BACKGROUND:

Comedonic nevus is a rare benign tumor of the pilo-sebaceous unit which can occur in unusual topography such as the mammary region. It can have an isolated presentation or as part of the nevus comedonic syndrome. There is no treat-ment except for aesthetic reasons or secondary complications.

CLINICAL CASE:

A 45- year-old patient presented with a unilateral, linearly arranged dermatosis located on the trunk, affecting the axillary midline and the right mam-mary region. Characterized by a plaque of 4 x 1 cm, formed by open comedons. Starts from childhood and referred as asymptomatic, it has not presented changes during life. By dermoscopy 3mm diameter black keratin plugs were observed. An incisional biopsy was performed and sent to a histopathological study, which reported as comedonic nevus.

CONCLUSION:

Comedonic nevus is a rare tumor that can occur in the mammary region and must be recognized as a benign entity.