoma diagnosis
This plan helps in identifying the nature of the mass.
What diagnostic tests should be run if hypercalcemia is suspected due to paraneoplastic syndromes?
- Ionized calcium
- PTH
- PTHrp
These tests help rule out other differentials for hypercalcemia.
What are the paraneoplastic syndromes associated with thymomas?
- Myasthenia gravis +/- megaesophagus
- Polymyositis
- Erythema multiforme
- Arrhythmias
- Other immune disorders
- Exfoliative dermatitis (cats)
Myasthenia gravis can occur due to impaired neuromuscular transmission.
What is the typical location of a solitary lung mass in a dog or cat?
Often in the caudodorsal lung fields
Evaluation of lymph nodes and checking for pleural effusion is also necessary.
What are the limitations of thoracic CT imaging for solitary lung nodules?
CT Scan is sensitive but cannot distinguish resectability or inform of invasiveness/adhesions
A lung lobectomy is often the treatment of choice.
What is the best method for obtaining a histological diagnosis of an oral mass in a dog?
Biopsy incisional is best
FNA in oral masses is difficult due to infection and inflammation.
What is the expected dose for surgical resection of oral tumors in dogs involving the maxilla or mandible?
If it touches bone, the bone has to go
Common tumors include fibrosarcoma, melanoma, and SCC.
What are the anticipated risks and needs for a dog undergoing maxillectomy or mandibulectomy?
- Intraoperative risks
- Perioperative risks
- Postoperative risks
- Soft dog food, low key activity for two weeks, no objects in the mouth for a month
Most dogs recover quickly, eating the night of surgery.
What is a ‘hi-low’ fibrosarcoma?
‘Hi-low’ is a histologically low grade but biologically high grade fibrosarcoma
It can be misdiagnosed and requires larger surgical margins despite having a low metastatic rate.
What is the surgical approach for solitary versus diffuse intestinal lesions in dogs or cats?
- Solitary masses require surgery
- Diffuse requires chemotherapy
This distinction is important for treatment planning.
What is the diagnostic plan for unknown gastrointestinal masses during an exploratory surgery?
Resect what you can and biopsy other lesions
This helps in determining the nature of the masses.
What are the differential diagnoses for perianal tumors?
- Incidental finding (check anal glands)
- Mass effect in perineal region
- Bleeding/discharge
- Excessive licking
- Tenesmus/abnormal shaped feces
- Fecal/urinary obstruction
- PU/PD
Understanding the presentation is key for diagnosis.
What is the role of surgery in the treatment of perianal tumors?
Surgery is indicated unless there is invasion into musculature or extensive seeding to the abdominal wall
CT can help decide which cases are surgical.
What are the median survival times (MST) for small (<3.2cm) AGASACA tumors with no metastasis?
MST 1237d with no chemotherapy
This is based on findings from Skorupski et al. 2018.
What is the MST for stage 3b tumors treated with surgery versus radiation?
- Surgery: MST 182d
- Radiation: MST 447d
This raises the question of whether radiation should be the first option.
What is the MST for distant metastasis in perianal tumors?
MST 71-82d
This highlights the poor prognosis associated with distant metastasis.
What are Soft Tissue Sarcomas (STS)?
Tumors arising from mesenchymal tissues (connective, muscle, fat, nerve sheath)
Mesenchymal tissues are the supportive tissues of the body.
What is the local behavior of Soft Tissue Sarcomas?
Locally invasive with a pseudocapsule, high risk of recurrence if not excised completely
What is the metastatic potential of Soft Tissue Sarcomas?
Low metastatic potential, primarily to lungs
Name common subtypes of Soft Tissue Sarcomas.
- Fibrosarcoma
- Peripheral nerve sheath tumor
- Liposarcoma
- Myxosarcoma
What is the goal for surgical margins during Soft Tissue Sarcoma resection?
Wide surgical excision with 2–3 cm lateral margins and 1 fascial plane deep
Why are surgical margins important in Soft Tissue Sarcoma resection?
Margins reduce recurrence risk. Incomplete margins warrant additional treatment.
What is the preferred therapeutic option for incompletely excised Soft Tissue Sarcoma?
Second Surgery: Preferred for achieving wide margins
What therapeutic options are available for incompletely excised Soft Tissue Sarcoma?
- Second Surgery
- Radiation Therapy for local control
- Chemotherapy for high-grade tumors or metastatic disease
What is the 3-2-1 Rule for managing injection-site sarcomas in cats?
- 3 months: Persistent lump after 3 months
- 2 cm: Lump is greater than 2 cm in diameter
- 1 month: Lump increases in size after 1 month
What diagnostic tool is essential for definitive diagnosis of Osteosarcomas?
Incisional biopsy
What do radiographs show in Osteosarcomas?
Mixed lytic and proliferative lesions with cortical destruction
Where should an incisional biopsy be performed in Osteosarcomas?
Avoid biopsy in the periphery of the lesion; target central areas for a better sample
What is the curative-intent treatment plan for Osteosarcomas?
Amputation of the affected limb combined with adjuvant chemotherapy
Name chemotherapy agents used in the treatment of Osteosarcomas.
- Carboplatin
- Cisplatin
- Doxorubicin
What is a limb-sparing surgery?
An option for specific locations (distal radius) in Osteosarcoma treatment
What are the causes of mortality with palliative care in Osteosarcomas?
Pain and pathological fractures
What are the causes of mortality with curative-intent therapy in Osteosarcomas?
Metastatic disease, particularly to lungs
What are the median survival times for Osteosarcomas without treatment?
1-3 months
What is the median survival time with amputation only for Osteosarcomas?
4-6 months
What is the median survival time with amputation plus chemotherapy for Osteosarcomas?
10-12 months
Does palliative therapy extend survival in Osteosarcomas?
No, it provides relief but does not extend survival significantly.
