Non-functioning Pancreatic Neuroendocrine Tumors in MEN1: Somatostatin Analogs Versus NO Treatment

A.Background More than 90% of patients with multiple endocrine neoplasia type 1 (MEN1) develop multiple pancreatic neuroendocrine tumors (pNETs). These tumors are the most common cause for premature death in MEN1. While functioning pNETs must be treated to reduce or cure hormonal excess, the procedures for non-functioning pNETs are yet under discussion. Treatment ranges from watchful waiting to subtotal and total pancreatectomy. The latter may represent an "overtreatment", resulting in general complications and diabetic metabolic status. The effect of somatostatin analogues (SAs) has shown promising results with regard to progression of non-functioning duodeno-pancreatic NETs. Treatment with SAs is highly safe and effective, resulting in long-time suppression of tumor growth. B. Aim In this study of MEN1 patients with non-functioning pNETs, the benefits of somatostatin analogs" (SAs; group 1) compared to "no treatment" (group 2) will be analyzed with regard to progression (tumor growth; development of new \[functioning and non-functioning\] neuroendocrine tumors and regional/distant metastasis). C. Implementation Patients will either receive Somatostatin Analogs (SAs) or no treatment. The observation period will be 60 months. The increase of tumor size and development of new tumors or metastasis will be monitored.