Multiple malignant eccrine poroma and a linear epidermal nevus

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Epidermal nevi are congenital skin conditions characterized by benign growths.
• Adnexal tumors originate from hair follicles, sebaceous glands, or sweat glands.
• The co-occurrence of these conditions is rare, with limited documented cases.

Observation:

• A 68-year-old woman presented with three reddish nodules on a linear epidermal nevus.
• The lesions were located on her right arm.
• Surgical resection was performed for both the nodules and the linear lesion.

Findings:

• Histopathological examination confirmed two nodules as eccrine porocarcinoma, a rare adnexal malignancy.
• The third nodule was identified as eccrine poroepithelioma, a benign adnexal tumor.
• The underlying linear lesion was confirmed to be an epidermal nevus.

Implications:

• This case represents the first documented instance of adnexal tumors arising within an epidermal nevus.
• Highlights the importance of vigilant monitoring and histopathological evaluation of lesions within epidermal nevi.
• Suggests a potential, albeit rare, neoplastic transformation pathway within epidermal nevi.