POU2F3 and small cell lung carcinoma: This has led to the identification of several SCLC subtypes, including SCLC-A (ASCL1-positive), SCLC-N (NEUROD1-positive), SCLC-P (POU2F3-positive), and SCLC-Y (YAP1-positive) or SCLC-inflamed [5,6].