For example, in another recent report that investigated the hotspot mutation of PIK3CA in 143 patients with CSCC [49], the frequencies of the E542K, E545K and H1047R PIK3CA mutations were 1.4% (2/143), 2.8% (4/143), and 0.7% (1/143), respectively. Here, PIK3CA is linked to skin squamous cell carcinoma.