Avaliação de metástases de carcinoma mamário em cadelas: localização, tamanho, tipo histológico e correlação com sobrevida

Abstract

Breast tumors are the most frequent in non-castrated bitches. Most of the confirmed cases are malignant neoplasms, which may present metastatic characteristics. Knowing that the presence of metastases is an important prognostic factor in bitches with mammary neoplasms, the present study aimed to determine the clinical staging of bitches with malignant mammary tumors seen at the Veterinary Hospital of the Federal University of Uberlândia, and to verify the influence of the factors: presence of metastases (regional or distant); size of distant metastases (pulmonary and/or abdominal) and histological type on the survival time of these animals. We selected 118 female dogs that received veterinary medical care at HV-UFU between January 2019 and December 2020. The bitches were staged and the Kaplan-Meier method was used to calculate the overall survival (SG) curve, followed by the Log Rank test for comparison of the survival curves. The mean overall survival (OS) of female dogs with mammary carcinoma was 706.964 ± 39.994 days. The histological type tubulo-papillary carcinoma was the most frequently observed (29.66%). According to the TNM classification system, 46.61% (55/118) bitches were stage I, 10.17% (12/118) II, 13.56% (16/118) III, 6.78% (8/118) IV and 22.88% (27/118) V. Bitches in stage I achieved the highest mean survival (p=0.000). The mean survival of bitches with the different histological types of mammary carcinomas was 798.301 ± 40.026 days. The mean survival time of animals with regional or distant metastases was shorter compared to those without metastases (p=0.010). Bitches with lung metastases had shorter survival compared to bitches with metastases in other organs (p<0.001). The size of metastatic nodules did not influence the mean SG of bitches with mammary tumors. We conclude that the presence of regional or distant metastases in bitches with mammary neoplasms determines a worse prognosis and has a negative influence on the survival time of these animals.