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| {{SI}}
| | #REDIRECT [[Glucagonoma]] |
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| == Overview ==
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| A '''glucagonoma''' is a rare [[tumor]] of the [[alpha cell]]s of the [[pancreas]] that results in up to a 1000-fold overproduction of the [[hormone]] [[glucagon]]. Alpha cell tumors are commonly associated with [[glucagonoma syndrome]], though similar symptoms are present in cases of [[pseudoglucagonoma syndrome]] in the absence of a glucagon-secreting tumor.
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| == History ==
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| Fewer than 250 cases of glucagonoma have been described in the literature since their first description by Becker in [[1942]]. Because of its rarity (fewer than one in 20 million worldwide), long-term survival rates are as yet unknown.
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| == Symptoms ==
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| The primary [[physiology|physiological]] effect of glucagonoma is an overproduction of the [[peptide]] hormone [[glucagon]], which enhances [[blood glucose]] levels through the activation of [[catabolism|catabolic]] processes including [[gluconeogenesis]] and [[lipolysis]]. Gluconeogenesis produces [[glucose]] from [[protein]] and [[amino acid]] materials; lipolysis is the breakdown of [[adipose tissue|fat]]. The net result is [[hyperglucagonemia]], decreased blood levels of [[amino acid]]s ([[hypoaminoacidemia]]), [[anemia]], [[diarrhea]], and weight loss of 5-15 [[kg]].
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| [[Necrolytic migratory erythema]] (NME) is a classical symptom observed in patients with glucagonoma and is present in 80% of cases. Associated NME is characterized by the spread of erythematous blisters and swelling across areas subject to greater friction and pressure, including the lower [[abdomen]], [[buttock]]s, [[perineum]], and [[groin]].
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| [[Diabetes mellitus]] also frequently results from the [[insulin]] and [[glucagon]] imbalance that occurs in glucagonoma.<ref>{{cite journal |author=Koike N, Hatori T, Imaizumi T, ''et al'' |title=Malignant glucagonoma of the pancreas diagnoses through anemia and diabetes mellitus |journal=Journal of hepato-biliary-pancreatic surgery |volume=10 |issue=1 |pages=101-5 |year=2003 |pmid=12918465 |doi=}}</ref> Diabetes mellitus is present in 80-90% of cases of glucagonoma, and is exacerbated by preexisting [[insulin resistance]].
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| == Diagnosis ==
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| A [[blood serum]] glucagon concentration of 1000 pg/[[milliliter|mL]] or greater is indicative of glucagonoma (the normal range is 50-200 pg/mL).
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| Blood tests may also reveal abnormally low concentrations of amino acids, [[zinc]], and [[essential fatty acid]]s, which are thought to play a role in the development of NME. Skin [[biopsy|biopsies]] may also be taken to confirm the presence of NME.
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| A [[complete blood count|CBC]] can uncover anemia, which is an abnormally low level of [[hemoglobin]].
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| The tumor itself may be localized by any number of radiographic modalities, including [[angiography]], [[computed tomography|CT]], [[magnetic resonance imaging|MRI]], [[positron emission tomography|PET]], and [[endoscopic ultrasound]]. [[Laparotomy]] is useful for obtaining [[histology|histologic]] samples for analysis and confirmation of the glucagonoma.
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| == Treatment ==
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| Heightened glucagon secretion can be treated with the administration of [[Somatostatin|octreotide, a somatostatin analog]], which inhibits the release of glucagon.<ref>{{cite journal |author=Moattari AR, Cho K, Vinik AI |title=Somatostatin analogue in treatment of coexisting glucagonoma and pancreatic pseudocyst: dissociation of responses |journal=Surgery |volume=108 |issue=3 |pages=581-7 |year=1990 |pmid=2168587 |doi=}}</ref> [[Doxorubicin]] and [[streptozotocin]] have also been used successfully to selectively damage alpha cells of the pancreatic islets. These do not destroy the tumor, but help to minimize progression of symptoms.
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| The only curative therapy for glucagonoma is [[surgery|surgical]] resection, where the tumor is removed. Resection has been known to reverse symptoms in some patients.
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| == References ==
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| <references/>
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| {{SIB}}
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| [[de:Glucagonom]]
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| {{WH}}
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| {{WikiDoc Sources}}
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| [[Category:Types of cancer]]
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| [[Category:Disease]]
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| [[Category:Endocrinology]]
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| [[Category:Oncology]]
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