Accuracy of Predicting Axillary Lymph Node Positivity by Physical Examination, Mammography, Ultrasonography, and Magnetic Resonance Imaging

Background. Axillary lymph node status continues to be among the most important prognostic variables regarding breast cancer survival. We were interested in our ability to accurately predict axillary nodal involvement by using physical examination and standard breast imaging studies in combination. Methods. A retrospective review was performed of 244 consecutive patients diagnosed with invasive breast carcinoma between May 2008 and December 2010 who underwent physical examination of the axilla, digital mammography, axillary ultrasonography, and contrastenhanced breast magnetic resonance imaging and who had subsequent histopathologic evaluation of one or more axillary lymph nodes. Results. A total of 62 (25%) of 244 women were found to have positive axillary lymph nodes on final histopathologic examination, 42% of whom were able to be identified preoperatively. The sensitivity for predicting axillary metastasis if any one or more examination modalities were suspicious was 56.5%. The specificity for predicting axillary metastasis if any three or more modalities were suspicious was 100%. Of the patients who had all four modalities negative, 14% were ultimately found to have histologically positive nodes at the time of surgery. Conclusions. Physical examination and multimodal imaging in combination are useful for preoperative axillary staging and treatment planning. However, they remain inadequate definitive predictors of axillary lymph node involvement.