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9 results found

Flat epithelial atypia

Flat epithelial atypia is an entity that comprises any columnar cell lesion with low-grade cytologic atypia. Terminology Flat epithelial atypia was introduced in the 3rd edition of WHO Classification of Breast Tumors in 2003, to substitute terms such as clinging carcinoma monomorphous type, at...

Columnar cell hyperplasia of the breast

Columnar cell hyperplasia is part of the spectrum of columnar cell lesions of the breast characterized by enlarged terminal ductal lobular units lined by stratified (more than two layers) columnar epithelium, cellular crowding or overlapping without atypia. It can also form tufts or mounds with...

Columnar cell change without atypia (breast)

Columnar cell change without atypia breast lesions are characterized by enlarged terminal ductal lobular units lined by columnar epithelial cells which substitute the normal cuboid epithelial layer.  They are also associated with prominent apical cytoplasmic snouts and intraluminal secretions. ...

CA 15-3

CA 15-3 is a tumor marker used in monitoring breast cancer. The test detects levels of MUC-1, a mucin protein in the blood. MUC-1 is thought to be important in the invasiveness and metastasization of cancer cells. Physiology Mucin-1 is a normal epithelial cellular glycoprotein localized to the...

Sentinel lymph node

The sentinel lymph nodes (SLNs) are defined as those lymph nodes that directly drain a malignancy, or alternatively can be considered as the first node(s) that a tumor metastasizes to. History and etymology "Sentinel node" as the initial draining node of a malignancy was first used in a paper ...


A fistula (plural: fistulae or fistulas) is an abnormal connection between two epithelial surfaces such as between hollow organs, skin or vessels. Conventionally, the name of a specific fistula type is a combination of the two organs. For discussions of specific fistulae please refer to individu...

Prostate specific antigen

Prostate specific antigen (PSA) is currently used as a tumor marker for prostate adenocarcinoma. PSA is a 33 kilodalton glycoprotein produced in prostate epithelial cells. Its normal physiologic role is as a liquefying agent for seminal fluid; only a tiny amount leaks into the blood, therefore ...


Metaplasia is a general pathology term that refers to the process when one cell type is replaced by another. It usually occurs in the context of a changed cellular environment to which the new cell type is better adapted 1. Examples include 2-5: Barrett esophagus: normal squamous epithelium rep...

Columnar alteration with prominent apical snouts and secretions

Columnar alteration with prominent apical snouts and secretions (CAPSS) is a pathological entity encountered when breast biopsies are done for investigation of punctate or amorphous calcifications. CAPSS involves the terminal ductal and lobular units (TDLU's). It is sometimes classified under t...

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