Lecture 5

Question 1

What is the definition of canine lipoma

Answer 1

A benign subcutaneous mass with a soft texture usually localized.

Question 2

Who does canine lipoma affect

Answer 2

Most commonly dogs, rare in cats and horses
Breed predispositions
Hypothyroid dogs

Question 3

What are the clinical signs of canine lipoma

Answer 3

Palpation of small, soft mass under the skin
Should not cause discomfort to the patient
Usually around abdominal region but can be anywhere
Tendency to develop multiple

Question 4

How do you diagnose canine lipoma

Answer 4

Fine needle aspiration

Surgical removal and histopathology

Question 5

How do you treat canine lipoma

Answer 5

Surgical removal can be done but it is not necessary unless it is restricting movement

Question 6

Describe basal cell tumor

Answer 6

Has many specific names
Mid to old dog and cat
Mostly on head and neck

Question 7

Describe follicular tumor

Answer 7

Often inflammation
Older dogs
Can sometimes squeeze out material

Question 8

Describe sebaceous adenoma

Answer 8

Cauliflower-like tumor
Older cats & dogs
ideally should be removed
malignant version exists

Question 9

describe soft tissue sarcoma

Answer 9

General name for a number of mesenchymal tumors
Muscle, adipose, neurovascular, fascial, and fibrous tissue
Mostly malignant (see grade)
Similar pathologic appearance and clinical behavior
Solitary tumor in older dogs and cats
Skin and subcutaneous sites are most common

Question 10

describe the soft tissue sarcoma

Answer 10

Tend to appear as pseudoencapsulated soft-to-firm tumors, but have poorly defined histologic margins or infiltrate through and along fascial planes, and they are locally invasive.
Local recurrence after conservative surgical excision is common
Tend to metastasize hematogenously in up to 20% of cases.
Regional lymph node metastasis is unusual
Histopathologic grade is predictive of metastasis, and resected tumor margins predict local recurrence.
Measurable or bulky (>5 cm in diameter) tumors generally have a poor response to chemotherapy and radiation therapy (RT).

Question 11

describe equine malignant melanoma

Answer 11

80% of grey horses over the age of 15 will develop at least one melanoma tumor during their lifetime
Can be fatal
There is no available effective chemotherapy for horses.
Tumor of the melanocytes, the cells that produce skin pigment.
Most common location: underside of the tail, the perineal and peri-anal regions, penis and sheath in males
Can also be found: ear margins, anywhere on the head, jugular region, new or on the parotid salivary gland
It is also possible that the melanomas can spread internally, most commonly to the serosal surfaces of the liver, spleen, and lungs
Can be hard or soft, and appear either solitary or in clusters
Start off under the skin until they surface. They can become ulcerated and/or infected

Question 12

How do melanoma’s develop

Answer 12

1- Melanomas develop slowly over years, and remain benign 10-20 years, without metastasis. Most common.
2- Benign melanomas that exist for months or years and suddenly develop malignant characteristics and spread rapidly externally and/or internally.
3- Melanomas are malignant from the start. Rare.

Question 13

where can malignant melanoma metastasis to

Answer 13

Metastasis: lymph nodes, liver, spleen, skeletal muscle, lungs, and surrounding or within blood vessels throughout the body

Question 14

Describe feline oral squamous cell carcinoma

Answer 14

Most common oral malignancy in the cat
Can originates from the jaw bones or the tongue
Owners may find a mass in their cat’s mouth which occurs mostly in the back of the mouth or under/on the tongue
It has an ability to grow invasively (locally), but does not tend to metastisize
Can be ulcerative or proliferative
No breed/sex predisposition, usually affects middle-aged cats

Question 15

what are the symptoms of the feline oral squamous cell carcinoma

Answer 15

mass that can be ulcerative
drooling
weight loss, 
halitosis
difficulty eating
bloody discharge from the mouth

Question 16

What are the environmental factors that contribute to oral SCC

Answer 16

Second Hand Smoke
flea collars
Diet

Question 17

How do you diagnose oral SCC

Answer 17

Often not diagnosed until the tumour is advanced
Oral examination
An ulcerated, red, locally invasive lesion is highly suggestive of an oral tumor
Loose teeth can suggest bone structure is affected
Bloodwork to check overall health
Radiographs
Can reveal invasion of underlying bone
Biopsy of abnormal tissue
Used to confirm the presence of SCC and help stage the tumor
Important to obtain a large sample since feline oral SCC are frequently infected, necrotic, or inflamed.

