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{{WBRQuestion
{{WBRQuestion
|QuestionAuthor={{SSK}} (Reviewed by Will Gibson) {{Alison}} (Reviewed by Serge Korjian)
|QuestionAuthor={{YD}} (Reviewed by Will Gibson) {{Alison}} (Reviewed by Serge Korjian)
|ExamType=USMLE Step 1
|ExamType=USMLE Step 1
|MainCategory=Pathology
|MainCategory=Pathology
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|SubCategory=Endocrine
|SubCategory=Endocrine
|Prompt=A 45-year-old woman presents to the physician’s office with complaints of severe diarrhea of several days duration.  The patient’s medical history is significant for recurrent kidney stones and a parathyroidectomy 8 years ago.  Her fasting gastrin level is elevated and endoscopy reveals multiple ulcers in the stomach, duodenum, and jejunum.  Which of the following findings is most frequently associated with this patient's condition?
|Prompt=A 45-year-old woman presents to the physician’s office with complaints of severe diarrhea of several days duration.  The patient’s medical history is significant for recurrent kidney stones and a parathyroidectomy 8 years ago.  Her fasting gastrin level is elevated and endoscopy reveals multiple ulcers in the stomach, duodenum, and jejunum.  Which of the following findings is most frequently associated with this patient's condition?
|Explanation=The patient in this vignette most likely has ''multiple endocrine neoplasia type I'' (MEN 1). We know from the patient's past medical history that she likely had a parathyroid adenoma. Parathyroid adenomas can secrete PTH and thereby increase serum calcium and decrease serum potassium. Increased serum calcium can be lead to elevated calcium passing into the urine, thereby increasing the risk of calcium oxalate kidney stones. The definitive treatment of these tumors is surgical removal (parathyroidectomy) as in this patient.<br>
|Explanation=The patient in this vignette most likely has ''multiple endocrine neoplasia type I'' (MEN 1). From the patient's past history of parathyroidectomy, it is highly likely that she had a parathyroid adenoma. Parathyroid adenomas classically secrete excessive PTH leading to elevated serum calcium and decreased serum phosphate levels. The increased serum calcium also leads to excess urinary excretion, increasing the risk of calcium oxalate kidney stones.<br>
The patient now presents with symptoms highly consistent with a gastrinoma. These are gastrin-secreting tumors that form in either the pancreas or the duodenum. Recall that gastrin is a peptide hormone that stimulated parietal cells to increase secretion of gastric acid. Patients with gastrinomas therefore frequently develop multiple ulcers due to excessive gastric acid production in the stomach. Nearly 25% of gastrinoma patients have MEN 1. A patient with who has developed both parathyroid adenoma and gastrinoma is certainly affected by MEN 1.
The current presentation is highly consistent with a gastrinoma, a gastrin-secreting tumor that arises from tissues of either the pancreas or the duodenal wall. Gastrin is a peptide hormone that stimulates parietal cells to increase gastric acid secretion. Patients with gastrinomas therefore frequently develop multiple ulcers due to excessive gastric acid production in the stomach. Nearly 25% of gastrinoma patients have MEN 1. A patient who has developed both parathyroid adenoma and gastrinoma is highly likely to be affected by MEN 1. [[MEN I syndrome]] is characterized by parathyroid tumors, pituitary tumors, and pancreatic endocrine tumors. Several subtypes of pancreatic endocrine tumors are associated with MEN 1, including gastrinoma, insulinoma, VIPoma, or glucagonoma. All of the MEN syndromes are dominantly inherited genetic disorders. MEN1 syndrome is caused by mutations in the MEN1 gene that ecodes the tumor suppressor menin.
 
[[MEN I syndrome]] is characterized by [[parathyroid]] tumors, [[pituitary]] tumors, and pancreatic endocrine tumors. Remember the three P's of MEN 1! Several subtypes of pancreatic endocrine tumors are associated with MEN1, including [[gastrinoma]], [[insulinoma]], [[VIPoma]], or [[glucagonoma]].
 
All of the MEN syndromes are dominantly inherited genetic disorders. MEN1 syndrome is caused by mutations in the MEN1 gene that ecodes the tumor suppressor menin.


A good way to remember which organ systems are affected by the different MEN syndromes is:
A good way to remember which organ systems are affected by the different MEN syndromes is:
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|AnswerCExp=Medullary thyroid cancer frequently occurs in MEN 2A and MEN 2B syndromes.
|AnswerCExp=Medullary thyroid cancer frequently occurs in MEN 2A and MEN 2B syndromes.
|AnswerD=Prolactinoma
|AnswerD=Prolactinoma
|AnswerDExp=Prolactinoma, a pituitary tumor, frequently occurs in MEN I syndrome. Prolactin causes an increase in dopamine release from the arcuate nucleus of the hypothalamus and thereby inhibits pituitary release of GnRH. A decrease in GnRH causes a decrease in LH and FSH, and consequently decreases sex hormone concentrations in the blood. Because of this cascade, decreased libido is one of the most prominent symptoms of a prolactinoma.
|AnswerDExp=Prolactinoma, a pituitary tumor, frequently occurs in MEN I syndrome.
|AnswerE=Carcinoid tumor
|AnswerE=Carcinoid tumor
|AnswerEExp=Carcinoid tumor is an endocrine tumor, but is not frequently associated with MEN syndrome.
|AnswerEExp=Carcinoid tumor is an endocrine tumor, but is not frequently associated with MEN syndrome.

