Zosteriform configuration of multiple eccrine spiradenomas of the scalp

Eccrine spiradenoma (ES) is a benign adnexal tumor predominantly located in the head and neck regions. Multiple neoplasms located on the scalp have been reported but never with a zosteriform configuration on the first trigeminal area.

We describe an original case report of a 75-year-old Caucasian man presenting multiple subcutaneous blue and purple nodules disseminated on the first left trigeminal dermatome. All the nodules appeared gradually on a one-year period. Biopsy revealed a nodular adnexal tumor in the dermis without malignant eccrine spiradenoma (MES) transformation. The surgical procedure was performed in a manner to protect the galea aponeurotica in the upper half on the first left trigeminal area. The frontalis muscle was raised with the surgical specimen in the lower half of the first trigeminal area. A split-thickness skin graft was applied on the surgical defect. Histological examination revealed multilobular well-defined tumors located in the dermis.

The presence of multiple subcutaneous nodules in a trigeminal pattern should suggest a multiple localized zosteriform ES. The diagnosis is focused on clinical findings and the treatment is based on a large surgical excision. The histological examination is essential for not to fail a MES transformation.