Gastroenteropancreatic neuroendocrine tumours - Modlin, I M; Oberg, K; Chung, D C; Jensen, R T; de Herder, W W; Thakker, R V; Caplin, M; Delle, F G; Kaltsas, G A; Krenning, E P; Moss, S F; Nilsson, O; Rindi, G; Salazar, R; Ruszniewski, P; Sundin, A (Lancet Oncol, 2008)