POU2F3 and small cell lung carcinoma: Among first-line SCLC patients, there was numerically longer survival with the addition of ICB to chemotherapy in a non-NE immune-inflamed subset (SCLC-I) compared with NE subsets SCLC-A, driven by achaete-scute homologue 1 (ASCL1), and SCLC-N, driven by neurogenic differentiation factor 1 (NEUROD1); and another non-NE subset, SCLC-P, driven by POU class 2 homeobox 3 (POU2F3) (16).