Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007095 (carcinoid)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report three cases of intrathyroidal paraganglioma. The patients were adult women without significant personal or family histories that presented with an asymptomatic thyroid nodule. The tumors were single, well-circumscribed solid masses, 2 cm in greatest diameter, located within one thyroid lobe. Microscopically, they were encapsulated and showed the typical nesting (Zellballen) pattern of paraganglioma in other sites. Two of the tumors were composed of small- to medium-sized cells with granular amphophilic cytoplasm, and the third consisted of relatively large cells having a similar staining quality. Immunohistochemically, all tumors showed positivity for neuron-specific enolase, chromogranin A, and synaptophysin. S-100 protein-positive sustentacular cells were demonstrated in each case. Negative staining for epithelial markers, thyroglobulin, carcinoembryonic antigen, calcitonin, calcitonin gene-related peptide, serotonin, vimentin, and Congo red excluded other tumors that were considered in the differential diagnosis, such as medullary carcinoma, hyalinizing trabecular adenoma, atypical follicular adenoma, Hurthle-cell neoplasm, and metastatic carcinoid tumor. The patients were alive and well without evidence of recurrent disease at the time of the last follow-up. The previous literature on these tumors is discussed. We conclude that intrathyroidal paraganglioma exists and that this tumor can be distinguished from other similar-appearing neoplasms in this organ.
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PMID:Thyroid paraganglioma: a clinicopathologic and immunohistochemical study of three cases. 923 30

Thirty-two cases of so-called sclerosing hemangioma of the lung observed by light microscopy were further studied by electron microscopy and/or immunohistochemistry. Three histologic patterns were seen: hemangioma-like, papillary, and solid. The only significant component representing the nature of the lesion is characteristic round cells within the stroma in all these patterns, whereas the surface cells lining the papillary projections or cystic spaces are normal or are hyperplastic bronchioloalveolar cells with a few neuroendocrine cells. Immunohistochemical findings showed that the "stromal cells" (tumor cells) were positive for neuroendocrine markers, namely, chromogranin A (19 of 22 cases), neuron-specific enolase (24 of 24), synaptophysin (six of 10), adrenocorticotropic hormone (14 of 15), growth hormone (14 of 15), calcitonin (11 of 15), and gastrin (11 of 14). Besides, some tumor cells were positive for epithelial membrane antigen (four of four), carcinoembryonic antigen (one of four), and vimentin (one of one). All tumor cells were negative for polyclonal antikeratin antibody (25 cases), AE1 (one case), and AE3 (one case). However, in contrast to the "stromal cells," the surface cells of the cystic spaces stained positively for keratin (25 of 25 cases), AE1 (one of one), AE3 (one of one), epithelial membrance antigen (four of four), and carcinoembryonic antigen (four of four); only a few of them expressed neruoendocrine markers. Both surface and tumor cells were negative for factor VIII-related antigen (25 cases), CD31 (one case), and alpha1-antitrypsin (25 cases). Ten cases further studied by electron microscopy and six examined by ultrastructural morphometry showed that the surface cells were mainly type 2 pneumocytes containing many lamellar bodies in the cytoplasm. Lying among them, neuroendocrine cells were occasionally seen. The stromal tumor cells had no lamellar body, but dense core granules (neurosecretory granules) and microtubules. In six cases, 92.3% (345 of 374) of tumor cells contained neurosecretory granules, which were pleomorphic and 73 to 1056 nm in diameter (mean, 302 nm). Two to 193 (mean, 12) neurosecretory granules were found in each tumor cell. Both immunohistochemical findings and ultrastructural evidence indicate that so-called sclerosing hemangioma of the lung is a benign lesion composed of neoplastic neuroendocrine cells with areas of sclerosis. A suggested name for this tumor is benign neuroendocrine tumor of the lung. The differentiation between this tumor and papillary adenoma, bronchioloalveolar carcinoma, or carcinoid tumor of the lung is discussed.
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PMID:Neuroendocrine differentiation in 32 cases of so-called sclerosing hemangioma of the lung: identified by immunohistochemical and ultrastructural study. 998 55

