Neck dissection after chemoradiotherapy for oropharyngeal and hypopharyngeal cancer: the correlation between cervical lymph node metastasis and prognosis

Abstract

Recently, the role of chemoradiotherapy (CRT) for preserving organs in the treatment of head and neck cancer has been increasing. However, the indication for post-CRT neck dissection (ND) and its surgical extent is still controversial. The purpose of this study was to discuss the indications for post-CRT ND and the proper extent of the surgical procedure. We performed a retrospective analysis on N2-3 oropharyngeal and hypopharyngeal squamous cell carcinoma (OHSCC) patients treated with CRT in our institute from 1995 to 2008, and determined the prognostic impact of post-CRT ND and the distribution of cervical lymph node (CLN) metastasis based on the pathological results of ND. The patients without pathological CLN metastases had good prognoses, whereas patients with pathological CLN metastases exhibited a significantly high recurrence rate (P = 0.033). Based on the pathological results of ND, performing selective ND at levels II-IV can contain 88 and 85 % of CLN metastasis of the oropharynx and hypopharynx, respectively. In all cases, when pathological CLN metastases were found at level V in ND following CRT, distant metastases developed. The presence of pathological CLN metastasis affects prognosis, but also a diffuse distribution of CLN metastasis worsens prognosis; that is, the presence of CLN metastasis at level V after CRT appears to be an indicator of distant metastasis. Post-CRT ND may not make sense as a salvage intervention for improving the prognosis in such situations. We concluded that the proper extent of post-CRT ND of OHSCC is selective ND including levels II-IV.