Source:http://linkedlifedata.com/resource/umls/id/C0280384
NCI: Stage IV includes: IVA: (T4, N0, M0); (T4, N1, M0); (T4, N2, M0); IVB (Any T, N3, M0); IVC (Any T, Any N, M1). T4: Nasopharyngeal cancer with intracranial extension and/or involvement of cranial nerves, hypopharynx, orbit, or with extension to the infratemporal fossa/masticator space. N0: No regional lymph node metastasis. N1: Nasopharyngeal cancer with unilateral metastasis in cervical lymph node(s), 6 cm or less in greatest dimension, above the supraclavicular fossa, and/or unilateral or bilateral, retropharyngeal lymph nodes, 6 cm or less in greatest dimension. Midline nodes are considered ipsilateral nodes. N2: Nasopharyngeal cancer with bilateral metastasis in cervical lymph node(s), 6 cm or less in greatest dimension, above the supraclavicular fossa. Midline nodes are considered ipsilateral nodes. N3: Nasopharyngeal cancer with metastasis in a lymph node (s) more than 6 cm in greatest dimension and/or to supraclavicular fossa. Supraclavicular zone or fossa is relevant to the staging of nasopharynge