PIK3CD and small cell lung carcinoma: In the light of the fact that genetic alterations of PIK3CA (3% vs. 17%), PIK3R1 (2% vs. 1.8%), PIK3R2 (1.5% vs. 1.6%), AKT1 (0.5% vs. 2.1%), AKT2 (1.5% vs. 3%) and PTEN (8% vs. 6%) are observed in SCLC and NSCLC respectively (Table 1), the studies of treatment strategies of LC targeting PI3K/AKT pathway are in full swing.