Characteristics of 49 patients with liver metastases from gastrointestinal neuroendocrine tumor grade 1 and 2; AP: Alkaline phosphatase, CGA: Chromogranin A, 5HIAA: Urinary 5 hydroxy-indole acetate acid; ULN: Upper limit of normal; mets: Metastases; D-Pas: Duodeno-pancreas. This evidence concerns the gene CHGA and digestive system neuroendocrine tumor, grade 1/2.