Neoplasms of the Liver

Question 1

In which species is primary hepatic tumour more common, cat or dog?

Answer 1

Cats!
Metastatic tumour is 3x more frequent than primary hepatic tumour in the dog

Question 2

Which species is more likely to have a benign hepatic tumour?

Answer 2

Cats! – if malignant, tend to be found at a younger age than benign ones
Dogs tend to get malignant hepatic tumours

Question 3

What are the 4 general tissues types for primary hepatic tumours?

Answer 3

1. hepatocellular
2. bile duct
3. neuroendocrine
4. mesenchymal

Question 4

What’s the most common primary hepatic tumour in the dog?

Answer 4

hepatocellular adenoma/ carcinoma

Question 5

What’s the most common primary hepatic tumour in the cat?

Answer 5

bile duct adenoa

Question 6

Describe the clinical distribution of hepatocellular carcinoma.

Answer 6

• massive (up to 85%) > nodular (up to 25%) > diffuse (up to 19%)
• metastatic rate is up to 37% for massive, and 93%+ with nodular or diffuse
• the L lateral & medial, and the caudate lobes are most commonly affected
• Mini schnauzers?

Question 7

Describe the clinical distribution of hepatocellular adenoma.

Answer 7

Adenoma is more common than carcinoma in cats
- singletons can get quite big, pedunculated

Question 8

Hepatocellular tumours can be divided into 3 groups in the dog based on what?

Answer 8

keratin 19 (k19) staining
<5% = well differentiated

Question 9

Bile duct carcinoma (cholangiocarcinoma) is most common in which species?

Answer 9

Cats! 2nd most common in the dog after HCC

Question 10

Where are the 3 locations for cholangiocarcinoma? Which is the most common location of dogs? cats?

Answer 10

1. intrahepatic
2. extrahepatic
3. within the gallbladder
   - intrahepatic = most common in the dog
   - intra and extra-hepatic = same frequency in the cat
   - within the gallbladder is rare in both species

Question 11

What’s a typical signalment for cholangiocarcinoma in dogs?

Answer 11

female, lab

Question 12

What’s the a typical signalment for cholangiocarcinoma in cats?

Answer 12

there is no breed or sex predisposition in cats

Question 13

What’s the metastatic rate of gallbladder carcinoma in dogs and cats?

Answer 13

dogs: 88%
cats: 78%

Question 14

What’s the most common metastatic location for gallbladder carcinoma?

Answer 14

regional LNs and lungs

Question 15

What’s the common distribution pattern of cholangiocarcinoma in cats?

Answer 15

nodular: up to 54%
massive: 37-46%
diffuse: 17-54%

Question 16

Describe the biological behaviour of hepatic neuroendocrine tumours.

Answer 16

Rare - 3% dogs, 13% cats
aka = hepatic carcinoid
- biologically aggressive
- usually intrahepatic, none surgical, due to diffuse nature
- frequently metastasize –> regional LNs, peritoneum, lungs, etc
- tend to occur at a younger age (7yo)

Question 17

What’s the most common mesenchymal tumour in the liver in cats? dogs?

Answer 17

Cats = hemangiosarcoma
Dogs = leiomyosarcoma

Question 18

What’s the biological behaviour of hepatic mesenchymal tumours in dogs?

Answer 18

Aggressive
- >80% have metastasis to spleen and lungs
- nodular (2/3) > massive (1/3)

Question 19

What are some clinical signs associated with liver tumour?

Answer 19

vague –> lethargy, anorexia, vomiting, weight loss, PU/PD, ascites, pyrexia
- jaundice is more common with bile duct carcinoma and diffuse neuroendocrine tumours in dogs

Question 20

What CBC/ Biochem changes are noted with liver tumours?

Answer 20

CBC:
- anemia: due to chronic disease, RBC sequestration, iron deficiency, loss
- neutrophilia: tumour induced inflammation
- thrombocytosis: 50% dogs of massive HCC
- regenerative anemia, thrombocytopenia: HSA
Biochem:
- elevation in liver values –> not correlated with severity of cancer
- primary liver cancer more likely to cause hypoproteinemia, hypoglycemia, and increase in ALT
- primary liver cancer less likely to cause hyperbilirubinemia
- AST: ALT ration < 1 = HCC or bile duct carcinoma; if >1 = neuroendocrine or mesenchymal

Question 21

How frequent is icterus in cats with biliary neoplasia?

Answer 21

only 1/3!

Question 22

How can alpha fetoprotein be used in hepatic neoplasia?

Answer 22

about 75% of dogs with HCC and 50% of biliary neoplasia will have elevated alpha fetoprotein; but alpha fetoprotein has multiple potential sources in the dog, so it’s not very specific

Question 23

Is CT or MRI better for hepatic neoplasia diagnosis?

Answer 23

MRI has better detection, quantification, and localization vs CT

Question 24

What’s the diagnostic agreement between cytology and histology for hepatic neoplasia in dogs? in cats?

Answer 24

30% agreement in dogs, 50% in cats

Question 25

What’s the treatment for solitary HCC?

Answer 25

surgery

Question 26

What’s the treatment for nodular or diffuse HCC?

Answer 26

can try gemcitabine or mitoxatrone in dogs

Question 27

What’s the treatment for nodular or diffuse biliary duct carcinoma?

Answer 27

no effective treatment

Question 28

What’s the treatment for solitary mesenchymal hepatic neoplasia?

Answer 28

solitary = lobectomyW

Question 29

What’s the prognosis of massive bile duct carcinoma?

Answer 29

still poor - though can be surgically resectable, they are highly metastatic - recur or met within 6m