Question 18

Describe the treatment of feline oral SCC

Answer 18

Surgical removal is possible but can be difficult due to the aggressiveness and invasiveness that typically involves the bone. This means part of the jaw would need to be removed
Radiation therapy or chemotherapy alone is generally ineffective in the managing oral SCC.
The combination of the two can improve quality of life and overall survival time.

Pain medication can help reduce discomfort associated with the tumor.

Question 19

Describe the prognosis of feline oral SCC

Answer 19

Extremely poor
1 year survival rate is less than 10% even with combinations of radiation therapy and chemotherapy
Most cats are euthanized withing 1-3 months because they cannot eat or drink and poor quality of life

Question 20

What are the malignant oral tumors

Answer 20

squamous cell carcinoma
melanocyte tumor
fibrosarcoma

Question 21

What are the benign oral tumors

Answer 21

epulides

Question 22

How do you treat oral tumors

Answer 22

Surgery and RT are the most common treatments used for the local control of oral tumors.

Question 23

What are the symptom of oral melanoma in dogs

Answer 23

Halitosis
Drooling
Bleeding from the mouth
Change in food preference
Change in chewing habits
Decrease in appetite
Chronic coughing
Difficulty swallowing
Weight loss

Question 24

What causes canine oral melanoma

Answer 24

idiopathic

Question 25

How do yu diagnose canine oral melanoma

Answer 25

Physical exam: Blood tests, UA, X-rays, abdominal ultrasound, MRI, fluid biopsy Older dogs will have dark pigmented areas on the tongue, mouth and gums. Look for anything unusual in the mouth pigmented or non-pigmented fleshy masses. Metastasis: Head, neck, lymph nodes, liver, lungs, kidneys and sometimes bone tissue

Question 26

how do you treat canine oral melanoma

Answer 26

Removal of tumor: Sometimes hard to completely remove because it may spread to the bone in the mouth. Can return even if completely removed. Resistant to chemo. Radiation: Remission in 70% of patients. Reoccurrence and spread still possible. New vaccine restricted availability.

Question 27

what is the prognosis from canine oral melanoma

Answer 27

``` 5-7 months, but; Stage 1: 1 year Stage 2: 6 months Stage 3: 3 months Stage 4: 1 month ```

Question 28

describe nasopharyngeal polyps in cats

Answer 28

Nonneoplastic, inflammatory masses originating from either the middle ear or eustachian tube can extend into the external ear canal or nasopharynx Younger cats Idiopathic

Question 29

Describe the tumors of the liver

Answer 29

Primary tumors rare Prognosis variable Metastasis are frequent Nodular hyperplasia common diagnosis in older dogs benign and probably does not represent a preneoplastic lesion

Question 30

describe feline intestinal lymphoma

Answer 30

Can present as: a purely intestinal infiltration or a combination of intestinal, mesenteric lymph nodes and liver involvement Tumors can be solitary but more commonly diffuse throughout the intestines Common Older cats, mostly small intestine Often preceded by IBD

Question 31

Describe perianal adenomas in animals

Answer 31

Benign sex-hormone dependent (spayed female, intact male)

Question 32

Describe apocrine gland adenocarcinoma

Answer 32

Tiny primary tumor (often pea-size) About 50% metastasis at diagnosis Hypercalcemia (PU/PD)

Question 33

Describe canine chondrosarcoma

Answer 33

Chondrosarcoma is a form bone cancer in dogs The cancer starts in the cartilage and connective tissue found in joints, and/or ribs and nose. It can cause bones to fracture easily as the tumour invades the bones. It is mostly common in older dogs

Question 34

How do you treat canine chondrosarcoma

Answer 34

Better prognosis if caught early and treated aggressively. Amputation of the affected limb if no metastasis has occurred. Radiation therapy if located in the nose. Removal of the affected rib and portion of the lung if tumour is on rib followed by chemotherapy. Inoperable tumours are treated with radiotherapy to try to prolong the life span. Surgery is the only known affective treatment.

Question 35

How do you diagnose canine chondrosarcoma

Answer 35

