SA MED - ONCOLOGY EXAMS Flashcards
If a new vaccine were developed to treat a particular tumor in dogs, it is most likely to be effective:
- when disease burden is high with a large tumor present
- when there are detectable metastatic lesions present
- when there is minimal disease present
- if it is given along with immune suppressive therapy such as high doses of prednisone
When there is minimal disease present
Characteristics of malignant cells according to Hanahan and Weinberg include:
- insensitivity to growth signals
- limited replicative potential
- tissue invasion and metastasis potential
- inability to promote angiogenesis
Tissue invasion and metastasis potential
Malignant transformation of cells can occur due to mutation in DNA or an epigenetic change that leads to changes in the cells causing:
- increased apoptosis in the cells
- suppression of oncogenes in the cells
- activation of tumor suppressor gene cells
- alteration of DNA repair capabilities in the cells
Alteration of DNA repair capabilities in the cells
Taking a small piece of tissue from a mass is referred to as an “incisional biopsy.” An advantage to doing an incisional biopsy versus an excisional biopsy is:
- to determine what further staging tests may be needed prior to removing the mass
- negligible, the mass should just be removed in total as the first diagnostic step
- to reduce the total amount of tissue you will need to remove later
- the biopsy results will always be more accurate on a small piece of tissue versus the whole mass
To determine what further staging tests may be needed prior to removing the mass
Abdominal ultrasound is an especially important test for staging if:
- the tumor is a carcinoma in the oral cavity
- the tumor is a round cell tumor and local therapy is possible
- the tumor is a high-grade sarcoma on a front foot
- the tumor is an osteosarcoma and lung metastases have already been noted
The tumor is a round cell tumor and local therapy is possible
Saying a treatment for a tumor will give a median survival of 1.5 years means:
- 75% of dogs receiving the treatment will die within the first year after the time of diagnosis
- all dogs receiving the treatment will die within 1.5 years after the end of treatment
- some dogs receiving the treatment will live more than 2 years from the time of diagnosis
- at 1.5 years 50% of dogs will have died from their tumor whether they received treatment or not
Some dogs receiving the treatment will live more than 2 years from the time of diagnosis
With an osteosarcoma of the distal radius in a 10-year-old mixed breed male neutered dog:
- with chemotherapy alone the dog will probably have 1 year of good quality of life
- with amputation alone the dog will probably have one year of good quality of life
- with palliative radiation alone the dog will probably have one year of good quality of life
- none of the above are probable
None of the above are probable
You are treating a dog with a chemotherapy protocol which involves weekly treatments with a rotating schedule of Vincristine, Cyclophosphamide, and Doxorubicin. Vincristine is the drug to be given today but is temporarily unavailable. Which drug/drugs would be reasonable substitutes?
- Cyclophosphamide
- Doxorubicin
- Vinblastine
- Lomustine
Vinblastine
Based on several studies, approximately what are the chances that a dog living to the age of ten years or beyond will die of cancer?
- 10%
- 20%
- 45%
- 70%
45%
Which of the following characteristics is most typical of a malignant lesion rather than a benign lesion?
- distinct borders of the lesion
- presence of similar abnormal cells in the draining lymph node
- dysfunction caused by compression of adjacent normal structures
- mitotic index of two mitoses per ten high power fields
Presence of similar abnormal cells in the draining lymph node
What is the purpose of requesting a determination of tumor grade from a pathologist?
- predict the cause of the tumor
- predict the likelihood of complete excision
- predict the likelihood of metastasis
- predict the response to chemotherapy
Predict the likely hood of metastasis
Hypertrophic osteopathy is associated with what condition?
- osteodestructive tumors
- large breed, rapidly growing dogs
- pulmonary masses
- central nervous system tumors
Pulmonary masses
The presence of an enlarged internal iliac lymph node on abdominal ultrasound should suggest that a tumor hunt be focused on which anatomical location?
- cranial mammary glands
- intestinal tract
- liver and spleen
- perianal region
Perianal region
Which of the following contributes most significantly to cancer cachexia?
- decreased oral intake of food due to side effects of chemotherapy drugs being given
- inefficient glucose utilization by tumors
- poor absorption of nutrients due to the tumor’s effect on the GI tract
- having too much grain in the diet
Inefficient glucose utilization by tumors
Metronomic chemotherapy can exert its anti-tumor effects in cancer patients via several mechanisms. Which of the following is not likely?
