Extramammary Paget's disease of the breast: an unusual location with prognostic implications.

Extramammary Paget's disease is a neoplastic process of intraepidermal origin; its management and prognosis are very different from those of mammary Paget's disease. We present a case of extramammary Paget's disease located in the breast. This is an exceptional location, whose differential diagnosis is important because of its therapeutic and prognostic implications.