Lymph Node involvement
This describes whether lymph nodes near the primary melanoma also contain melanoma.
The lymph nodes may contain enough melanoma to be found when your medical team examine you or might be seen on a scan. Alternatively the lymph nodes may contain microscopic deposits of melanoma that are only found when a pathologist looks at your lymph node under a microscope. The N stage will also be used to describe whether there has been any spread of the melanoma to skin near the primary melanoma. Separate deposits of melanoma are occasionally found close to the original melanoma site. These are referred to as In-transit metastases if they are further than 2cm from the primary tumour, or satellite metastases if they are closer than 2cm.
- N0 – no lymph node involvement
- N1 – 1 involved lymph node or in-transit, satellite, and/or microsatellite metastases
- N2 – 2 or 3 involved nodes or in-transit, satellite, and/or microsatellite metastases with one involved node
- N3 – 4 or more involved nodes or in-transit, satellite, and/or microsatellite metastases with two or more involved nodes, or any number of lymph nodes that have stuck together without or with in-transit satellite, and/or microsatellite metastases
Your pathologist will also take into account whether the lymph node that was involved with melanoma was obvious to your medical team, or whether it was an unexpected finding only seen using a microscope. Your ‘N’ stage will be assigned a letter a, b or c which takes into account whether the melanoma was obvious to your medical team in the clinic, and whether melanoma was found only in a lymph node or had also formed micro-satellite or in transit deposits. The more melanoma that is found in a lymph node or in nearby skin, the greater the chance of further problems arising in the future.