LETM1 and head and neck squamous cell carcinoma: To further substantiate the importance of high LETM1 expression in HNSCC progression, we analyzed disease-free survival and overall survival of 176 HNSCC cases using the Kaplan–Meier method and found that patients with high LETM1 expression had lower 5-year disease-free survival and overall survival than those with low LETM1 expression (P < 0.0001) (Figures 2(a)-2(b)).