Characterization of canine neoplasms diagnosed by histopathology at the laboratory of Histology and Pathology Veterinary of the Universidad Peruana Cayetano Heredia: period 2003-2015

The aim of this study was to determine the frequency of canine neoplasms diagnosed by histopathology during the period 2003-2015 at the Laboratory of Histology and Veterinary Pathology of the Universidad Peruana Cayetano Heredia (Lima, Peru). All recorded cases (n=2620) were revised and 46.3% were used for this study. The morphological diagnosis was reclassified according to the "International Histological Classification of Domestic Animal Tumors" (WHO-AFIP), excluding breast tumours that were classified according to Goldschmidt et al. (2011). Sex, age, breed, anatomic location of the sample, morphological or clinical characteristics and the degree of malignancy were statistically analysed. Squamous cell carcinoma was the most frequent neoplasm (7.7%), with females and geriatric patients being the most affected (60.7 and 54.4%, respectively). Purebreds had the highest prevalence of neoplasms (64.3%). In addition, the presence of a tumour was the most frequent clinical presentation (93.7%), being located mainly in the integumentary system (51.2%) and the mammary gland (23.6%). Besides, 72.1% of the neoplasms exhibited malignant characteristics. An association was found between the malignancy of the tumours with the presence of an inflammatory process. Further evaluation by immunochemistry is required to obtain an accurate diagnosis.