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Rebecca S Mason - One of the best experts on this subject based on the ideXlab platform.
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diagnosis of a patient with Oncogenic Osteomalacia using a phosphate uptake bioassay of serum and magnetic resonance imaging
European Journal of Endocrinology, 2001Co-Authors: Anne E Nelson, Bruce G Robinson, Rebecca S Mason, Jeremy J Hogan, Kenneth B Jonsson, Tobias E Larsson, Erin A Martin, Hakan Ahlstrom, Gunnar Astrom, Lars WibellAbstract:A previously healthy man with no family history of fractures presented with muscle pain, back pain and height loss. Investigations revealed hypophosphataemia, phosphaturia, undetectable serum 1,25-dihydroxyvitamin D and severe Osteomalacia on bone biopsy, suggestive of a diagnosis of Oncogenic Osteomalacia. Thorough physical examination did not locate a tumour. Support for the diagnosis was obtained by detection of phosphate uptake inhibitory activity in a blinded sample of the patient's serum using a renal cell bioassay. On the basis of detection of this bioactivity, a total body magnetic resonance (MR) examination was performed. A small tumour was located in the right leg. Removal of the tumour resulted in the rapid reversal of symptoms and the abnormal biochemistry typical of Oncogenic Osteomalacia. Inhibitory activity was also demonstrated using the bioassay in serum from two other patients with confirmed or presumptive Oncogenic Osteomalacia, but not in serum from two patients with hypophosphataemia of other origin. This is the first case to be reported in which the diagnosis of Oncogenic Osteomalacia was assisted by demonstration of inhibitory activity of the patient's serum in a renal cell phosphate bioassay that provided an impetus for total body MR imaging.
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tumor expression studies indicate that hem 1 is unlikely to be the active factor in Oncogenic Osteomalacia
Bone, 1998Co-Authors: Anne E Nelson, Bruce G Robinson, Rebecca S Mason, Jeremy J Hogan, Terrence H DiamondAbstract:Abstract HEM-1 was isolated as a putative factor responsible for Oncogenic Osteomalacia by Kumar et al. (Proc Assoc Am Phys 107:296–305; 1995). The cDNA was identified on the basis of PTH-like immunoreactivity; however, no studies have been reported of the expression of HEM-1 mRNA in Oncogenic Osteomalacia tumors. In this study, expression of HEM-1 mRNA was investigated in two Oncogenic Osteomalacia tumors and in a series of normal tissues. An HEM-1 PCR product was amplified from a cDNA library from one of the tumors, with six base changes identified, as compared with the published sequence. No expression was detected, however, in the Oncogenic Osteomalacia tumors either by Northern blot analysis or by reverse transcriptase PCR. This indicates that, although a region of HEM-1 sequence is present in the tumor cell cDNA library, any HEM-1 expression must be at very low levels. It is unlikely, therefore, that the HEM-1 product is the active factor responsible for Oncogenic Osteomalacia. In the normal tissues examined, human placenta, fibroblasts, parathyroid gland, liver, fetal bone, and rat kidney cortex, HEM-1 mRNA was not detected, suggesting that it does not have a physiological role in these tissues.
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Oncogenic Osteomalacia is there a new phosphate regulating hormone
Clinical Endocrinology, 1997Co-Authors: Anne E Nelson, Bruce G Robinson, Rebecca S MasonAbstract:Oncogenic Osteomalacia is a syndrome associated with rare, usually mesenchymal tumours, which is characterized by hypophosphataemia, phosphaturia and low concentrations of 1,25-dihydroxyvitamin D. The reversal of clinical and biochemical abnormalities following removal of the tumour, indicates it is the source of a humoral factor that is responsible for these abnormalities. It has been demonstrated that the humoral factor inhibits renal phosphate uptake and reduces 1,25-dihydroxyvitamin D production. Although there is evidence that it may act via parathyroid hormone/parathyroid hormone-related peptide receptors and may be a peptide, the factor has not yet been identified, nor has its relationship to factors involved in X-linked hypophosphataemic rickets been established. We propose unifying hypotheses for the pathogenesis of Oncogenic Osteomalacia and X-linked hypophosphataemic rickets which involve defects in the PEX gene. These hypotheses do not fully explain all the available data and it remains possible that hormone(s) with little or no role in X-linked hypophosphataemic rickets may be responsible for Oncogenic Osteomalacia.
