Tomomi Nobashi, Presenter: Nothing to Disclose

Yuji Nakamoto MD, PhD, Abstract Co-Author: Nothing to Disclose

Takeshi Kubo MD, Abstract Co-Author: Nothing to Disclose

Koya Nakatani MD, PhD, Abstract Co-Author: Research Grant, Nihon Medi-Physics Co, Ltd

Sho Koyasu MD, Abstract Co-Author: Nothing to Disclose

Kaori Togashi MD, PhD, Abstract Co-Author: Research Grant, Bayer AG Research Grant, DAIICHI SANKYO Group Research Grant, Eisai Co, Ltd Research Grant, FUJIFILM Holdings Corporation Research Grant, Nihon Medi-Physics Co, Ltd Research Grant, Shimadzu Corporation Research Grant, Toshiba Corporation Research Grant, Covidien AG

PET/CT with 68Ga-DOTATOC is known to be useful for detecting neuroendocrine tumors expressing somatostatin receptors. Somatostatin receptors are also expressed on inflammatory cells, but clinical efficacy of DOTATOC-PET/CT (PET/CT) for sarcoidosis has not been fully investigated. The purpose of this study was to compare the detectability of PET/CT for active sarcoidosis, with that of conventional 67Ga-citrate scintigraphy (GS).

A total of 9 patients (M:F=5:4, median age: 66), who were diagnosed as sarcoidosis by biopsy or clinical and radiological criteria, and underwent both GS and PET/CT, were analyzed. A PET/CT scan was performed within a day after GS. In GS, planar for a whole body and available SPECT images were evaluated. All images were interpreted by two experienced nuclear physicians on consensus. For abnormal uptake in both scans, the number of involved areas was counted in evaluating lymph nodes, and the actual number of lesions was counted in evaluating extra-nodal lesions.

Overall, detectability was almost comparable between the two modalities in a patient-basis; however, PET/CT showed abnormal uptake in hilar and mediastinal nodes in 8 patients, while GS in 7 patients. In a lesion-based analysis, more lesions tended to be depicted by PET/CT. For lymph nodes, the numbers of involved areas on PET/CT and GS were 24 and 18, respectively. For extra-nodal lesions, the numbers of abnormal accumulation on PET/CT and GS were 4 and 2 in uvea, 4 and 0 in muscle, 1 and 1 in lung, and 2 and 2 in submandibular glands, respectively. Of 5 patients who had clinically active uveitis, 2 had diffuse abnormal uptake along eyeballs, which was clearly depicted by PET/CT. Abnormal uptake suggesting cardiac sarcoidosis was not observed in this population. One patient suspicious to have chronic inactive sarcoidosis was negative in both scans.

PET/CT with 68Ga-DOTATOC depicted more lesions than GS did. Especially, active uveitis was demonstrated clearly by PET/CT.

68Ga-DOTATOC PET/CT may have practical usefulness in the detection and monitoring of sarcoidosis activity.

Nobashi, T, Nakamoto, Y, Kubo, T, Nakatani, K, Koyasu, S, Togashi, K, Detectability of PET/CT with ⁶⁸Ga-DOTATOC in Sarcoidosis Patients.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14004875.html