Eugen Melcescu
University of Mississippi Medical Center
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Hormones (Greece) | 2012
Jana Phillips; Honey E. East; Sarah E. French; Eugen Melcescu; Robert D. Hamilton; William C. Nicholas; Jonathan F. Fratkin; Andrew D. Parent; Gustavo Luzardo; Christian A. Koch
INTRODUCTIONMalignant prolactinoma is an exceedingly rare endocrine tumor and cannot be diagnosed on histological grounds alone. Similarly to other neuroendocrine tumors such as pheochromocytoma, the mitoses index, Ki-67, p53, and others are utilized in helping understand whether a tumor is benign or malignant or to better predict tumor behavior. We here present the unusual case of an unfortunate young man with an aggressive prolactinoma, the complications of which led to his premature death.CASE REPORTA 25-year-old white man developed severe headaches, low energy, and decreased libido. A brain magnetic resonance imaging (MRI) showed a 4 × 3 × 2 cm pituitary tumor invading the left cavernous sinus. Laboratory findings revealed elevated prolactin (470 ng/mL) and adrenocorticotropic hormone (ACTH, 82 pg/ml) and decreased total testosterone (176 ng/dl). Visual fields showed superior quadrantanopia in the left eye. Transsphenoidal pituitary resection was undertaken. Pathology revealed a prolactinoma with atypical cells, diffuse p53 nuclear labeling, and a Ki-67 index of 23% (high). Postoperatively, prolactin remained elevated (725–891 ng/ml) and cabergoline was increased to 1 mg three times weekly, with serum prolactin further increasing to 3507 ng/ml five months postoperatively. Repeat MRI revealed extension of the tumor with optic chiasm compression and left orbit invasion. Because of acute left vision loss with ophthalmoplegia, an urgent left frontotemporal craniotomy and tumor resection were conducted. The Ki-67 index of the tumor was 24.8%, the mitotic figure immunostain phosphohistone-H3 positive. Sixty percent (60%) of tumor cells were positive for p53. Cabergoline was increased to 1 mg daily but prolactin remained elevated (770 ng/ml). The patient then underwent proton beam radiation to the area of concern involving the sella. Prolactin thereafter improved to 44 ng/ml. He then developed acute vision loss of the right eye with an MRI showing tumor in the right cavernous sinus. A 15 mm dural-based right temporal mass believed to be a metastasis was also noted. Following this scan, he was considered too high risk for debulking surgery and instead underwent gamma knife irradiation to the sella area. This shrank the right cavernous sinus tumor mass, while the right temporal mass increased in size. The patient developed blindness and left-sided weakness and required enteral feeding and tracheostomy after prolonged intubation. A trial of chemotherapy with temozolomide (350 mg daily for 5 days) near the end of his life was unsuccessful. He died on home hospice 31 months after his first surgery.CONCLUSIONHeadaches, vision changes, and symptoms of androgen deficiency syndrome can be manifestations of an aggressive prolactinoma that might require surgery and additional medical therapy including cabergoline and temozolomide with an unpredictable time of survival.
Hormone and Metabolic Research | 2012
Eugen Melcescu; Phillips J; Moll G; Jose S. Subauste; Christian A. Koch
Hypertension represents a major public and global health problem, most of which likely can be improved by lifestyle changes including changing dietary habits with less consumption of processed and preserved foods, which generally contain higher amounts of salt than freshly prepared food items. Among causes for endocrine hypertension are syndromes of mineralocorticoid excess. This group of mostly monogenic and acquired disorders typically causes hypertension through activation of the mineralocorticoid receptor either directly or indirectly via hormonal mediators and from overactive amiloride-sensitive epithelial sodium channels located in the distal tubule and collecting ducts of the kidneys. Apart from primary aldosteronism, mineralocorticoid excess can be caused by congenital adrenal hyperplasia (CAH) due to mutations of the 11beta-hydroxylase and 17alpha-hydroxylase genes, by inactivating mutations of the glucocorticoid receptor gene (Chrousos syndrome), endogenous hypercortisolism (Cushings syndrome), by mutations of the 11beta-hydroxysteroid dehydrogenase type 2 gene (apparent mineralocorticoid excess/AME) or licorice/carbenoxolone intake, mutations of the epithelial sodium channel genes (Liddle syndrome), mutations of the mineralocorticoid receptor gene (Geller syndrome), and by mutations in the WNK1, WNK4, KLHL3, CUL3 genes (pseudohypoaldosteronism type 2 or Gordon syndrome). Most of these conditions are treated by restricting dietary salt intake. However, some require special therapies including dexamethasone/hydrocortisone (CAH), spironolactone/eplerenone (AME), epithelial sodium channel inhibitors amiloride/triamterene (Liddle and Gordon syndrome), while in others spironolactone and MR antagonists may be contraindicated due to an abnormally structured MR (Geller syndrome). We here review the pathophysiology, diagnosis, and therapy of these rare conditions including the presentation of a patient with 11beta-hydroxylase deficiency.