To determine the neuroendocrine (NE) features of thymic epithelial tumor, immunohistochemistry and electron microscopy studies were performed on eight NE tumors (thymic carcinoids) and 26 non-NE tumors (nine thymic carcinomas, five atypical thymomas, and 12 thymomas other than lymphocytic thymoma). Immunohistochemical studies were performed with antibodies against general markers for NE cells (synaptophysin, alpha subunit of a guanine nucleotide-binding protein, Go, and small-cell lung carcinoma cluster 1 antigen), and a broad panel of antibodies for hormonal substances. Thymic carcinoid showed synchronous diffuse immunoreactivity for the three NE markers and contained cells that were positive for a variety of hormonal products: human chorionic gonadotropin (hCG) alpha-subunit (eight of eight), hCG beta-subunit (three of eight), adrenocorticotropic hormone (ACTH) (three of eight), calcitonin (two of eight), calcitonin gene-related peptide (two of eight), and serotonin (one of eight). Conversely, although positivity for NE markers was neither synchronous nor diffuse in non-NE tumors, seven of nine thymic carcinomas, three of five atypical thymomas (focal or dispersed distribution), and none of the five thymomas were positive for at least two of these NE markers. A small number of neoplastic cells were positive for hCGalpha-subunit or ACTH in three thymic carcinomas and one atypical thymoma. Ultrastructurally, dense core granules (DCG) were much more frequent in thymic carcinoid, but several DCG-like granules were identified in 12 of 13 non-NE tumors with or without immunoexpression of NE markers. The presence of focal or dispersed NE cells in thymic carcinoma and atypical thymoma may reflect multidirectional differentiation within the tumor, which, like cytological atypia, epithelial CD5 expression, and lack of immature T cell infiltration, may be another feature of this group at thymic tumors.
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PMID:Neuroendocrine differentiation in thymic epithelial tumors with special reference to thymic carcinoma and atypical thymoma. 956 81

Carcinoid tumors having distinct paranuclear clear zones seen on hematoxylin and eosin stain are rare and few cases have been reported in the literature. Furthermore, primary hepatic carcinoid tumor with a paranuclear clear zone is extremely rare. We recently experienced a case from a 48-year-old man who presented a large single mass, 12 cm in largest diameter, in the right lobe of the liver. Histologically, the tumor revealed characteristic organoid pattern with central hyaline degeneration. The tumor cells had a prominent paranuclear vacuolated dear zone. On immunohistochemistry, tumor cells were diffusely positive for synaptophysin and focally stained for chromogranin A. Ultrastructural examination revealed paranuclear aggregation of intermediate filaments and membrane-bound clear vesicles, which corresponded to the paranuclear vacuolated clear zone.
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PMID:Primary hepatic carcinoid tumor with a paranuclear clear zone: a case report. 968 13

This report describes a case of atypical carcinoid of the larynx with metastatic tumor to cervical lymph nodes showing features similar to paraganglioma. Immunohistochemically, both the primary and metastatic tumor were positive for epithelial membrane antigen, cytokeratin, neuron-specific enolase, chromogranin, synaptophysin, calcitonin and carcinoembryonic antigen. The sustentacular cells in pseudo-cell ball ("Zellballen") formations were shown by a positive S-100 marker. Electron microscopic analysis revealed numerous neuroendocrine granules measuring 150-250 nm in diameter. Clinical features, histological appearance, histochemical, immunohistochemical and ultrastructural findings, as well as differential diagnosis are discussed.
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PMID:Unusual features of metastatic atypical carcinoid of the larynx. 969 30

Immunohistochemical evidence of neuroendocrine differentiation in the form of reactivity for synaptophysin, neuron-specific enolase, and/or chromogranin was found in 11 of 19 (58%) thymic carcinomas having the typical morphologic features of that tumor type. Four of these 19 cases were studied ultrastructurally, and neuroendocrine-type cytoplasmic dense-core granules were found in two. In contrast, 84 thymomas were negative for these markers, except for a focal immunoreactivity for neuron-specific enolase in areas of medullary differentiation in half of the lymphocyte-rich tumors. The results of this study show that in the thymus, similar to most other organs, neuroendocrine differentiation is not limited to tumors with an identifiable neuroendocrine appearance in hematoxylin-eosin-stained slides, such as carcinoid tumor and small cell carcinoma, but rather that it represents a common event shared by the major types of malignant epithelial tumors of that organ.
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PMID:Neuroendocrine differentiation is a common feature of thymic carcinoma. 973 37

