The Experts below are selected from a list of 855 Experts worldwide ranked by ideXlab platform
William R Sukov - One of the best experts on this subject based on the ideXlab platform.
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a cytogenetic analysis of 2 cases of phosphaturic mesenchymal tumor of mixed connective tissue type
2012Co-Authors: Rondell P Graham, Andrew L Folpe, Jennelle C Hodge, Andre M Oliveira, Kevin J Meyer, Robert B Jenkins, Franklin H Sim, William R SukovAbstract:Phosphaturic mesenchymal tumor of mixed connective tissue type is a rare, histologically distinctive mesenchymal neoplasm associated with tumor-induced osteomalacia resulting from production of the phosphaturic hormone fibroblast growth factor 23. Because of its rarity, specific genetic alterations that contribute to the pathogenesis of these tumors have yet to be elucidated. Herein, we report the abnormal karyotypes from 2 cases of confirmed phosphaturic mesenchymal tumor of mixed connective tissue type. G-banded analysis demonstrated the first tumor to have a karyotype of 46,Y,t(X;3;14)(q13;p25;q21)[15]/46XY[5], and the second tumor to have a karyotype of 46, XY,add(2)(q31),add(4)(q31.1)[2]/92,slx2[3]/46,sl,der(2)t(2;4)(q14.2;p14),der(4)t(2;4)(q14.2;p14),add(4)(q31.1)[10]/46,sdl,add(13)(q34)[4]/92,sdl2x2[1]. These represent what is, to our knowledge, the first examples of abnormal karyotypes obtained from phosphaturic mesenchymal tumor of mixed connective tissue type.
Andrew L Folpe - One of the best experts on this subject based on the ideXlab platform.
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a cytogenetic analysis of 2 cases of phosphaturic mesenchymal tumor of mixed connective tissue type
2012Co-Authors: Rondell P Graham, Andrew L Folpe, Jennelle C Hodge, Andre M Oliveira, Kevin J Meyer, Robert B Jenkins, Franklin H Sim, William R SukovAbstract:Phosphaturic mesenchymal tumor of mixed connective tissue type is a rare, histologically distinctive mesenchymal neoplasm associated with tumor-induced osteomalacia resulting from production of the phosphaturic hormone fibroblast growth factor 23. Because of its rarity, specific genetic alterations that contribute to the pathogenesis of these tumors have yet to be elucidated. Herein, we report the abnormal karyotypes from 2 cases of confirmed phosphaturic mesenchymal tumor of mixed connective tissue type. G-banded analysis demonstrated the first tumor to have a karyotype of 46,Y,t(X;3;14)(q13;p25;q21)[15]/46XY[5], and the second tumor to have a karyotype of 46, XY,add(2)(q31),add(4)(q31.1)[2]/92,slx2[3]/46,sl,der(2)t(2;4)(q14.2;p14),der(4)t(2;4)(q14.2;p14),add(4)(q31.1)[10]/46,sdl,add(13)(q34)[4]/92,sdl2x2[1]. These represent what is, to our knowledge, the first examples of abnormal karyotypes obtained from phosphaturic mesenchymal tumor of mixed connective tissue type.
