Cardiac neoplasia

Question 1

Incidence

Answer 1

0.1-4%
Uncommon

Question 2

Epidemiology/breeds

Answer 2

 Except lymphoma → can occur at younger age
o Reported breeds at higher incidence: German Shepherd, Golden, Boxer, Bulldog, Boston Terrier, Scottish Terrier, English Setters, Afghan Hound, Flat-Coated Retriever, Irish Water Spaniels, French Bulldogs, Salukis

Question 3

Primary vs metastasis

Answer 3

• Primary cardiac tumors vs metastasis origin varies in reports
  o 84% of cases vs metastatic in 16% (Ware and Hoper)
  o 31% of cases vs metastatic in 69% (Aupperle et al.)
   Consistent with Hu findings
  o Most metastatic lesions (75%) at necropsy
   75% in inner 1/3 of LVFW and IVS
   25% in RA and RVFW

Question 4

Location

Answer 4

o RA/RAA in 63%
 Most HAS
 ↑ tendency to metastasize
o Heart base 18%
o LV 9%

Question 5

C/s

Answer 5

asymptomatic or caused by
o Altered cardiovascular function from mass effect
o Hemorrhage/effusion into pericardium
 Variable incidence of pericardial effusion
 Most common cause is HSA > chemodectoma and mesothelioma

Question 6

Dx

Answer 6

o Aspiration when possible → risk of arrhythmia and hemorrhage
o Endomyocardial transvenous or open chest biospsies
o Cytology of pericardial effusion: variable utility depending on tumor type
 Frequent false + (13%)
 False negative (47%)
 Diagnostic utility ↑ in effusion with PVC <10%
o Tropnoin I
 ↑ with intracardiac vs extracardiac HSA
 ↑ with pericardial effusion
 Not help differentiate etiology
o Echo: location and size of tumor may help differentiate

Question 7

Most common type

Answer 7

HSA

Question 8

HSA: epidemio

Answer 8

• MOST COMMON (69% of cases): highly aggressive/malignant neoplasm of vascular endothelium or hematopoietic precursor 
  o 68-75% metastatic rates based on necropsy
  o Breeds: German Shepherd and Golden Retreivers

o Can be solitary heart tumor or concurrent splenic mass
 Screening after dx of splenic mass: incidence 9-25% for RA mass
 Screening after dx of RA mass: incidence 29% for splenic mass
* Only 42% also had other non splenic matastasis
 Both tumors could be primary

Question 9

HSA: echo

Answer 9

o Mass on RA wall of RAA
 Can protrude into pericardial space, RA lumen
 Spread to other areas of heart base
 Involve R AV groove
o Rarely, diffuse infiltrative tumor
o R or L parasternal view
o Mottled or cavitated appearance with small hypoechoic spaces

Question 10

HSA: definitive dx

Answer 10

• Cytology/biopsy: rarely attempted because of risks of non diagnostic sample/complications

Question 11

HSA: tx

Answer 11

o Pericardiocentesis: 16 days
o Mass resection: 42 days – 4mo
o Chemotherapy (doxorubicin based): 139 days
o Mass resection + chemotherapy: 175 days

Question 12

HBT: features

Answer 12

o Associated with ascending aorta and/or MPA
 Compression/invasion of GAs possible
 Usually slow growing, locally expansive
 Low incidence of metastasis

Question 13

HBT: etiology

Answer 13

neuroepithelial origin
 ChemoR cells of aortic bodies (small cluster cells in adventitia of Ao root)
* Respond to alterations in O2, CO2, pH → modify respiration and BP
 Most commonly chemodectoma or non-chromaffin paraganglioma
* Non functional tumors

Question 14

HBT: DDX

Answer 14

HSA, mesothelioma, ectopic thyroid tissue, adenoma/adenocarcinoma

Question 15

HBT: breeds

Answer 15

brachycephalic → Boston Terrier, English Bullgogs, Boxers

Question 16

HBT: suggested pathophys

Answer 16

 Suggested pathophysiology: chronic hypoxia → stimulation of chemoR → hyperplasia → tumor
* Never proven

Question 17

HBT: tx

Answer 17

o Subtotal pericardectomy: 730 days
o Radiation therapy: takes up to 6 months to shrink tumor

Question 18

Mesothelioma: features

Answer 18

o Malignant neoplasm affecting epithelial cell of serosal surfaces of body cavities
 Causes malignant effusions: pericardial, pleural, peritoneal
o Difficult to differentiate from idiopathic pericardial effusion → reactive mesothelial cells
 Short clinical course and poor px

Question 19

Mesothelioma tx

Answer 19

o Pericardiocentesis: 60 days
o Chemotherapy: 120 days
o Pericardiectomy + chemotherapy: 300 days

Question 20

Lymphoma: features

Answer 20

• Infrequent
• Can affect heart, pericardium, both
  Usually diffuse

Question 21

Lymphoma staging

Answer 21

o Stage V: cardiac lymphoma + pericardial effusion
 Extranodal in organ other than spleen or liver
 Substage b: + c/s
o Worse prognosis overall, but no data for cardiac form specifically

Question 22

Lymphoma dx

Answer 22

o Cytology of pericardial effusion
o Immunohistochemistry → T or B cell origin

Question 23

Lymphoma tx

Answer 23

study of 12 dogs → 157 days
o Pericardiocentesis
o Chemotherapy + pericardiectomy

Question 24

Other tumors: most frequent types

Answer 24

o Ectopic thyroid carcinoma
o Lymphoma

Question 25

Other tumors: less frequent

Answer 25

o Pulmonary carcinoma
o Ectopic thyroid adenoma
o Melanoma
o Mast cell tumor
o Blastoma
o Granular tumor
o Myxoma, myxosarcoma
o Mesenchymoma
o Rhabdomyosarcoma
o Chondrosarcoma
o Fibrosarcoma

Question 26

Rhabdomyosarcoma

Answer 26

 In Hu: reported spontaneous regression
 Reported incidental finding in 1 dog and 1 German Shepherd in RA/RAA

Question 27

Feline tumors: most frequent

Answer 27

• Lymphoma = MOST FREQUENT
  o FeLV testing could be pertinent
  o Metastasis commonly in IVS and LVFW

Question 28

Feline tumos: other types

Answer 28

Less common vs dogs, tend to be malignant
* Chemodectoma
* Pulmonary carcinoma
* Mammary carcinoma

Question 29

Cows tumors

Answer 29

• Lymphoma of RAA
• Hemangiosarcoma

Question 30

Equine tumors

Answer 30

• Mesothelioma
• Lymphoma