What is the correct terminology for the extension of cancerous cells outside of lymph nodes?

The correct term for the extension of cancerous cells outside of lymph nodes is "extranodal extension." This terminology is specifically used to describe the phenomenon where cancer cells breach the confines of lymph nodes and invade surrounding tissues. It is particularly relevant in managing and staging various cancers, especially lymphomas and certain types of head and neck cancers, as it can significantly affect prognosis and treatment decisions.

Extranodal extension indicates that the cancer has spread beyond where it typically would remain contained (inside the lymph node), suggesting a potentially more aggressive pattern of disease. This condition can prompt more intensive therapy and is a critical factor in determining the stage of the cancer.

The other terms provided refer to different concepts in oncology. "Nodal infiltration" generally describes cancer cells infiltrating the lymph nodes but does not specifically address the concept of extending outside of them. "Metastasis" refers broadly to the spread of cancer from the original site to different areas of the body, which can involve distant organs, not just the invasion of structures adjacent to lymph nodes. "Dermal spread" pertains to the infiltration of cancer through the skin, which is not relevant to the lymphatic system or extranodal involvement. Thus, extranodal extension is the precise term that describes the scenario in