Effects of postoperative chemotherapy and radiotherapy on patients with squamous cell carcinoma of the oral cavity and multiple regional lymph node metastases.

Nodal metastasis in oral squamous cell carcinoma (OSCC) is considered to be a predictor of a poor prognosis. The aim of this study was to investigate the relationship between the number of positive lymph nodes and the prognosis in OSCC patients with nodal metastases and to assess the effects of postoperative radiotherapy (RT) or concurrent chemoradiotherapy (CCRT) on this patient group. A retrospective investigation of 98 patients with OSCC who underwent radical neck dissection and had at least three pathologically positive lymph nodes was performed. The 5-year disease-specific survival rate was 66.7% for patients with 3 positive nodes, while it was significantly lower for those with 4 positive nodes and those with ≥ 5 positive nodes (21.5% and 46.1%, respectively; P < 0.01). The loco-regional control and disease-specific survival rates for the surgery alone, surgery plus RT, and surgery plus CCRT groups were 46.2% and 40.5%, 66.3% and 54.4%, and 81.7% and 52.4%, respectively. For patients with ≥ 4 positive nodes, the loco-regional control rate after surgery plus CCRT was better than that observed after surgery alone (77.5% vs. 32.6%, P = 0.01). Postoperative RT and CCRT have positive impacts on the prognosis of OSCC patients with advanced stage neck disease.