背景胰腺神经内分泌肿瘤是起源于胰腺内分泌细胞的罕见肿瘤。生长抑素类似物可缓解因肿瘤激素过度分泌引起的相应症状,而且可延缓部分患者的疾病进展时间。链脲菌素单药或与阿霉素联合方案仍然是唯一已被批准用于治疗进展期胰腺神经内分泌肿瘤的化疗药物,然而其疗效并不满意。在临床前以及Ⅰ期和Ⅱ期临床试验中,多靶点酪氨酸激酶抑制剂舒尼替尼已显示出对于胰腺神经内分泌肿瘤的治疗活性。目的这是一项国际多中心、随机、双盲、安慰剂对照的Ⅲ期 Background Pancreatic neuroendocrine tumors are a rare tumor of pancreatic endocrine cells. Somatostatin analogues can relieve the symptoms caused by the over-secretion of tumor hormones, and can delay the progress of the disease in some patients. Streptozotocin alone or in combination with doxorubicin remains the only chemotherapeutic drug approved for the treatment of advanced pancreatic neuroendocrine tumors, however its efficacy is unsatisfactory. Sunitinib, a multi-targeted tyrosine kinase inhibitor, has shown therapeutic activity in pancreatic neuroendocrine tumors in preclinical and stage I and II clinical trials. Purpose This is an international multicenter, randomized, double-blind, placebo-controlled phase III