Objective: Determining the presence of metastasis in the axillary lymph nodes using preoperative data in breast cancer has been studied previously. Formulas and nomogram programs that calculate the relationship between parameters and axillary lymph node metastases are presented. It is controversial whether current calculations give the same accuracy across all ethnic groups. We aimed to validate the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram results for the prediction of sentinel lymph node (SLN) metastasis in patients with breast cancer in Turkey. Method: The clinical records, pathology results, and surgery reports of 400 patients who underwent surgery were examined. Sensitivity, specificity, positive and negative predicated values, and area under the curve (AUC) values were calculated using a nomogram developed by the MSKCC. Results: Frozen section results of SLN examination of the patients were positive in 101 of the 400 patients. The relationship between nomogram calculation and sentinel positivity was evaluated using the receiver operating characteristic curve (ROC); AUC 0,699, p