Oncology

Question 1

Anal sac adenocarcinomas

Answer 1

associated with hypercalcemia

Question 2

Anal sac tumor

Answer 2

most commonly apocrine gland adenocarcinomas (need to FNA of biopsy to diagnose), masses in the 4 and 8 o’clock regions. Hypercalcemia is occasionally associated with this tumor type and dogs commonly present for tenesmus or licking around the perianal region.

Question 3

Basal cell tumor

Answer 3

represent a heterogeneous group of cutaneous epithelial neoplasms recognized most commonly in cats, less commonly in dogs, occasionally in horses and sheep, and seldom in other domestic animals. These neoplasms are composed of a proliferation of small basophilic cells that exhibit morphology reminiscent of the progenitor cells of the epidermis and adnexa. As these tumors have been examined more closely, evidence of differentiation (follicular, sebaceous, etc) has been discovered, giving justification for reclassification. For example, in dogs, what in the past was called a basal cell tumor is best characterized as a trichoblastoma, a tumor of hair bulb (the site of the follicle that produces the hair shaft) origin.

Question 4

Carcinoma

Answer 4

These tumors come from epithelial cells including cells of glandular tissue such as salivary glands, mammary glands, and cell lining most tissues including squamous cell or transitional cells. The cytologic appearance is that of cohesive clusters of cells. Cells are often polygonal in shape.

Question 5

CHOP chemotherapy protocol

Answer 5

Cyclophosphamide, vincristine, doxorubicin, and prednisone are the drugs in a CHOP chemotherapy protocol used to treat dogs and cats (and people) with high grade or large cell lymphoma, which more commonly manifest as a large focal mass rather that diffuse thickened intestines.

Question 6

Erythropoietin secretion

Answer 6

associated with renal carcinomas, causing elevations in hematocrit as a paraneoplastic syndrome

Question 7

Hemangiosarcoma

Answer 7

right atrium in dog most commonly affected, associated with thrombocytopathy. Can results in cardiac tamponade from excessive accumulation of fluid in the pericardium resulting in an increased intrapericardial pressure impairing diastolic filling of the heart.

Question 8

Histiocytic sarcoma

Answer 8

common in dogs and rare in goats and cattle; it is debatable whether they are found in cats. Strong immunohistochemical evidence suggests that in dogs they are derived from Langerhans (intraepidermal antigen processing) cells. These tumors are typically seen in dogs <3.5 yr old but can be seen at any age. English Bulldogs, Scottish Terriers, Greyhounds, Boxers, and Boston Terriers are most at risk. The head (including the pinnae) and limbs are the most common sites of involvement. These classic “button tumors” appear as solitary, smooth, pink, raised nodules that are generally covered by alopecic skin, or they may be ulcerated. They are freely movable. Although a common neoplasm, histiocytomas are not always easy to diagnose histologically and can be confused with granulomatous inflammation, mast cell tumors, plasmacytomas, and cutaneous lymphosarcomas. Canine histiocytomas should be considered benign, and most resolve spontaneously within 2–3 mo without treatment. Surgical excision is optional once the diagnosis is established (which can often be made via cytology).

Question 9

Histiocytomas

Answer 9

typically benign and will often present as a small, raised mass that may or may not be ulcerated. Fortunately, these masses usually regress on their won, and surgical or medical intervention is typically not necessary.

Question 10

Hyperadrenocorticis

Answer 10

caused by functional adrenal or pituitary tumors

Question 11

Hypercalcemia

Answer 11

associated with anal sac adenocarcinomas, lymphomas and other tumors

Question 12

Hyperestrogenism

Answer 12

can be seen with Sertoli cell tumors

Question 13

Hypertrophic osteopathy

Answer 13

Due to pulmonary neoplasia

Question 14

Lymphomas

Answer 14

associated with hypercalcemia, first treatment option for cats is an L-asparaginase trial.

Question 15

Mammary tumors

Answer 15

Almost always malignant and will eventually metastasize in cats and about 50% in dogs of which on 50% will eventually metastasize. tumor >2 cm is a negative prognostic indicator in cats.

Question 16

Mast cell tumour

Answer 16

associated with causing GI ulcers (histamine via activation of H2 receptors or gastric parietal cells), perioperative hypertension, and coagulation abnormalities. Do not use morphine in patient with MCT due to significant histamine release, butorphanol and ketamine do not, acepromazine has some histamine. MCT release histamine, heparin (causes coagulopathy), and other vasoactive amines (with histamine leads to vasodilation and hypotension).