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characteristics of tumor cell bioactivity in Oncogenic Osteomalacia
Molecular and Cellular Endocrinology, 1996Co-Authors: Anne E Nelson, Heeja J Namkung, J Patava, Margaret Wilkinson, Andy C M Chang, Roger R Reddel, Bruce G Robinson, Rebecca S MasonAbstract:Abstract Oncogenic Osteomalacia is a condition where renal phosphate wasting occurs causing defective mineralisation, in the presence of a tumor. Cultures of cells were established from a hemangiopericytoma resected from a patient with Oncogenic Osteomalacia. Conditioned media from the cells inhibited phosphate uptake in opossum kidney cells and stimulated production of cAMP in rat osteosarcoma cells, a standard parathyroid hormone (PTH)-like assay. This cAMP stimulation was suppressed by the PTH analogue, 3–34 bPTH and also by heat and trypsin treatment of the media. Tests of conditioned media for PTH and parathyroid hormone related protein (PTHrP) immunoreactivity were negative, however, and no hybridisation to probes for PTH, PTHrP or human stanniocalcin was detected in tumor cell RNA on Northern blot. These data support the hypothesis that tumors responsible for Oncogenic Osteomalacia produce a humoral substance that reduces renal phosphate reabsorption and provide evidence that the factor may act via PTH/PTHrP receptors.
Anne E Nelson - One of the best experts on this subject based on the ideXlab platform.
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fibroblast growth factor 23 a new clinical marker for Oncogenic Osteomalacia
The Journal of Clinical Endocrinology and Metabolism, 2003Co-Authors: Anne E Nelson, Roderick Clifton Bligh, Michiko Mirams, Anthony J Gill, Amy Y M Au, Adele Clarkson, Harald JüppnerAbstract:The phosphate-wasting condition, Oncogenic Osteomalacia, is problematic to diagnose and manage clinically due to difficulty in locating the causative tumor. Fibroblast growth factor 23 (FGF23) has recently been implicated in the pathogenesis of Oncogenic Osteomalacia. In this case the patient presented with clinical features typical of Oncogenic Osteomalacia. Removal of an angiolipoma from the thigh did not correct the clinical or biochemical abnormalities. Subsequent identification and removal of a benign giant cell tumor in the pubic ramus, however, did result in normalization of his symptoms and signs. Positive staining for FGF23 protein by immunohistochemistry was demonstrated in the giant cell tumor, but not in the angiolipoma. The serum concentration of FGF23 was elevated in preoperative serum, then normalized after removal of the giant cell tumor. Expression of both FGF23 mRNA and protein was demonstrated in the giant cell tumor tissue, and FGF23 mRNA expression and renal phosphate uptake inhibitor...
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diagnosis of a patient with Oncogenic Osteomalacia using a phosphate uptake bioassay of serum and magnetic resonance imaging
European Journal of Endocrinology, 2001Co-Authors: Anne E Nelson, Bruce G Robinson, Rebecca S Mason, Jeremy J Hogan, Kenneth B Jonsson, Tobias E Larsson, Erin A Martin, Hakan Ahlstrom, Gunnar Astrom, Lars WibellAbstract:A previously healthy man with no family history of fractures presented with muscle pain, back pain and height loss. Investigations revealed hypophosphataemia, phosphaturia, undetectable serum 1,25-dihydroxyvitamin D and severe Osteomalacia on bone biopsy, suggestive of a diagnosis of Oncogenic Osteomalacia. Thorough physical examination did not locate a tumour. Support for the diagnosis was obtained by detection of phosphate uptake inhibitory activity in a blinded sample of the patient's serum using a renal cell bioassay. On the basis of detection of this bioactivity, a total body magnetic resonance (MR) examination was performed. A small tumour was located in the right leg. Removal of the tumour resulted in the rapid reversal of symptoms and the abnormal biochemistry typical of Oncogenic Osteomalacia. Inhibitory activity was also demonstrated using the bioassay in serum from two other patients with confirmed or presumptive Oncogenic Osteomalacia, but not in serum from two patients with hypophosphataemia of other origin. This is the first case to be reported in which the diagnosis of Oncogenic Osteomalacia was assisted by demonstration of inhibitory activity of the patient's serum in a renal cell phosphate bioassay that provided an impetus for total body MR imaging.