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rt pcr analysis for fgf23 using paraffin sections in the diagnosis of phosphaturic mesenchymal tumors with and without known tumor induced osteomalacia
2009Co-Authors: Armita Bahrami, Sharon W Weiss, Elizabeth A Montgomery, Andrew E Horvai, Long Jin, Carrie Y Inwards, Andrew L FolpeAbstract:Phosphaturic mesenchymal tumors of the mixed connective tissue type (PMTMCT) are extremely rare, histologically distinctive neoplasms, which cause tumor-induced osteomalacia (TIO) in most cases through the elaboration of a phosphaturic hormone, fibroblast growth factor-23 (FGF23). Rarely, identical tumors without known TIO may be observed. We studied a large group of PMTMCT for expression of FGF23, using a novel reverse transcription polymerase chain reaction (RT-PCR) assay for FGF23 in formalin-fixed, paraffin-embedded tissues. Twenty-nine PMTMCT (17 with and 12 without TIO) and 23 non-PMTMCT (16 various mesenchymal tumors, including 5 chondromyxoid fibroma, 8 chondroblastoma, 1 hemangiopericytoma, 1 aneurysmal bone cyst, and 1 high grade sarcoma; 5 carcinomas; and 2 non-neoplastic tissues) were retrieved. Total RNA was extracted from formalin-fixed, paraffin-embedded sections for RT-PCR analysis. FGF23 was amplified using 3 sets of primers that spanned the intron/exon boundaries to amplify the 3 exons of FGF23 gene (140, 125, and 175 bp). The housekeeping gene phosphoglycerokinase (189 bp) was coamplified to check the RNA quality. Sixteen of 17 (94%) PMTMCT with TIO were FGF23-positive. Nine of 12 (75%) PMTMCT without TIO were FGF23-positive. Two chondromyxoid fibroma and 1 aneurysmal bone cyst were positive; all other non-PMTMCT were negative. We conclude that RT-PCR for FGF23 is a sensitive and specific means of confirming the diagnosis of PMTMCT both in patients with and without TIO. FGF23 gene expression was present in more than 90% of PMTMCT with known TIO, confirming the role of FGF23 in this syndrome. Rare FGF23-negative PMTMCT with known TIO likely express other phosphaturic hormones (eg, frizzled-related protein 4). Our finding of expression of FGF23 in 75% of histologically identical tumors without known TIO confirms the reproducibility of the diagnosis of PMTMCT, even in the absence of known Phosphaturia.
Kumarasen Cooper - One of the best experts on this subject based on the ideXlab platform.
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phosphaturic mesenchymal tumour mixed connective tissue variant without oncogenic osteomalacia
2009Co-Authors: R Winters, S Bihlmeyer, Laurence E Mccahill, Kumarasen CooperAbstract:Phosphaturic mesenchymal tumour-mixed connective tissue variant is a rare tumour classically associated with oncogenic osteomalacia. This report describes two patients with this distinct tumour type but with no evidence of the paraneoplastic syndrome.
Ian F Parney - One of the best experts on this subject based on the ideXlab platform.
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intracranial phosphaturic mesenchymal tumor mixed connective tissue variant presenting without oncogenic osteomalacia
2012Co-Authors: Regina S Bower, Wilson P Daugherty, Caterina Giannini, Ian F ParneyAbstract:BACKGROUND: Phosphaturic mesenchymal tumor, mixed connective tissue variant (PMTMCT) is a rare tumor typically occurring in soft tissues and bone, causing oncogenic (tumor-induced) osteomalacia (TIO) through secretion of the phosphaturic hormone, fibroblast growth factor-23 (FGF-23). Rare tumors identical to PMTMCT occur without known TIO. Intracranial localization of PMTMCT is extremely rare, with only two cases reported in the literature. We present a very unusual case of a patient with an intracranial PMTMCT that presented with neurologic changes without osteomalacia. CASE DESCRIPTION: A 67-year-old woman presented with progressive incontinence, apathy, and abulia after having undergone a total knee replacement 1 month earlier. Imaging disclosed a large left frontal anterior fossa mass. She underwent uncomplicated surgical resection of this tumor. Surprisingly, histopathology suggested PMTMCT. Reverse transcription polymerase chain reaction (RT-PCR) assay demonstrating FGF-23 expression in the tumor confirmed the diagnosis. Serum FGF-23 levels postoperatively were normal and she had no clinical or laboratory evidence of osteomalacia or Phosphaturia. CONCLUSION: This report should serve to alert clinicians to the possibility that PMTMCT can be included in the differential diagnosis of intracranial masses even in the absence of tumor-induced osteomalacia.
