Four year treatment with a long acting somatostatin analogue in a patient with Verner-Morrison syndrome.

The case is described of a woman with a Verner-Morrison syndrome of extreme severity, caused by an occult VIPoma. Administration of SMS 201-995 (Sandoz) (SMS) at the dose of 150 and subsequently of 250 micrograms daily, decreased plasma levels of vasoactive intestinal polypeptide (VIP) from about 500 to 100 pg/ml (highest normal limit 60 pg/ml). This was associated with complete regression of the diarrhea and normalization of serum potassium levels and hence with the return of the patient to a fully normal life. After 36 months of clinical remission, watery diarrhea recurred together with elevation of VIP plasma levels and appearance of liver metastases. Laparotomic exploration led to the removal of a pancreatic VIPoma and its liver secondarisms, which was followed by a second remission. Reappearance of the symptoms and development of new liver metastases 8 months later required reinstitution of SMS therapy, which allowed once again to control the clinical picture. Anterior pituitary function, assessed by dynamic testing, was unaffected by chronic SMS administration with the exception of the stimulated growth hormone secretion that was inhibited. Glucose tolerance and insulin secretion remained normal during treatment. Glucose intolerance ensued after pancreatectomy and was not worsened by reintroduction of SMS. Treatment with SMS may allow long-lasting remission of Verner-Morrison syndrome associated to VIPoma, though it does not arrest the progression of the tumor.