Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.

318 results found
Article

Glial fibrillary acid protein (GFAP)

Glial fibrillary acid protein (GFAP) is a commonly used target for immunohistochemistry and is positive in many glial cells and tumors of glial origin. GFAP is the building block for intermediate filaments which are abundant in the cytoplasms particularly of astrocytes.  Related pathology Alex...
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Neoplasm

Neoplasms, also known as tumors, are pathological masses, caused by cells abnormally proliferating and/or not appropriately dying. Neoplasms may be either benign or malignant. Malignant neoplasms are synonymous with cancers. Benign neoplasms clear origin (unless very large) slow growth  usua...
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Eburnation

Eburnation describes the appearance of bone following a degenerative process in which subchondral or otherwise exposed bone acquires a non-anatomical sclerotic, microimpacted, and "polished" articular surface. This phenomenon typically arises in one of two situations: hypertrophic non-union of...
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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...
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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 ...
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Myocardial fiber disarray

Myocardial disarray, myocardial fiber disarray or cardiac myocyte disarray refers to bizarre disorganization and texture of cardiac myocyte bundles, individual cardiomyocytes and contractile elements within the sarcomeres. It is an important histological feature of hypertrophic cardiomyopathy wh...
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CD34

CD34 or hematopoietic progenitor cell antigen CD34 is an intercellular adhesion protein and cell surface glycoprotein and a frequently used marker of hematopoietic progenitor cells and endothelial cells. It is also expressed by many other non-hematopoietic cell types including multipotent mesenc...
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Desmin

Desmin is a muscle-specific protein. It is the main intermediate filament protein and a key component in the cytoskeletal network of muscle cells e.g. in the myocardium, where it is ampler than in skeletal muscle or smooth muscle. It interacts with other proteins to support the myofibrils at the...
Article

Selenium

Selenium (chemical symbol Se) is one of the trace elements. It has a vital role in the metabolism of the thyroid hormones and for the functioning of several important enzymes. Chemistry Basic chemistry Selenium has the atomic number 34 with an atomic weight of 78.96 g/mol. It is a non-metal a...
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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...
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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. ...
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Granuloma

Granulomas are organized conglomerates of histiocytes, a specialized white blood cell 1. They form by the process of granulomatous inflammation, which is a specific type of chronic inflammation that occurs following cellular injury as a response to the mediators that are released. A broad range ...
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BRAF

BRAF (B-Raf proto-oncogene serine/threonine-protein kinase) is a proto-oncogene, encoding for a serine/threonine protein kinase. Mutations of BRAF are the most common alteration of the RAS/MAPK pathway and these have been identified in a variety of tumors and congenital syndromes including 1-5: ...
Article

Staghorn pattern of vascularity

The staghorn pattern of vascularity is a pathological term describing a pattern of vascularity seen on low-power light microscopy. It is defined by multiple thin-walled, sharply-branched and jagged vessels having an "antler-like" or "staghorn-like" appearance 1. It is classically described with...
Article

KRAS mutation

KRAS (shortened name for the gene Kirsten RAt Sarcoma viral oncogene homolog) mutations are associated in a number of malignancies including:  certain adenocarcinomas of the lung colorectal carcinoma 1 pancreatic ductal adenocarcinoma Several germline KRAS mutations have also been found to b...
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Eosinophil

Eosinophils, also less commonly known as acidophils, are myeloid granulocytes and form one of the main types of white blood cells. Their counts are routinely measured as part of a full blood count. They have important roles in fighting parasitic infections, but are increasingly recognized as hav...
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Platelets

Platelets, also known as thrombocytes, are an essential constituent of the cellular component of blood. They play a key role in normal hemostasis. Normal platelet levels in adult patients are 150-400 x 109/L. Physiology Platelets are tiny (2-4 μm) cells that lack nuclei 1-3. They are mass prod...
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Thrombocytosis

Thrombocytosis (plural: thrombocytoses) is a general term and is defined as a rise in platelet count to over two standard deviations above the normal range. Its exact quantitative definition is variable, but generally equates to a platelet count greater than 400-450x109 cells/L.  Although there...
Article

Circumferential resection margin

Circumferential resection margin (CRM) is a term used to denote the standard plane of excision of total mesorectal excision, used for resection of rectal cancers. The anatomic correlate is the mesorectal fascia. The distance between tumor tissue or satellite tumor deposits and the mesorectal fas...
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Gene and protein notation

Correct usage of gene and protein notation has been laid down by the HUGO Gene Nomenclature Committee (HGNC) and on Radiopaedia we have decided to reflect this official guidance. In concordance with this standard scientific practice, gene symbols are italicized on Radiopaedia, but when the full...

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