The histology of the endobronchial biopsy demonstrated morphological features of SCLC, presenting small‐sized cells with a high nuclear‐to‐cytoplasmic ratio, nuclear molding, and frequent single‐cell apoptosis (CK7+, NCAM+, SYP−, Chromogranin−) (Fig. 1A, left, and data not shown). Here, KRT7 is linked to small cell lung carcinoma.