Neoplasmas nasossinusais em cães: aspectos clínico-epidemiológicos, macroscópicos e histopatológicos

Abstract

The occurrence of nasosinusal neoplasms in dogs is considered to be very low, therefore studies related to these neoplasms are scarce. They can be either benign or malignant neoplasms, however most of them are classified as malignant. Due to the anatomical and histological characteristics of the nasal cavity and sinuses, neoplasms of different histological origins may arise, due to their diversity of epithelia that line these cavities and the presence of adjacent bone and cartilaginous structures. This study aimed to carry out a retrospective survey from 2000 to 2019, counting for all cases of nasosinusal neoplasms in dogs in that period, among all cases of biopsies and necropsies in this species. The sex, breed, age, skull conformation, the main clinical signs and the anatomopathological characteristics (distribution, macroscopy and histology) were also computed. During this period, 49 dogs were affected by neoplasms in these regions, totaling 50 neoplasms (one dog had two neoplasms of different location and histogenetic origins). Similar amounts of mixed breed dogs (25/49) and defined breed dogs (24/49) were affected, these distributed in 16 breeds. Among dogs with defined breed, it was noted that dogs with mesocephalic cranial conformation (12/24) were the most affected, followed by dolichocephalic (10/24) and brachycephalic (2/24). There were 22 cases in males and 27 in females, making a proportion of 1:1.23. There was an age variation from 11 months to 16 years; the epithelial neoplasms having occurred in older dogs when compared to those of other histogenic origins (mesenchymal and other origins/round cells). The main clinical signs were similar between the histogenetic categories, being related to the involvement of the upper respiratory tract, sometimes accompanied by nervous signs (when there was brain invasion of nasal neoplasms or vice versa). The possible origin site was mostly in the nasal cavity in relation to the paranasal sinuses (and other locations). Invasions occurred in different tissues adjacent to the nasal cavity and paranasal sinuses, resulting in cranial and facial deformities (21/49). The frequency was 48% of epithelial neoplasms, 32% of mesenchymal neoplasms and 10% of neoplasms with other origins and round cells. The neoplasms most frequently observed, in decreasing order of frequency, were: adenocarcinoma (9/50), squamous cell carcinoma (9/50), transmissible venereal tumor (5/50), osteosarcoma (5/50), chondrosarcoma (4/50) and undifferentiated sarcoma (4/50). Through this study it was possible to establish the frequency of these neoplasms in 20 years, as well as their clinical, macroscopic and histological characteristics.