Department of Radiology, Karolinska University Hospital, Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden. anders.sundin @ ki.se
Neuroendocrinology. 2012;96(4):261-71. doi: 10.1159/000342270. Epub 2012 Oct 12.
Gastroenteropancreatic neuroendocrine tumors (NETs), a heterogeneous family of tumors arising in a variety of anatomic sites, are generally well differentiated and often metastatic at diagnosis. Morphologic and functional imaging modalities have vastly improved the understanding and diagnosis of NETs. However, use of conventional imaging techniques and response criteria to assess treatment response is often complicated by the clinical course and cytostatic nature of oncologic treatments for NETs.
The means of therapeutic monitoring discussed in this review were based on a PubMed search of the medical literature and on the clinical expertise of the authors.
Morphology-based criteria for assessing tumor response in general oncology are presented, along with their limitations for assessing response in gastrointestinal and pancreatic NETs. Functional imaging and preliminary response criteria incorporating functional imaging are presented as possible solutions to monitoring treatment response in NETs.
Morphology-based criteria to assess tumor response have limitations for NETs, which are often slow growing and frequently demonstrate low response rates when based on conventional radiological criteria. Furthermore, many NET treatments do not induce cytotoxic effects despite demonstrated clinical benefit. Novel imaging techniques are available which have the potential to measure changes in tumor physiology and metabolism. These include (68)Ga-labelled somatostatin analogs for PET/CT-based monitoring of NET, molecular imaging with PET tracers that are not based on somatostatin receptor targeting, and functional MRI. These techniques should be explored as options for monitoring treatment in patients with NET.
胃肠胰神经内分泌肿瘤（NETs）是一类起源于多种解剖部位的异质性肿瘤，通常分化良好，在诊断时往往已经转移。形态学和功能影像学极大地提高了对 NETs 的理解和诊断。然而，由于 NETs 的临床病程和细胞毒性治疗的性质，使用常规成像技术和反应标准来评估治疗反应通常会变得复杂。
本综述中讨论的治疗监测方法是基于对PubMed 医学文献的搜索和作者的临床专业知识。
提出了一般肿瘤学中评估肿瘤反应的基于形态学的标准，以及它们在评估胃肠道和胰腺 NET 反应方面的局限性。提出了功能成像和包含功能成像的初步反应标准，作为监测 NET 治疗反应的可能解决方案。
基于形态学的标准来评估肿瘤反应对 NETs 有局限性，NETs 生长通常较慢，并且根据常规影像学标准，其反应率通常较低。此外，许多 NET 治疗方法尽管显示出临床获益，但不会引起细胞毒性作用。现有的新技术可以测量肿瘤生理学和代谢的变化。这些包括用于基于 PET/CT 的 NET 监测的 (68)Ga 标记的生长抑素类似物、不基于生长抑素受体靶向的 PET 示踪剂的分子成像以及功能 MRI。这些技术应作为监测 NET 患者治疗的选择进行探索。
