[Historical evolution of the sentinel lymph node]

The sentinel node is the first lymph node reached by metastasising cells from a primary tumour. Numerous studies have confirmed and demonstrated the reliability of the sentinel node biopsy hypothesis, on account of the high identification rate and overall accuracy of dye-guided and radio-guided procedures. It is remarkable that the concept of lymphatic mapping was not introduced until the end of the twentieth century. The development of the dynamic technique of intraoperative lymphatic mapping in the 1990s resulted in general acceptance of the sentinel node theory. The current literature suggests that sentinel node biopsy may eventually replace axillary dissection as the nodal staging procedure of choice in early breast cancer. This report describes the history and validation of the sentinel node biopsy technique, with particular reference to breast cancer.