1/34. A case of renal metanephric adenoma: histologic, immunohistochemical and cytogenetic analyses.BACKGROUND: A unique case of metanephric adenoma of the left kidney is reported in a 61-year-old woman presenting with an incidental renal mass on ultrasonography. methods/RESULTS: On radiographic examination, the presence of hypovascular renal cell carcinoma was suspected and left radical nephrectomy was performed. The resected tumor, measuring 4.9 x 4.7 x 4.5 cm, was well-circumscribed and solid and its cut surface was tan-pink with foci of focal hemorrhage and cystic change. Microscopically, the tumor was composed of uniformly small acini with hyperchromatic round nuclei. Some acini were dilated and occasionally contained glomeruloid-like bodies and psamoma bodies. Immunohistochemically, tumor cells showed positive immunoreaction for vimentin, cytokeratin and Leu 7. Cytogenetically, the tumor did not show numerical aberrations of chromosome 7 or 17 by fluorescence in situ hybridization. CONCLUSIONS: The patient is alive without recurrence or metastasis 4 years after surgery. Metanephric adenoma must be differentiated from other renal tumors, particularly Wilms' tumor or low-grade renal cell carcinoma. Immunohistochemical and cytogenetic analysis may be helpful in difficult cases.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/34. Involvement of the HMGI(Y) gene in a microfollicular adenoma of the thyroid.Follicular thyroid adenomas are epithelial tumors characterized by subgroups with specific chromosomal aberrations. Here we present a case with translocation t(1;6)(p35;p21). In 1p35 and 6p21, two genes of the high-mobility group of proteins are located. With P1-derived Artificial Chromosome (PACs) derived from the HMG17 gene located at 1p35 and HMGI(Y) located at 6p21, fluorescence in situ hybridization was performed. The breakpoints were located distal to HMG17 and proximal to HMGI(Y), but no rearrangement of the genes was shown by FISH. However, an overexpression of the HMGI(Y) gene was detected by RT-PCR as well as by immunohistochemistry techniques. This suggests a breakpoint in the proximity of the HMGI(Y) deregulating HMGI(Y) gene expression, a situation found in a variety of human benign mesenchymal tumors with involvement of chromosome band 6p21.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/34. Pituitary somatotroph adenoma producing growth hormone (GH)-releasing hormone (GHRH) with an elevated plasma GHRH concentration: a model case for autocrine and paracrine regulation of GH secretion by GHRH.An acromegalic patient with a pituitary somatotroph adenoma associated with an extremely elevated plasma GHRH concentration is presented. The preoperatively high concentration of plasma GHRH returned to the normal level after successful removal of the adenoma. GHRH production and GHRH gene expression were confirmed in the adenoma by studies including immunohistochemistry and in situ hybridization. Expression of GHRH receptor messenger ribonucleic acid was verified by in situ hybridization. Immunohistochemical double staining for GH and GHRH revealed their colocalization in single adenoma cells. These findings confirmed the autocrine or paracrine regulation of GH production by endogenous GHRH from the adenoma cells. GHRH synthesis in the pituitary gland has recently been demonstrated, however, there have been no previous reports of a GHRH-producing pituitary somatotroph adenoma associated with an elevated plasma GHRH concentration. The existence of this GHRH-producing adenoma suggests a possible role of locally generated GHRH in the progression of somatotroph adenomas, i.e. the monoclonally established somatotroph adenomas develop further under the influence of locally produced GHRH. The demonstration of GHRH production by this somatotroph adenoma is of importance in clarifying the autocrine or paracrine regulation of GH production and the progression of human somatotroph adenomas.- - - - - - - - - - ranking = 2keywords = hybridization (Clic here for more details about this article) |
