To date, several blood-based markers have been identified in association with SCLC, including neuron specific enolase (NSE), Progastrin-releasing peptide (ProGRP), chromogranin A (CgA) and pro-opiomelanocortin (POMC) [13,14,15,16,17,18,19]. This evidence concerns the gene ENO2 and small cell lung carcinoma.