Table 5.
Peptide markers specific to the tumour site
| Site | Type | Laboratory tests required | Results expected |
| Gastric | I and II | CgA, gastrin | Raised |
| III | CgA, gastrin | Raised CgA, gastrin not raised | |
| Duodenal | CgA, gastrin, PP, urinary 5-HIAA, SOM | Raised CgA in 90% | |
| Consider MEN1 | |||
| Jejunal, ileal and proximal colon | CgA, urinary 5-HIAA, NKA | Raised CgA (>80%), U-5-HIAA (70%) and/or NKA (>80%); see text | |
| Proximal colon | CgA, urinary 5-HIAA, NKA, (PP) | Raised CgA (>80%), U-5-HIAA (70%) and/or NKA (>80%); see text | |
| Appendiceal | CgA, urinary 5-HIAA, NKA, (PP) | None raised unless metastatic | |
| Metastatic: markers as ileal | |||
| Goblet cell | CgA, urinary 5-HIAA, NKA, (PP) | None raised | |
| Rectal | CgA, CgB, PP, glucagon, HCG-β | Raised CgA (rarely); see text | |
| Raised CgB, PP, glucagon and/or HCG-β in some | |||
| Pancreatic | CgA | Raised CgA in metastatic tumours only | |
| Insulinoma | CgA, insulin, blood glucose, | Insulin inappropriate to glucose; see text | |
| C peptide or pro-insulin | Raised C peptide and pro-insulin | ||
| Gastrinoma | Gastrin | Raised gastrin; see text | |
| Glucagonoma | Glucagon, enteroglucagon | Raised glucagon | |
| VIPoma | VIP | Raised VIP | |
| Somatostatinoma | SOM | Raised SOM | |
| PPoma | PP | Raised PP | |
| MEN1 | CgA, gastrin, (calcium, PTH), insulin, glucagon, PP |
Items in parentheses may be helpful for diagnosis and monitoring in individual patients.
CgA, chromogranin A; CgB, chromogranin B; HGC-β, human chorionic gonadotrophin β; 5-HIAA, 5 hydroxyindoleacetic acid; NKA, neurokinin A; PP, pancreatic polypeptide; PTH, parathyroid hormone; SOM, somatostatin; VIPoma, vasoactive intestinal peptide-secreting tumour.