ABSTRACT
OBJECTIVES: To examine the prognostic influence of hyoid bone invasion in advanced base of tongue squamous cell carcinoma treated with chemoradiation. METHODS: We retrospectively reviewed pre-treatment imaging (CT/MRI) for the presence or absence of hyoid bone invasion in patients with advanced (clinical T3 or T4a stage) base of tongue squamous cell carcinoma treated with chemoradiation from January 2001 to January 2011. We compared patients with hyoid bone invasion to those without based on the following metrics: 1-, 2- and 5-year locoregional recurrence-free survival, disease-free survival, disease-specific survival and overall survival. RESULTS: Eleven of thirty-seven patients had hyoid invasion present on pre-treatment imaging. Average follow-up was 45 months. Patients with hyoid bone invasion were found to have lower percentages in all survival metrics measured compared to patients without, respectively, with statistical significance achieved in the following: 2-year locoregional recurrence-free survival: 36.4% versus 86.4% (P = 0.006), 5-year locoregional recurrence-free survival: 12.5% versus 63.6% (P = 0.05), 2-year disease-free survival: 36.4% versus 77.3% (P = 0.05), 5-year disease-free survival: 12.5% versus 63.3% (P = 0.05) and the Kaplan-Meier curve for locoregional recurrence-free survival (P = 0.0075). CONCLUSIONS: Hyoid bone invasion by base of tongue squamous cell carcinoma may indicate a poorer prognosis despite treatment. Hyoid bone invasion may be a possible indication for intensification of treatment and/or may indicate a necessity for increasing the degree of post-treatment surveillance monitoring and imaging.
