After analysing missense mutations and truncated mutations in oncogenes and tumour suppressors (results not shown), we have found that generally, in oncogenes, missense mutations are superior to truncated mutations but not in tumour suppressors, except from those more famous in HNSCC as CDKN2, FAT1 or PTEN. The gene discussed is PTEN; the disease is head and neck squamous cell carcinoma.