If you have penile cancer (cancer of the penis), a sentinel lymph node biopsy (SNLB) is a way of checking the smallest possible number of lymph nodes in the groin to see if they contain cancer cells. The sentinel node is the first node that lymph fluid from the penis drains to. This means it is the node most likely to contain any cancer cells. There may be more than one sentinel node.
Your cancer doctor will talk to you about whether an SLNB is suitable for you. They will help you decide whether to have the test or not.
You have an SLNB done under a general anaesthetic. The surgeon injects a blue dye and a tiny amount of harmless, radioactive liquid into the area of the cancer. The dye drains into the sentinel lymph nodes and turns them blue. The surgeon uses a small, hand-held instrument to find the lymph nodes that have picked up the radioactive liquid. They remove any blue or radioactive nodes (sentinel nodes) through a small cut in the groin.
If the sentinel nodes do not contain cancer, it is very unlikely that any other lymph nodes will. This means you will not need to have any more lymph nodes removed. If there are cancer cells in any sentinel nodes, you will need more surgery to remove the rest of the lymph nodes.