Patterns of lymph node metastasis and their influence on outcomes in patients with submandibular gland carcinoma

Abstract

Little is known about lymph node metastasis and the extent of neck dissection (ND) in patients with submandibular gland (SMG) carcinoma. We therefore evaluated the metastatic topography of neck lymph nodes in patients with SMG carcinoma and the influence of metastases on tumor recurrence and patient survival. The pattern of lymph node spread was analyzed in 64 patients with SMG carcinoma treated from January 1994 to January 2009. Disease-free survival (DFS), overall survival (OS), and distant metastasis-free survival (DMFS) were calculated, and the clinicopathological factors associated with each were analyzed. Positive pathological lymph nodes were detected in 31 (48.4%) patients and was found to correlate significantly with histologic grade (P<0.001) on univariate analysis. Eight patients (19.5%) had occult cervical metastases. The 5-year DFS, OS, and DMFS rates were 46.8, 56.2, and 58.5%, respectively, and 23 patients (35.9%) experienced systemic failure. Multivariate analyses revealed that T-classification (P=0.043) and N-classification (P=0.006) were significantly independent predictors of DFS, whereas only N-classification (P=0.049) was significantly associated with DMFS. Elective ND should be recommended for preoperatively suspected high-grade malignancy in SMG carcinoma. Patients with nodal metastasis should receive more effective therapy to hinder recurrence and distant metastasis.