Sarcoma And Tumors Of Abdominal Cavity

Question 1

What are soft tissue sarcomas?

Answer 1

Locally invasive with low to moderate risk of mets

Most are solitary

Many variants: fibrous, adipose, skeletal muscle, vascular/lymphatic, peripheral nerve, synovial, smooth muscle

Question 2

What are the important common features of STS?

Answer 2

Pseudo-encapsulated soft to firm masses with poorly defined margins (infiltrative)

Local recurrence after conservative excision is common

Hematogenous route of mets

Regional LN met uncommon (except synovial cell)

Grade is predictive of local recurrence

Bulky tumors do not respond to chemo or RT

Question 3

What workup/staging do you do for soft tissue sarcomas?

Answer 3

FNA—> rule out lipoma/seroma/inflammation/abscess

Sarcoma —> is it important to know grade for therapy?

Incisional biopsy (tru-cut vs wedge —> not usually punch since they are often hypodermal)

Thoracic radiographs for pulmonary mets

Regional imaging - abdominal us for presurgical staging is generally not indicated for most STS

Question 4

What are negative prognostic indicators for soft tissue sarcomas?

Answer 4

Large tumor size
Incomplete surgery margins
High histologic tumor grade = higher met rate and more locally invasive

Question 5

What is the recurrence rate of soft tissue sarcoma that is not completely resected?

Answer 5

28%

— recurrent STS are more difficult to control than the primary tumors

Question 6

What is a feline injection site sarcoma ??

Answer 6

Sarcoma are histologically and biologically more aggressive

Question 7

What causes an injection site sarcoma?

Answer 7

Aluminum adjuvant in vaccine was contributing to massive inflammatory rxn —> leads to uncontrolled fibroblast and myofibroblast proliferation and eventual tumor formation

Question 8

For feline injection site sarcomas, what is the time between vaccination to tumor development

Answer 8

Anywhere from 4 weeks to 10 yrs

Question 9

Workup for Feline ISS?

Answer 9

Cytology —> give Dx of sarcoma
Can to incisional biopsy to confirm type of sarcoma

DO NOT do excisional biopsy

Question 10

What is the treatment for Feline ISS?

Answer 10

Surgical excision with 5cm radial margins and 2 muscle planes deep
- including body wall, soft tissue, or bone

Question 11

What is the recurrence rate of feline ISS?

Answer 11

14%

Question 12

T/F: liver tumors in dogs and cats are most commonly metastatic because the liver is a receptacle for blood supply form GI tract, spleen, and pancrease

Answer 12

False

Dogs — met tumors 2.5x more common than primary tumors

Cats — primary tumors more common

Question 13

Liver tumors are more commonly (malignant/benign) in dogs and are vice versa in cats

Answer 13

Malignant

Question 14

What are the 4 classifications of liver tumors?

Answer 14

Hepatocellular
Bile duct
Neuroendocrine
Mesenchymal

• prognosis of any tumor determined greatly by histology of the tumor

Question 15

Primary hepatobiliary tumors can have what morphological?

Answer 15

Massive - large, solitary mass on a single liver lobe

Nodular - multifocal varying sizes, on one or several lobes

Diffuse - multifocal to coalescing nodules involving ALL liver lobes or diffused effacement of parenchyma

Question 16

Most hepatocellular tumors have what morphology?

Answer 16

Massive

Question 17

Common signalment of hepatobiliary tumors?

Answer 17

Disease of older animals

HCC and sarcomas occur slightly more frequently in male dog with slight female predisposition in bile duct tumors

Question 18

Common presenting complaint its hepatobiliary tumors?

Answer 18

Most are asymptomatic - most found while chasing

Clinical signs are variable/ non-specific = anorexia, wt loss, PU/PD, ascities

• icterus seen with biliary or diffuse neuroendocrine tumors
• seizure rare but can be caused by paraneopalsic hypoglycemia

Question 19

What is the most common primary liver tumor in dogs?

Answer 19

Hepatocellular carcinoma

Question 20

What is the most common primary liver tumor in cats

Answer 20

Hepatocellular adenoma

Question 21

How much liver can you surgically remove?

Answer 21

Liver is capable of removing form 65-75% loss of total mass = remaining volume can hypertrophy to original size within 6 week

Question 22

What is the mechanism of liver regeneration ?

Answer 22

Quiescent hepatocytes “primed” or simulated to grow

Continued growth mediated by growth factors (hepatocyte GF and TGFa)

Question 23

What is the complication rate to surgical excision of liver tumors>?

Answer 23

29% complication rate with 5% operative mortality

Question 24

T/F: local recurrence often develops in liver tumors if there are incomplete margins

Answer 24

False

Local recurrence did not occur inn tumors even with incomplete margins

Question 25

What are the two types of bile duct neoplasias?

Answer 25

Bile duct adenoma —> biliary or hepatobiliary cystadenoma

Bile duct carcinoma

Question 26

What is the most common liver tumor of cats repressing more than 50% of all feline hepatobiliary tumors

Answer 26

Hepatobiliary cystadenoma

Question 27

The most common malignant hepatobiliary tumor in a cat is ______________ and in a dog is __________

Answer 27

Bile duct carcinoma; hepatocellular carcinoma

Question 28

T/F: there have been long-term survival times reported in cats with hepatobiliary cystadenoma when treated with benign neglect

Answer 28

True

• remote possibility of malignant transformation should be discussed with owners

Question 29

T/F: hepatobiliary cystadenomas are most commonly incidental findings

Answer 29

True

Question 30

What is a risk factor for bile duct carcinoma in cats and dogs?

Answer 30

Trematode infestation

Question 31

Are bile duct carcinomas usually non- aggressive or aggressive?

Answer 31

Aggressive

Cats = carcinomatosis (diffuse intraperitoneal mets)

Question 32

T/F: chemotherapy and RT are good treatment options for bile duct carcinomas

Answer 32

False
-not effective

Surgical resection warranted, but survival times are poor