Particularly, activating mutations of the catalytic subunit alpha (PIK3CA) of PI3 K lipid kinases family was associated with poor PFS in our cohort including a case of small‐cell lung cancer (SCLC) transformation, since activation of PI3 K/AKT/mTOR signaling pathway was not mutually exclusive with other carcinogenic driving mechanisms. Here, PIK3CA is linked to small cell lung carcinoma.