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tumor expression studies indicate that hem 1 is unlikely to be the active factor in Oncogenic Osteomalacia
Bone, 1998Co-Authors: Anne E Nelson, Bruce G Robinson, Rebecca S Mason, Jeremy J Hogan, Terrence H DiamondAbstract:Abstract HEM-1 was isolated as a putative factor responsible for Oncogenic Osteomalacia by Kumar et al. (Proc Assoc Am Phys 107:296–305; 1995). The cDNA was identified on the basis of PTH-like immunoreactivity; however, no studies have been reported of the expression of HEM-1 mRNA in Oncogenic Osteomalacia tumors. In this study, expression of HEM-1 mRNA was investigated in two Oncogenic Osteomalacia tumors and in a series of normal tissues. An HEM-1 PCR product was amplified from a cDNA library from one of the tumors, with six base changes identified, as compared with the published sequence. No expression was detected, however, in the Oncogenic Osteomalacia tumors either by Northern blot analysis or by reverse transcriptase PCR. This indicates that, although a region of HEM-1 sequence is present in the tumor cell cDNA library, any HEM-1 expression must be at very low levels. It is unlikely, therefore, that the HEM-1 product is the active factor responsible for Oncogenic Osteomalacia. In the normal tissues examined, human placenta, fibroblasts, parathyroid gland, liver, fetal bone, and rat kidney cortex, HEM-1 mRNA was not detected, suggesting that it does not have a physiological role in these tissues.
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Oncogenic Osteomalacia is there a new phosphate regulating hormone
Clinical Endocrinology, 1997Co-Authors: Anne E Nelson, Bruce G Robinson, Rebecca S MasonAbstract:Oncogenic Osteomalacia is a syndrome associated with rare, usually mesenchymal tumours, which is characterized by hypophosphataemia, phosphaturia and low concentrations of 1,25-dihydroxyvitamin D. The reversal of clinical and biochemical abnormalities following removal of the tumour, indicates it is the source of a humoral factor that is responsible for these abnormalities. It has been demonstrated that the humoral factor inhibits renal phosphate uptake and reduces 1,25-dihydroxyvitamin D production. Although there is evidence that it may act via parathyroid hormone/parathyroid hormone-related peptide receptors and may be a peptide, the factor has not yet been identified, nor has its relationship to factors involved in X-linked hypophosphataemic rickets been established. We propose unifying hypotheses for the pathogenesis of Oncogenic Osteomalacia and X-linked hypophosphataemic rickets which involve defects in the PEX gene. These hypotheses do not fully explain all the available data and it remains possible that hormone(s) with little or no role in X-linked hypophosphataemic rickets may be responsible for Oncogenic Osteomalacia.
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characteristics of tumor cell bioactivity in Oncogenic Osteomalacia
Molecular and Cellular Endocrinology, 1996Co-Authors: Anne E Nelson, Heeja J Namkung, J Patava, Margaret Wilkinson, Andy C M Chang, Roger R Reddel, Bruce G Robinson, Rebecca S MasonAbstract:Abstract Oncogenic Osteomalacia is a condition where renal phosphate wasting occurs causing defective mineralisation, in the presence of a tumor. Cultures of cells were established from a hemangiopericytoma resected from a patient with Oncogenic Osteomalacia. Conditioned media from the cells inhibited phosphate uptake in opossum kidney cells and stimulated production of cAMP in rat osteosarcoma cells, a standard parathyroid hormone (PTH)-like assay. This cAMP stimulation was suppressed by the PTH analogue, 3–34 bPTH and also by heat and trypsin treatment of the media. Tests of conditioned media for PTH and parathyroid hormone related protein (PTHrP) immunoreactivity were negative, however, and no hybridisation to probes for PTH, PTHrP or human stanniocalcin was detected in tumor cell RNA on Northern blot. These data support the hypothesis that tumors responsible for Oncogenic Osteomalacia produce a humoral substance that reduces renal phosphate reabsorption and provide evidence that the factor may act via PTH/PTHrP receptors.
Bruce G Robinson - One of the best experts on this subject based on the ideXlab platform.
