REPORT OF A CASE
A 64-year-old black woman complained of a draining cyst on her right shoulder. Eighteen months previously, she had noted a tender, nondraining nodule on the shoulder. She subsequently underwent partial excision of the nodule. The wound never healed after surgery and continued to leak clear fluid. For the past 2 months, she noted a red nodule growing from the previous excision site that prompted her medical visit.Findings from her physical examination revealed a 1 × 1-cm, soft, irregular nodule on her right shoulder with a 4 ×4-mm protuberant, erythematous, moist papule on one edge (Fig 1). A small amount of clear fluid could be expressed from the lesion.An excisional biopsy was performed (Figs 2 through 4).What is your diagnosis?
Clear cell hidradenoma (CCH) (nodular hidradenoma).
Within the reticular dermis was a poorly circumscribed, nodular and cystic tumor, surrounded by a dense fibrocellular stroma. The solid portions of the tumor
Hampton MT, Sahn EE. Recurrent Draining Cyst on the Shoulder. Arch Dermatol. 1992;128(11):1535-1536. doi:10.1001/archderm.1992.01680210113018