common neoplasms

Question 1

papillomas

Answer 1

• common in young animals
• spontaneously regressed
• seen in head, mouth, genital area, esophagus, forestomachs

**areas of stratified squamous epithelium

Question 2

Is squamous cell carcinoma fast-growing or slow-growing?

Answer 2

slow-growing

• common in older horses
• *metastasis is uncommon

Question 3

What is a major rule-out for SCC in horses?

Answer 3

cutaneous habronemiasis of the prepuce and penis

Question 4

sebaceous adenoma/epithelioma

Answer 4

• nodular sebaceous hyperplasia
• eptheliomas have low-grade malignancy
• adenomas are benign

**very common in older dogs; UNCOMMON in cats

Question 5

what are the common locations for sebaceous adenoma/epithelioma in the dog and the cat?

Answer 5

Dog: often on the head

Cat: head, back, and tail

Question 6

What are 5 types of follicular neoplasms?

Answer 6

1. infundibular keratinizing acanthoma
2. trichoblastoma
3. trichoepithelioma
4. pilomatricoma
5. basal cell tumor

Question 7

Are follicular neoplasms benign or malignant?

Answer 7

benign

Question 8

What are common sites of follicular neoplasms?

Answer 8

• head
• neck
• back
• thorax
• tail

Question 9

perianal adenoma/carcinoma

Answer 9

-pale brown and multilobulated on cut surface

ONLY IN DOGS

Question 10

perianal adenoma/carcinoma: which are more common: malignant vs benign

Answer 10

benign tumors are MORE common than malignant tumors

benign: adenoma
malignant: carcinoma

Question 11

anal sac apocrine gland adenocarcinoma

Answer 11

VENTROLATERAL ASPECT OF ANUS

• mets to lung, lymph nodes, and other organs
• poor prognosis

Question 12

mesenchymal neoplasia

Answer 12

-arisses from non-neural, non-epithelial tissues (i.e.: connective tissue)

Question 13

Where in the body can we see mesenchymal neoplasia?

Answer 13

1. stroma: fibroblasts, chondrocytes, osteoblasts
2. bone marrow
3. lymphoid tissues

Question 14

Name 6 types of round cell tumors

Answer 14

1. plasma cell tumor
2. canine cutaneous histiocytoma
3. mast cell tumor
4. melanoma/melanocytoma
5. lymphoma
6. transmissible venereal tumor

Question 15

canine cutaneous histiocytoma

Answer 15

“red-button tumor”

• benign, very common
• common in young dogs

Preferred sites: head, pinna, limbs

Question 16

what are the 2 most common dog breeds affected by mast cell tumors?

Answer 16

1. Boxer

2. Boston terrier

Question 17

occasionally, — occurs secondary to histamine release rom neoplastic mast cells

Answer 17

GI ulceration

Question 18

Are cutaneous mast cell tumors malignant in dogs?

Answer 18

Yes (grade based on microscopic appearance)

• single or multicentric
• erythematous, alopecic, edematous

Question 19

Are cutaneous mast cell tumors malignant in cats?

Answer 19

Benign

• superficial, well-demarcated –> usually cured by complete excision
• *multicentric

Question 20

Are cutaneous mast cell tumors malignant in horses?

Answer 20

Benign; spontaneously regress

• *no grading system
• *may contain numerous eosinophils

Question 21

What is a common cutaneous site for mast cell tumors in dogs?

Answer 21

the scrotum

Question 22

What cells do neoplastic lymphocytes arise from?

Answer 22

B cells
T cells
NK cells

Question 23

Malignant lymphoma is associated with retrovirus in what species?

Answer 23

1. cats (FeLV)

2. cattle (BLV)

Question 24

What are the common sites for lymphoma in cats?

EXAM QUESTION

Answer 24

1. intestinal form
2. multicentric (generalized) form
3. cranial mediastinal (thymic) form

Question 25

What are the common sites for lymphoma in cattle?

Answer 25

HAULS 1. right atrium 2. abomasum 3. uterus 4. lymph nodes 5. spinal canal

Question 26

Where does melanoma originate from?

Answer 26

neural crest cells

Question 27

Where do we see melanoma in dogs? Are they metastatic?

Answer 27

1. haired skin: malignant are slow to metastasize | 2. oral cavity (90% malignant)

Question 28

vaccine-associated sarcomas

Answer 28

-associated with rabies and FeLV Dx: FNA or biopsy -sarcomas are aggressive and recur faster and more aggressively after removal; slow to metastasize

Question 29

What are some differential diagnoses for equine sarcoids?

Answer 29

1. cutaneous habronemiasis 2. chronic granulation tissue 3. fibrosarcoma or neurofibrosarcoma

Question 30

Equine sarcoids

Answer 30

associated with bovine fibropapilloma virus - invasive, may recur - no metastasis

Question 31

Equine sarcoids are difficult to see in many samples because ---

Answer 31

cutaneous ulceration is common

Question 32

What are common locations for equine sarcoid?

Answer 32

mucocutaneous junction - mouth - eyes

Question 33

What are the three types of testicular tumors? Which is the most common?

Answer 33

1. interstitial cell tumor (MOST COMMON) 2. seminoma 3. sertoli cell tumor

Question 34

Are most testicular tumors benign or malignant? Age range??

Answer 34

benign (most common in older dogs)

Question 35

What fraction of sertoli cell tumors produce estrogen?

Answer 35

1/3

Question 36

What clinical signs would you see with estrogen producing sertoli cell tumors?

Answer 36

1. gynecomastia 2. alopecia 3. myelotoxicity 4. squamous metaplasia of the prostate

Question 37

Which two breeds do we commonly see HSA in?

Answer 37

1. Goldens | 2. German Shepherds

Question 38

What are 3 common sites for HSA?

Answer 38

1. spleen 2. right atrium 3. skin (dermal or subcutaneous)

Question 39

Do superficial cutaneous HSA have a good prognosis?

Answer 39

yes (test question)

Question 40

What are some consequences we see with HSA?

Answer 40

1. metastasis to lungs 2. hemopericardium 3. hemoperitoneum

Question 41

When do we see cutaneous hemangiosarcomas in dogs?

Answer 41

UV exposure in light haired areas