Metastases to Regional Lymph Nodes in Breast Cancer: Current Views of Detection Methods

In Russia, breast cancer is the most prevalent oncological pathology among female patients, accounting for approximately 22.5% of all cancer cases. Approximately 90% of mortalities associated with this condition are attributed to the metastasis of cancer cells. Consequently, the effective detection of metastases within the regional lymphatic system during breast tumor progression is a critical diagnostic component. In recent decades, methodologies for verifying metastatic regional lymph nodes in breast cancer patients have advanced significantly, demonstrating high efficacy. The identification of sentinel lymph nodes became feasible through the use of various dyes, radioisotopes, and superparamagnetic nanoparticles. Detection techniques for metastatically affected formations include radioisotope lymphoscintigraphy, single-photon emission computed tomography (SPECT) often in combination with computed tomography (CT), and positron emission tomography (PET) typically integrated with CT. The accumulated data enabled an assessment of the advantages and limitations of current diagnostic methods. Radioisotope lymphoscintigraphy offers minimal invasiveness, high accuracy, and a low risk of complications; however, it remains insufficiently safe and cost-prohibitive. The application of superparamagnetic nanoparticles exerts negligible adverse effects on the human body and is characterized by straightforward administration. However, this method remains understudied, with its implementation being limited. Although the SPECT in combination with CT offers high sensitivity, thereby facilitating precise sentinel lymph node localization, it is associated with. exposure to ionizing radiation for the patient and the associated high procedural costs. Published data confirm the significance and efficacy of modern techniques for verifying metastatic regional lymph nodes in breast cancer. Therefore, the optimal diagnostic approaches can be selected, while reducing the invasiveness of mastectomy and lymph node dissection, improving survival rates, and decreasing the probability of recurrence or cancer progression.