Carcinoid TumorGastrointestinal NeoplasmsAppendiceal NeoplasmsMalignant Carcinoid SyndromeNeuronavigationCarcinoid Heart DiseaseAnatomy, RegionalIleal NeoplasmsNeurosurgical ProceduresSurgery, Computer-AssistedBronchial NeoplasmsSpinal Cord NeoplasmsBone NeoplasmsMonitoring, IntraoperativeBrain NeoplasmsHydroxyindoleacetic AcidIntestinal NeoplasmsChromograninsOctreotideNeuroendocrine TumorsReconstructive Surgical ProceduresChromogranin AACTH Syndrome, Ectopic