Skill validation study on sentinel lymph node biopsy in breast cancer and the challenges of false-negative, intransit and micrometastatic nodes

Sentinel lymph node (SLN) is the first lymph node(s) in a regional lymphatic basin to receive the lymphatic drainage from a primary tumor. It has been shown that the lymph flows in an orderly and predicted pattern and any metastatic spread from a primary tumor will involve the sentinel node(s) first, before involving other lymph nodes in that lymphatic basin. 1 The tumor status of the SLN could then help to predict the histopathologic status of other lymph nodes draining the tumor. 2, 3 Although it is possible that at times, breast metastasis may skip pass the SLN to involve the second-tier or a higher-level node, this phenomenon is thought to be an uncommon variant of the lymphatic pattern. 4, 5, 6 Studies have also shown a low axillary recurrence rate in the follow-up of patients with negative SLN. (Copied from article)