Comparative pathology of bone tumors in animals, with particular emphasis on the dog

A review of bone tumors in animals, based on cases reported in the literature and on personal examination of cases from several universities in the U.S.A. and Europe, has shown that: 1. The following bone tumors occur in decreasing order of frequency in animals: osteosarcoma, chondrosarcoma, osteochondroma, hemangiosarcoma, fibrosarcoma, and liposarcoma; 2. The dog has by far the highest frequency of bone tumors; and osteosarcomas account for approximately 80 percent of bone tumors in dog, followed by chondrosarcomas and hemangiosarcomas; 3. Bone tumors occur less frequently in the cat than in the dog, and are of essentially the same types and incidence as in the dog; 4. Sheep has a unique propensity for chondrosarcoma and primary bone tumors are rare in other species; 5. Giant cell tumors, reticulum cell sarcomas, and Ewing's sarcomas are exceptional findings in animals.