KRAS and small cell lung carcinoma: Despite the genetic and histologic transformation to either SCLC or SCC representing a well-known biological mechanism of acquired resistance to targeted therapies in NSCLC [192,193], the evidence of trans-differentiation to SCLC in the context of acquired resistance to KRAS c.34G > T (p.G12C)-targeted therapies is scarce and limited to clinical case reports [190].