Pheochromocytoma Review Article Text1 department of endocrinology, state university of new york, downstate medical center, brooklyn, ny 11203, united states. 2 department of endocrinology, state university of new york, downstate medical center, brooklyn, ny 11203, united states. Pheochromocytomas are catecholamine producing neuroendocrine tumors that can be adrenal or extra adrenal in origin. The classic symptoms of pheochromocytoma are headache, palpitation, anxiety and diaphoresis and the tumor can occur at any age with equal gender distribution. College Essay Introduction HelpIn patients with an established mutation or hereditary syndrome the condition may manifest at a younger age than in those with sporadic disease. Pheochromocytoma can be associated with certain genetic syndromes such as multiple endocrine neoplasia type 2 men 2 , neurofibromatosis nf and von hippel lindau vhl syndrome. Pheochromocytoma is diagnosed with biochemical confirmation of hormonal excess followed by anatomical localization ct or mri. In this review, we discuss in detail about the symptomatology, diagnosis, genetic aspects and management of pheochromocytoma. A pheochromocytoma see the image below is a rare, catecholamine secreting tumor that may precipitate life threatening hypertension. The tumor is malignant in 10% of cases but may be cured completely by surgical removal. Although pheochromocytoma has classically been associated with 3 syndromes von hippel lindau vhl syndrome, multiple endocrine neoplasia type 2 men 2 , and neurofibromatosis type 1 nf1 there are now 10 genes that have been identified as sites of mutations leading to pheochromocytoma. 24 hour urinary collection for catecholamines and metanephrines: 87.5% sensitivity, 99.7% specificity 2 test selection criteria include the following: consultation with an ophthalmologist to rule out retinal angiomas vhl disease see workup for more detail. A pheochromocytoma is a rare, catecholamine secreting tumor derived from chromaffin cells. The term pheochromocytoma in greek, phios means dusky, chroma means color, and cytoma means tumor refers to the color the tumor cells acquire when stained with chromium salts. These different genes produce tumors with different ages of onset, secretory profiles, locations, and potential for malignancy. 5 because of excessive catecholamine secretion, pheochromocytomas may precipitate life threatening hypertension or cardiac arrhythmias. Professional Resume Writing Services 7Th Arrondissement6 if the diagnosis of a pheochromocytoma is overlooked, the consequences can be disastrous, even fatal however, if a pheochromocytoma is found, it is potentially curable. 1 about 85% of pheochromocytomas are located within the adrenal glands, and 98% are within the abdomen. When such tumors arise outside of the adrenal gland, they are termed extra adrenal pheochromocytomas, or paragangliomas. Extra adrenal pheochromocytomas develop in the paraganglion chromaffin tissue of the nervous system. Common locations for extra adrenal pheochromocytomas include the organ of zuckerkandl close to the origin of the inferior mesenteric artery , bladder wall, heart, mediastinum, and carotid and glomus jugulare bodies. Approximately 10% of pheochromocytomas and 35% of extra adrenal pheochromocytomas are malignant. However, specific histologic features help to differentiate adrenal pheochromocytomas with a potential for biologically aggressive behavior from those that behave in a benign fashion. Among the features that suggest a malignant course are large tumor size and an abnormal dna ploidy pattern aneuploidy, tetraploidy. Pheochromocytoma is diagnosed by measuring elevated levels of metanephrines catecholamine metabolites in blood or urine. Ct scanning or mri is the preferred technique for localizing pheochromocytomas see the image below. Surgical resection of the tumor is the treatment of choice and usually cures the hypertension see workup and treatment. For discussion of pheochromocytoma in children, see the medscape reference article pediatric pheochromocytoma. In the absence of these 3 symptoms and hypertension, the diagnosis may be excluded. The spells may vary in occurrence from monthly to several times per day, and the duration may vary from seconds to hours. Typically, they worsen with time, occurring more frequently and becoming more severe as the tumor grows. These include multiple endocrine neoplasia men types 2a and 2b, neurofibromatosis von recklinghausen disease , and von hippel lindau vhl disease, as well as others see etiology. In general, these hereditary cancer syndromes are inherited in an autosomal dominant manner. Medical students often learn axioms in order to remember the key features of a disorder. The rule of 10 used to describe pheochromocytomas is a good example: 10 percent are extraadrenal, and of those, 10 percent are extraabdominal 10 percent are malignant 10 percent are found in patients who do not have hypertension and finally, 10 percent are hereditary. Phd Thesis Game Theory
© Copyright 2013 - 2016 - www.writehomestudio.com.
All rights reserved. |