Elastofibroma dorsi incidentally detected by ^sup 18^F-FDG PET/CT imaging

• Published in: Annals of nuclear medicine Vol. 29; no. 5; p. 420
• Main Authors: Erhamamci, Seval, Reyhan, Mehmet, Nursal, Gul Nihal, Torun, Nese, Yapar, Ali Fuat, Findikcioglu, Alper, Canpolat, Tuba
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Nature B.V 01-06-2015
• ISSN: 0914-7187; 1864-6433
• DOI: 10.1007/s12149-015-0959-5

Elastofibroma dorsi (ED) is a rare pseudotumor of the soft tissues that can also show 18F-fluorodeoxyglucose (^sup 18^F-FDG) uptake on positron emission tomography combined with computed tomography (PET/CT) imaging. The aim of this retrospectively study was to describe the metabolic characteristics of ED incidentally detected by ^sup 18^F-FDG PET/CT imaging. Between November 2009 and August 2013 at our institution, 10,350 consecutive PET/CT examinations were retrospectively investigated. In 176 of these patients, ED was recorded as an incidental finding. Fifty-five of 176 patients also had follow-up scans after chemoradiotherapy. A total of 231 scans with ED in 176 patients were identified. To determine the metabolic activity of ED, the maximum standardized uptake value (SUV^sub max^) was calculated semiquantitatively. For measurement size of ED, the longest axis of transaxial CT images was used. Seven of the 176 patients underwent surgery due to suspected metastases and/or invasion of primary malignancy and/or symptoms or incidental during surgery. The prevalence of ED in our series was 1.7 %. The lesions were located in the subscapular region in all patients, except in one case with a lesion in the infrascapular region. A total of 419 ED lesions in 231 scan of 176 patients were evaluated. Mean ± SD SUV^sub max^ and long axis values for these 419 lesions were 2.31 ± 0.61 (range 1.0-4.30) and 56.78 ± 17.01 mm (range 19-112 mm), respectively. Of these 176 patients, 141 (80.1 %) had bilateral lesions and 35 (19.9 %) had unilateral lesions. There were statistically significant differences in the SUV^sub max^ and long axis values between the right and left side in the bilateral lesions (p = 0.001). No significant differences in the SUV^sub max^ and long axis values of the lesion were found between pre- and posttreatment in the patients with follow-up scans. Elastofibroma dorsi located in the scapular region is usually bilateral, asymmetric and with mild or moderate metabolic activity on PET/CT imaging. In addition, the metabolic activity and size of ED remained stable after chemoradiotherapy. Awareness of these metabolic characteristics of ED is important for preventing misinterpretation during ^sup 18^F-FDG PET/CT studies.