Stage IVB includes: T0, N3, M0. T0: No evidence of primary tumor. N3: Metastasis in a cervical lymph node larger than 6 cm in greatest dimension and ENE(-); or metastases in a single ipsilateral cervical lymph node larger than 3 cm in greatest dimension and ENE(+); or metastases in multiple ipsilateral, contralateral, or bilateral cervical lymph nodes, any size and ENE(+) in any node. M0: No distant metastasis. (AJCC 8th Ed.) [from
NCI]