Question 17

MCT high grade - treatment

Answer 17

Start a tyrosine kinase inhibitor chemotherapy drug

Mast cell tumors are highly responsive to radiation therapy, but with clean excision and wide surgical margins, local recurrence is unlikely. Metastasis is the primary concern and a wait and monitor approach is not advised. Even with no evidence of metastasis at the time of surgery, chemotherapy should be initiated as soon as possible. Common protocols include single agent or alternating vinblastine and lomustine. Tyrosine kinase inhibitors target c-kit, a stem cell factor receptor involved in mast cell proliferation and differentiation.

Question 18

Most common intranasal tumor in cat

Answer 18

lymphosarcoma

Question 19

Most common intranasal tumor in dog

Answer 19

Adenocarcinoma

Question 20

Multiple myeloma

Answer 20

Associated with thrombocytopathy

Question 21

Nasal Adenocarcinoma

Answer 21

nasal plane of dog

Question 22

Ocular squamous cell carcinoma bovine

Answer 22

“cancer eye” heritable in cattle

Question 23

Osteosarcoma

Answer 23

diaphysis most common site of origin

most common primary bone tumor is osteosarcoma that affects the distal radius, proximal humerus, distal femur, or proximal tibia.

Question 24

Papillomas in Saanen goats

Answer 24

Tend to transform into squamous cell carcinomas

Question 25

Patnaik grading system

Answer 25

Grade 3 tumors are highly metastatic.

Question 26

Peripheral nerve sheath tumour

Answer 26

soft tissue/low grade

Question 27

Primary Intraocular tumor in cow

Answer 27

squamous cell carcinoma

Question 28

Primary Intraocular tumor in dogs and cats

Answer 28

melanoma

Question 29

Renal cacinoma

Answer 29

associated with polycythemia, erythropoietin secretion, causing elevations in hematocrit as a paraneoplastic syndrome

Question 30

Round cell tumors

Answer 30

There are 5 round cell tumors and most, but not all, come from blood cells. They are lymphoma, mast cell tumors, plasma cell tumors, histiocytic tumors, and transmissible venereal tumors. Remember, these are sometimes also referred to as sarcomas (i.e. lymphosarcoma or histiocytic sarcoma). Cytologically, they appear usually as large populations of cells that are not in defined clusters. The cells have a round shape, often with unique identifiable features such as the purple granules in mast cell tumors.

Question 31

Sarcoma

Answer 31

These tumors come from mesenchymal cells and are named by the specific cell type such as fibroblast (fibrosarcoma) and osteoblasts (osteosarcoma). Cytologically, they tend to appear as isolated spindle-shaped cells with elongated cytoplasm and often oval nuclei.

Question 32

Sebaceous Gland Tumour is dog

Answer 32

most common type of skin tumour - ulcerated

Question 33

Sertoli Cell Tumours

Answer 33

estrogen secreting (hyperestrogenism), cause budgerigar to change color from blue to brown. Quite common in dogs with cryptorchid testes and cause the clinical signs of truncal alopecia, hyperpigmentation, gynecomastia, urinating in a female position, and bone marrow dyscrasias such as aplastic anemia.

Question 34

Small Cell (low-grade) intestinal lymphoma

Answer 34

Considered an indolent or slow progressive form of lymphoma and can be effectively treated with chlorambucil and prednisolone. This form of lymphoma is sometimes thought to develop from the progression of inflammatory bowel disease in cats. Chlorambucil is an oral alkylating agent that is usually well tolerated with few side effects. Many cats live several years with this form of lymphoma and this treatment.

Question 35

Thrombocytopathy

Answer 35

can be seen with hemangiosarcoma and multiple myeloma

Question 36

Thymoma

Answer 36

Tensilor response test

Question 37

Transitional cell carcinoma of the bladder

Answer 37

In dog, palliatively manage with non-steroidal anti-inflammatory drugs such as piroxicam. Progression-free interval and survival can be extended with the addition of chemotherapy. The most commonly used agents are carboplatin, cisplatin, and mitoxantrone. Although cisplatin is effective against TCC, is has increased nephrotoxicity with piroxicam and is less commonly used these days. Secondary infections can be treated with appropriate antibiotics