ATM and neoplasm: Multivariate Cox model analysis showed that large tumor size (HR = 2.046, 95% CI: 1.116–3.752), positive lymph node (HR = 2.085, 95% CI: 1.096–3.966), downregulated expression of ATM (HR = 1.895, 95% CI: 1.026–3.501) and BRCA1 (HR = 2.163, 95% CI: 1.037–4.511) were independent poor prognostic factors for HNC patients in the KMUH cohort (Table 4).