The Diagnostic Accuracy of Multidetector Row CT for Evaluating the Axillary Lymph Nodes in Patients with Breast Cancer

ABSTRACT

PURPOSE: We investigated the CT (computed tomography) findings of metastatic lymph nodes (LNs), and we analyzed the diagnostic performance of multidetector row CT (MDCT) for detecting axillary LN metastases in patients with breast cancer. MATERIALS AND METHODS: We investigated 59 patients who preoperatively underwent chest MDCT, and they underwent sentinel LN biopsy or whole axillary LN dissection. We analyzed the morphologic features, the degree of enhancement and the delayed enhancement pattern. We classified the patients into the non-metastatic LN group and the metastatic LN group, and we calculated the diagnostic performance of MDCT for detecting metastatic LNs. RESULTS: When both the morphologic and quantitative criteria were consistent, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 58.1%, 100%, 100% and 68.3%, respectively, and MDCT accurately detected metastatic LNs in 2 patients that were false negative on sentinel LN biopsy. When the morphologic and quantitative criteria were consistent, the sensitivity, specificity, PPV and NPV were 87.1%, 53.6%, 67.5% and 78.9%, respectively. However, MDCT could not detect metastatic LNs, including two micrometastases (a total of 8 micrometastases) that were in each of four patients. CONCLUSION: MDCT can be used to perform the morphology and quantitative analysis of axillary LNs, and this modality has excellent specificity and a PPV for detecting metastatic LNs when the both of the diagnostic criteria are consistent.