- resolution of immune dysregulation by suppression of T regulatory cells
- inhibition of angiogenesis by inhibiting endothelial cell mobilization
- inhibition of receptor tyrosine kinases
- tumor cell growth suppression by constant low-dose exposure to chemotherapy
Inhibition of receptor tyrosine kinases
Which drug would you most consider for treatment of high grade B cell lymphoma in a dog if the owner only wanted to use one drug?
- Chlorambucil
- Cytosine arabinoside
- L-aspariginase
- Doxorubicin
Doxorubicin
When dealing with cats with tumors, performing radical surgery from the start is usually important for most tumor types except:
- mammary tumors
- vaccine associated sarcomas
- cutaneous mast cell tumors
- cutaneous squamous cell carcinomas
Cutaneous mast cell tumors
Side effects of radiation therapy:
- are related to how fast a treated tissue is normally dividing
- are related to the type of tumor being treated
- are the same in all tissues normal or neoplastic
- tend to be more severe when therapy is spread out over a long period of time
Are related to how fast a treated tissue is normally dividing
Regarding mast cell tumors in dogs:
- when a dog presents with a mass diagnosed via cytology as a mast cell tumor an ultrasound guided aspirate of the spleen should always be done prior to trying to remove the mass
- mast cell tumors arise as primary tumors in the abdominal cavity as frequently as they arise in the skin
- a biopsy is needed to determine the grade of the tumor and to help define appropriate staging tests and therapy
A biopsy is needed to determine the grade of the tumor and to help define appropriate staging tests and therapy
A 20-year-old mixed breed dog presents with enlarged mandibular, scapular and axillary lymph nodes and you diagnose high grade lymphoma from a fine needle aspirate and cytology. The dog is happy and has no other clinical signs. With no further diagnostics this dog would be staged at least:
- Stage II A
- Stage III A
- Stage II B
- Stage III B
Stage II A
An owner brings their Rottweiler with a soft tissue sarcoma diagnosed at another veterinarian on the lower front limb to you for treatment options. The mass is roughly 2x2 cm and overlies the carpus. The owner does not want a biopsy - they just want it removed. You explain to the owner that options for treatment could be:
- remove the mass but if clean margins are not attained they will need follow-up therapy, preferably with radiation therapy
- remove the mass but if clean margins are not attained follow up high dose chemotherapy would be curative
- remove the mass but if clean margins are not attained the leg would need to be amputated as soon as possible or the tumor will metastasize
- the mass is so small there is no need to remove it as it is not bothering the dog at this time
Remove the mass but if clean margins are not attained they will need follow-up therapy, preferably with radiation therapy
If you were trying to invent a tumor cell line that was very sensitive to chemotherapy (and therefore all your new drugs would appear very efficacious) what necessary characteristics would be required?
- exponential growth rate and genomic stability
- slow growth rate and genomic stability
- exponential growth rate and an unstable genome
- slow growth rate and an unstable genome
Exponential growth rate and genomic stability
Which of the following is inappropriately linked with a paraneoplastic syndrome?
- lymphoma and hypercalcemia
- pancreatic tumor and myasthenia gravis
- nasal fibrosarcoma and polycythemia
- apocrine gland adenocarcinoma of the anal sac and hypercalcemia
Pancreatic tumor and myasthenia gravis
A 9-year-old mixed breed dog presents with a subcutaneous mass on the lateral left thigh about 2x3 cm in size. The owner wants you to remove it so you do your best but you warn the owner that if you do not know what it is ahead of time it is difficult to predict how successful your surgery will be. you do the surgery and send in the mass for histopathology. The results of pathology say the mass is subcutaneous hemangiosarcoma and surprisingly you achieved 1 cm clean margins in all directions. The owner is happy but you now have to tell them this tumor may also be in other locations and you need to do some staging. Which group of tests is needed and appropriate though possibly not complete?
- cardiac echo, abdominal ultrasound, bone marrow aspirate
- thoracic radiographs, abdominal ultrasound, bone scan
- cardiac ultrasound, thoracic radiographs, abdominal ultrasound
- cardiac echo, abdominal ultrasound, serum protein electrophoresis
Cardiac ultrasound, thoracic radiographs, abdominal ultrasound