Prevalence of mammary neoplasms and evaluation of surgical margins in bitches: a retrospective study

Abstract

In surgery for removal of mammary neoplasms, the achievement of free margins is important to predict the effectiveness of the procedure. The aim of this study was to evaluate the relationship between margins and clinical and histopathological findings in bitches with mammary neoplasms submitted to surgical excision. A retrospective study was conducted from 2016 to 2020, of 170 bitches diagnosed with malignant mammary neoplasia, where information was obtained regarding: evaluation of the margins, location, size, clinical presentation, degree of adhesion, degree and histopathological classification of neoplasms and the involvement of regional lymph nodes. Margins were compromised in 11 (6.5%) patients. The most frequent malignant neoplasms were mixed tumor carcinoma (n=83, 29.64%). Patients with anaplastic carcinoma (n=6, 2.14%) were more likely to have compromised margins (p= 0.050), and patients with malignant adenomyoepithelioma (n=13, 100%), more likely to have free margins (p=0.021). Patients who had lymph nodes with metastases were more likely to have compromised margins (p=0.041). We can conclude that the histopathological findings are related to surgical margins, while the clinical parameters evaluated, such as location, size and presentation did not interfere. Patients affected with anaplastic carcinomas had a greater chance of having compromised margins, while those affected by malignant adenomyoepithelioma tended to have surgical margins free of neoplasia.