| Diagnostic Tests | Comments |
| Biochemical Studies |
|
| Serum chromogranin-A | The sensitivity and specificity depends on the cutoff value. In general sensitivity ranges from 50% - 100%. |
| Serum enolase* |
|
| Human chorionic gonadotropin* |
|
| Pancreatic polypeptide* |
|
| Insulin** |
|
| Gastrin** |
|
| Glucagon** |
|
| VIP** |
|
| Urinary excretion of 5-hydroxyindoleacetic acid (5-HIAA) | It has a sensitivity of over 90% and specificity of 90% for the carcinoid syndrome. |
| Radiologic Studies |
|
| Computed tomography (CT) scan | CT scans are non-invasive and readily available. Sensitivity for primary tumor ranges from 14% - 77%. Higher for metastatic lesion. |
| Magnetic resonance imaging (MRI) | MRI sensitivity for primary tumor is between 74% - 100%. It is the most sensitive method for detection of liver metastases. |
| Endoscopic ultrasonography | Useful for small pancreatic lesions and does not require contrast administration. It is operator dependent. |
| Somatostatin receptor scintigraphy | Most common technique for detecting gastropancreatic neuroendocrine tumours, with sensitivity of 67% - 100%. |
| Positron emissions tomography (PET) scan |
|
| Others |
|
| Arterial secretagogue injection | An invasive two-stage procedure. Sensitivity of 70% - 95%. |