Evaluation of lymph nodes is part of the staging of the mammary tumors and helps to establish a prognosis and therapy. B-mode ultrasonography was used to evaluate size, edge, nodal borders, shape, architecture, echotexture and echogenicity of lymph nodes and Doppler ultrasonography to evaluate the quantity and distribution of the vessels. The aims of this work were to identify which ultrasound features can be used to classify a lymph node as metastatic or non-metastatic; to establish its accuracy as a useful tool to this differentiation, and to establish procedures that permit the reproducibility of the results. Sixty seven lymph nodes of 30 female dogs with mammary tumors were examined by ultrasound and classified as metastatic or non-metastatic. The ultrasonographic diagnostic impression was confronted with the histopathologic results. The ultrasonographic classification of the lymph nodes was correct in 92.5% of the cases, with sensibility of 94.1%, specificity of 92%, positive predictive value of 0.8, and negative predictive value of 0.9787.The characteristics of the nodes to classify them as metastatic or non metastatic were registered. Ultrasound imaging of regional lymph nodes is important to detect metastases and it is suggested that it becomes a regular procedure in the staging of canine mammary tumors.
Ultrasonography lymph nodes; mammary tumors; metastases; bitches