Experimental and Molecular Pathology | 2012
Eugen Melcescu; Reed B. Hogan; Keith Brown; Stewart A. Boyd; Thomas L. Abell; Christian A. Koch
Serum gastrin levels exceeding 1000pg/ml (normal, <100) usually raise the suspicion for a neuroendocrine tumor (NET) that secretes gastrin. Rarely, such elevated gastrin levels are seen in patients with pernicious anemia which most commonly is associated with autoimmune gastritis (AG). AG can occur concomitantly with other autoimmune disorders including lymphocytic colitis (LC). Gastrin stimulates enterochromaffin-like cells which increase histamine secretion. Histamine excess can cause diarrhea as can bacterial overgrowth or LC. We present a 57-year-old woman with diarrhea, sporadic epigastric pain, and bloating. She also had a history of interstitial cystitis and took pentosan polysulfate and cetirizine. She had no history of ulcers, renal impairment or carcinoid syndrome. Fasting serum gastrin was 1846pg/ml. Esophagoduodenal gastroscopy and biopsies revealed chronic gastritis and a pH of 7 with low stomach acid. Serum gastrin and plasma chromogranin A were suggestive of a gastrinoma or NET. Pernicious anemia was unlikely. Imaging studies did not reveal any tumor. Random colonic biopsy was compatible with LC, possibly explaining her diarrhea, although we also considered excessive histamine from elevated gastrin, bacterial overgrowth, and pentosan polysulfate which can cause diarrhea and be misleading in this setting, pointing to the diagnosis of gastrinoma. At 4year follow-up in 2012, fasting serum gastrin was 1097pg/ml and the patient asymptomatic taking only cetirizine for nasal allergies. This case illustrates that diarrhea may be associated with very high serum gastrin levels in the setting of chronic gastritis, LC, and interstitial cystitis (pentosan use), without clear evidence for a gastrinoma or NET. If no history of ulcers or liver metastases is present in such cases, watchful observation rather than an extensive/invasive and costly search for a NET may be justified. Considering the various forms of polyglandular syndrome, this may represent a variant and we here provide an algorithm for working up such patients, while also reviewing literature on the intertwined relationship between the immune and endocrine systems.
Archive | 2013
Eugen Melcescu; Christian A. Koch
In addition to obesity, diabetes type 2, and the metabolic syndrome, hypertension represents a major public and global health problem, most of which can be improved by lifestyle changes, including changing dietary habits with less consumption of processed and preserved foods, which generally contain higher amounts of salt than freshly prepared food items. Amongst causes for endocrine hypertension are syndromes of mineralocorticoid excess typically resulting from overactive amiloride-sensitive sodium channels located in the distal convoluted tubules and collecting ducts of the kidney, as well as other tissues, including vascular smooth muscle. The net effect of such an overactivation, which occurs mostly in primary aldosteronism is sodium and water retention with volume expansion and hypertension that is exacerbated by a diet high in salt. Biochemically, plasma renin activity is suppressed and hypokalemia may be present. Aldosterone mediates its action through the mineralocortoid receptor (MR), which regulates salt homeostasis in the kidneys and plays a range of other roles in the vasculature, heart, brain, and adipose tissue.
Hormones (Greece) | 2013
Eugen Melcescu; William B. Horton; Karen T. Pitman; Vani Vijayakumar; Christian A. Koch
Euthyroid Graves’ orbitopathy (GO) combined with incidental papillary thyroid microcarcinoma has rarely been reported. CASE REPORT: A 61-year-old caucasian woman initially presented with progressive fatigue, exophthalmos, and thyroid function tests within normal limits. She underwent thyroidectomy, was found to have two incidental papillary thyroid microcarcinomas, and received radioactive iodine ablation to eliminate thyroid antigen. In addition to following her eye disease, TSH-receptor antibodies, thyroid stimulating immunoglobulins, and serum thyroglobulin measurements were recorded, demonstrating no evidence of thyroid cancer at four-year follow-up. At first, she had mild GO, developing into moderate-to-severe GO, and at 4 years she had Hertel measurements of 20 mm in both eyes. CONCLUSION: This report underscores the difficulty of managing GO even when thyroid function is normal(ized) and thyroid antigen exposure has been minimized. In addition, it illustrates why antithyroidal antibodies should be considered in cases of concomitant papillary thyroid cancer, as thyroid cells can be stimulated not only by TSH but also by TSH-receptor stimulating antibodies.
Neurosurgery | 2013
Eugen Melcescu; Anthony W. Gannon; Andrew D. Parent; Jonathan F. Fratkin; William C. Nicholas; Christian A. Koch; Ayman Galhom
Archive | 2012
Christian A. Koch; Eugen Melcescu
Archive | 2010
Eugen Melcescu; Elizabeth H Kemp; Vikas Majithia; Vani Vijayakumar; Gabriel I. Uwaifo; Christian A. Koch
Archive | 2015
Eugen Melcescu; Christian A. Koch
Archive | 2015
Eugen Melcescu; Christian A. Koch