Evolution of treatment and high-risk features in resectable locally advanced Head and Neck squamous cell carcinoma with special reference to extracapsular extension of nodal disease.

The employment of surgery as a single treatment modality for patients with resectable locally advanced head and neck squamous cell carcinoma (HNSCC) has been associated with high rates of locoregional recurrences even after adequate resection. The addition of postoperative radiotherapy (RT) as adjuvant to surgical resection for advanced HNSCC was investigated in an effort to decrease locoregional failure rates and improve treatment outcome. The unsatisfactory results in terms of locoregional control (LRC) and survival rates achieved with postoperative RT in patients with high-risk features have led to the necessity of exploring the role of concurrent chemotherapy in the adjuvant treatment in resectable advanced HNSCC with confirmed presence of high-risk pathological features. Two prospective randomized independent trials designed and conducted by Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC) demonstrated that the addition of cisplatin-based chemotherapy improved LRC and disease-free survival (DFS). Significant improvement in overall survival (OS) with the use of postoperative concurrent chemoradiotherapy (CCRT) was observed in the EORTC trial. High-risk pathological features in patients with resected head and neck cancer representing adverse prognostic factors that are predictive for local and/or regional recurrence are related to the primary tumor and/or metastatic lymph nodes in the neck. Extracapsular extension (ECE) of nodal disease in the neck has been confirmed as a high-risk pathological feature negatively influencing LRC and survival in patients treated with either postoperative RT or postoperative CCRT. This article reviews the historical progress in the management of resectable locally advanced HNSCC and the impact of ECE on clinical outcome in patients treated with adjuvant therapy following surgery. It can be concluded that strong evidence exists for an improved outcome for high-risk resected patients treated with adjuvant CCRT. Precise definition of the presence of ECE is highly recommended in order to provide proper selection of patients who would benefit from the postoperative CCRT.