Apart from PTEN, there were other genes which mutated at a lower percentage in our series, such as CKIT or CTNNB1 (both mutated at less than 1% and only in non-oropharyngeal HPV-negative tumours), have been reported in HNSCC in varied percentages30,38,40. The gene discussed is PTEN; the disease is head and neck squamous cell carcinoma.