The molecular classification of SCNEC encompasses four entities: (1) small cell lung cancer (SCLC)—a characterized achaete scute family b HLH transcription factor (ASCL1) immunopositivity apart from classic neuroendocrine markers, (2) SCLC-N characterized by NEUROD1 immunopositivity and somewhat weaker expression of neuroendocrine markers, (3) SCLC-P characterized by POU2F3 (POU domain class 2 transcription factor 3) immunopositivity and absence of classic neuroendocrine markers, (4) SCLC-I/inflamed with no defined marker [4]. Here, NEUROD1 is linked to small cell lung carcinoma.