Histopathologic image from<unk>  cell carcinoma in<unk>  <unk>  of breast. Hematoxylin and eosin stain.<unk>  <unk> , also known as intraductal carcinoma, is a pre-cancerous or non-invasive cancerous lesion of the breast.<unk>  is classified as Stage 0. It rarely produces symptoms or a breast lump one can feel, typically being detected through screening mammography. In<unk> , abnormal cells are found in the lining of one or more milk ducts in the breast. In<unk>  means "in place" and refers to the fact that the abnormal cells have not moved out of the mammary duct and into any of the surrounding tissues in the breast ("pre-cancerous" refers to the fact that it has not yet become an invasive cancer). In some cases,<unk>  may become invasive and spread to other tissues, but there is no way of determining which lesions will remain stable without treatment, and which will go on to become invasive.<unk>  encompasses a wide spectrum of diseases ranging from low-grade lesions that are not life-threatening to high-grade (i.e. potentially highly aggressive) lesions.<unk>  has been classified according to the architectural pattern of the cells (solid, cribriform, papillary, and micropapillary), tumor grade (high, intermediate, and low grade), and the presence or absence of comedo histology.<unk>  can be detected on mammograms by examining tiny specks of calcium known as microcalcifications. Since suspicious groups of microcalcifications can appear even in the absence of<unk> , a biopsy may be necessary for diagnosis. About 20–30% of those who do not receive treatment develop breast cancer. It is the most common type of pre-cancer in women. There is some disagreement on its status as a cancer; some bodies include<unk>  when calculating breast cancer statistics, while others do not.
Ductal carcinoma in situ
Basal cell adenoma
Extramammary Paget's disease
Inverted papilloma
Carcinoma in situ
Lymphomatoid papulosis
Squamous cell papilloma
Lobular carcinoma in situ