Flashcards in Oncology - Osteosarcoma and Hemangiosarcoma Deck (60)
What is an osteosarcoma?
It is a malignant mesenchymal tumor of primitive bone that produces an extracellular osteoid matrix
True or False: Osteosarcoma is the most common skeletal malignancy in dogs.
What type of age distribution does osteosarcoma have?
Bimodal - young dogs, and old dogs
What breeds more commonly get osteosarcomas?
Large/Giant Breed dogs
What legs usually get osteosarcomas more commonly?
Where do osteosarcomas more commonly happen?
at the metaphysis
What are the developmental factors that can lead to osteosarcoma?
Large, fast growing dogs
Dogs who get ionizing radiation
How are osteosarcomas diagnosed?
Is cytology or a biopsy necessary for osteosarcoma diagnosis?
It has decent accuracy of determining malignancy and an average accuracy of determining tumor type Can fracture
Long story short - not entirely necessary
Is a definitive diagnosis of osteosarcoma needed before treatment?
no - any other lesion that could be caused there may be treated similarly
If you are doing radiation - no
What should be done for staging?
3 view chest rads
Bone scan is not helpful
What percentage of cases have micrometestatic disease at diagnosis of osteosarcoma?
What is osteosarcoma grading based on?
Amount of pleomorphism, tumor cell appearance, MI, and necrosis
What grade of osteosarcoma has the highest risk of death
What are subclassifications of osteosarcoma based on?
the type and amount of matrix, may impact survival
What is a stage I OSA?
Low grade, no metastasis
What is a stage II OSA?
high grade, no metastasis
What is a stage III OSA?
Low or high grade, mets
What is a stage A OSA?
What is a stage B OSA?
What stage and grade are most dogs that we diagnose with OSA?
What are the treatment options for OSA?
Surgery, radiation, chemotherapy, and pain control
What is the recommended surgery for OSA?
Amputation - this does nothing for the metastasis
What is limb spare?
You take the tumor out and replace it with something - can only do for distal radial osteosarcoma
What radiation therapy options are there for osteosarcoma?
Palliative and stereotactic
What is something important to keep in mind about stereotactic therapy and OSA?
The leg will fracture within a year
What is the chemotherapy of choice for OSA?
Carboplatin (less side effects) or doxorubicin
What can be done to remove pulmonary metastatic disease associated with OSA?
What criteria are there for pulmonary metastasectomy?
Stable primary disease for 300 days
3 lesions or less
Radiographic doubling time for >40 days
No other evidence of disease