Paget's disease is characterized by weeping, eczematoid lesion of the nipple. There is often accompanying edema and inflammation. Biopsy of the nipple reveals malignant cells within the milk ducts. The lesion is invariably associated with an underlying invasive or in situ ductal carcinoma. The prognosis of Paget's disease is that of the underlying cancer. Standard treatment is mastectomy with axillary lymph node dissection only if invasive cancer is present.