Tumors Of The GI Tract Flashcards
What are other malignancies are observed with the “Big 3” oral tumors for dogs?
OSA*(mandible/maxilla)
CSA
HSA
LSA
MCT
What type of biopsy do we perform for oral tumor diagnosis?
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…
In order to see (on radiographs) evidence of bone lysis, you have to have what per cent of the cortex destroyed?
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
What are some important considerations in managing malignant melanoma?
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*
Signalment for canine fibrosarcoma?
Younger (7-8y)
Large breed {Goldens and labs}
What is a “histologically low-grade but biologically high-grade variant” of Fibrosarcoma (usu. in Goldens<2y)?
Aka “hi-lo’s” Seemingly benign on histopathology, but behave aggressive biologically — can come back as “fibroma” from lab - dont believe it!
Risk factors for SCC in cats?
Flea collar usage (3.5x)
Smoke exposure (2x)
Excessive canned food (esp. tuna)
Preferred site for oral SCC in cats?
Sublingual site
What can odontogenic tumors (fibromas) be easily confused with?
Gingival hyperplasia
The rostral mandible is a predisposed site for which odontogenic tumor, esp. in Shetland and OE sheep dogs?
Acanthomatous ameloblastomas
What is the margin procurement for oral tumor malignancies?
2cm
*1cm for acanthomatous ameloblastoma
How is the site location of an oral tumor prognostic?
More rostral=easier to remove= better prognosis
What do cats NEED to go on for sublingual SCC?
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
What is the most common type of esophageal tumor?
SCC
Signalment for Esophageal SCC in a cat?
Female, Middle esophagus-just caudal to thoracic inlet
How do we treat an esophageal tumor secondary to Spirocerca lupi granuloma?
Doramectin will resolve lesion!
What is the genetic predisposition for gastric tumors?
Belgian shepherds Chows Beagles
What are the “Big 2” gastric tumors in dogs?
Adenocarcinoma (70-80% of gastric neoplasms)
Leiomyosarcoma
Preferred site of gastric adenocarcinomas?
Pyloric antrum/lesser curvature of the stomach VERY infiltrative,
high met rate (74%)
What’s the gold standard for work up and staging of gastric tumors?
Endoscopy: Allows for biopsy procurement (of course…)
What type of gastric tumor prefers the cardia location?
Leiomyomas
About how long can a dog live for following surgical resection of a leiomyosarcoma?
8 months
Predilection site for GISTs?
Cecum (often get large and rupture, causing septic peritonitis)
In general, small intestinal tumors are more common than large intestinal in _____, but large intestinal tumors are more common in ____.
cats;
dogs
