CT for Preoperative Prediction of Axillary Lymph-Node Status in Patients with Breast Cancer

ABSTRACT

BACKGROUND: The clinical staging may serve to guide initial therapy based on all available preoperative data, such as history, physical and laboratory examinations, and biopsy material. Computed tomography is one of the most attractive methods of evaluating the clinical state of patients with breast cancer. In cases where the lymph nodes are enlarged, CT of the chest can accurately detect the level of axillary lymph nodes involvement. CT may also simultaneously play a role in evaluating the mediastinum and the supraclavicular areas for adenopathy, primary tumors and lung metastases. The aim of this study was to determine the appropriate size criteria for metastatic axillary lymph nodes on CT and to evaluate the validity of using CT to detect axillary lymph-node metastases due to breast cancer. METHODS: CT examination of the chest was performed before axillary lymph node dissection in 98 patients with breast cancer. We measured the sizes of the lymph nodes according to the short-axis diameters seen on CT. We estimated the sensitivity, the specificity, the ROC curve, and the predictability of CT based on lymph-node sizes. RESULTS: The diagnostic criterion for node metastases was 5 mm. At the 5 mm point, the accuracy of CT for axillary metastases was 70% with a sensitivity of 89%, a specificity of 60%, a negative predictive value of 90%, and a positive predictive value of 56%. CONCLUSIONS: In conclusion, CT is not an accurate assessment in the diagnosis of axillary lymph-nodemetastases due to breast cancer. However, CT data can be interpreted with sufficient sensitivity and negative predictability for CT to serve as a screening test.