Sentinel lymph node biopsy: What cancer patients should know

We often hear about lymph nodes when we talk about how cancer spreads. That’s because when cancer starts to spread, it often goes to the lymph nodes first. When treating breast cancer and melanoma, and – increasingly — head and neck cancers and gynecologic cancers, physicians use a diagnostic method called sentinel lymph node biopsy, which looks at a patient’s lymph nodes to determine whether the cancer has spread and what type of cancer treatment is needed. At MD Anderson, our doctors often use sentinel lymph node biopsies because, in many cases, they help better detect cancer. In fact, about 20-30% of “node-negative” patients have disease present in their lymph nodes even though CT scans and/or ultrasound studies suggest that the lymph nodes are negative or do not contain disease. We spoke with head and neck surgeon Stephen Lai, M.D., Ph.D., to learn more.   What is a sentinel lymph node biopsy? Sentinel lymph nodes are an important part of the immune system, and they contain the cells that monitor foreign substances, like bacteria, viruses and cancer. Sentinel lymph node mapping helps to identify the lymph nodes that are at highest risk for containing cancer. A sentinel lymph node biopsy (SLNB) is a surgical approach to identify and remove the sentinel lymph node to determine if the cancer has spread, and if so, how far. In most cases, a negative sentinel lymph node biopsy means the cancer has not spread. A positive biopsy means cancer was found in the lymph node. It could be in other lymph nodes and even other organs. What happens during a sentinel lymph node biopsy?...