Many mutations have been discovered in primary SCLC, which include mutations in the retinoblastoma gene (RB), the rge myc proto-oncogene family, the phosphatase and tensin homolog gene (PTEN), and the fibroblast growth factor 1 receptor gene (FGFR1) [20,21,22,23]. The gene discussed is FGFR1; the disease is small cell lung carcinoma.