The aim of this study is to determine hASH1 gene expression in the normal lung tissue and various types of lung tumors, to analyze whether its expression correlated with pulmonary neuroendocrine markers, and to explore the possibility of hASH1 as clinical pathological markers in the neuroendocrine tumors compared with previous neuroendocrine tumor markers. This evidence concerns the gene ASCL1 and neuroendocrine neoplasm.