GSTM1 present enhances CDDP detoxification of cells4 and the alleles A of XPC c.2815A>C22, G of XPD c.934G>A23, A of XPD c.2251A>C23, T of XPF c.2505T>C24, and C of TP53 c.215G>C29 SNVs induce greater DNA repair and less apoptosis of damaged cells, respectively, favoring higher survival of tumor cells and lower survival of HNSCC patients. The gene discussed is XPC; the disease is head and neck squamous cell carcinoma.