1/12. Middle ear adenomatous tumor with a predominant neuroendocrine component.A primary adenomatous tumor of the middle ear was examined by light microscopy, ultrastructural and immunohistochemical techniques. In support of its extensive neuroendocrine differentiation, was the diffuse detection of neuron-specific enolase (NSE) and positive immunoreaction with antibodies to chromogranin and synaptophysin. The great majority of tumor cells contained neurosecretory granules and intraluminal mucin production could be focally detected. These characteristics confirm the diagnosis of a middle ear adenomatous tumor (meat) of a biphasic nature and with a prominent neuroendocrine component.- - - - - - - - - - ranking = 1keywords = adenoma (Clic here for more details about this article) |
2/12. Middle ear adenoma with neuroendocrine differentiation.The lining of the middle ear cleft is normally a thin modified respiratory type mucosa. Normal mucosa of the middle ear is devoid of salivary type seromucous glands. Middle ear adenoma is a rare tumor that seems to be derived from the middle ear mucosa. This tumor has been previously described under a variety of names because of its different nature and biological behavior. We herein report a case of middle ear tumor that shows adenomatous and neuroendocrine features. A 64-year-old woman presented with a history of hearing loss, tinnitus and stuffy feeling of the right ear. The patient was treated two times for ear polyp. She finally underwent a tympanomastoidectomy and there was no evidence of recurrence 18 months after the procedure. Histopathological examination displayed cuboidal and columnar cells, arranged as glands, trabeculae and solid sheets. Neuroendocrine differentiation was revealed by immunohistochemical staining with polyclonal antibodies against neuron specific enolase and chromogranin antigens.- - - - - - - - - - ranking = 1keywords = adenoma (Clic here for more details about this article) |
3/12. Carcinoid syndrome, acromegaly, and hypoglycemia due to an insulin-secreting neuroendocrine tumor of the liver.We report a patient with a hepatic neuroendocrine tumor showing an extraordinary change of the tumor's humoral manifestations from a clinically documented extrapituitary acromegaly and a typical carcinoid syndrome toward a hyperinsulinemic hypoglycemia syndrome. At the primary manifestation of the tumor, an increased serum level of insulin-like growth factor i due to overproduction of GHRH and an increased urinary excretion of 5-hydroxyindoleacetic acid were found. The clinical manifestation of the GHRH excess was an arthralgia, which resolved completely after operative tumor debulking and normalization of insulin-like growth factor i and GHRH serum levels. The secretion of serotonin from the tumor resulted in a typical carcinoid syndrome including right-sided valvular heart disease. On the later course of the disease, the humoral manifestations of the tumor were supplemented by the secretion of insulin, leading to recurrent severe hyperinsulinemic hypoglycemia. The hepatic origin of hyperinsulinism was demonstrated by selective arterial calcium stimulation. Moreover, tumor cells revealed insulin and c-peptide immunoreactivity in the immunohistochemical analysis. The patient died 8 yr after the initial diagnosis of the tumor, and a carefully performed autopsy procedure confirmed the absence of any extrahepatic tumor manifestation.- - - - - - - - - - ranking = 0.27545701999217keywords = pituitary (Clic here for more details about this article) |
4/12. The pigmented "black" neuroendocrine tumor of the pancreas: a question of origin.BACKGROUND: Pigmented neoplasms are extremely rare in the pancreas, and, when black pigment is identified, it often suggests the diagnosis of metastatic melanoma. The authors describe two patients with pigmented "black" neuroendocrine tumors of the pancreas. One patient had an incidental (0.5 cm) finding, and the second patient had a well-demarcated, 4.5-cm mass identified by computerized tomography that was consistent with an islet cell tumor. methods: The two neoplasms were resected surgically and studied by light microscopy using hematoxylin and eosin (H&E), Fontana-Masson, and iron stains. The neoplasms were examined immunohistochemically, and ultrastructural analysis was performed. RESULTS: H&E stains revealed nests of well-differentiated cells with small, round, centrally placed nuclei. The cytoplasm of the neoplastic cells was pink and granular and contained abundant brown-black pigment. Angiolymphatic and perineural invasion were identified in the larger neoplasm. Both neoplasms demonstrated a positive reaction with a Fontana-Masson stain, which was susceptible to bleaching, and a negative reaction to an iron stain. Immunohistochemical stains showed that neoplastic cells expressed chromogranin and synaptophysin but did not express HMB-45, S-100 protein, glucagon, or insulin. Ultrastructural examination revealed regular neurosecretory granules (100-150 nm) and large, irregularly shaped, electron-dense granules with small lipid inclusions consistent with lipofuscin. CONCLUSIONS: These pigmented pancreatic neoplasms are similar histologically and radiographically to the "black adenoma" of the adrenal gland. It is important to recognize these tumors, because they may mimic metastatic melanoma.- - - - - - - - - - ranking = 0.16666666666667keywords = adenoma (Clic here for more details about this article) |
