Tumors Of The GI Tract

Question 1

What are other malignancies are observed with the “Big 3” oral tumors for dogs?

Answer 1

OSA*(mandible/maxilla)
CSA
HSA
LSA
MCT

Question 2

What type of biopsy do we perform for oral tumor diagnosis?

Answer 2

Incisional —>”Shave” biopsy if proliferative: - Blade 1cm piece then tamponade and it will stop bleeding in short order (NO suture!)

If NOT proliferative, do NOT compromise 2nd surgery; Also, it will bleed/too reactive…

Question 3

In order to see (on radiographs) evidence of bone lysis, you have to have what per cent of the cortex destroyed?

Answer 3

At least 40% of the cortex destroyed before you can SEE evidence of bone lysis… This is why it’s not a great help in work up and staging

Question 4

What are some important considerations in managing malignant melanoma?

Answer 4

Mets in 80% of cases
Thorough staging required:
- abdominal US
- full body CT if performing for locoregional assessment for Sx
*surgery results in local control in 75%of cases —> biggest point of failure: systemic Mets*

Question 5

Signalment for canine fibrosarcoma?

Answer 5

Younger (7-8y)
Large breed {Goldens and labs}

Question 6

What is a “histologically low-grade but biologically high-grade variant” of Fibrosarcoma (usu. in Goldens<2y)?

Answer 6

Aka “hi-lo’s” Seemingly benign on histopathology, but behave aggressive biologically — can come back as “fibroma” from lab - dont believe it!

Question 7

Risk factors for SCC in cats?

Answer 7

Flea collar usage (3.5x)

Smoke exposure (2x)

Excessive canned food (esp. tuna)

Question 8

Preferred site for oral SCC in cats?

Answer 8

Sublingual site

Question 9

What can odontogenic tumors (fibromas) be easily confused with?

Answer 9

Gingival hyperplasia

Question 10

The rostral mandible is a predisposed site for which odontogenic tumor, esp. in Shetland and OE sheep dogs?

Answer 10

Acanthomatous ameloblastomas

Question 11

What is the margin procurement for oral tumor malignancies?

Answer 11

2cm

*1cm for acanthomatous ameloblastoma

Question 12

How is the site location of an oral tumor prognostic?

Answer 12

More rostral=easier to remove= better prognosis

Question 13

What do cats NEED to go on for sublingual SCC?

Answer 13

Piroxicam (NSAID) —> it can double ST by giving ALONE…(3months vs 6months)

Mech: COX-2 is overexpressed in these carcinomas and the tumors use this to recruit new blood vessels and proliferate

Question 14

What is the most common type of esophageal tumor?

Answer 14

SCC

Question 15

Signalment for Esophageal SCC in a cat?

Answer 15

Female, Middle esophagus-just caudal to thoracic inlet

Question 16

How do we treat an esophageal tumor secondary to Spirocerca lupi granuloma?

Answer 16

Doramectin will resolve lesion!

Question 17

What is the genetic predisposition for gastric tumors?

Answer 17

Belgian shepherds Chows Beagles

Question 18

What are the “Big 2” gastric tumors in dogs?

Answer 18

Adenocarcinoma (70-80% of gastric neoplasms)
Leiomyosarcoma

Question 19

Preferred site of gastric adenocarcinomas?

Answer 19

Pyloric antrum/lesser curvature of the stomach VERY infiltrative,
high met rate (74%)

Question 20

What’s the gold standard for work up and staging of gastric tumors?

Answer 20

Endoscopy: Allows for biopsy procurement (of course…)

Question 21

What type of gastric tumor prefers the cardia location?

Answer 21

Leiomyomas

Question 22

About how long can a dog live for following surgical resection of a leiomyosarcoma?

Answer 22

8 months

Question 23

Predilection site for GISTs?

Answer 23

Cecum (often get large and rupture, causing septic peritonitis)

Question 24

In general, small intestinal tumors are more common than large intestinal in _____, but large intestinal tumors are more common in ____.

Answer 24

cats;
dogs

Question 25

What is the most common site for intestinal lymphoma tumors in cats?

Answer 25

Ileum!

which is NOT fully accessible by colon-endo-scope so you could miss it…

Question 26

How should we treat oral malignant melanoma (besides surgery)?

Answer 26

Radiation Therapy:
Hypofractionated regimen where we gives larger doses over shorter periods of time , so usually 4-6 doses total instead of conventional radiation like 5 days on, 2 days off for a month…

Question 27

T or F:
Being female is a negative prognostic indicator for canine adenocarcinoma.

Answer 27

True.
racist…