CHGA and pancreatic neuroendocrine tumor: Biomarkers include urine 5-hydroxyindoleacetic acid (5-HIAA), synaptophysin on biopsy, and serum chromogranin A. The imaging tests needed are a computed tomography (CT) scan, somatostatin-receptor scintigraphy (OctreoscanTM), endoscopic ultrasonography (mainly for duodenal and pancreatic NET), magnetic resonance imaging (MRI), or DOT A-TOC FDG/PET.