Sonographic features of steatocystoma simplex on the abdomen

Abstract

Dear Editor, Steatocystoma, originating from nevoid malformations of the pilosebaceous duct junction, is classified into steatocystoma multiplex (SCM) and steatocystoma simplex (SCS). The clinical manifestations of SCM differ from those of SCS: SCS is a single lesion that usually develops on the head or neck, while SCM develops on the trunk or extremities and is often inherited as an autosomal dominant trait. Brownstein described 30 cases of SCS in 1982. 1 Eleven lesions were present on the face, and the others developed on the scalp, neck, back, chest and limbs. Although several cases of SCS have been reported since then, ultrasonic analysis of SCS was described only once by Sunohara et al. 2 Here, we describe and discuss sonographic findings in a patient with SCS.A 41-year-old man presented to our hospital with a soft subcutaneous nodule under his umbilicus. The tumor had been growing slowly for more than 1 year. Physical examination revealed a soft, well-defined tumor measuring 1 cm in diameter with a smooth surface (Fig. 1a). The patient's family history was unremarkable, and we could not find any other skin tumors. Ultrasonographically, the nodule was well circumscribed and exhibited heteroechogenicity with the lateral shadows; it was "doughnut" shaped, with a small hypoechoic cystic lesion in the center (Fig. 1b). When we divided the resected specimen in half, the cyst contained the serous fluid and the viscous contents (Fig. 1c). Histopathological examination revealed an empty cyst attached to sebaceous glands in the dermis. The cyst wall was composed of several layers of squamous epithelium and hyalinized eosinophilic cuticle in the inner epithelium surface (Fig. 1d,e). The differential diagnosis included epidermal cyst, vellus hair cyst and SCS. Epidermal cyst was excluded by adhesion of sebaceous gland. We excluded vellus hair cyst because the cyst included no vellus hair. Based on these findings, we diagnosed the tumor as SCS.Some case reports of SCM have been accompanied by the ultrasonographic findings. 3-5 Mester et al. reported a case of SCM with sonographic examination. They stated the lesions were well defined and hypoechoic, and some of them contained fluid-debris levels (i.e. because the oily component was hypoechoic and the keratinous debris was isoechoic, there was a fluid-debris level between these two materials). 3 Park et al. examined 18 SCM lesions in five women. Fifteen of the lesions were hypoechoic and the others were isoechoic. 4 Wan et al. described ultrasonic features of SMC associated with a 59-year-old woman. The patient had multiple small nodules on the chest wall, axillae and forearm. On ultrasonography, the nodules were hypoechoic, mixed echoic and isoechoic lesions with well-circumscribed margins. 5 Previous SCM case reports have not described the aforementioned "doughnut"-shaped features (hypoechoic lesion in the center of an isoechoic cyst) present in our patient. Sunohara et al. described two cases of SCS in 2-year-old and 4-monthold girls. Ultrasonography revealed a well-d...

Coexistence of steatocystoma multiplex and hidradenitis suppurativa: Assessment of this unique association by means of ultrasonography and Color Doppler

“…A debris‐fluid level can be seen if both liquid and keratinous materials are present. A doughnut‐shaped appearance, namely hypoechoic lesion in the center of an isoechoic cyst, has also been described . In our cases, SM lesions appeared on ultrasonography as hypoechoic nodules with well‐defined hyperechoic borders and, in case of liquid content, posterior acoustic enhancement, in the absence of Color Doppler signal.…”

Ultrasonographic Spectrum of Cutaneous Cysts With Stratified Squamous Epithelium in Pediatric Dermatology: Pictorial Essay

“…The nonhereditary counterpart to steatocystoma multiplex is steatocystoma simplex, a solitary lesion that can be situated on the face, scalp, neck, axillae, chest, upper limbs, back, and lower limbs, with no family history, and an onset during adulthood. 23,24 There are few ultrasonographic reports of steatocystomas in the literature. The scarce reports found show them as well circumscribed nodules with heterogeneous echogenicity and lateral shadows.…”

“…A "doughnut" shape has been described, with a small central hypoechoic cystic lesion. 24 Other authors define them as well-defined cysts with internal echoes. 25 In our series we observed they are most frequently located in the subcutaneous tissue and less commonly in the dermis (Figure 8, A-C).…”

“…The differential diagnosis includes epidermal cyst, vellus hair cyst, and dermoid cyst. 24,25 In conclusion, ultrasound is an accurate and noninvasive tool to use in the diagnosis of cutaneous cysts, and usually to recognize them. However, in this revision, we described many of the multiple ultrasonographic faces of cutaneous CSSE in order to emphasize that they have a wide spectrum of US appearance and it is important to identify them to avoid misleading diagnoses and, hence, prevent erroneous treatments and procedures.…”

Sonographic Appearance of Steatocystoma: An Analysis of 14 Pathologically Confirmed Lesions

“…The ultrasonographic findings of steatocystomas have been reported in a limited number of studies ( 7 8 9 10 11 ), three of which reported mammographic and ultrasonographic findings of steatocystoma multiplex occurring in the breast. Park et al ( 10 ) reported the ultrasound findings of steatocystoma multiplex in four patients; sonographic findings revealed multiple well-circumscribed homogeneous lesions that either confined to the dermal layer or involved the subcutaneous fat.…”