PTEN and head and neck squamous cell carcinoma: In 2015, The Cancer Genome Atlas reported that the molecular landscape of HNSCC includes identified mutations in various oncogenes [PIK3CA (21%) and HRAS (4%)] and tumor suppressor genes [TP53 (72%), CDKN2A (22%), FBXW7 (5%), KMT2D (MLL2) (18%), and PTEN (2%)]12.