Conversely, NSCLC-like LCNECs share some molecular alterations with non-NE-tumors, such as cyclin-dependent kinase inhibitor 2A (CDKN2A) deletion, TTF-1 amplifications, Kirsten rat sarcoma (KRAS), Kelch-like ECH-associated protein 1 (KEAP1), and liver kinase B1 (LKB1) mutations or alterations in other rat sarcoma (RAS) pathway genes. This evidence concerns the gene CDKN2A and sarcoma.