5/12. Cystic pancreatic neuroendocrine tumors: is preoperative diagnosis possible?Pancreatic neuroendocrine tumors rarely undergo cystic degeneration leading to a radiologic appearance, which is often interpreted as a pancreatic mucinous cystadenoma or pseudocyst. We reviewed our experience with 38 neuroendocrine tumors, four of which were cystic, and 24 other cystic pancreatic tumors (mucinous cystadenoma [n = 5], cystadenocarcinoma [n = 6], serous cystadenoma [n = 3], solid/cystic papillary neoplasm [n = 3], intraductal papillary mucinous tumor [n = 6], and mucinous adenocarcinoma [n = 1]) managed operatively between 1990 and 2000. This review was undertaken to identify clinical and pathologic features useful for preoperative diagnosis of cystic neuroendocrine tumors. Two of the four patients with cystic neuroendocrine tumors presented with abdominal pain, one patient was asymptomatic, and one patient had hypoglycemia. Three of the four cystic neuroendocrine tumors were identified by CT scan, and none were biopsied preoperatively. Preoperative diagnoses included mucinous cystadenoma in two patients (n = 2), pancreatic cystic neoplasm in one patient, (n = 1) and insulinoma in one patient (n = 1). All four cystic neuroendocrine tumors were benign and were completely resected (distal pancreatectomy [n = 2], enucleation [n = 2]). Cystic neuroendocrine tumors are difficult to diagnose preoperatively because the majority of these tumors are nonfunctional, and CT does not differentiate these tumors from other cystic neoplasms. Cystic neuroendocrine tumors represent a subgroup of pancreatic cystic and neuroendocrine tumors with malignant potential. Their high resectability rate further supports the role of surgical exploration and resection in the treatment of pancreatic cystic neoplasms.- - - - - - - - - - ranking = 0.66666666666667keywords = adenoma (Clic here for more details about this article) |
6/12. acromegaly secondary to growth hormone releasing hormone secretion.BACKGROUND: acromegaly secondary to growth hormone releasing hormone (GHRH) secretion is exceptionally rare. AIM: To report a case of acromegaly diagnosed in 1984 and assumed to be pituitary in origin. Sixteen years later, the cause was found to be a GHRH secreting neuroendocrine pancreatic tumour. METHOD: A case report. CONCLUSION: Although ectopic GHRH production is very rare, endocrinologists should be aware of this possibility in acromegaly patients if a pituitary tumour was not detected using pituitary imaging.- - - - - - - - - - ranking = 0.82637105997651keywords = pituitary (Clic here for more details about this article) |
7/12. Cutaneous neuroendocrine adenoma: an uncommon neoplasm.BACKGROUND: Cutaneous neuroendocrine neoplasms are typically malignant. Benign cutaneous neuroendocrine tumors are uncommon. methods: We report the case of a 32-year-old female who presented with a granular mass in the right external auditory canal. RESULTS: Microscopic examination of a shave biopsy revealed a poorly circumscribed neoplasm with glandular differentiation. While cytologic atypia and mitotic activity were not evident, pagetoid spread was observed. immunohistochemistry was indicative of neuroendocrine origin. CONCLUSIONS: This case report of neuroendocrine adenoma indicates that this entity should be entertained in the repertoire of conditions affecting the external ear.- - - - - - - - - - ranking = 0.83333333333333keywords = adenoma (Clic here for more details about this article) |
8/12. Median pancreatectomy: a report of three cases.Conventional pancreatic resections may be unnecessary for tumors of the pancreas that are benign or of low malignant potential and can place the patient at increased risk of developing postoperative exocrine and endocrine complications. Median pancreatectomy is an option that has been investigated in the management of such tumors located in the body of the pancreas. We present our experience with three women who underwent this procedure successfully for neuroendocrine tumors (2) and cystadenoma (1).- - - - - - - - - - ranking = 0.16666666666667keywords = adenoma (Clic here for more details about this article) |
9/12. Variable regions of chromosome 11 loss in different pathological tissues of a patient with the multiple endocrine neoplasia type I syndrome.multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited disorder characterized by nodular proliferation of the parathyroid glands and tumors of the anterior pituitary gland, the endocrine pancreas, and the neuroendocrine cell system of the gut. Loss of the putative tumor suppressor effect of the MEN1 gene is probably responsible for the development of MEN1-associated tumors. We report here a genetic study of a female MEN1 patient with the association of nodular hyperplasia of two parathyroid glands, an insulinoma, multiple duodenal gastrinomas, a prolactinoma, and a gastric carcinoid. We performed loss of heterozygosity (LOH) studies of chromosome 11 on all affected tissues except the insulinoma. Allelic losses of chromosome 11 were detected in several tumors, but the chromosomal regions of LOH were different, suggesting that different somatic mutational events are involved in the pathogenesis of these tumors. LOH of chromosome 11 was also detected in the prolactinoma of this patient, which indicates that the MEN1 gene has a tumor suppressor effect in the pituitary.- - - - - - - - - - ranking = 0.55091403998434keywords = pituitary (Clic here for more details about this article) |
10/12. Widespread neuroendocrine malignancy within the central nervous system: a diagnostic conundrum.A 75 year old female presented with a sellar tumour, and was subsequently found also to have a cauda equina tumour, a parietal dural tumour, a pontine tumour, an intradural spinal tumour, and several vertebral body tumours. Histological examination revealed a neuroendocrine tumour forming cell nests surrounded by reticulin. There was moderate nuclear pleomorphism, prominent mitoses, and focal necrosis. immunohistochemistry showed diffuse positive staining with cytokeratins, chromogranin and 5-hydroxytryptamine, and focal positive staining with S100. This case is an unusual and ultimately insoluble, diagnostic problem; however, the differential diagnoses include pituitary carcinoma, malignant paraganglioma, and atypical carcinoid.- - - - - - - - - - ranking = 0.27545701999217keywords = pituitary (Clic here for more details about this article) |
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