Octreotide treatment for a malignant islet cell tumor with variable hormone secretion: case report.

It is well known that an islet cell tumor can secrete multiple hormones depending on its cell type. We report the case of a 70-year-old woman who initially presented with peptic ulcer symptoms, an elevated serum gastrin level, and multiple liver tumors. Liver biopsy and distal pancreatectomy were performed, and the pathological diagnosis was malignant islet cell tumor. Additionally, the immunohistochemical staining revealed scattered positivity for gastrin, and then also positivity for insulin 14 months later. A subsequent hypoglycemic episode and elevated serum gastrin and insulin levels suggested that the disease had developed into a condition of multiple hormone secretion. The plasma gastrin and insulin levels decreased from 584 pg/ml and 90.8 microIU/ml to 49.1 pg/ml and 20.9 microIU/ml, respectively, 5 days after treatment with subcutaneous octreotide 100 micrograms every 6 to 8 hours. In addition, follow-up computed tomography showed shrinkage of the metastatic liver tumors. In conclusion, we found a case of malignant islet cell tumor with variable hormone secretion which could be effectively controlled with octreotide.