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diagnosis of a patient with Oncogenic Osteomalacia using a phosphate uptake bioassay of serum and magnetic resonance imaging
European Journal of Endocrinology, 2001Co-Authors: Anne E Nelson, Bruce G Robinson, Rebecca S Mason, Jeremy J Hogan, Kenneth B Jonsson, Tobias E Larsson, Erin A Martin, Hakan Ahlstrom, Gunnar Astrom, Lars WibellAbstract:A previously healthy man with no family history of fractures presented with muscle pain, back pain and height loss. Investigations revealed hypophosphataemia, phosphaturia, undetectable serum 1,25-dihydroxyvitamin D and severe Osteomalacia on bone biopsy, suggestive of a diagnosis of Oncogenic Osteomalacia. Thorough physical examination did not locate a tumour. Support for the diagnosis was obtained by detection of phosphate uptake inhibitory activity in a blinded sample of the patient's serum using a renal cell bioassay. On the basis of detection of this bioactivity, a total body magnetic resonance (MR) examination was performed. A small tumour was located in the right leg. Removal of the tumour resulted in the rapid reversal of symptoms and the abnormal biochemistry typical of Oncogenic Osteomalacia. Inhibitory activity was also demonstrated using the bioassay in serum from two other patients with confirmed or presumptive Oncogenic Osteomalacia, but not in serum from two patients with hypophosphataemia of other origin. This is the first case to be reported in which the diagnosis of Oncogenic Osteomalacia was assisted by demonstration of inhibitory activity of the patient's serum in a renal cell phosphate bioassay that provided an impetus for total body MR imaging.
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tumor expression studies indicate that hem 1 is unlikely to be the active factor in Oncogenic Osteomalacia
Bone, 1998Co-Authors: Anne E Nelson, Bruce G Robinson, Rebecca S Mason, Jeremy J Hogan, Terrence H DiamondAbstract:Abstract HEM-1 was isolated as a putative factor responsible for Oncogenic Osteomalacia by Kumar et al. (Proc Assoc Am Phys 107:296–305; 1995). The cDNA was identified on the basis of PTH-like immunoreactivity; however, no studies have been reported of the expression of HEM-1 mRNA in Oncogenic Osteomalacia tumors. In this study, expression of HEM-1 mRNA was investigated in two Oncogenic Osteomalacia tumors and in a series of normal tissues. An HEM-1 PCR product was amplified from a cDNA library from one of the tumors, with six base changes identified, as compared with the published sequence. No expression was detected, however, in the Oncogenic Osteomalacia tumors either by Northern blot analysis or by reverse transcriptase PCR. This indicates that, although a region of HEM-1 sequence is present in the tumor cell cDNA library, any HEM-1 expression must be at very low levels. It is unlikely, therefore, that the HEM-1 product is the active factor responsible for Oncogenic Osteomalacia. In the normal tissues examined, human placenta, fibroblasts, parathyroid gland, liver, fetal bone, and rat kidney cortex, HEM-1 mRNA was not detected, suggesting that it does not have a physiological role in these tissues.
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Oncogenic Osteomalacia is there a new phosphate regulating hormone
Clinical Endocrinology, 1997Co-Authors: Anne E Nelson, Bruce G Robinson, Rebecca S MasonAbstract:Oncogenic Osteomalacia is a syndrome associated with rare, usually mesenchymal tumours, which is characterized by hypophosphataemia, phosphaturia and low concentrations of 1,25-dihydroxyvitamin D. The reversal of clinical and biochemical abnormalities following removal of the tumour, indicates it is the source of a humoral factor that is responsible for these abnormalities. It has been demonstrated that the humoral factor inhibits renal phosphate uptake and reduces 1,25-dihydroxyvitamin D production. Although there is evidence that it may act via parathyroid hormone/parathyroid hormone-related peptide receptors and may be a peptide, the factor has not yet been identified, nor has its relationship to factors involved in X-linked hypophosphataemic rickets been established. We propose unifying hypotheses for the pathogenesis of Oncogenic Osteomalacia and X-linked hypophosphataemic rickets which involve defects in the PEX gene. These hypotheses do not fully explain all the available data and it remains possible that hormone(s) with little or no role in X-linked hypophosphataemic rickets may be responsible for Oncogenic Osteomalacia.
