Currently, most protocols of nasopharyngeal carcinoma (NPC) of various research bodies such as the Radiation Therapy Oncology Group require routine elective irradiation to the retropharyngeal area and to levels II-V lymph nodal areas regardless of the status of nodal metastasis. Previous studies had confirmed that the pattern of cervical lymph node (LN) metastasis in NPC followed an orderly manner. Retropharyngeal LNs were the most commonly involved, followed by upper neck levels II, III, or VA nodes, and finally to the lower neck nodes including level IV and VB nodes; and the incidence of LN skip metastasis is rare, ranging from 0.5% to 7.9%. It was rare for NPC patients without neck LN metastases to experience neck failure after elective irradiation to levels II, III and VA. It was also confirmed that with unilateral LN metastases of higher-level LNs usually spread down ipsilateral LNs. Thus, the investigators conduct the non-inferior randomized trial to determine the value of elective neck irradiation in NPC patients with unilateral or bilateral uninvolved neck.
Currently, most protocols of nasopharyngeal carcinoma (NPC) of various research bodies such as the Radiation Therapy Oncology Group require routine elective irradiation to the retropharyngeal area and to levels II-V lymph nodal areas regardless of the status of nodal metastasis. Previous studies had confirmed that the pattern of cervical lymph node (LN) metastasis in NPC followed an orderly manner. Retropharyngeal LNs were the most commonly involved, followed by upper neck levels II, III, or VA nodes, and finally to the lower neck nodes including level IV and VB nodes; and the incidence of LN skip metastasis is rare, ranging from 0.5% to 7.9%. It was rare for NPC patients without neck LN metastases to experience neck failure after elective irradiation to levels II, III and VA. It was also confirmed that with unilateral LN metastases of higher-level LNs usually spread down ipsilateral LNs. Thus, the investigators conduct the non-inferior randomized trial to determine the value of elective neck irradiation in NPC patients with unilateral or bilateral uninvolved neck.