Lymph node Staging methods in mammary tumors in female dogs: palpation x sentinel node biopsy

Métodos para Estadiamento Linfonodal em tumors mamários em cadelas: palpação x pesquisa do linfonodo sentinela


  • Flávia Diniz Valadares
  • Andréa Pacheco Batista Borges
  • Fabrício Luciani Valente
  • Rodrigo Viana Sepúlveda
  • Kelvin Oliveira Rocha
  • Emily Correna Carlo Reis



Mamary tumor, staging, Sentinel Node, blue dye


Breast cancer is one of the most common cancers in both women and female dogs. The lymphnode condition is one of the most important prognostic factors in both species. The main goals of this search are to determine the role of inguinal and axilary palpation preoperatively, to find the sentinel node detection rate using the blue dye technique and its role in predicting metastasis. Fifty female dogs havings mammary tumors were included in this study. The protocol included data collection, clinical examination, blood sampling and radiologic exams before surgery. Blue dye subcutaneous injection was performed just after anesthesia and ten minutes before skin incision. Mastectomy was performed according to the previously established hospital protocol. Eighty-six percent of dogs presented with malignant tumor. Lymph node palpation offered high accuracy, low sensitivity, high speficicity, low positive predictive value and high negative predictive value for metastasis detection. The inguinal sentinel lymph node was detected in 92.3% of the female dogs and the axillary sentinel lymph, in 78.9%. Twenty-five percent of all detected lymph nodes contained metastatic carcinoma. Sentinel node detection rate was high both inguinal and axilary, although sentinel metastasis were rare in both stations. The procedure did not cause any additional morbidity. Thus, the optimal protocol according to this study, is lymph node palpation and, in positive cases, the sentinel node biopsy using the blue dye technique.