Islet 1 (Isl1) expression is a reliable marker for pancreatic endocrine tumors and their metastases - Schmitt, A M; Riniker, F; Anlauf, M; Schmid, S; Soltermann, A; Moch, H; Heitz, P U; Klöppel, G; Komminoth, P; Perren, A (Am J Surg Pathol, 2008)