ASCL1 (p = 0.0016), BCL2 (p < 0.0001), CASP8 (p = 0.0030), CCNE1 (p = 0.0135), CDK1 (p = 0.0146), CDK2 (p = 0.0114), CDKN1A (p = 0.0107) and CDKN2A (p = 0.0002) showed lower expression in carcinoids compared to carcinomas. This evidence concerns the gene CDK2 and carcinoma.