Bilateral neck node metastasis: A predictor of isolated distant metastasis in patients with oral and oropharyngeal squamous cell carcinoma after primary curative surgery

Objectives/Hypothesis: The presence of distant metastasis after the initial treatment of oral and oropharyngeal squamous cell carcinoma (OOSCC) is often associated with a poor prognosis. The purpose of our study was to evaluate the frequency of isolated distant metastasis (IDM) that occurred without any local or regional failure, and to identify its predictive factors in patients who were surgically treated. Study Design: Retrospective chart review. Methods: We performed a retrospective analysis of 230 OOSCC patients who underwent surgical treatment of the primary lesion along with a simultaneous neck dissection between May 1992 and August 2004. We evaluated the frequency of IDMs without local or regional recurrences and the influence of different variables in their appearance. Results: The frequency of IDMs was 6%. Patients with oropharyngeal carcinoma had higher isolated distant failure compared with patients with oral cavity carcinoma (P <.05). In univariate analysis, the following conditions were significant predictors of IDM in patients with OOSCC: advanced local stage; clinical or pathologic positive neck node; the presence of more than two pathologic neck nodes; more than two bilateral pathologic nodal metastases; use of adjuvant radiotherapy; and advanced American Joint Committee on Cancer (AJCC) stage. However, in multivariate analysis, only the presence of pathologic positive lymph node, especially bilateral neck metastases, was an independent risk factor for the appearance of IDMs. Conclusions: The incidence of IDMs in patients with OOSCC is relatively low. These events were significantly associated with bilateral neck node metastases.