Can Nomograms Predict Preoperative Axillary Lymph Node Metastasis in Patients With Breast Cancer to Guide Second Look Ultrasonography?

Abstract

The low sensitivity of ultrasonography (US) for diagnosing axillary lymph node metastasis in patients with breast cancer has led to the development of multiple tools in an attempt to increase preoperative sensitivity, including second-look US. We compared axillary lymph node metastasis predictor scores with postsurgical findings, using the Memorial Sloan Kettering Cancer Center (MSKCC; New York, NY) and Evidencio (www.evidencio.com) nomograms: 2 freely available online predictor tools. We retrospectively evaluated 450 patients with breast cancer and analyzed data from 194 patients. Sonograms were evaluated to measure lymph node cortical thickness, transverse diameter, and hilum status. Patients were divided into 3 groups: namely 0, 1, and 2 based on the number of postoperative positive nodes (0, 1 and ≥2, respectively). One-way analysis of variance was used to analyze the differences in mean scores across the 3 nodal groups for both nomograms. P < .05 was considered statistically significant. There were significant differences in mean scores across the 3 nodal groups when using MSKCC (P < .001) as well as Evidencio (P < .001). However, there was an overlap of scores across the 3 groups; thus, mutually exclusive values were not obtained. A strong positive correlation was found between MSKCC and Evidencio (P < 0.001). Tumor size and the presence of lymphovascular invasion were significantly associated with axillary nodal disease (P < .001; P = .003, respectively). The use of nomograms to predict axillary nodal involvement in patients with breast cancer can guide discussions, but in their present state, these scores cannot guide clinical decisions or direct second-look US of axilla.