Management of the axilla: Conventional tracers vs ICG-fluorescence in sentinel lymph node biopsy

Abstract

The evaluation of regional lymph nodes is part of breast cancer staging. Biopsy of the sentinel lymph node was established, in order to evaluate the condition of the axillary lymph nodes without having to complete an axillary dissection. The concept of sentinel lymph node (SLN) is based on the theory of sequential dissemination of tumor cells through the lymph. When lymphatic dissemination occurs, the invasion initially occurs in the first lymph node that drains lymph from the tumor. This lymph node has been named GS and depending on its negative or positive status, the presence or absence of metastases in the remaining regional lymph nodes can be established. Blue dye (BD) and radioactive isotopes (RI) are routinely used markers for identification of the sentinel lymph nodes during sentinel lymph node biopsy (SLNB) in early stage breast cancer. Unlike the blue dye technique, using radioactive isotopes has lower false-negative rates. Nonetheless, the need of lymphoscintigraphy, the time needed for preoperative injection, and undetected sentinel lymph nodes in some cases cause surgeons to rely only on the combination of blue dye and radioisotopes. At present, indocyanine green (ICG) fluorescence method (ICG-SLNB) is starting to gain more and more field as an alternative to conventional mapping methods. The purpose of this review is to compare ICG with the conventional methods (blue dye and radioactive isotopes) and their role in detection of SLN.