Michael T Collins - One of the best experts on this subject based on the ideXlab platform.
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characterization of fn1 fgfr1 and novel fn1 fgf1 fusion genes in a large series of phosphaturic mesenchymal tumors
2016Co-Authors: Jenchieh Lee, Michael T Collins, Chun A Changou, Rongsen Yang, Kehsung Tsai, Eric S Orwoll, Chungyen Lin, Shu Hwa Chen, Shyangrong Shih, Chenghan LeeAbstract:Characterization of FN1–FGFR1 and novel FN1–FGF1 fusion genes in a large series of phosphaturic mesenchymal tumors
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Fracture Incidence in Polyostotic Fibrous Dysplasia and the McCune-Albright Syndrome
2015Co-Authors: Pamela G Robey, Paolo Bianco, Shlomo Wientroub, Michael T CollinsAbstract:ABSTRACT: In patients with polyostotic fibrous dysplasia of bone, the peak incidence of fractures is during the first decade of life, followed by a decrease thereafter. Phosphaturia is associated with an earlier incidence and increased frequency of fractures. Introduction: Fibrous dysplasia (FD) is a disorder involving either one (monostotic) or several bones (polyostotic FD [PFD] and sometimes is associated with cafe-au-lait hyperpigmentation of the skin and one or more hyperfunc-tioning endocrinopathies (McCune-Albright syndrome [MAS]). Both PFD and MAS are often associated with Phosphaturia. Although fractures occur frequently in PFD/MAS, fracture incidence and the effect of age and co-existing metabolic abnormalities (endocrinopathy and/or Phosphaturia) on fractures are ill defined
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cinacalcet in the management of tumor induced osteomalacia
2007Co-Authors: Jordan L Geller, Azarmindokht Khosravi, Marilyn H Kelly, Mara Riminucci, John S Adams, Michael T CollinsAbstract:Both FGF-23 and PTH inhibit renal phosphate reabsorption. We treated two patients with TIO and FGF-23–mediated hypophosphatemia with cinacalcet to test the hypothesis that medicinally induced hypoparathyroidism would decrease renal phosphate wasting. Cinacalcet treatment resulted in increased renal phosphate reabsorption, allowed for a decrease in phosphate supplementation, and showed evidence of bone healing in one of the two patients. Introduction: Tumor-induced osteomalacia (TIO) is a rare, acquired disease of renal phosphate wasting, which results in hypophosphatemia and osteomalacia. It is caused by mesenchymal tumors that produce the phosphate and vitamin D–regulating hormone, fibroblast growth factor (FGF)-23. Removal of the tumor is curative, but the tumors are often difficult to locate. Medical treatment involves high doses of oral phosphate and calcitriol, but the phosphate is often poorly tolerated and leads to diarrhea. Because PTH also promotes Phosphaturia, and patients with hypoparathyroidism are hyperphosphatemic in the setting of elevated serum FGF-23, we postulated that the calcium-sensing receptor agonist, cinacalcet, which can induce hypoparathyroidism, would be an effective adjuvant in the treatment of TIO. Materials and Methods: Two subjects with presumed TIO in whom the tumor was not located after extensive testing and who did not tolerate medical therapy with phosphorus and calcitriol were treated with cinacalcet. Results: Neither treatment with phosphorus nor combined treatment with phosphorus and calcitriol had an effect on serum FGF-23 levels. Treatment with cinacalcet resulted in increased renal phosphate reabsorption and serum phosphorus and allowed for a decrease in phosphate supplementation to a dose that was tolerated. On this regimen, one patient showed significant bone healing as shown by resolution of activity on bone scan and lack of osteomalacia as assessed by histomorphometry. Conclusions: These data show that medically induced hypoparathyroidism with cinacalcet is a therapeutic option for disorders of FGF-23–mediated hypophosphatemia and that, in the absence of PTH, the phosphaturic effect of FGF-23 is decreased.