Computed Tomography for Preoperative Evaluation of Axillary Nodal Status in Breast Cancer

BACKGROUND: We prospectively evaluated axillary lymph node metastasis by preoperative thin-slice computed tomography (CT) and compared those results with theresults of dye-guided sentinel lymph node biopsy (SNB). PATIENTS AND METHODS: Fifty-one breast cancer cases were examined. Preoperative axillary CT, dyeguided SNB and complete axillary lymph node dissection were performed. We prospectively diagnosed lymph node metastasis in the whole axillaryregion and qualitatively predicted the sentinel lymph node (SN) status with thepreoperative CT images. Based on the results of SNB and the pathological nodal status as revealed by complete axillary dissection, we evaluated the usefulness of preoperative axillary CT as a predictor of axillary node metastasis, and we also investigated the qualitative diagnostic value of the SN predicted by CT. RESULTS: For the whole axillary region, the results of CT diagnosis showed anaccuracy of 71% and a sensitivity of 60%. The SN predicted by CT correlated with the SN identified by the dye-guided method in 86% of all cases. The SN status predicted by CT had an accuracy of 81%, a sensitivity of 78%, and a negative predictive value of 79%. The dye-guided methods resulted in three false-negative SNcases, however, CT predicted one of those cases as positive. CONCLUSIONS: Diagnosis of axillary lymph node metastasis by CT alone is inadequate. However, CT achieves a comparatively high rate of identification of axillary SN. The combined use of dye-guided SNB and preoperative CT will facilitate identification of the SN and also lower the false-negative rate.