Eccrine Spiradenoma Arising in the Breast Misdiagnosed as an Epidermal Inclusion Cyst

Abstract

Eccrine spiradenomas are rare, benign, cutaneous tumors that originate in the sweat glands. Eccrine spiradenomas in the breast are very rare and only a few cases have been reported. We report here on the case of a 47-year-old woman with superficial masses in the breast and these masses had gradually increased in size during follow-up. They were confirmed to be an eccrine spiradenoma on pathologic examination. There have been a few reports about the radiologic findings of eccrine spiradenomas of the breast. This is the first case of an eccrine spiradenoma in the breast that was characterized by multiple imaging modalities, including mammography, ultrasonography and MRI. The lesion in our patient was first diagnosed as an epidermal inclusion cyst based on the imaging findings and the mass's superficial location. Although the mammographic and ultrasonographic imaging findings of eccrine spiradenomas and epidermal inclusion cysts are similar, the MRI findings are different between epidermal inclusion cysts and eccrine spiradenomas. Eccrine spiradenomas should be considered in the differential diagnosis of cutaneous and subcutaneous lesions of the breast.

Ultrasonographic Features of Eccrine Spiradenoma

“…Recently, US has frequently been used for the evaluation of small soft tissue tumors. Although eccrine spiradenoma is classified as a cutaneous tumor originating from skin appendages, all cases in this study were mainly located in the subcutaneous layer with or without involvement of the dermal layer and were similar to those in previously published reports . This location was thought to be caused by the relatively strong and elastic nature of the dermal layer compared with that of the subcutaneous fat layer, as described by Jin et al There were also no extensions to the epidermis and muscular structures of the lesions.…”

“…Only a few reports of US or magnetic resonance imaging (MRI) characteristics of eccrine spiradenoma have been published. To the best of our knowledge, there have been 3 case reports regarding the US features and 6 case reports regarding the magnetic resonance imaging features . Therefore, the purpose of this retrospective series was to analyze and describe its US characteristics.…”

“…To the best of our knowledge, there have been 3 case reports regarding the US features 3-5 and 6 case reports regarding the magnetic resonance imaging features. 4,[6][7][8][9][10] Therefore, the purpose of this retrospective series was to analyze and describe its US characteristics.…”

Sonographic Characteristics of Apocrine Nodular Hidradenoma of the Skin

“…The use of sonography has been reported in hidradenoma as case reports with 1 or 2 cases . Mostly, these showed hidradenomas with the eccrine differentiation, and in most cases, the examinations were performed without following the guidelines and technical considerations for studying dermatologic lesions .…”

Basaloid Carcinoma of the Breast Mimicking Cutaneous Basaloid Neoplasms

“…33 Spiradenomas of the breast have occasionally been reported. [34][35][36] None of the cases in the breast literature involved the nipple. However, 1 case presented with skin ulceration and contained areas of malignant transformation to spiradenocarcinoma.…”