Revision as of 15:57, 20 February 2015

 
Author [[PageAuthor::Yazan Daaboul, M.D. (Reviewed by Will Gibson) (Reviewed by Alison Leibowitz) (Reviewed by Serge Korjian)]]
Exam Type ExamType::USMLE Step 1
Main Category MainCategory::Pathology
Sub Category SubCategory::Endocrine
Prompt [[Prompt::A 45-year-old woman presents to the physician’s office with complaints of severe diarrhea of several days duration. The patient’s medical history is significant for recurrent kidney stones and a parathyroidectomy 8 years ago. Her fasting gastrin level is elevated and endoscopy reveals multiple ulcers in the stomach, duodenum, and jejunum. Which of the following findings is most frequently associated with this patient's condition?]]
Answer A AnswerA::Oral ganglioneuroma
Answer A Explanation AnswerAExp::Oral ganglioneuromatosis frequently occurs in patients with MEN2B syndrome.
Answer B AnswerB::Pheochromocytoma
Answer B Explanation AnswerBExp::Pheochromocytoma frequently occurs in MEN 2A and MEN 2B syndromes.
Answer C AnswerC::Medullary thyroid cancer
Answer C Explanation AnswerCExp::Medullary thyroid cancer frequently occurs in MEN 2A and MEN 2B syndromes.
Answer D AnswerD::Prolactinoma
Answer D Explanation AnswerDExp::Prolactinoma, a pituitary tumor, frequently occurs in MEN I syndrome.
Answer E AnswerE::Carcinoid tumor
Answer E Explanation AnswerEExp::Carcinoid tumor is an endocrine tumor, but is not frequently associated with MEN syndrome.
Right Answer RightAnswer::D
Explanation [[Explanation::The patient in this vignette most likely has multiple endocrine neoplasia type I (MEN 1). From the patient's past history of parathyroidectomy, it is highly likely that she had a parathyroid adenoma. Parathyroid adenomas classically secrete excessive PTH leading to elevated serum calcium and decreased serum phosphate levels. The increased serum calcium also leads to excess urinary excretion, increasing the risk of calcium oxalate kidney stones.

The current presentation is highly consistent with a gastrinoma, a gastrin-secreting tumor that arises from tissues of either the pancreas or the duodenal wall. Gastrin is a peptide hormone that stimulates parietal cells to increase gastric acid secretion. Patients with gastrinomas therefore frequently develop multiple ulcers due to excessive gastric acid production in the stomach. Nearly 25% of gastrinoma patients have MEN 1. A patient who has developed both parathyroid adenoma and gastrinoma is highly likely to be affected by MEN 1. MEN I syndrome is characterized by parathyroid tumors, pituitary tumors, and pancreatic endocrine tumors. Several subtypes of pancreatic endocrine tumors are associated with MEN 1, including gastrinoma, insulinoma, VIPoma, or glucagonoma. All of the MEN syndromes are dominantly inherited genetic disorders. MEN1 syndrome is caused by mutations in the MEN1 gene that ecodes the tumor suppressor menin.

A good way to remember which organ systems are affected by the different MEN syndromes is: MEN I (3 Ps) - Pituitary, Parathyroid, Pancreatic MEN IIa (1M,2Ps) - Medullary Thyroid Ca, Pheochromocytoma, Parathyroid MEN IIb (2Ms,1P) - Medullary Thyroid Ca, Marfanoid habitus/mucosal neuroma, Pheochromocytoma
Educational Objective: MEN I syndrome often manifests with pituitary tumors, parathyroid tumors, or pancreatic endocrine tumors.
References: Thakker, R. V., Newey, P. J., Walls, G. V., Bilezikian, J., Dralle, H., Ebeling, P. R., ... & Brandi, M. L. (2012). Clinical practice guidelines for multiple endocrine neoplasia type 1 (MEN1). The Journal of Clinical Endocrinology & Metabolism, 97(9), 2990-3011.
Basuroy R, Srirajaskanthan R, Prachalias A, Quaglia A, Ramage JK. Review article: the investigation and management of gastric neuroendocrine tumours. Aliment Pharmacol Ther. May 2014;39(10):1071-84.
First Aid 2014 page 329
First Aid 2015 page 337]]

Approved Approved::Yes
Keyword WBRKeyword::Prolactinoma, WBRKeyword::Pheochromocytoma, WBRKeyword::Gastrinoma, WBRKeyword::Neoplasia, WBRKeyword::MEN I, WBRKeyword::Cancer, WBRKeyword::Wermer syndrome, WBRKeyword::Diarrhea, WBRKeyword::Ulcers, WBRKeyword::Gastrinoma, WBRKeyword::Tumor, WBRKeyword::Pancreatic cancer, WBRKeyword::Multiple endocrine neoplasia
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