Final answer:
Metastasis to contralateral mediastinal, contralateral hilar, ipsilateral or contralateral scalene, or supraclavicular lymph nodes is associated with N3 nodal stage in cancer staging, which suggests advanced regional lymph node involvement.
Step-by-step explanation:
The question refers to the classification of lymph node metastasis in the context of staging cancer, specifically with regard to how metastasis to certain lymph nodes corresponds with the N3 nodal stage. In cancer staging, N3 typically indicates advanced regional lymph node involvement. Metastasis to contralateral mediastinal, contralateral hilar, ipsilateral or contralateral scalene, or supraclavicular lymph nodes suggests a higher tumor burden and is important for treatment planning and prognosis. This kind of detailed staging is especially relevant in diseases such as lung cancer, where the presence of cancer cells in lymph nodes distant from the primary tumor (the contralateral side or above the clavicle) indicates a more widespread disease.