Predictors for distant metastasis in head and neck cancer, with emphasis on age

PURPOSE: Distant metastasis (DM) in patients with head and neck squamous cell carcinoma (HNSCC) is uncommon, but strongly deteriorates prognosis. Controversy exists regarding age as a predictor for the presence and development of DM. The aim of this study was to investigate age and other predictors for DM in HNSCC patients. METHODS: From 1413 patients diagnosed with a primary HNSCC between 1999 and 2010 in a tertiary referral centre, patient, disease and pathological characteristics were extracted from patient files. Uni- and multivariable Cox regression analyses were performed to identify risk factors for DM as primary outcome. RESULTS: DM occurred in 131 (9.3%) patients, of which 27 (1.9%) were diagnosed simultaneously with the primary tumour, 27 (1.9%) were diagnosed synchronous, and 77 (5.4%) were diagnosed metachronous. The most common site of DM was lung (51.1%), followed by bone (19.1%) and liver (11.5%). Multivariable analysis identified male gender (HR = 1.95, 95% CI 1.23–3.10) hypopharyngeal tumours (HR = 3.28, 95% CI 1.75–6.14), advanced T-stage (HR = 1.61, 95% CI 1.09–2.38), poor differentiation grade (HR = 2.49, 95% CI 1.07–5.78), regional lymph node metastasis (HR = 5.35, 95% CI 3.25–8.79) and extranodal extension of regional lymph nodes metastasis (HR = 3.06, 95% CI 1.39–6.72) as independent prognostic factors for the presence or development of DM. No relation with age was found. CONCLUSION: Age is not related to the presence or development of DM. This study emphasizes the importance of screening for DM, especially in males, patients with hypopharyngeal tumours, advanced T-stage, histopathological poor differentiation grade, regional lymph node metastasis and extranodal extension.