We recently described a subset of SCLC CDX lacking expression of ASCL1 or POU2F3 that instead expressed the neurogenic, basic-helix-loop-helix TF ATOH1, which could be co-expressed with NEUROD1. 12ATOH1 was expressed in 4 CDX models from 3 of 31 patients with SCLC (9.6%). This evidence concerns the gene POU2F3 and small cell lung carcinoma.