Occurrence of tumors in domestic animals. Data from 12 united states and canadian colleges of veterinary medicine 12

Abstract

The distribution of 8,634 tumors among 202,277 animal patients reported to the Veterinary Medical Data Program by 12 colleges of veterinary medicine in the United States and Canada is reported. Relative risk and relative frequency analyses revealed a number of differences in tumor distributions within and between the 4 main species categories: bovine, equine, feline, and canine. The proportions, for each species category, of all tumors that were malignant were: cattle 70%, cats 69%, dogs 40%, horses 26%. The eye was the most frequent site for tumors in cattle, the skin for horses and dogs, and the hemic and lymphatic systems for cats. Tumors in cattle had the narrowest spectrum of cell types,- those in dogs the widest. The only unusual sex-related finding was a significantly increased risk of malignant tumors for females in the bovine category. An increasing tumor risk with age was seen in all 4 species,- tumors in the equine species, however, appeared to be less age dependent than the other 3 species categories. A significantly increased tumor risk was noted in 1 bovine,2 equine, and 14 canine breeds, as compared to all breeds within each species category. It is suggested that the data, while subject to limitations of case ascertainment and availability of truly representative reference populations, were sufficiently consistent with what is known about tumors to be considered a reasonable approximation of the distribution of tumors in the species studied,- they cannot, however, be viewed as morbidity statistics.—J Nat Cancer Inst 47:,1971. © 1971 Oxford University Press.