Department of Radiology, University of Kentucky Chandler Medical Center, 800 Rose Street, Lexington, KY 40536, USA.
Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, University of Kentucky Chandler Medical Center, 800 Rose St. HX315E, Lexington, KY, USA.
Clin Imaging. 2021 Jul;75:27-29. doi: 10.1016/j.clinimag.2021.01.010. Epub 2021 Jan 13.
Iatrogenic Cushing's syndrome has very well-known stigmata on physical examination but can pose a diagnostic challenge when it rarely presents radiologically. We present a classic albeit rarely encountered imaging appearance of Iatrogenic Cushing's on F-FDG-PET/CT, with diffuse subcutaneous white adipose proliferation and metabolic activation in a 7-year old patient one-month after starting a high dose steroid regimen for lymphoma. There was an extreme shift in the expected FDG biodistribution with dominant localization to the subcutaneous adipose tissue. This metabolic shift led to sub-threshold visceral biodistribution, rendering the scan non-diagnostic with regards to assessment of oncologic response. Aside from detailing the characteristic imaging findings of Iatrogenic Cushing's and its clinical importance, we discuss the physiologic basis of this imaging pattern and the rarer differential diagnosis to consider when this pattern of uptake is encountered on F-FDG-PET/CT.
医源性库欣综合征在体格检查上具有非常明显的特征，但当它很少表现为影像学特征时，诊断可能具有挑战性。我们展示了一个经典但罕见的医源性库欣综合征在 F-FDG-PET/CT 上的影像学表现，在一个 7 岁的患者开始大剂量类固醇治疗淋巴瘤一个月后，表现为弥漫性皮下白色脂肪增生和代谢激活。FDG 的生物分布发生了极端变化，主要定位于皮下脂肪组织。这种代谢转移导致内脏生物分布低于阈值，使得扫描无法用于评估肿瘤反应。除了详细描述医源性库欣综合征的特征性影像学表现及其临床重要性外，我们还讨论了这种影像学模式的生理学基础，以及在 F-FDG-PET/CT 上遇到这种摄取模式时需要考虑的更罕见的鉴别诊断。