4/34. Translocations (X;10)(p22;q24) and (1;10)(q21;q11) in a follicular adenoma of the thyroid without apparent involvement of the RET protooncogene.We report here the cytogenetic analysis of a follicular adenoma of the thyroid which revealed an abnormal clone with a t(X;10)(p22;q24) and a t(1;10)(q21;q11) together with normal cells. fluorescence in situ hybridization (FISH) with YACs 273E3 and 344H4, which are located on 10q11.2 and are specific for the RET protooncogene, showed no abnormalities. It would therefore appear that this gene is not involved in the particular tumor, as has been reported in a number of papillary thyroid carcinomas. Several chromosomal aberrations have been suggested as been specific for follicular thyroid adenoma. However, until now, only a few such cases have been reported which involve structural abnormalities of chromosomes 10q11.2 and 10q24. We believe this to be the first report of a follicular thyroid adenoma with a t(X;10)and a t(1;10).- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/34. Metastatic metanephric adenoma in a child.Metanephric adenoma is a recently characterized renal tumor that generally occurs in adults and has an excellent prognosis. To date, only one atypical metanephric adenoma has been reported to metastasize. The authors report a case of typical metanephric adenoma that arose in the left kidney of a 7-year-old girl that was associated with metastases to the para-aortic, hilar, and aortic bifurcation lymph nodes. The tumor was 9.5 cm and was composed entirely of epithelial elements arranged in tubules, short papillae, and glomeruloid bodies with scattered psammoma bodies. No atypia and only rare mitotic activity were present. Immunohistochemically, the tumor was negative for epithelial membrane antigen, negative for keratin AE1, and focally positive for both keratin CAM5.2 and cytokeratin 7. Tumor cytogenetics revealed a normal diploid karyotype, and disomy of chromosomes 7 and 17 was confirmed by fluorescence in situ hybridization. The authors conclude that tumors with histologic, immunohistochemical, and genetic features characteristic of typical metanephric adenoma can present with metastatic disease.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/34. Prolactin-producing pituitary adenoma and carcinoma with neuronal components--a metaplastic lesion.Recent studies indicate that cells of various epithelial tumors are capable of transformation to neurons. Observing both neurons and neuropil in two prolactin-producing adenohypophyseal tumors, one benign and one malignant, we sought to assess their cellular differentiation, the presence of nerve growth factor receptor, and expression of the dopamine receptor gene using immunocytochemistry, electron microscopy, and in situ hybridization. light and electron microscopy clearly revealed cells morphologically transitional between adenoma/carcinoma cells and neurons. Large neurons lacked proliferative activity. neurons in varying number showed immunoreactivity for pituitary hormones including prolactin, growth hormone and alpha subunit in the adenoma and prolactin alone in the carcinoma. The distribution of nerve growth factor receptor staining was similar. In both tumors, in situ hybridization showed mRNAs for prolactin and dopamine receptor within adenohypophyseal cells and neurons. Our results indicate that the occurrence of neurons and neuropil in growth hormone and prolactin-producing pituitary tumors appears to be the result of metaplasia. The process is not limited to benign tumors and may be due to the production of tropic substances by the adenohypophysial cells, which by paracrine/autocrine mechanisms result in transformation of adenoma cells to nerve cells.- - - - - - - - - - ranking = 2keywords = hybridization (Clic here for more details about this article) |
7/34. Pituitary macroadenoma in a 5-year-old: an early expression of multiple endocrine neoplasia type 1.multiple endocrine neoplasia type 1 (MEN 1) is associated with parathyroid, enteropancreatic, pituitary, and other tumors. The MEN1 gene, a tumor suppressor, is located on chromosome 11. Affected individuals inherit a mutated MEN1 allele, and tumorigenesis in specific tissues follows inactivation of the remaining MEN1 allele. MEN 1-associated endocrine tumors usually become clinically evident in late adolescence or young adulthood, as high levels of PTH, gastrin, or PRL. Because each of these tumors can usually be controlled with medications and/or surgery, MEN 1 has been regarded mainly as a treatable endocrinopathy of adults. Unlike in MEN 2, early testing of children in MEN 1 families is not recommended. We report a 2.3-cm pituitary macroadenoma in a 5-yr-old boy with familial MEN 1. He presented with growth acceleration, acromegaloid features, and hyperprolactinemia. We tested systematically to see whether his pituitary tumor had causes similar to or different from a typical MEN 1 tumor. Germ line dna of the propositus and his affected relatives revealed a heterozygous point mutation in the MEN1 gene, which leads to a His139Asp (H139D) amino acid substitution. The patient had no other detectable germ-line mutations on either MEN1 allele. dna sequencing and fluorescent in situ hybridization with a MEN1 genomic dna sequence probe each demonstrated one copy of the MEN1 gene to be deleted in the pituitary tumor and not in normal dna, proving MEN1 "second hit" as a tumor cause. Gsalpha mutation, common in nonhereditary GH-producing tumors, was not detected in this tumor. We conclude that this pituitary macroadenoma showed molecular genetic features of a typical MEN 1-associated tumor. This patient represents the earliest presentation of any morbid endocrine tumor in MEN 1. A better understanding of early onset MEN 1 disease is needed to formulate recommendations for early MEN 1 genetic testing.