Walczak R, Kawalilak L, Griffin L
Department of Environmental and Radiological Health Sciences, Colorado State University, College of Veterinary Medicine and Biomedical Sciences, 300 West Drake Road, Fort Collins, CO, 80523, USA.
Pulse Veterinary Specialists and Emergency, #320, 450 Ordze Road, Sherwood Park, Alberta, T8A5K6, Canada.
J Small Anim Pract. 2022 Mar;63(3):227-233. doi: 10.1111/jsap.13446. Epub 2021 Nov 22.
Canine insulinomas are uncommon malignant functional pancreatic neuroendocrine tumours with a high metastatic rate. Diagnostic imaging aids with staging and surgical planning of these tumours; however, identification is unpredictable across modalities. High-grade human pancreatic neuroendocrine tumours display increased avidity on F-fluorodeoxyglucose positron emission tomography-CT.
Dogs with clinicopathologic findings consistent with pancreatic insulinoma were prospectively enrolled. Patients underwent F-fluorodeoxyglucose positron emission tomography-CT and CT angiography, followed by exploratory laparotomy.
Three patients met the inclusion criteria and had histologically confirmed insulinomas. Both metastatic lesions in patient 1 were mildly avid (SUV 2.79 and 3.01). In patient 2, the primary pancreatic insulinoma was minimally avid (SUV 2.16). The primary pancreatic lesion in patient 3 had similar avidity to normal pancreatic parenchyma (SUV 1.54) and was undetected on F-fluorodeoxyglucose positron emission tomography-CT. Insulinomas demonstrated variable attenuation and contrast enhancement patterns on CT angiography and certain lesions were more conspicuous than on F-fluorodeoxyglucose positron emission tomography-CT. Two metastatic lesions not visible on either imaging modality were discovered in patient 2 at surgery.
Canine insulinomas were inconsistently avid on F-fluorodeoxyglucose positron emission tomography-CT. This finding is likely attributable to the confounding clinicopathological features and multifaceted transformation of these tumours, in addition to the influence of variable tumour size, composition and vascularity. Unpredictable tumoural avidity limits the value of F-fluorodeoxyglucose positron emission tomography-CT for staging canine insulinomas.
犬胰岛素瘤是罕见的恶性功能性胰腺神经内分泌肿瘤，转移率高。诊断性影像学检查有助于这些肿瘤的分期和手术规划；然而，不同检查方式对其的识别具有不可预测性。高级别的人类胰腺神经内分泌肿瘤在氟脱氧葡萄糖正电子发射断层扫描-CT（F-fluorodeoxyglucose positron emission tomography-CT，FDG-PET-CT）上表现出更高的摄取。
前瞻性纳入临床病理表现符合胰腺胰岛素瘤的犬。患者接受FDG-PET-CT和CT血管造影，随后进行剖腹探查术。
3例患者符合纳入标准，组织学确诊为胰岛素瘤。患者1的两个转移灶摄取轻度增高（标准化摄取值分别为2.79和3.01）。患者2的原发性胰腺胰岛素瘤摄取最低（标准化摄取值为2.16）。患者3的原发性胰腺病变与正常胰腺实质摄取相似（标准化摄取值为1.54），在FDG-PET-CT上未被发现。胰岛素瘤在CT血管造影上表现出不同的衰减和对比增强模式，某些病变比在FDG-PET-CT上更明显。患者2在手术中发现两个在两种影像学检查中均不可见的转移灶。
犬胰岛素瘤在FDG-PET-CT上的摄取不一致。这一发现可能归因于这些肿瘤复杂的临床病理特征和多方面的转变，以及肿瘤大小、成分和血管的影响。肿瘤摄取的不可预测性限制了FDG-PET-CT在犬胰岛素瘤分期中的价值。
