Clinical predictors for contralateral neck lymph node metastasis from unilateral squamous cell carcinoma in the oral cavity

The factors that predict contralateral (C-) lymph node metastasis (LNM) in patients with unilateral oral squamous cell carcinoma (SCC) were analyzed. One hundred and twenty-nine patients who had untreated SCC that originated from the lateral oral cavity, but not around the midline, were included. The impact of multiple clinicopathologic factors (sex, performance status, primary site, T-stage, number and level of ipsilateral LNM, growth type, histopathological grading, mode of invasion, extension across the midline, and systemic neoadjuvant/adjuvant chemotherapy) on time-to-C-LNM was assessed using the stepwise Cox proportional hazards model. The T-stage, number of ipsilateral LNM, and histopathological grading were independent and significant predictors for C-LNM. No C-LNM occurred in patients without ipsilateral LNM and in those with earlier cancers (T1 to T3) excepting tongue cancer. The results of this retrospective study suggested that patients with advanced tumors, multi-involvement of the ipsilateral neck nodes, or a higher degree of histopathological grading were at a higher risk for C-LNM.