``` Xrays CBC Lymph biopsy Biopsy of tumour CT scan ```

Question 36

describe canine osteosarcoma

Answer 36

``` Most common bone tumor found in dogs 5% of all canine tumors Malignant Can effect any breed Most common in large or giant breeds. Middle aged or elderly ```

Question 37

What are the primary osteosarcoma tumor sites

Answer 37

``` Bordering the scapula Tarsus Carpus Stifle Commonly near growth plates ```

Question 38

Where does canine osteosarcoma metastasize to

Answer 38

Lungs other bones lymph nodes

Question 39

What are the risk factors associated with canine osteosarcoma

Answer 39

Slightly more in females than males | Higher in castrated males and spayed females (compared to intact)

Question 40

What are the symptoms of canine osteosarcoma

Answer 40

``` Lameness Periosteal inflammation Microfractures Pathologic factors Swelling ```

Question 41

how do you diagnose canine osteosarcoma

Answer 41

Orthopedic, neurologic and physical examination X-rays (if lesion is in question – do a biopsy) Biopsy through aspiration Bone scan

Question 42

how do you treat canine osteosarcoma

Answer 42

Aggressive treatment plan Radiation therapy – palliative care not curative Curative options include a combination of surgery, radiation therapy and chemotherapy Standard treatment is amputation

Question 43

what is the prognosis for osteosarcoma

Answer 43

Very good prognosis with amputation: resolves 100% of the pain

Question 44

What is the aetiology and pathogenesis of insulinomas

Answer 44

Insulinomas are tumors of the pancreatic β cells (type of islet cell) which produce insulin These tumors cause increased insulin production which result in hypoglycemia The tumors respond to normal provocative stimuli that encourage a rise in insulin, but fail to respond to negative feedback when the insulin levels are too high Insulinomas are very common in middle-aged and older ferrets ( greater than 3 years of age)

Question 45

What are the clinical signs of insulinomas

Answer 45

Hypoglycemia will result in neurological signs such as mental dullness, sluggishness, lethargy, ataxia, seizures and coma Prolonged, severe hypoglycemia can result in cerebral hypoxia and cerebral lesions Other possible symptoms are nausea (which can cause the ferret to paw at its mouth), depression, hypersalivation, staggering, tachycardia, hypothermia, tremors, muscle fasciculations, nervousness and irritability Owners may report that the ferret tends to sleep more frequently, be difficult to wake up, or stops in its tracks with a dazed appearance It is important to note that these symptoms can come and go as blood sugar levels rise and drop

Question 46

how do you diagnose insulinomas

Answer 46

One of the most common illnesses diagnosed in ferrets Will be diagnosed using clinical signs, history, physical exam, blood glucose levels and insulin levels

Question 47

How do you treat ferret insulinoma

Answer 47

Surgery to remove the tumors (the tumors often grow back so several surgeries will likely be required) Medication to manage insulin and glucagon levels (the dose will need to be increased as the illness progresses) Diet is another huge component to managing this disease. All ferrets should be fed a high-protein ferret food, but this is especially important in sick ferrets

Question 48

what is the prognosis for ferret insulinomas

Answer 48

Most insulinomas are eventually fatal This is either because of hypoglycemic induced complications or because the tumors have spread to other organs All that can be done is attempt to maintain a good quality of life for the ferret for as long as possible

Question 49

describe pituitary adenoma

Answer 49

Common pituitary neoplasia of older dogs Most common cause of cushing in horses. Pituitary tumors account for approximately 15% of intracranial tumors Frequently associated with either: -hyperadronocorticism
 - Diabetes Insipitus

Question 50

What are the clinical signs of pituitary adenoma

Answer 50

``` Non-neurological: weight loss, PU/PD, lethargy
 Neurological signs: cranial compression is rare but pressure on the optic chiasma may cause ocular changes ```

Question 51

how do you diagnose pituitary adenoma

Answer 51

imagining with CT or MRI may be difficult, but a definitive diagnosis is usually done with a intraoperative or postmortem biopsy Differential diagnosis: lymphoma, hypothalamic-pituitary trauma, dorsally expanding cysts, congenital malformations, inflammatory granuloma, etc.