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/34. monosomy of chromosome 11 in pituitary adenoma in a patient with familial multiple endocrine neoplasia type 1.multiple endocrine neoplasia type 1 (MEN 1) represents an endocrine syndrome characterized by complex pituitary, parathyroid and pancreatic neoplasia. loss of heterozygosity of the specific region 11q13 has been reported in several tumours from patients with MEN 1 inherited disorder. We present a case of a young patient with familial MEN 1 syndrome with a pituitary adenoma exhibiting monosomy of chromosome 11. The patient presented with a large and rapidly growing pituitary adenoma associated with markedly elevated serum PRL levels, progressive bilateral visual loss and hydrocephalus. The resected adenoma was chromophobic, mainly PRL-producing and to a lesser degree immunoreactive for GH. fluorescence in situ hybridization (FISH) using an alpha-satellite centromeric probe detected loss of one chromosome 11 copy in almost all pituitary adenoma cells. Clinical and biochemical studies revealed parathyroid hyperplasia and MRI studies detected a pancreatic tumour in addition to the pituitary adenoma. To our knowledge this is the first study reporting monosomy 11 in pituitary adenoma in a patient associated with familial MEN 1 syndrome.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
9/34. ACTH silent adenoma shrinking under cabergoline.OBJECTIVES: The authors present a case report that proposes the use of cabergoline treatment in silent ACTH adenoma, an unusual member of the heterogeneous group of the so-called clinically non-functioning pituitary adenomas. DESIGN: Following the clinical and radiological improvement of a recurrent silent ACTH adenoma in a 77-year-old patient treated with cabergoline (0.5 mg every 2 days for 2 years), in vitro studies of the original tumor were performed. methods: The original tumor from the patient was studied by in situ hybridization and dopamine D2 receptor autoradiography. It was compared with four macroprolactinomas and two macroadenomas from patients with Cushing's disease. RESULTS: The D2 receptor mRNA signal of the reported case was intense and of the same order of magnitude as that observed in control prolactinomas. dopamine D2 receptor autoradiography was twice that of control corticotroph adenomas and was close to that observed in prolactinomas. CONCLUSIONS: This is the first description of an in vivo shrinkage of an ACTH silent adenoma under cabergoline. We demonstrate in vitro, the presence of D2 receptors in the primitive tumor in concentrations similar to those found in control prolactinomas. These results suggest that therapeutic trials with cabergoline might be undertaken in recurring cases of ACTH silent tumors and more generally, non-functioning pituitary adenomas.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
10/34. Metastatic metanephric adenoma with foci of papillary carcinoma in a child: a combined histologic, immunohistochemical, and FISH study.We report an example of metastatic metanephric adenoma containing foci of papillary carcinoma in the primitive tumor arising in the left kidney of an 11-year-old girl. histology revealed a monomorphous population of small cells with bland cytology arranged in pseudoglandular, tubular, papillary, and glomeruloid structures with frequent psammoma bodies. Intermixed there were foci of and small cavities lined by larger cells with eosinophilic cytoplasm and larger nuclei with small nucleoli. A regional lymph node contained metastatic deposits with the former histologic pattern. By immunohistochemistry the small cells were negative for carcinoembryonic antigen (CEA) and keratin 7 while these antibodies reacted positively in the larger cells. A fluorescent in-situ hybridization (FISH) study for chromosome 17 in imprints from the primitive tumor revealed 3 signals in about 10% of the nuclei while the rest was disomic. Disaggregated cells from the metastatic lymph node consistently revealed 2 signals for chromosomes 7, 16, and l7. histology of the primitive tumor resembled the epithelial component of the so-called metanephric adenofibroma while the metastatic lymph node exhibited histologic and FISH genomic features of metanephic adenoma. Int J Surg Pathol 9(3):241-247, 2001- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
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