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12 results found

CA 19-9 elevation

CA 19-9 (carbohydrate antigen 19-9 or cancer antigen) is a serum antigen (monosialoganglioside) that has increased diagnostic use in the management of several malignancies, mainly of hepatopancreaticobiliary origin. It is non-specific, however, and can rise in both malignant and non-malignant co...

Carcinoembryonic antigen

Serum carcinoembryonic antigen (CEA) is a cell-adhesive glycoprotein that was discovered in colorectal cancer in 1965, and is hence one of the oldest and most used tumour markers. Its name derives from its normal expression in fetoembryonic liver, gut and pancreas tissue. Normal range of CEA is...

Circumferential resection margin

The circumferential resection margin (CRM) is a term used in rectal carcinoma excision surgery (such as total mesorectal excision (TME)). Pathologic evaluation of the resection margin on the excised rectum has been considered important for determining the risk of local recurrence. A margin of ≤...

Faecal calprotectin

Faecal calprotectin (FCAL) is a protein which is a marker of inflammation of the gut used as a diagnostic tool and marker of disease activity for Crohn disease and ulcerative colitis. Biochemistry Calprotectin is a protein complex from the S-100 family, which is formed of three polypeptide cha...


Glucagon is a polypeptide hormone central to the regulation of glucose homeostasis, acting as an antagonist to insulin. In imaging it is used as an antiperistaltic agent in GI studies, although its clinical efficacy is controversial.  Structure Glucagon is a 29-amino acid polypeptide hormone t...

Haggitt level

The Haggitt level is a histopathological term used for describing the degree of infiltration from a malignant polypoidal lesion. Levels of invasion 0: carcinoma in situ or intramucosal carcinoma 1: invasion of the submucosa, but limited to the head of the polyp 2: invasion extending into the...

Kikuchi level

The Kikuchi level is a histopathological term used for describing the degree of infiltration of a sessile early invasive colorectal cancer1. Preoperative assessment of the level of invasion using this classification may decrease the incidence of unnecessary surgery for sessile polyps.  Levels o...


Lipase, more specifically pancreatic lipase, is an enzyme produced in the pancreas and is responsible for the digestion of fat molecules. It may be raised in numerous pancreatic, hepatobilary and other diseases but is most commonly associated with acute pancreatitis. Physiological basis Lipase...


Metaplasia is a general pathology term that refers to 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 oesophagus: normal squamous epithelium replac...

Normal postmortem changes in the gastrointestinal tract

Normal postmortem changes in the gastrointestinal tract​ refers to the normal changes that can be expected to be seen in the gastrointestinal tract on post-mortem imaging. Radiographic features CT The following changes may be present in the abdomen and gastrointestinal tract 1: intraluminal ...

Tissue tropism

Tissue tropism is a phenomenon by which certain host tissues preferentially support the growth and proliferation of pathogens. This concept is central to the radiological evaluation of infectious disease.  Pathology As infections that display tissue tropism will thrive in certain tissue locati...

Vitamin B3

Vitamin B3 (niacin or nicotinic acid) is a water-soluble vitamin that is an important part of the coenzyme nicotinamide adenine dinucleotide (NAD+) which is involved in many reactions of cellular metabolism. Related pathology Pathological manifestations occur in niacin deficiency, which is kno...

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