Case report: elastofibroma dorsi: a pseudomalignant lesion

Imaging study findings in elastofibroma dorsi

Elastofibroma dorsi is a tumor or pseudotumor typically located under the tip of the scapula. It is far from uncommon in older individuals. The mass contains both fibrous tissue and fatty tissue. Imaging studies can provide the definite diagnosis in many cases. Computed tomography (CT) and magnetic resonance imaging (MRI) are particularly effective, as they visualize the characteristic layered pattern of fatty tissue (low-density by CT, high-signal on T1 images and intermediate signal on T2 images by MRI) and fibrous tissue (similar to muscle in terms of density by CT and signal intensity by MRI). To a lesser extent, plain radiographs and ultrasonography identify a number of suggestive features (location and layered structure). When the lesion exhibits typical imaging features and produces no symptoms, as is usually the case, further investigations are probably unnecessary.

Sonographic detection of elastofibroma dorsi

We describe the case of a 78-year-old man with a large elastofibroma deep to his scapula that was inconspicuous on MRI examination with his arm at his side in neutral position. The mass was not detected sonographically until the patient abducted his arm, allowing the elastofibroma to emerge from under the scapula. The diagnosis of elastofibroma was suggested by the typical sonographic appearance of a hypoechoic mass with interspersed linear echogenicity, resembling muscle. The mass was excised, and the diagnosis was confirmed on histopathologic examination.

Atypical appearance of elastofibroma dorsi on MRI: case reports and review of the literature

Three patients with histologically proven elastofibroma dorsi underwent MRI, using T1-weighted, T2-weighted, STIR (short inversion time inversion recovery), and contrast-enhanced SE sequences. All lesions typically displayed low signal intensity masses interspersed with areas of high signal intensity on T1- and T2-weighted SE images. Contrary to prior reports, two patients showed marked enhancement of the mass after administration of Gd-DTPA. Although the characteristic signal intensity on conventional T1- and T2-weighted images may lead to the early diagnosis of this rare tumor, radiologists should be aware that marked contrast enhancement may be representative in elastofibroma dorsi.

Elastofibroma dorsi: MR and CT findings

Elastofibroma dorsi is a benign, pseudotumoral soft tissue lesion of the periscapular area. The characteristical findings in magnetic resonance images and computed tomography usually allow the diagnosis and prevent radical surgery. We report the MR and CT findings of elastofibroma dorsi in four women presenting as an elongated soft tissue mass intermingled with fat, between the ribs and the serratus muscle, deep to the inferior angle of the scapula.