Infiltrative Recurrent Eccrine Spiradenoma of the Anterior Neck Treated Using Mohs Micrographic Surgery

Eccrine spiradenoma (ES) is a rare, usually benign adnexal tumour that may be sporadic or familial. The cell of origin has been debated and is thought to arise from the hair follicle.1 We describe a patient with Fitzpatrick skin type V who developed recurrent ES of the anterior neck treated using Mohs micrographic surgery (MMS). A 57-year-old woman with Fitzpatrick skin type V presented with a 5-month history of tender enlarging lesions on the anterior neck. She reported excision of a lesion at this site 14 years before. Examination revealed an 85-mm scar on the anterior neck. Firm tender subcutaneous papules and nodules were noted at two sites adjacent to the scar measuring 29 by 17 mm and 30 by 13 mm (Figure ​(Figure1).1). Skin biopsy showed a well-circumscribed tumor composed of small basaloid cells with interspersed vascular spaces and duct-like structures, typical of ES. Figure 1 Recurrent eccrine spiradenoma. Firm tender papules adjacent to scar from previous excision (central neck and left lateral neck sites). Ultrasound of the neck confirmed that the lesions were confined to the skin and subcutaneous tissue, with no apparent penetration of deep fascia and no lymphadenopathy. She underwent MMS of the two clinically apparent areas of recurrence. MMS histology confirmed tumor extension into the subcutaneous tissue (Figure ​(Figure2).2). At the left lateral neck site, tumor-negative MMS margins were achieved after four stages and eight blocks, with a defect size of 47 by 26 mm. At the central neck site, tumor-negative MMS margins were also achieved after four stages and eight blocks, with a defect size of 42 by 28 mm (Figure ​(Figure3).3). Both defects were repaired using primary direct closure. The intervening scar between the defects was also excised at closure. The histologic appearance of the debulked tissue from MMS at both sites confirmed appearances in keeping with ES, with cystic change noted at the left lateral site. No malignant changes were seen. Figure 2 (A) Photomicrograph of spiradenoma extending into fat, shown at ×10 magnification (hematoxylin and eosin staining). (B) The black rectangle, shown at ×40 magnification, illustrating the cellular morphology of spiradenoma. Figure 3 Final defects on anterior and left lateral neck. There was no evidence of recurrence 15 months after MMS.