Predictive factors for simultaneous distant metastasis in head and neck cancer patients during the diagnostic work-up

Abstract
Introduction The incidence of distant metastasis (DM) in patients affected by head and neck squamous cell carcinoma (HNSCC) is relatively low, and multiple risk factors were described for the development of distant metastasis. Materials and methods Retrospective study of patients diagnosed with a HNSCC between July 2016 and July 2020 in a tertiary university hospital. Results Five-Hundred and sixty-nine patients meet inclusion criteria. In the univariate analysis we found a statistical correlation in those patients affected by a hypopharyngeal tumour (p = < 0.0001), patients older than 60 years old (p = 0.01), advanced T stage (p = < 0.0001), a proven positive lymph node (p = 0.02), poorly differentiated tumour (p = < 0.0001), patients with 3 or more positive lymph nodes (p = 0.0001), with ECS (p = 0.0001) and a second primary tumour (p = 0.03). However, according to those results from our multivariable analysis, the factor related to an increased or higher chance to detect a DM during the diagnosis work-up were the presence of a hypopharyngeal primary tumor with a hazard ratio (HR) of 1.14, p = < 0.0001, advanced T stage (T3-T4) with a HR of 1.21, p = 0.001, poorly differentiated tumor with a HR of 1.04, p = < 0.0001, have proven positive lymph node with a HR of 1.03, p = 0.04, have more than three positive lymph node metastases with a HR of 1.25, p = 0.003, the presence of ECS with a HR of 1.40, p = 0.002, and have a second primary tumor with a HR of 1.05, p = 0.01. Conclusion According to the present study, factors such as hypopharyngeal tumours, advanced T-stage, poor differentiation grade, have more than three positive lymph nodes, ECS and have a second primary tumour should be considered as high-risk indicators for screening. Based on these results, the authors recommend considered an extensive diagnostic work-up in all patients with a high risk of DM development.