Carcinoid tumors are potentially malignant neoplasms that arise in various body sites, including the lung and gastrointestinal tract. Those that appear cytologically atypical are more likely to behave aggressively than more typical carcinoid tumors. However, in the absence of cytological atypia or large tumor size, it is difficult to predict the biology of an individual tumor, because some lesions metastasize, whereas others do not. This study had four aims: (1) To study the expression pattern of p53, Ki-67, NCAM, and S-100 in carcinoid tumors and to relate these expression patterns to classical histopathologic features and to tumor location. (2) To identify nonhistological markers that might more accurately predict the early behavior of carcinoid tumors. (3) To determine whether sustentacular cells are present in carcinoid tumors arising in tissues derived from different embryological derivatives. (4) To determine the synaptophysin and chromogranin immunoreactivity in neuroendocrine tumors arising in various locations. The immunostaining reactions were quantitatively scored by three observers. Only 3 of the 39 tumors (all histologically atypical) were strongly positive for Ki-67; two of these were also strongly p53 immunoreactive. NCAM immunostaining differed according to the site of origin: 76.5% of foregut lesions, 58% of the midgut lesions, and 20% of hindgut lesions were positive. S-100 immunostaining ranged from 41% in foregut lesions to 50% in both the hindgut- and midgut-derived tumors. S-100-positive sustentacular cells were present in 20.5% of carcinoid tumors. All tumors stained with antibodies against synaptophysin. In contrast, 100% of midgut, 60% of hindgut, and 88% of foregut tumors were chromogranin positive. Carcinoid tumors tend to have low proliferative rates. p53 immunostaining tends to be strongly positive in tumors that are histologically atypical, but it is negative in typical carcinoid tumors arising in the gastrointestinal tract and lungs. Immunostaining reactions with antibodies to NCAM, S-100, and chromogranin differ depending on the site of origin. Synaptophysin stains 100% of carcinoid tumors regardless of their site of origin. In contrast, antibodies to chromogranin fail to stain 40% of hindgut tumors and 12% of foregut carcinoid tumors. S-100-positive sustentacular cells are present in foregut and midgut tumors but not in hindgut tumors.
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PMID:Immunohistologic analysis of gastrointestinal and pulmonary carcinoid tumors. 974 17

The diagnosis of adenocarcinoid (mucinous/goblet cell carcinoid) is usually unexpected by both clinicians and pathologists. We report here the case of a 74-year-old man with gastric lymphoma (B-cell MALToma) diagnosed by endoscopy, who was found on exploratory laparotomy also to have extensive intraabdominal involvement by adenocarcinoid, arising from the ileum and/or appendix. The patient died two years after diagnosis with bladder outlet and small bowel obstruction due to diffuse metastases. In addition to mucin positivity, immunohistochemical stains demonstrated the tumor to be positive for chromogranin, synaptophysin, serotonin, gastrin, and glucagon. Of histogenetic interest, some individual neoplastic cells appeared to be positive for both mucin and chromogranin, and this was confirmed by the electron microscopic finding of microvilli, intracytoplasmic mucin droplets, and neurosecretory granules involving the same neoplastic cells. This also appears to be the first reported case of adenocarcinoid associated with lymphoma and demonstration of histochemical/immunohistochemical and ultrastructural evidence of cellular components with dual mucinous adenocarcinoma and neuroendocrine features, and the second reported case to have prostatic metastases.
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PMID:Adenocarcinoid of ileum and appendix, incidentally discovered during exploratory laparotomy for gastric MALT lymphoma, with subsequent diffuse prostatic metastases: report of a case with light, immunohistochemical, and electron microscopic studies. 995 28

Seven cases of spindle-cell neuroendocrine carcinomas (carcinoid tumors) of the thymus are presented. The patients were three women and four men between the ages of 26 and 74 years (median age, 50 yr). The lesions presented as large anterior mediastinal masses on radiographic examination and were treated by surgical excision. Grossly, the tumors were tan-brown and well circumscribed but encapsulated, and they measured from 2 to 15 cm in greatest diameter. Histologically, they were characterized by a dense proliferation of spindle cells that focally adopted a vaguely organoid pattern, with discrete nests of tumor cells separated by thin fibrovascular septa. Mitotic figures were present in all of our cases and ranged from 2 to 8 per 10 high power fields. Focal areas of necrosis were also present in all of the cases. Immunohistochemical studies performed in six cases showed positive staining for chromogranin in five cases, synaptophysin and keratin in four, and Leu 7 in three. Clinical follow-up showed that two patients died of their tumors 6 and 11 years after diagnosis; one was alive 8 years after diagnosis. Spindle-cell neuroendocrine carcinomas of the thymus (spindle-cell thymic carcinoids) should be considered in the differential diagnosis of spindle-cell neoplasms of the anterior mediastinum. Because of their aggressive clinical behavior, it is important to separate them from the other benign or low-grade spindle-cell tumors that are more common at this location.
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PMID:Spindle-cell neuroendocrine carcinomas of the thymus (spindle-cell thymic carcinoid): a clinicopathologic and immunohistochemical study of seven cases. 1039 34

We describe a case of a rare variant of a rectal carcinoid tumor that showed mucous gland differentiation accompanied by a lymph node metastasis with a histological appearance similar to that of the primary site. The tumor consisted of a typical argyrophilic carcinoid component and of goblet cell glands. The carcinoid component was positive for neuron-specific enolase, chromogranin A and synaptophysin. The goblet cells stained positively with periodic acid-Schiff (PAS) and alcian blue, and expressed carcinoembryonic antigen, but were negative for neuroendocrine markers. This case suggests that carcinoid tumor can differentiate towards mucus glands, which can also be found in the metastatic site.
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PMID:Rectal adenocarcinoid with lymph node metastasis. 1046 1


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