Epidemiological aspects of canine mast cell tumors assisted at the oncology service of the Federal Rural University of Rio De Janeiro
Epidemiological; Neoplasm; Mast Cell tumors
Mast cell tumors are the most common malignant skin tumors in dogs, being classified as a round cell tumor that can manifest clinically as skin formations of different sizes and appearances. The prognostic evaluation of mast cell tumor is complex due to its varied biological behavior, factors such as location, clinical signs associated with the tumor, growth rate, size, presence of paraneoplastic syndromes, race, sex and clinical staging can influence the prognosis. Epidemiological studies in Brazil are scarce, so the aim of this study was to evaluate the distribution of clinical characteristics of mast cell tumor and analyze the risk of developing this neoplasm in relation to other skin tumors in patients attended by the oncology service of the Veterinary Hospital of the University Federal Rural of Rio de Janeiro. The retrospective epidemiological study included 266 dogs affected by cutaneous mast cell tumors with a reference group of 581 patients diagnosed with other cutaneous tumors; the mean age of the patients was 9 years, with females being more affected than males; most patients were mongrel dogs, followed by Boxer, Labrador, Pitbull and Pinscher; clinical signs such as vomiting, melena, pruritus, cachexia, hemorrhage, diarrhea, seizures, syncope, skin bruises and prostration were found in 14.3% of patients. The most affected body regions were the trunk and pelvic limbs. Anemia, neutrophilia, eosinophilia, and thrombocytopenia were common findings in affected dogs; surgery was the treatment chosen for most patients and the chemotherapy protocol of vinblastine with prednisolone was the most used. A predisposition was identified in the Boxer, Pinscher, Pug, French Bulldog and Sharpei breeds, contrary to the Poodle, Cocker Spaniel and Rottweiler breeds that presented a lower risk of developing mast cell tumor.