Patel Dhaval, Gara Sudheer Kumar, Ellis Ryan J, Boufraqech Myriem, Nilubol Naris, Millo Corina, Stratakis Constantine A, Kebebew Electron
Endocrine Oncology Branch, Clinical Research Center, National Cancer Institute, NIH, Building 10-CRC, Room 3-5840, Bethesda, MD, 20892, USA.
Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA.
World J Surg. 2016 Mar;40(3):683-9. doi: 10.1007/s00268-015-3242-y.
Patients with Cushing's Syndrome (CS) and Conn's Syndrome with bilateral adrenal masses pose a dilemma. Uptake of 18F-FDG by hyperfunctioning adrenal glands has not been previously reported and may help lateralize. The aim was to determine if 18F-FDG PET/CT scan could identify hyperfunctioning adrenal masses and determine a biological basis for uptake.
Patients with nonfunctional adenomas (n = 9), CS (n = 11), and Conn's syndrome (n = 4) underwent an 18F-FDG PET/CT scan with a volume of interest circumscribing each mass to obtain a maximal standardized uptake value (SUVmax). Thirty-two adrenal masses were analyzed. Genome-wide expression data from an independent cohort were analyzed in nonfunctioning adenomas (n = 20), Conn's syndrome (n = 29), and CS (n = 24) focusing on GLUT genes. For genes differentially expressed, immunohistochemistry was performed on tissue samples.
Cortisol-secreting masses (n = 16) had a higher average SUVmax of 5.9 compared to nonfunctioning masses (n = 11, average SUVmax 4.2) and aldosterone-hypersecreting masses (n = 5, average SUVmax 3.2) (p = 0.007). SUVmax cut-off of 5.33 had 50.0% sensitivity and 81.8% specificity in localizing a cortisol-secreting mass. GLUT3 expression was 2.19-fold higher in patients with CS compared to patients with nonfunctioning adenomas (p = 0.003) and 2.16-fold higher in patients with CS compared to Conn's syndrome (p = 0.006). GLUT3 immunohistochemistry showed 2.2-fold higher staining in CS tumor samples compared to nonfunctioning adenomas.
Differential 18F-FDG PET/CT uptake was observed in patients with nonfunctioning, aldosterone-hypersecreting, and cortisol-secreting masses. GLUT3 overexpression in cortisol-secreting tumor likely accounts for the differential uptake. Future larger cohort studies will need to be conducted to determine if 18F-FDG PET/CT uptake can lateralize cortisol-secreting adrenal masses in patients with bilateral adrenal masses.
库欣综合征（CS）和伴有双侧肾上腺肿块的原发性醛固酮增多症患者面临两难困境。此前尚未报道过功能亢进的肾上腺摄取18F-FDG的情况，而这可能有助于确定病变侧别。本研究旨在确定18F-FDG PET/CT扫描能否识别功能亢进的肾上腺肿块，并确定其摄取的生物学基础。
对9例无功能腺瘤患者、11例库欣综合征患者和4例原发性醛固酮增多症患者进行18F-FDG PET/CT扫描，在每个肿块周围设定感兴趣区以获得最大标准化摄取值（SUVmax）。共分析了32个肾上腺肿块。对来自一个独立队列的全基因组表达数据进行分析，该队列包括20例无功能腺瘤患者、29例原发性醛固酮增多症患者和24例库欣综合征患者，重点关注葡萄糖转运蛋白（GLUT）基因。对于差异表达的基因，在组织样本上进行免疫组织化学检测。
与无功能肿块（11例，平均SUVmax为4.2）和醛固酮分泌过多肿块（5例，平均SUVmax为3.2）相比，分泌皮质醇的肿块（16例）平均SUVmax更高，为5.9（p = 0.007）。SUVmax临界值为5.33时，定位分泌皮质醇肿块的灵敏度为50.0%，特异性为81.8%。与无功能腺瘤患者相比，库欣综合征患者的GLUT3表达高2.19倍（p = 0.003）；与原发性醛固酮增多症患者相比，库欣综合征患者的GLUT3表达高2.16倍（p = 0.006）。GLUT3免疫组织化学显示，库欣综合征肿瘤样本中的染色比无功能腺瘤高2.2倍。
在无功能、醛固酮分泌过多和分泌皮质醇的肿块患者中观察到18F-FDG PET/CT摄取存在差异。分泌皮质醇肿瘤中GLUT3的过表达可能是摄取差异的原因。未来需要进行更大规模的队列研究，以确定18F-FDG PET/CT摄取能否确定双侧肾上腺肿块患者中分泌皮质醇的肾上腺肿块的病变侧别。
