Abstract
PURPOSE: Distant metastasis (DM) of head and neck squamous cell carcinoma (HNSCC) is not common but remains a substantial problem. Here, we evaluated factors predictive of long-term survival in HNSCC patients presenting with DM after initial definitive treatment. METHODS: The medical records of patients with HNSCC who underwent definitive treatment between 2006 and 2011 were reviewed. Univariate and multivariate analyses were performed to identify clinicopathological factors associated with long-term survival after DM. RESULTS: Of 779 HNSCC patients, 98 (12.6 %) had DM after completion of definitive treatment, with a median time to DM of 15 months (range 1-87 months). Overall survival (OS) rates at 1 and 2 years after DM were 43.1 and 20.5 %, respectively. In multivariate analysis, hypoalbuminemia (P < 0.001, hazard ratio [HR] 3.45, 95 % confidence interval [CI] 2.01-5.92), prior or simultaneous locoregional failure events (P < 0.001, HR 2.36, 95 % CI 1.47-3.79), multisite DM (P = 0.001, HR 2.30, 95 % CI 1.42-3.72), and no salvage treatment for DM (P = 0.003, HR 2.19, 95 % CI 1.32-3.64) were independent predictors of OS after the development of DM. Seventeen (18 %) patients survived >2 years. Patients who did not have any of these risk factors had the most favorable outcomes, with a 2-year survival of 100 %. CONCLUSIONS: In the absence of risk factors, long-term survival can be achieved despite the development of DM after definitive treatment.