[Clinical analysis of squamous cell carcinoma of the subglottis]

To investigate the clinical characteristics, pattern of lymph node metastasis, optimal management and relative prognostic factors of subglottic squamous cell carcinoma.

A retrospective review was conducted in 36 cases with subglottic squamous cell carcinoma from 1970 to 2005. TNM staging showed 6 patients with stage I, 9 stage II, 8 stage III and 13 stage IV (AJCC 2010). Eight of these 36 cases were treated with radiotherapy alone, 18 with surgery alone and 10 with surgery plus perioperative radiotherapy. The overall 5-year survival rate was estimated by the Kaplan-Meier method according to different clinical stages and treatments. Log-Rank analysis was used to identify the prognostic factors.

The overall 5-year survival rate was 58.2%, and 5-year survival rates were 66.7%, 66.7%, 62.5% and 30.8% for patients with stage I, II, III and IV, respectively, and the rates were 43.8%, 66.7% and 51.9% for radiotherapy alone, surgery alone, surgery plus perioperative radiotherapy, respectively. The 5-year survival rate of patients with stage I-III was significantly higher than that of patients with stage IV (χ(2) = 3.955, P < 0.05). Pathologically confirmed positive rate of cervical lymph node was 25.0% (9/36), and the positive cervical lymph nodes were mainly distributed in level VI, followed by level II. The 5-year survival rate of patients with negative cervical lymph node was significantly higher than that of patients with positive cervical lymph node (χ(2) = 6.466, P < 0.05).

The prognosis of subglottic squamous cell carcinoma was relatively poor. Total laryngectomy was the the main therapeutic management, and only part of the early cases could be treated with radiotherapy alone or partial laryngectomy. For locally advanced cases, the typical neck dissection including level II-IV and VI should be performed.