Track

Case Reports

Abstract

A 44-year-old man with recurrent complex anal fistulas presented for fistulotomy and excision of an indurated perianal mass. Over eight years, he had undergone multiple fistulotomies, catheter placements, and rectal advancement flaps, with persistent disease. Histopathology revealed granulation tissue, as expected in chronic fistulas, along with an epidermal proliferation of basaloid cells forming anastomosing strands in a fibrovascular stroma containing luminal structures. These features are consistent with eccrine syringofibroadenoma (ESFA), a rare benign eccrine tumor. Given ESFA’s benign nature but potential association with malignancy, complete excision is recommended. Fewer than 100 cases have been reported, including multiple ESFAs associated with hidrotic ectodermal dysplasia, as well as unilateral linear, solitary, and reactive forms. Although solitary ESFA typically presents in older patients on the extremities, reactive ESFA has no specific age or site predilection and likely arises in any setting of chronic inflammation. It has been reported in diabetic ulcers, ostomies and burn scars. This is the second reported case of perianal ESFA and the first associated with anal fistulas. The other case followed deep bacterial perianal infection in a young male, with trauma-induced eccrine duct remodeling proposed as the pathogenesis. Notably, ESFA was present in our patient’s earlier excisions but was unrecognized. The presence of a persistent mass and recurrent complex disease could have raised concern for an underlying neoplastic process. General pathologists should be aware of this diagnosis, given the diverse settings it develops in and the possibility that reactive ESFA may be more common than we think.