Question 52

how do you treat pituitary adenoma

Answer 52

corrective hormonal therapy or hypophysectomy (removal of the pituitary gland)

Question 53

what is the prognosis for pituitary adenoma

Answer 53

Prognosis depends upon the type and size of the tumour. The prognosis for a pituitary tumor (if the client is willing to do treatments) is usually fairly good as the treatments are quite effective. In serious unnoticed cases The entire hypothalamus may become compressed and replaced by the tumor.

Question 54

How can you determine whether cushings disease is caused by the pituitary or the adrenal adenoma

Answer 54

If there is no change in Cortisol levels being released by the adrenal gland, then it is an Adrenal Adenoma. If there is suppression of the adrenal gland, then the Cushing’s is being caused by a Pituitary Adenoma.

Question 55

Describe pheochromocytoma

Answer 55

``` Adrenal gland tumor Older dogs Secretes catecholamines (episodic) episodic collapse, panting, anxiety, restlessness, exercise intolerance Malignant (40% metastasize) Good prognosis is no metastasis ```

Question 56

Describe thyroid gland adenomas in dogs

Answer 56

``` Often benign adenoma found at necropsy Malignant: If clinical signs of hyperthyroidism (most non-functional) Older dogs Frequent metastasis ```

Question 57

Describe hyperthyroidism

Answer 57

Multinodular adenomatous hyperplasia | Carcinoma rare

Question 58

describe insulinoma

Answer 58

Pancreatic Beta-Cell Tumors Hallmark of insulinoma normal or elevated blood insulin concentration in the presence of low blood glucose levels Often malignant 50% metastasis Medium and large breed dogs, older

Question 59

What are the clinical signs of insulinoma

Answer 59

weakness, ataxia, collapse, disorientation, behavioral changes, and seizures

Question 60

How do you treat insulinoma

Answer 60

Medical and surgical treatment | prognosis for dogs with insulinomas is good in the short term but guarded to poor in the long term

Question 61

What is a gastrinoma

Answer 61

``` Often pancreatic, secretes gastrin Gastric acid hypersecretion Middle-aged dogs and older cats Non-specific clinical signs vomiting and weight loss melena, abdominal pain, anorexia, hematemesis, hematochezia, and diarrhea Often metastasis at diagnosis ```

Question 62

What is a transitional cell carcinoma

Answer 62

Fairly common malignant tumor Located in the trigone region of the bladder 15% metastasis at diagnosis 30% of dogs have abnormal cells in urine

Question 63

What are the signs of the transitional cell carcinoma

Answer 63

hematuria, dysuria, pollakiuria | less commonly: lameness caused by bone metastasis

Question 64

What is canine lymphoma

Answer 64

Is a common type of cancer in dogs. Unregulated growth of malignant lymphocytes that often affects; lymph nodes, bone marrow, liver, and spleen. Can also be seen in the eyes, skin, and gastrointestinal tract. It can be small cell lymphoma; progresses very slowly and is difficult to treat. There is also large cell lymphoma; progresses quickly but responds very well to chemotherapy.

Question 65

What are the 5 stages of canine lymphoma

Answer 65

Stage I: Ailment restricted to a single lymph node. Stage II: Regional lymphadenopathy (restricted to one side of diaphragm). Stage III: Generalized lymphadenopathy (enlargement of lymph nodes) Stage IV: Enlargement of the liver and spleen or hepatosplenomegaly (with or without lymphadenopathy). Stage V: Bone marrow, CNS (Central Nervous System), or involvement of other extranodal sites.

Question 66

what are the symptoms of canine lymphoma

Answer 66

Firm, enlarged, non-painful lymph nodes. Other common symptoms include loss of appetite, lethargy, weight loss, swelling of the face or legs (edema), and occasionally increased thirst and urination.

Question 67

how do we diagnose canine lymphoma

Answer 67

Best way is to perform a biopsy; you are able to differentiate between T and B cells with special stain because they respond differently to treatment.

Question 68

how do we treat canine lymphoma

Answer 68

Most effective therapy is chemotherapy. In some situations, surgery or radiation therapy may also be recommended.

Question 69

what is the prognosis for canine lymphoma

Answer 69

Depends on what type of lymphoma the dog has and the type of chemotherapy. The average for multicentric lymphoma is 9-13 months.

Question 70

describe leukemia

Answer 70

