Extracapsular spread: A significant predictor of treatment failure in patients with squamous cell carcinoma of the tongue

INTRODUCTION. The presence of nodal metastases remains the most significant predictive factor for regional recurrence and survival in patients treated for squamous cell carcinoma of the head and neck. Survival rates are further decreased in patients with nodal metastases that have spread beyond the lymph node capsule, or extracapsular spread (ECS). To the authors' knowledge, this is the first report on the impact of ECS in a large series of patients treated for squamous cell carcinoma of the oral tongue (SCCOT) at a single institution using surgery as the primary treatment modality. METHODS. The authors retrospectively reviewed the medical records of all patients treated for SCCOT with resection of the primary and neck dissection at a single institution between 1980 and 1995. RESULTS. Two hundred sixty-six patients were included in the study. Of that number, 146 patients (55%) were pathologically node-negative (pN0), 75 patients (28%) were pathologically node-positive (pN+) without ECS (pN+/ECS-), and 45 patients (17%) were pN+ with ECS (pN+/ECS+). The 5-year disease-specific and overall survival rates for pN0 patients were 88% and 75%; for pN+/ECS- patients, 65% and 50%; and 48% and 30% for pN+/ECS+ patients. The patterns of failure for the pN0, pN+/ECS- and, pN+/ECS+ groups showed overall recurrence rates of 19.8%, 34.2%, and 51.1% with regional failure rates of 11.5%, 19.2%, and 28.9%, respectively, and distant metastases rates of 3.3%, 8.2%, and 24.4%. CONCLUSIONS. ECS is the most significant predictor of both regional recurrence and development of distant metastasis accounting for decreased survival of patients with SCCOT in the current study. Therefore, intensive regional and systemic adjuvant therapy may be indicated for patients with ECS. Future studies should focus on identifying molecular mediators involved in ECS to determine targets for adjuvant therapies in this subset of patients.