Functional Characterization of Adrenal Lesions Using [123I]IMTO-SPECT/CT

• Published in: The journal of clinical endocrinology and metabolism 2013-04, Vol.98 (4), p.1508-1518
• Main Authors: Hahner, Stefanie, Kreissl, Michael C, Fassnacht, Martin, Haenscheid, Heribert, Bock, Stefanie, Verburg, Frederik A, Knoedler, Pascal, Lang, Katharina, Reiners, Christoph, Buck, Andreas K, Allolio, Bruno, Schirbel, Andreas
• Format: Article
• Language: English
• Subjects: Adolescent; Adrenal Gland Neoplasms - diagnostic imaging; Adrenal Gland Neoplasms - epidemiology; Adrenal Gland Neoplasms - physiopathology; Adult; Aged; Aged, 80 and over; Biological and medical sciences; Carcinoma - diagnostic imaging; Carcinoma - epidemiology; Carcinoma - physiopathology; Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Endocrinopathies; Etomidate - adverse effects; Etomidate - analogs & derivatives; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Humans; Iodine Radioisotopes - adverse effects; Male; Medical sciences; Middle Aged; Multimodal Imaging - adverse effects; Multimodal Imaging - methods; Positron-Emission Tomography; Sensitivity and Specificity; Tomography, X-Ray Computed; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vertebrates: endocrinology; Whole Body Imaging; Young Adult
• ISSN: 0021-972X; 1945-7197
• DOI: 10.1210/jc.2012-3045

Context: Adrenal tumors are highly prevalent and represent a wide range of different pathological entities. Conventional imaging often provides only limited information on the origin of these lesions. Novel specific imaging methods are, therefore, of great clinical interest. Objective: We evaluated [123I]iodometomidate ([123I]IMTO) imaging for noninvasive characterization of adrenal masses. Design/Setting: This was a prospective monocentric diagnostic study in a tertiary care center. Patients and Intervention: A total of 51 patients with an adrenal lesion underwent [123I]IMTO imaging after injection of 185 MBq of [123I]IMTO. Sequential planar whole-body scans until 24 hours postinjection and single photon emission computed tomography (SPECT)/computed tomography imaging 4 to 6 hours postinjection were performed. Main Outcome Measure: Sensitivity and specificity of [123I]IMTO imaging for the noninvasive characterization of adrenal lesions were measured. Results: Adrenocortical tissue showed high and specific tracer uptake with a short investigation time and low radiation exposure. Qualitative analysis of SPECT/computed tomography data resulted in a sensitivity of 89% and a specificity of 85% for differentiating adrenocortical tumors from lesions of nonadrenocortical origin. Receiver-operating characteristic analysis of semiquantitative data revealed a sensitivity of 83% and a specificity of 86% for identification of adrenocortical lesions at a cutoff value of tumor to liver ratio of 1.3. Conclusions: [123I]IMTO is a highly specific radiotracer for imaging of adrenocortical tissue with a short investigation time and low radiation exposure. Because of the general availability of SPECT technology, [123I]IMTO scintigraphy has the potential to become a widely used tool to noninvasively characterize the biology of adrenal lesions.