Treatment Outcomes and Pattern of Failure in the Surgically Treated Squamous Cell Carcinoma of Floor of the Mouth

Lim, Young Chang; Song, Mee Hyun; Kim, Sung Huhn; Lee, Wook Jin; Lee, Hun Suk; Shin, Joong Wook; Choi, Eun Chang

Abstract

BACKGROUND AND OBJECTIVES
Squamous cell carcinoma involving the floor of the mouth remains one of the most aggressive neoplasms of the head and neck. Its propensity to invade the mandible and to involve the lymphatic beds of both necks often makes local and regional control exceedingly difficult. This study reports the oncologic results of the surgically treated squamous cell carcinoma of the floor of mouth. SUBJECTS AND METHOD: From July 1992 to September 2001, 27 previously untreated floor of the mouth squamous cell carcinoma patients were treated with surgery with or without postoperative radiotherapy at Severance Hospital. Survival rates and factors affecting survival were studied using standard statistical analysis to determine statistical significance. RESULTS: The 2 year and 3 year disease-specific free survival rate in early staged carcinomas (stage I and II) were 85% and 77%, respectively, and in advanced staged carcinomas, 75% and 60%, respectively. Significantly decreased survival was seen in the patients with positive pathologic lymph nodes (p=0.001). However, there was no statistical significance for the effects of cT stage (p=0.56), performance of mandibular resection (p=0.755), mandibular invasion (p=0.688), and positive margins (p=0.98) on survival. Thirty-three percent of patients had recurrence. Recurrence was highest at the primary site, followed by the neck, and these were the most common sites of treatment failure. Two cases (67%) of nodal recurrence occurred in the anterior lymphatic chain (level VI). Distant metastasis was noted in 7.4% of the patients. CONCLUSION: Treatment with radical surgery of primary lesions and elective neck dissection including the anterior neck lymphatic chains may improve survival of patients with squamous cell carcinoma of the floor of mouth.