Use of a somatostatin analog (SMS 201-995) in the glucagonoma syndrome.

A long-acting somatostatin analog, SMS 201-995, is now available to treat the hormonal manifestations of islet cell tumors. We report its use in a patient with a metastatic glucagonoma refractory to conventional therapy. This patient, who was severely disabled by the rash of necrolytic migratory erythema and brittle diabetes mellitus, allowed us to evaluate the therapeutic efficacy of SMS 201-995 and to gain insight into the origin of the rash. SMS 201-995 was administered subcutaneously (.05 mg twice a day). The rash improved markedly within 48 hours and was completely resolved within 1 week of treatment. Insulin requirements decreased from 90 U/day to zero during the first week of treatment. Corresponding to improvement in clinical symptoms circulating glucagon levels showed a marked decrease. There was no substantial change in plasma or urinary levels of zinc or in plasma amino acid levels. When SMS 201-995 was stopped, the rash recurred within 36 hours and it improved within 48 hours of readministration. The rash and diabetes have remained well controlled during 8 months of therapy but no change in tumor size has been seen on CT scan. The rapid changes in the rash related to the administration of SMS 201-995 indicate that the pathogenesis of necrolytic migratory erythema is probably due to circulating hyperglucagonemia or some other hormonal substance produced by the tumor.