Sentinel lymph nodes will be mapped by contrast-enhanced CT lymphography in breast cancer patients. A mixture of 4 mL iopamidol and 2 mL of 1% lidocaine hydrochloride will be used as a contrast agent provided by periaoreolar injection. No later than 10 days after the CT lymphography patients will receive surgical treatment with sentinel lymph node biopsy using the ICG-fluorescence method.

Patients who meet the inclusion/exclusion criteria will undergo the CT lymphography with periaoreolar injection of a mixture of 4 mL iopamidol and 2 mL of 1% lidocaine hydrochloride. Computed tomographic images will be obtained 1, 3, 5, and 10 minutes after administration of the iopamidol. Following enhancement of the lymphatic duct, the first lymph node to show enhancement will be defined as the SLN.

No later than 10 days after the CT lymphography patients will receive surgical treatment. During breast cancer surgery identification of the SLN using the ICG-fluorescence method with injection of 2 ml indocyanine green into the skin of the areola and the biopsy of identified SLN will be performed. The comparison of the results of CT lymphography and SLN biopsy will be administrated by the investigator.

First primary endpoint is to determine the sensitivity and specificity of contrast-enhanced CT lymphography for the preoperative detection of sentinel lymph nodes in breast cancer in comparison with the intraoperative fluorescence method.

Second primary endpoint is to assess the capabilities of contrast-enhanced CT lymphography for detecting metastases in sentinel lymph nodes in breast cancer patients

Secondary endpoint is to identify objective criteria for metastatic lesions of sentinel lymph nodes (SLN), such as 1) the shape of the lymphatic duct; 2) the contrast enhancement of the SLN (full or heterogeneous); 3) the size of the SLN; 4) the form of the SLN; 5) the density of the SLN.