A Case of Scapular Hidradenoma Treated as a Keloid

Hidradenomas are relatively rare benign tumors in the dermis that differentiate into eccrine or apocrine sweat glands. They often present as round or oval nodules and vary in color. Generally, they occur in the head and neck region. Keloid scars are often red, elevated lesions that are caused by chronic inflammation in the reticular dermis. These scars demonstrate a preference for high skin-tension sites, including the scapular region. Herein, we describe a case of a dark red hidradenoma on the scapular region with a high incidence of acne surrounding the lesion area that was initially diagnosed as an acne-initiated keloid. However, local steroid injection did not cure the lesion. After excision, histopathology revealed typical findings for hidradenoma, namely mucinous, polygonal, and clear cell composition. In some cases, as presented it may be challenging for clinicians to differentiate between hidradenoma and keloid due to the similar clinical features. Thus, hidradenoma should be taken in consideration as a differential diagnosis when encountering steroid-refractory keloid-like lesions. Moreover, early biopsy or surgical resection should be considered.