Oncology - GI tumors

Question 1

what percentage of tumors do oral tumors account for in dogs?

Answer 1

5%

Question 2

what is the presenting complaints we usually see with oral tumors?

Answer 2

visible mass with oral bleeding, difficulty eating or halitosis

Question 3

what are the 3 big differential diagnoses for oral tumors?

Answer 3

1. melanoma
2. SCC
3. fibrosarcoma

Question 4

what are the 2 big differential diagnoses for oral tumors?

Answer 4

1. SCC

2. fibrosarcoma

Question 5

how do we diagnose oral tumors?

Answer 5

• cytology not effective
• need incisional biopsy for tissue dx
  
  • NEVER biopsy an oral mass through the lip
• dental radiographs or CT
• LN staging

Question 6

true or false.

malignant melanoma is always pigmented black.

Answer 6

false, non-pigmented variant - amelanotic melanoma

Question 7

is melanoma highly malignant?

Answer 7

yes! mets in 80% of cases, thorough staging is required

Question 8

what are the risk factors for cats getting SCC?

Answer 8

• flea collar usage
• smoke exposure
• excessive canned food

Question 9

what site does SCC prefer in cats?

Answer 9

sublingual site

Question 10

who do we commonly see fibrosarcoma in ?

Answer 10

large breed middle aged (7-8 yrs) like goldens and labs

Question 11

true or false.

fibrosarcoma is very invasive locally and often looks metastatic

Answer 11

FALSE, often looks benign

Question 12

what should you do if you think you have fibrosarcoma but the biopsy comes back as fibroma?

Answer 12

don’t believe it

Question 13

where do odontogenic tumors arise from?

Answer 13

periodontal ligament

Question 14

are odontogenic tumors malignant or benign?

Answer 14

benign but can be locally invasive

Question 15

what is the gold standard of treatment for oral tumors?

Answer 15

aggressive surgical excision with the exception of peripheral odotogenic fibroma

Question 16

true or false.

oral tumors almost always have bone involvement

Answer 16

true

Question 17

true or false.

a more rostral mass is harder to excise and has a worse prognosis.

Answer 17

false! it’s easier to excise giving it a better prognosis

Question 18

is radiation therapy effective for oral tumor management ?

Answer 18

yes

Question 19

are esophageal tumors common in cats or dogs?

Answer 19

no, rare, may never see it during career

Question 20

what is a cause of esophageal tumors?

Answer 20

spirocerca lupi infection causing sarcoma

Question 21

whats the most common differential for esophageal tumor?

Answer 21

SCC

others - leiomyosarcoma, fibrosarcoma

Question 22

how do we diagnose esophageal tumors?

Answer 22

• imaging - radiographs or esophagram

- esophagoscopy - can obtain biopsies this way

Question 23

how do we treat esophageal tumors?

Answer 23

• surgery is the preferred treatment but is challenging
• radiation therapy but limited due to side effects of surrounding areas
• palliative care

Question 24

what is the prognosis for esophageal tumors?

Answer 24

very poor

Question 25

what breeds are genetically predisposed to gastric tumors ?

Answer 25

BELGIAN shepherds and chows

Question 26

true or false. | most dogs are asymptomatic until tumor becomes large enough to effect outflow

Answer 26

true

Question 27

where does gastric adenocarcinoma have a preference for?

Answer 27

pyloric antrum/lesser curvature

Question 28

does gastric adenocarcinoma have a high metastatic rate?

Answer 28

yes. 74%

Question 29

what are 2 big differentials with gastric tumors in dogs?

Answer 29

adenocarcinoma (70-80% of GI neoplasms) and leimyosarcoma

Question 30

what is the 1 big differential with gastric tumors in cats?

Answer 30

lymphoma

Question 31

how do we work up a gastric tumor ?

Answer 31

- endoscopy - preferred and can get biopsies - minimum database - abdominal US - US guided FNA/cytology - positive contrast gastrogram

Question 32

what is the treatment for for gastric tumors?

Answer 32

surgical excision

Question 33

whats the prognosis of gastric adenocarcinoma ?

Answer 33

poor prognosis, majority dead within 6 months | - if no mets and able to resect, lengthy survival possible

Question 34

can leiomyoma be cured with surgery?

Answer 34

yes

Question 35

which is more common in dogs, large intestine or small intestine tumors?

Answer 35

large intestine

Question 36

which breeds are predisposed to intestinal tumors?

Answer 36

GERMAN shepherd and collies

Question 37

which is more common in cats, large intestine or small intestine tumors?

Answer 37

small intestine

Question 38

when doing endoscopic biopsy what is a common misdiagnosis ?

Answer 38

it is common to misdiagnose LSA with IBD in cats

Question 39

how should we diagnose intestinal tumors?

Answer 39

US guided FNA

Question 40

what are the big 3 differentials for intestinal tumors in dogs?

Answer 40

1. LSA 2. ACA 3. Leiomyosarcoma

Question 41

what are the big 3 differentials for intestinal tumors in cats ?

Answer 41

1. LSA 2. ACA 3. MCT

Question 42

when treating intestinal tumors should we do surgical excision with cases of LSA ?

Answer 42

NO, this is the exception

Question 43

what is the majority cell line in dogs with intestinal LSA?

Answer 43

T cell origin

Question 44

what is the majority cell line in cats with intestinal LSA?

Answer 44

B cell origin

Question 45

true or false. | In dogs, intestinal MCT have 100% rate of metastasis

Answer 45

true, very bad disease to have, MST is 16 days

Question 46

where do gastrointestinal stromal tumors have an affinity for ?

Answer 46

the cecum

Question 47

how can we diagnose gastrointestinal stromal tumors?

Answer 47

they express c-kit so can do immunohistochemistry for that