Cardiac Tumors in Dogs: 1982–1995

Abstract

A Veterinary Medical Database search from 1982 to 1995 identified 1,383 dogs with tumors of the heart from a total population of 729,265 dogs (0.19% incidence). Hemangiosarcoma (HSA) was the most common cardiac tumor identified. In the subset of dogs with specific histologic diagnoses, the number with HSA was almost 10-fold that of the 2nd most common tumor, aortic body tumor. Primary heart tumors were more common than cardiac metastases. When biologic behavior was noted, most heart tumors were classified as malignant. Cardiac tumors (excluding lymphoma) occurred most often in dogs between the ages of 7 and 15 years. In very old dogs (>15 years), the frequency of cardiac tumors was the same or lower than that of the youngest age group. Tumors occurred with similar frequency in males and females, but the relative risk for spayed females was >4 times that for intact females. For HSA, spayed females had >5 times greater relative risk than did intact females. The risk for castrated males was slightly greater than that for intact males, which had 2.4 times the relative risk of intact females. Thus, neutering appeared to increase the risk of cardiac tumor in both sexes. Intact females were least likely to develop a cardiac tumor, whereas spayed females were most likely to develop a tumor. Twelve breeds had greater than average risk of developing a cardiac tumor, whereas 17 had lower risk.

Thrombotic complications associated with atrial fibrillation in three dogs

“…Other than a thrombus, the main differential diagnosis for the echodense left atrial masses noted in the first two cases is intracardiac neoplasia. However, the left atrial chamber is a very uncommon location for cardiac neoplasia in dogs, 18 and neoplasia is considerably less likely to be found in association with AF than thrombus. Furthermore, the severity of the structural heart disease in Case 1 and the resolution of the mass with anticoagulation in Case 2 support the working diagnosis of intra-atrial thrombus.…”

Cardiac Tumors

“…However, neutering seems to increase the risk of cardiac tumors in both sexes. In dogs, the most common primary cardiac tumors are right atrium hemangiosarcomas [3,4] and chemodectomas [5]. The frequency of hemangiosarcomas is almost 10 times that of chemodectomas [5].…”

“…In dogs, the most common primary cardiac tumors are right atrium hemangiosarcomas [3,4] and chemodectomas [5]. The frequency of hemangiosarcomas is almost 10 times that of chemodectomas [5]. Less common heart tumors include granular cell tumors [6], chondrosarcomas [7], osteosarcomas [8], fibromas [9], fibrosarcomas [10,11], cardiac lipomas [12], malignant mesenchymal tumors [13], lymphomas [14,15], rhabdomyosarcomas [16,17], neurofibromas [18], angiolipomas [19], myxomas [20][21][22][23], right atrial myxosarcomas [21,24,25], ectopic thyroid carcinomas [26][27][28], and pericardial mesothelioma ( Figure 18-1) [1,5].…”

“…Chemodectomas are more frequently found in brachycephalic breeds (Boxer, English Bulldog, Boston Terrier), while HSA is more prevalent in German Shepherds, American Cocker Spaniels, English Setters, Golden Retrievers, Labrador Retrievers, and Miniature Poodles [4,5].…”

“…Other tumors in this area, less frequently encountered, are ectopic thyroid carcinomas [27] and lymphomas [5,14]. There are differences of echogenicity (homogenous or heterogenous tissue, degree of echogenicity), site of origin, dimensions, shape, location, contour (smooth or irregular), mobility, infiltration, single or multiple lesions, unilocular or multilocular structures, and growth type, which can help to differentiate these types of tumors.…”