However, AAT overexpression in cancer tissues is not an exclusive feature of CRC, since it has also been found in other types of cancers in different organs, including lung carcinomas [43], hepatocellular carcinomas [44], adenocarcinomas of the stomach [45,46], myeloid leukemia cells [47,48], brain tumors [49], carcinoid tumors, malignant melanomas, and schwannomas [50]. This evidence concerns the gene SERPINA1 and carcinoid tumor.