Page 200 - Feline Cardiology

Chapter 16: Cardiac Neoplasia 203

The few cases describing thoracic radiographic find- received treatment with a protocol comprising
ings in cats with cardiac tumors show that marked L-asparaginase, cyclophosphamide, vincristine, doxoru-
enlargement of the cardiac silhouette is possible, but bicin, and prednisone, and clinical recovery was excel-
evidence of pulmonary metastases is not described. lent with resolution of clinical signs and effusions
Pleural effusion could be expected if a cat had concur- (Brummer and Moïse 1989). Conversely, in another case
rent mediastinal disease (e.g., lymphoma) or congestive treated with prednisone only, no improvement was seen
heart failure induced by a mass effect interfering with by the 5th day of treatment and the cat was euthanized
normal blood flow. (Meurs et al. 1994).
Echocardiography is the noninvasive diagnostic test Surgical removal of a chemodectoma is described in
of choice. In cats with lymphoma, a spectrum of lesions 1 case (Paltrinieri et al. 2004). The procedure was com-
is possible, ranging from focal myocardial infiltrates or pleted successfully but the patient died suddenly 24
a mass lesion (Shinohara et al. 2005) to massive, diffuse hours postoperatively.
infiltration. Myocardium that is infiltrated with lym-
phoma cells is generally mixed in echogenicity and OUTCOME AND PROGNOSIS
may be slightly hyper-, iso-, or hypoechoic to surround-
ing normal myocardium. Pericardial effusion is present The prognosis for cardiac lymphoma is highly variable: Misc. Heart Diseases
in some cases and not in others. Signs suggesting the two dramatically positive responses noted above
that cardiac tamponade might be likely, such as collapse ended with deterioration and euthanasia of the first cat
of the right ventricular free wall, have been present after 4 weeks but survival beyond the 30th week in the
(Brummer and Moïse 1989) or absent (Shinohara second.
et al. 2005). For chemodectoma, treatment appears to be under-
Cats with chemodectoma have echocardiographic taken rarely, and therefore too few instances of treat-
findings that mirror the gross findings listed above: a ment response are known to allow a conclusion to be
characteristically located mass, which is usually of mixed drawn.
echogenicity, with or without pericardial effusion.
REFERENCES

Advanced Testing Boldface font indicates key references.
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A cytologic or histopathologic diagnosis is required for Schoon H-A. Primary and secondary heart tumours in dogs and
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lesions. Fine-needle aspiration and cytologic exam of Brummer DG, Moïse NS. Infiltrative cardiomyopathy responsive to
pleural or pericardial effusion (lymphoma), and of cells combination chemotherapy in a cat with lymphoma. J Am Vet
retrieved from an echocardiographically apparent mass Med Assoc 1989;195:1116–1119.
(chemodectoma), have provided a conclusive diagnosis Caruso KJ, Cowell RL, Upton ML, Dorsey KE, Meinkoth JH, Campbell
GA. Intrathoracic mass in a cat. Vet Clin Pathol 2002;31:
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6% (Zoia et al. 2004) or 16% initially and then 3% 1 Hosp Assoc 2008;44:5–9.
month later (Shinohara et al. 2005). Georg C, Steinberg H. An aortic body carcinoma with multifocal
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Immunophenotyping of feline cardiac lymphoma Harpster NK. The cardiovascular system. In: Diseases of the Cat,
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TREATMENT Meurs KM, Miller MW, Mackie JR, Mathison P. Syncope associated
Medical and surgical therapies are described for cardiac with cardiac lymphoma in a cat. J Am Anim Hosp Assoc 1994;30:
583–585.
tumors in cats. Chemotherapy for lymphoma was suc- Paltrinieri S, Riccaboni P, Rondena M, Giudice C. Pathologic and
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