ReviewImaging study findings in elastofibroma dorsi
Introduction
Elastofibroma is a benign tumor or pseudotumor whose distinctive histological features and anatomic location can be readily recognized by imaging studies. The appearance by magnetic resonance imaging (MRI) and computed tomography (CT) is often typical, obviating the need for a biopsy [1]. Ultrasonography and plain radiography may also contribute to the diagnosis. However, physicians should be aware of the clinical manifestations, as these are often virtually pathognomonic, so that imaging studies merely serve to confirm the diagnosis.
Section snippets
Histological features
As indicated in the initial description by Järvi and Saxén [2], elastofibromas exhibit a characteristic structure in which streaks of fatty tissue alternate with strands of fibrous tissue (Fig. 1). This structure reflects the genesis of elastofibromas, which involves overproduction of collagenous connective tissue alternating with deposition of fat [3], [4]. The hypertrophic fibrous tissue contains fibrillar material whose staining affinities are identical to those of elastin fibers
Epidemiology
Elastofibromas are slow-growing lesions that develop in a highly characteristic anatomic location. Their prevalence is relatively high among older individuals. Nagamine et al. [4] reported a study of 170 cases in the Okinawa area of Japan, whereas most of the other publications report single cases [5], [6], [7], [8], [9], [10], [11] or small series of two to five cases [12], [13], [14], [15], [16], [17]. The highly distinctive features of elastofibroma were documented consistently in all these
Clinical features and treatment
The lesions are asymptomatic in over 50% of the cases [4], [11], [19]. When symptoms are present, they are usually mild, consisting of a swelling, clunking of the scapula on moving the shoulder, or moderate pain; severe pain is uncommon [4], [19], [21], [23]. A wait-and-see approach is appropriate in patients with no symptoms. When the symptoms are sufficiently bothersome to warrant surgery, marginal resection is sufficient, as recurrences are exceedingly rare [17] and malignant transformation
Pathogenesis
The location of elastofibromas and their predominance among older individuals militate against a neoplastic mechanism and strongly suggest a reactive process in response to rubbing of the scapula against the ribs [3], [11]. The reactive process combines a hyperplastic response, degeneration of collagen fibers, and overproduction of immature elastic tissue derived from fibroblasts [23]. Genetic factors may also be involved, as high prevalences of elastofibroma have been noted in specific
Magnetic resonance imaging
MRI is undoubtedly the investigation of choice, as it clearly shows the alternating pattern of fibrous tissue and fatty tissue, as well as the highly characteristic location of the mass (Fig. 2). The margins may be sharp or indistinct [17] and the mass itself is heterogeneous. On T1-weighted and T2-weighted sequences, the fibrous tissue produces low-intensity signal nearly identical to that generated by the muscle. The low signal on T2 images is ascribable to the scarcity of cells and abundance
Computed tomography
The findings are the same as with MRI: the mass may have indistinct or sharp contours [13] and is composed of fibrous tissue having the same density as muscles alternating with streaks of tissue of fat density [1], [9], [10], [12], [21] (Fig. 4). After injection of an iodinated contrast agent, the density of the mass remains virtually unchanged [14].
CT is less sensitive than MRI for visualizing the streaks of fatty tissue, so that the elastofibroma may be seen as a nearly homogeneous mass whose
Ultrasonography
Ultrasonography shows an abnormal mass of tissue in a location typical for elastofibroma. Technological improvements have improved the ability of ultrasonography to visualize the typical layered structure. Typically, an alternating pattern of hyperechoic and hypoechoic lines that are roughly parallel to the chest wall is seen in all or part of the mass [12], [26] (Fig. 5).
Plain radiography
Although the value of plain radiography for the diagnosis of elastofibroma has been described as limited [21], the finding of a tissue mass that lifts the inferior pole of the scapula away from the ribs is highly suggestive. In addition, plain radiographs show that there are no bone abnormalities adjacent to the mass. In addition, high-quality plain radiographs may show linear streaks of tissue having the density of fat [10], [12] (Fig. 6).
Conclusion
The diagnosis of elastofibroma is readily established provided the physician is familiar with the typical features and seeks them routinely. A mass composed of alternating strands of fatty and fibrous tissue is pathognomonic if it is located at the inferior pole of the scapula. Thus, the definitive diagnosis can be made by MRI (the investigation of choice), CT, or even ultrasonography or plain radiography. A bilateral distribution is an additional argument in favor of elastofibroma.
The clinical
References (28)
- et al.
Elastofibroma and pre-elastofibroma a biopsy and autopsy study
Eur J Surg Oncol
(1996) - et al.
Pseudotumeurs des parties molles
Encycl Méd Chir, Radiodiagnostic–Neuroradiologie–Appareil locomoteur
(2003) - et al.
Elastofibroma dorsi
Acta Pathol Microbiol Scand
(1961) - et al.
Subclinical elastofibromas in the scapular region in an autopsy series
Acta Pathol Microbiol Scand
(1975) - et al.
Elastofibroma in Okinawa. A clinicopathologic study of 170 cases
Cancer
(1982) - et al.
Elastofibroma: chest wall pseudotumor
Radiology
(1986) - et al.
Case report 583
Skeletal Radiol
(1989) - et al.
MR appearance of bilateral periscapular elastofibromas
J Comput Assist Tomogr
(1989) - et al.
Elastofibroma dorsi: CT, MR and pathologic study in a new case
JBR-BTR
(1992) - et al.
Elastofibrome sous-scapulaire: diagnostic IRM
Rev Im Med
(1995)
Case report: elastofibroma dorsi: a pseudomalignant lesion
Clin Radiol
Elastofibroma in shoulder osteoarthritis
Clin Orthop
Aspect échographique de l'élastofibrome dorsal
J Radiol
Elastofibroma: MR and CT appearance with radiologic–pathologic correlation
Am J Roentgenol
Cited by (64)
Prevalence of elastofibroma dorsi on CT: Is it really an uncommon entity?
2019, Acta Orthopaedica et Traumatologica TurcicaElastofibroma dorsi: Clinical evaluation of 61 cases and review of the literature
2017, Acta Orthopaedica et Traumatologica TurcicaElastofibroma dorsi: A case report of extra-osseous uptake of <sup>99m</sup>Tc-HMDP
2015, Medecine NucleaireAn unusual cause of shoulder pain
2015, Indian Journal of RheumatologyDorsi elastofibroma. About 14 cases, and review of the literature
2014, Annales de Chirurgie Plastique Esthetique