PIK3CA and head and neck squamous cell carcinoma: In HNSCC, both human papillomavirus (HPV)‐positive and HPV‐negative tumors show frequent direct activation of Akt, or indirect activation via the phosphoinositide 3‐kinase (PI3K) pathway, which serves as an upstream activator of Akt (Agrawal et al., 2011; Lawrence et al., 2015; Stransky et al., 2011).