``` Many different types of leukemia Myeloid: white blood cells Erythroid: RBC All from bone marrow Can be acute or chronic Acute: high cell counts, immature cells Chronic: moderate cell counts, mature cells Bone marrow examination important ```

Question 71

what are the signs of multiple myeloma

Answer 71

Bleeding (nose, gums) Lameness PU/PD Elevated globulins

Question 72

describe the prognosis of multiple myeloma

Answer 72

Dog: good for initial control of tumor and a return to good quality of life (median 540 days) Cats: 4 months

Question 73

describe plasmacytoma

Answer 73

Local & Benign form of plasma cell tumor Older dogs Limb, head, lips Conservative surgical excision

Question 74

describeb mast cell tumors in dogs

Answer 74

Mast cells are found in the connective tissues mostly in the vessels and nerves that are located close to the external surfaces. Boxers, bulldogs, pugs, and Boston terriers appear to be more susceptible to mast cell tumors than other breeds. Dogs affected with a mast cell tumor are around 8 years old but studies show that there has been cases of mast cell tumor seen in less than 1 year old dogs

Question 75

where is the primary tumor site for mastocytoma

Answer 75

skin, nose, mouth, lungs

Question 76

describe the metastasis of mast cells

Answer 76

Depending on the stages, stage 2 will metastasize into surrounding lymph nodes and stage 4 will metastasize to other organs.

Question 77

How do you diagnose mast cell tumors

Answer 77

``` Fine needle aspiration Cytology Biopsy surgical removal radiation therapy (if metastasis occurs) ```

Question 78

What is the prognosis for a mast cell tumor

Answer 78

The prognosis will depend on the growth of the tumor If the tumor grows more than 1 cm per week, the animal only has 25% chances of surviving more than 30 weeks If the tumor is located at one specific area and does not grow rapidly for several months, it is known to be benign

Question 79

What are some complications associated with mast cell tumor

Answer 79

In some cases, you might noticed an enlargement of the lymph nodes located around the area of the tumor Some masses can be inflammed and itchy due to high level of histamines in the actual tumor
 Enlarged liver and enlarged spleen are characteristic of wide-spread mast cell cancer

Question 80

What is a thymoma

Answer 80

Older (9-10 yo) dogs (and cats) Neoplasms of thymic epithelial cells Benign vs malignant based on surgery

Question 81

What are the clinical signs of a thymoma

Answer 81

Lethargy, coughing, tachypnea, and dyspnea

Question 82

What can a thymoma cause in some animals

Answer 82

myasthenia gravis (in 40% of dogs)

Question 83

What is myasthenia gravis

Answer 83

Autoimmune disease of the neuromuscular junction causing muscular weakness and excessive fatiguability Megaoesophagus (regurgitation) 3% of dogs with MG have a cranial mediastinal mass

Question 84

What are histiocytic diseases

Answer 84

Neoplasia of macrophage (and related cells)

Question 85

What is a histiocytoma

Answer 85

Nodular skin tumor of young dogs (head/neck) Very common Benign, regresses spontaneously

Question 86

What is a histolytic sarcoma

Answer 86

Bernese Mountain dogs, rottweilers, retrievers Spleen, liver, lungs Very poor prognosis

Question 87

Describe mammary tumors in dogs

Answer 87

``` Common in intact females Heterogenous group of tumors (10+) More research needed Impacts the course of action/treatment Metastasis common ```

Question 88

Describe mammary tumors in cats

Answer 88

Siamese cat younger, overrepresented Intact cats The vast majority of feline mammary tumors are malignant (85% to 95%) with an aggressive biologic behavior, lymphatic invasion and lymph node metastasis are more common at the time of initial diagnosis than in dogs Needs aggressive surgery

Question 89

Describe a canine prostate tumor

Answer 89

Older dogs, intact and neutered (slightly more) At the time of diagnosis Most tumor are locally invasive High propensity for regional and distant metastasis Bones (lumbar vertebra and pelvis)

Question 90

what are the signs of a canine prostate tumor

Answer 90

hematuria, dysuria, stranguria, | dyschezia, tenesmus