Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/01/09 04:37:26」(JST)

wiki en

Somatostatinoma is a malignant tumor of the delta cells of the endocrine pancreas that produces somatostatin. Increased levels of somatostatin inhibit pancreatic hormones and gastrointestinal hormones. Thus somatostatinomas are associated with mild diabetes mellitus (due to inhibition of insulin release), steatorrhoea and gallstones (due to inhibition of cholecystokinin release), and achlorhydria (due to inhibition of gastrin release). Somatostatinomas are commonly found in head of pancreas.

Pathophysiology

In a normal subject actions of somatostatin include:

In the anterior pituitary gland, the effects of somatostatin are:

Inhibit the release of growth hormone thus opposing the effects of growth hormone-releasing hormone (GHRH)
Inhibit the release of thyroid-stimulating hormone (TSH)

Somatostatin suppresses the release of gastrointestinal hormones

Gastrin
Cholecystokinin (CCK)
Secretin
Motilin
Vasoactive intestinal peptide (VIP)
Gastric inhibitory polypeptide (GIP)
Enteroglucagon

Lowers the rate of gastric emptying, and reduces smooth muscle contractions and blood flow within the intestine
Suppresses the release of pancreatic hormones

Inhibits the release of insulin
Inhibits the release of glucagon

Suppresses the exocrine secretory action of pancreas.

This explains how abnormally elevated somatostatin can cause diabetes mellitus, by inhibiting insulin secretion, steatorrhoea by inhibiting cholecystokinin and secretin, gall stones by inhibiting cholecystokinin which normally induce gallbladder myocytes to contract, and hypochlorhydria caused by inhibiting gastrin, which normally stimulate acid secretion.

Somatostatinomas are associated with calcium deposits called psammoma bodies.

Treatment

Treatment is by chemotherapy with streptozocin, dacarbazine, doxorubicin or by 'watchful waiting' and surgical debulking via Whipple procedure and other resections of the gastrointestinal organs affected.^[1]

References

^ Ellison TA, Edil BH (2012). "The current management of pancreatic neuroendocrine tumors.". Adv Surg (46): 283–296. PMID 22873046.

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. ソマトスタチン産生腫瘍：臨床的特徴、診断、およびマネージメント somatostatinoma clinical manifestations diagnosis and management
2. 膵神経内分泌腫瘍（膵島細胞腫瘍）の分類、疫学、臨床症状、局在、および病期分類 classification epidemiology clinical presentation localization and staging of pancreatic neuroendocrine tumors islet cell tumors
3. 散発性膵神経内分泌腫瘍の外科的切除 surgical resection of sporadic pancreatic neuroendocrine tumors
4. Metastatic well-differentiated pancreatic neuroendocrine tumors: Systemic therapy options to control tumor growth and symptoms of hormone hypersecretion
5. ソマトスタチンの生理学とその類縁体 physiology of somatostatin and its analogues

English Journal

Gastrointestinal: Neurofibromatosis type 1, duodenal somatostatinoma and gastrointestinal stromal tumors; a triad worth remembering.

Njei B1, Sanchez H.
Journal of gastroenterology and hepatology.J Gastroenterol Hepatol.2014 Apr;29(4):663. doi: 10.1111/jgh.12531.
PMID 24646427

Cotargeting the PI3K and RAS Pathways for the Treatment of Neuroendocrine Tumors.

Valentino JD1, Li J, Zaytseva YY, Mustain WC, Elliott VA, Kim JT, Harris JW, Campbell K, Weiss H, Wang C, Song J, Anthony L, Townsend CM Jr, Evers BM.Author information 1Authors' Affiliations: Departments of Surgery, Internal Medicine, and Biostatistics; Markey Cancer Center, University of Kentucky, Lexington, Kentucky; and Department of Surgery, University of Texas Medical Branch, Galveston, Texas.AbstractBackground: The precise involvement of the PI3K/mTOR and RAS/MEK pathways in carcinoid tumors is not well defined. Therefore, the purpose of our study was to evaluate the role these pathways play in carcinoid cell proliferation, apoptosis, and secretion and to determine the effects of combined treatment on carcinoid tumor inhibition. Methods: The human neuroendocrine cell lines BON (pancreatic carcinoid), NCI-H727 (lung carcinoid), and QGP-1 (somatostatinoma) were treated with either the pan-PI3K inhibitor, BKM120, or the dual PI3K-mTOR inhibitor, BEZ235, alone or in combination with the MEK inhibitor, PD0325901; proliferation, apoptosis, and protein expression were assessed. Peptide secretion was evaluated in BON and QGP-1 cells. The antiproliferative effect of BEZ235, alone or combined with PD0325901, was then tested in vivo.
Clinical cancer research : an official journal of the American Association for Cancer Research.Clin Cancer Res.2014 Mar 1;20(5):1212-22. doi: 10.1158/1078-0432.CCR-13-1897. Epub 2014 Jan 17.
Background: The precise involvement of the PI3K/mTOR and RAS/MEK pathways in carcinoid tumors is not well defined. Therefore, the purpose of our study was to evaluate the role these pathways play in carcinoid cell proliferation, apoptosis, and secretion and to determine the effects of combined treat
PMID 24443523

Mosaicism in HIF2A-Related Polycythemia-Paraganglioma Syndrome.

