Knowing whether cancer has spread to nearby lymph nodes is one of the most important pieces of information in cancer staging — it shapes decisions about further treatment and prognosis. Traditionally, this has meant removing a larger number of lymph nodes to check them, which carries a real risk of complications such as lymphedema, numbness, and delayed healing. Sentinel lymph node biopsy offers a more targeted alternative, identifying the first, most likely node — or nodes — that cancer would spread to, and examining those specifically.

Indocyanine green (ICG) is a fluorescent dye injected near the tumour site, which travels through the lymphatic channels to the sentinel node. Using a specialised fluorescence imaging camera, the surgical team can visualise this pathway in real time, precisely identifying and removing the sentinel node or nodes for pathological examination — often during the same operation as the primary tumour surgery. This targeted approach provides highly accurate staging information while significantly reducing the extent of lymph node dissection required.

ICG fluorescence-guided sentinel node biopsy is used across a range of cancers, including breast cancer, endometrial and cervical cancer, and melanoma, and is incorporated into the surgical plan as determined by the multidisciplinary tumour board based on tumour type, location, and stage.