Epidemiological, clinical and pathological evaluation of overall survival in canines with mammary neoplasms

Canine mammary neoplasms (CMNs) are the most frequent lesions and in female dogs. However, studies correlating pathological criteria with clinical evolution in female dogs with mammary neoplasms are scarce. The present study aims to present epidemiological, clinical-pathological and overall survival data to help establish the prognosis and understand the biological behavior of CMNs. A total of 1539 cases were included (85% malignant and 13% benign). Tumor size was an important prognostic factor and was associated with overall patient survival (P<0.0001). Most dogs diagnosed with malignant neoplasms (83%) had initial clinical staging, although 17% had regional or distant metastases at the time of diagnosis and lower overall survival (P<0.0001). Carcinoma in mixed tumor was the most frequent histological type and had a better prognosis. Solid carcinomas, micropapillary carcinomas and carcinosarcomas were considered histological types with aggressive biological behavior and were associated with a worse prognosis and lower overall survival (P<0.0001).