Preparation 'UNIMAG' is registered by the pharmacological committee of Georgia (Cert.: DA Nr-000142, 08.04.2005; Author – PhD, ScD, Professor Besiki Surguladze; Owner – 'ATT' Ltd, Sci. Laboratory 'Magnetic fluids in Medicine and Biology'). Preparation 'UNIMAG' represents a magnet-sensitive stabile suspension of magnetite nano-particles (magnetic fluid). After the peritumoral injection of 'UNIMAG', magnetite nanoparticles will be absorbed by macrophages, which deliver them through the lymphatic capillaries to regional lymph nodes. This mechanism of magnetite nanoparticle transport underlies the new method of sentinel lymph node detection. Diversely to the other dyestuff agents used in this direction, magnetite nanoparticles actively filled lymphatic nodes and colored them in bold black. This significantly facilitates the atraumatic separation of lymph nodes during lymphadenectomy. Besides the intraoperative indication of lymphatic nodes, 'UNIMAG' provides the possibility of X-ray and ultrasound imaging of sentinel lymph nodes and performing their biopsy in the preoperative period. This assuredly helps in a better planning of the operation and considerably improves its radicalism. Even in the case of ideal surgical intervention it is impossible to remove all the microscopic lymphatic vessels and nodes that could be damaged by the tumor micro-metastasis. In the field of high-frequency electromagnetic waves, the magnetite nanoparticles give us possibilities of local, distance hyperthermia on micrometastatic lesions. This minimizes the potentiality of development of postoperative recurrence and secondary metastatic processes.