This essay will begin by the pathological classification of breast cancer. Breast cancer may arise from the epithelium of the duct system of the nipple (90%) or within the lobular epithelium (10%). Both lobular and ductal breast cancers are further divided into non-infiltrating (not penetrated the limiting basement membranes) and infiltrating (those that have penetrated the basement membrane) (Robbins amp. Kumar 1987.)Intraductal carcinoma represents about 5% of breast carcinomas. The neoplastic cells either assume a glandular pattern or piles up within the ducts as irregular excrescences. Continued proliferation eventually fills the ducts with compressed tumor cells. Clinically, they present as a palpable mass or as ropy cords within the breast. Eventually, the ducts are filled with cheesy necrotic tumor tissue. This cheesy necrotic tissue can be extruded with slight pressure when the ducts are transected (therefore called comedocarcinoma) About 70 % of these tumors become invasive.Intraductal papillary carcinoma occurs within ducts and is characterized by progressive epithelial atypicality, anaplasia, and invasion of the stroma of the stalk or periductal tissue. Usually, these lesions are large enough to be palpable and may be manifested by a serious, turbid or bloody discharge from the nipple (Robbins amp. Kumar 1987)Since these tumors can become invasive, appropriate therapy is warranted. Most centers practice both wide excisions with or without radiation therapy, but there are very few randomized studies, which have compared various therapies, and therefore, optimal treatment is not clear. At present, it may be recommended that in those patients who desire to preserve their breast, and in whom the condition appears to be localized, the management can include adequate surgery with pathologic evaluation and breastirradiation.