Clinical Background
Vasoactive intestinal polypeptide secreting tumor (VIPoma) is a rare endocrine tumor associated with profuse diarrhea.
Epidemiology
- Incidence - 1/10 million
- Age - median age of onset is 40-50 years
- Sex - equal gender distribution
- Occurrence - sporadic, although some occur in association with multiple endocrine neoplasia 1 (MEN 1)
Risk Factors
- Genetic - around 5% associated with MEN 1 syndrome
Pathophysiology
- Epithelial endocrine tumor of endodermal origin of which 50% are malignant
- Most tumors have been found in the body and tail of the pancreas and are unifocal
- Hormonal secretion is vasoactive intestinal polypeptide (VIP) which is the etiology of the symptoms
- VIP is an amino acid polypeptide that binds to intestinal epithelial cells and activates cellular adenylate cyclase and cyclic adenosine monophosphate (cAMP )
- Other tumors that can produce VIP include ganglioneuroblastoma, bronchogenic carcinoma, pheochromocytoma, medullary thyroid carcinoma and retroperitoneal histiocytoma
Clinical Presentation
- Verner-Morrison syndrome
- Watery diarrhea, hypokalemia and achlorhydria (WDHA triad)
- Dehydration and renal failure
- May occur as a result of profuse diarrhea
See Also
Diagnosis
Diagnosis
- Laboratory testing
- VIP level - elevated >75 pg/mL
- Histology
- Final confirmation of tumor type - special stains may be required
- Imaging studies
Differential Diagnosis
- Gastroenteritis
- Other peptide producing tumors - most commonly Zollinger-Ellison (gastrinoma)
- Laxative abuse
- Carcinoid tumor
- Pancreatic cancer
- Villous adenoma
Tests generally appear in the order most useful for common clinical situations
| Test name: Vasoactive Intestinal Peptide
|
| ARUP #: 0099435 |
| Methodology: Radioimmunoassay
|
| Use: Measure vasoactive intestinal peptide to determine likelihood of cancer |
| Limitations: |
| Follow-up:
|
| Test name: Immunohistochemistry Stain Offering
|
| ARUP #: Arup005 |
| Methodology: Immunohistochemistry
|
| Use: For fixed tissue samples, consultative services as well as immunohistochemical staining for CAM5.2 (LMW), PGP9.5 and synaptophysin are available |
Additional Tests Available
| Test name: Pancreatic Polypeptide
|
| ARUP #: 0099436 |
| Methodology: Radioimmunoassay
|
| Comments: |
References
General References
de Herder WW. Biochemistry of neuroendocrine tumours. Best Pract Res Clin Endocrinol Metab.
2007;
21(
1):
33-41.
Eriksson B, Oberg K, Stridsberg M. Tumor markers in neuroendocrine tumors. Digestion.
2000;
62 Suppl 1:
33-38.
Peng SY, Li JT, Liu YB, Fang HQ, Wu YL, Peng CH, Wang XB, Qian HR. Diagnosis and treatment of VIPoma in China: (case report and 31 cases review) diagnosis and treatment of VIPoma. Pancreas.
2004;
28(
1):
93-97.
Ram R, Natanzi N, Saadat P, Eliav D, Vadmal MS. Skin metastasis of pancreatic vasoactive intestinal polypeptide tumor: case report and review of the literature. Arch Dermatol.
2006;
142(
7):
946-947.
Smith SL, Branton SA, Avino AJ, Martin JK, Klingler PJ, Thompson GB, Grant CS, van Heerden JA. Vasoactive intestinal polypeptide secreting islet cell tumors: a 15-year experience and review of the literature. Surgery.
1998;
124(
6):
1050-1055.
Stephen AE, Hodin RA. Neuroendocrine tumors of the pancreas, excluding gastrinoma. Surg Oncol Clin N Am.
2006;
15(
3):
497-510.
Medical Reviewers
Meikle, A. Wayne, M.D. Medical Director, RIA and Endocrinology at ARUP Laboratories; Professor of Internal Medicine and Pathology, University of Utah
Comprehensive Review: July 2008
Last Update: July 2008
