TTC21B and small cell lung carcinoma: Two genes (PLEC, OBSCN) were mutated in CSCNET, SCLC and NET cell lines, one gene (TSC2) was mutated in CSCNET, panNET and NET cell lines, five genes (PLEC, VPS13A, OBSCN, KIAA1109 and PCNX) were mutated in CSCNET and SCLC, and six genes (KANK1, TSC2, NF1, DYNC1H1, PTEN and TTC21B) were mutated in CSCNET and panNET.