Virgolini I, Kurtaran A, Leimer M, Kaserer K, Peck-Radosavljevic M, Angelberger P, Hübsch P, Dvorak M, Valent P, Niederle B
Department of Nuclear Medicine, University of Vienna, Austria.
J Nucl Med. 1998 Sep;39(9):1575-9.
A major problem in patients with small endocrine tumors is the difficulty in localizing the primary tumor site. Many endocrine tumors possess larger amounts of high affinity vasoactive intestinal peptide (VIP) binding sites compared with normal tissue or blood cells. We used radiolabeled VIP to localize the tumor site in a patient with Verner-Morrison syndrome (VMS). Under octreotide therapy, the VIP levels had declined in this patient, but a tumor site could not be detected by conventional techniques or by radiolabeled octreotide. However, using 123I-VIP, the tumor was detectable in the pancreatic tail. Surgical resection of the tumor was followed by complete remission of the VMS. Expression of VIP binding sites in the tumor was confirmed by a radioreceptor assay and showed cross-competition between VIP and octreotide. The identity of the VIP binding site in the tumor was analyzed by Northern blotting and revealed the expression of somatostatin receptor subtype 3, which binds both somatostatin-14 and VIP with higher affinity than octreotide. Iodine-123-VIP scintigraphy would be an effective tracer to identity the tumor site in VMS patients.
小内分泌肿瘤患者的一个主要问题是难以定位原发肿瘤部位。与正常组织或血细胞相比，许多内分泌肿瘤具有大量高亲和力的血管活性肠肽（VIP）结合位点。我们使用放射性标记的VIP来定位一名患有韦纳-莫里森综合征（VMS）患者的肿瘤部位。在奥曲肽治疗下，该患者的VIP水平有所下降，但通过传统技术或放射性标记的奥曲肽均未检测到肿瘤部位。然而，使用123I-VIP，在胰尾可检测到肿瘤。手术切除肿瘤后，VMS完全缓解。通过放射受体分析证实了肿瘤中VIP结合位点的表达，并显示了VIP与奥曲肽之间的交叉竞争。通过Northern印迹分析肿瘤中VIP结合位点的身份，发现生长抑素受体亚型3的表达，该亚型与生长抑素-14和VIP的结合亲和力高于奥曲肽。碘-123-VIP闪烁扫描将是识别VMS患者肿瘤部位的有效示踪剂。