Buffet A1, Smati S, Mansuy L, Ménara M, Lebras M, Heymann MF, Simian C, Favier J, Murat A, Cariou B, Gimenez-Roqueplo AP.Author information 1Assistance Publique-Hôpitaux de Paris (A.B., C.S., A-P.G.-R.), Hôpital Européen Georges Pompidou (HEGP), Service de Génétique, 75908 Paris, France; Clinique d'Endocrinologie (S.S., M.L., A.M., B.C.), l'Institut du Thorax, Centre Hospitalier Universitaire (CHU) de Nantes, 44007 Nantes, France; Département d'Oncologie et d'Hématologie Pédiatriques et de Thérapie Cellulaire (L.M.), CHU de Nancy, Hôpital d'Enfants, 54500 Vandœuvre-lès-Nancy, France; Inserm (M.M., J.F., A.-P.G.-R.), Unité Mixte de Recherche 970, Centre de recherche cardiovasculaire de l'HEGP, 75015 Paris, France; Service d'Anatomopathologie (M.-F.H.), CHU de Nantes, 44007 Nantes, France; INSERM (M.-F.H.), UMR957, Faculté de Médecine, 44035 Nantes, France; and Université Paris Descartes (J.F., A.-P.G.-R.), Faculté de Médecine, 75006 Paris Cité Sorbonne, France.AbstractContext: HIF2A germline mutations were known to cause congenital polycythemia. Recently, HIF2A somatic mutations were found in several patients with polycythemia and paraganglioma, pheochromocytoma, or somatostatinoma, suggesting the occurrence of a de novo postzygotic HIF2A mutation that has not been demonstrated clearly. Patients: Patient 1 is a woman suffering from polycythemia diagnosed at the age of 16 years. She was operated on for a pheochromocytoma at 45 years and for two abdominal paragangliomas at 59 years. She was also diagnosed with somatostatinoma. Patient 2 is a young boy who suffered from polycythemia since infancy. He underwent surgery for a nonfunctional adrenal paraganglioma at the age of 9 years. Methods: We sequenced by Sanger and next-generation sequencing the HIF2A gene in DNA extracted from tumors, leukocytes, and buccal cells. Results: In patient 1, we identified a somatic HIF2A mutation (c.1586T>C; p.Leu529Pro) in DNA extracted from both paragangliomas. The mutation was detected as a somatic mosaic in DNA extracted from somatostatinoma and was absent from germline DNA. In patient 2, we found an HIF2A heterozygous mutation (c.1625T>C; p.Leu542Pro) in the paraganglioma, but the mutation was also present as a mosaic in leukocyte DNA and in DNA extracted from buccal cells (3.3 and 8.96% of sequencing reads, respectively). Both mutations disrupt the hydroxylation domain of the HIF2α protein. Conclusions: Our study shows that HIF2A-related tumors are caused by postzygotic mutations occurring in early developmental stages. Potential germline mosaicism should be considered during the familial genetic counseling when an individual has been diagnosed with HIF2A-related polycythemia-paraganglioma syndrome.
The Journal of clinical endocrinology and metabolism.J Clin Endocrinol Metab.2014 Feb;99(2):E369-73. doi: 10.1210/jc.2013-2600. Epub 2013 Nov 25.
Context: HIF2A germline mutations were known to cause congenital polycythemia. Recently, HIF2A somatic mutations were found in several patients with polycythemia and paraganglioma, pheochromocytoma, or somatostatinoma, suggesting the occurrence of a de novo postzygotic HIF2A mutation that has not be
PMID 24276449

Japanese Journal

von Recklinghausen 病に合併した Vater 乳頭部ソマトスタチノーマの1例

川口章吾,山形亮,高橋誠司,齋藤太郎,村田有志,八木橋操六,福田眞作
日本消化器内視鏡学会雑誌 = Gastroenterological endoscopy 53(5), 1435-1440, 2011-05-20
症例は36歳女性．タール便を排泄後に意識消失をきたし当院へ救急搬送された．全身の皮膚にCafé-au-lait斑を認めた．上部消化管内視鏡検査で十二指腸下行脚に腫瘍性病変を認め，中心の潰瘍からは出血を認めた．保存的治療後，幽門輪温存膵頭十二指腸切除術が施行されたが，腫瘍は膵頭部にまで浸潤しており，♯13aのリンパ節に転移を認めた．腫瘍は免疫組織学的検査の結果ソマトスタチノーマであると診断された．
NAID 10029092470

Asymptomatic Somatostatinoma of the Pancreatic Head : Report of a Case

ARIMA HIDEO,NATSUGOE SHOJI,MAEMURA KOUSEI,HATA YOUICHI,KUMANOHOSO TORU,IMAMURA HIROSHI,MATAKI YUKO,KURAHARA HIROSHI,SHINCHI HIROYUKI,TAKAO SONSHIN,AIKOU TAKASHI
Surgery today : the Japanese journal of surgery 40(6), 569-573, 2010-06-01
NAID 10027396184