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characteristics of tumor cell bioactivity in Oncogenic Osteomalacia
Molecular and Cellular Endocrinology, 1996Co-Authors: Anne E Nelson, Heeja J Namkung, J Patava, Margaret Wilkinson, Andy C M Chang, Roger R Reddel, Bruce G Robinson, Rebecca S MasonAbstract:Abstract Oncogenic Osteomalacia is a condition where renal phosphate wasting occurs causing defective mineralisation, in the presence of a tumor. Cultures of cells were established from a hemangiopericytoma resected from a patient with Oncogenic Osteomalacia. Conditioned media from the cells inhibited phosphate uptake in opossum kidney cells and stimulated production of cAMP in rat osteosarcoma cells, a standard parathyroid hormone (PTH)-like assay. This cAMP stimulation was suppressed by the PTH analogue, 3–34 bPTH and also by heat and trypsin treatment of the media. Tests of conditioned media for PTH and parathyroid hormone related protein (PTHrP) immunoreactivity were negative, however, and no hybridisation to probes for PTH, PTHrP or human stanniocalcin was detected in tumor cell RNA on Northern blot. These data support the hypothesis that tumors responsible for Oncogenic Osteomalacia produce a humoral substance that reduces renal phosphate reabsorption and provide evidence that the factor may act via PTH/PTHrP receptors.
Ba D Nguyen - One of the best experts on this subject based on the ideXlab platform.
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coexisting hyperparathyroidism and Oncogenic Osteomalacia sestamibi and somatostatin receptor scintigraphy
Clinical Nuclear Medicine, 2006Co-Authors: Ba D NguyenAbstract:Abstract: Oncogenic Osteomalacia is a rare paraneoplastic syndrome characterized by hypophosphatemia, hyperphosphaturia, elevated alkaline phosphatase, normal calcemia, and decreased 1,25 dihydroxy vitamin D. Even with blatant metabolic imbalance and debilitating musculoskeletal symptomatology, the causative neoplasm is difficult to detect. Thus, Oncogenic Osteomalacia remains chronic until a definitive cure from tumor localization and resection. Long-term supply of phosphate and vitamin D may induce tertiary hyperparathyroidism to Oncogenic Osteomalacia making the whole clinical picture more confusing. The author presents such a case with parathyroid hyperplasia and phosphaturic mesenchymal tumor demonstrated by technetium-99m sestamibi and indium-111 octreotide.
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indium 111 pentetreotide scintigraphy of mesenchymal tumor with Oncogenic Osteomalacia
Clinical Nuclear Medicine, 1999Co-Authors: Ba D Nguyen, E A WangAbstract:The authors describe a case of Oncogenic Osteomalacia from recurrent mesenchymal tumor of the lower extremity that was demonstrated by indium-111 pentetreotide scintigraphy and MR examination. The characteristics of this rare soft-tissue neoplasm and the role of imaging diagnosis and potential thera
L Sinigaglia - One of the best experts on this subject based on the ideXlab platform.
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slow and steady wins the race the importance of perseverance in the management of Oncogenic Osteomalacia
Endocrine, 2017Co-Authors: M Manara, L SinigagliaAbstract:Despite the recent advances in understanding the pathogenesis of Oncogenic Osteomalacia, a rare paraneoplastic syndrome related to an excessive production of the phosphaturic hormone fibroblast growth factor 23 (FGF-23) by the tumor, the clinical diagnosis of this entity is still to be considered a clinical challenge, with an usual delay in the identification and treatment of affected patients that may lead to severe consequences for the individual’s quality of life. In this issue, Mathilde M. Bruins Slot-Steenks and colleagues report on a typical case of Oncogenic Osteomalacia in which a long delay from symptoms onset to correct clinical diagnosis had occurred, as well as a long time before tumor was identified and therefore an effective treatment could be established [1]. From a clinical point of view, it could be hard to suspect an Osteomalacia in the initial phases of the disease, since most patients report only nonspecific symptoms such as weakness or diffuse pain, that could be identified as related to muscle or joint involvement, thus mimicking other common clinical conditions. The occurrence of fractures could highly help in the diagnosis, but a low bone mineral density at presentation may be lacking in some patients [2]. Laboratory findings suggestive of Oncogenic Osteomalacia are hypophosphatemia associated with renal wasting of phosphate, and inappropriate normal or low levels of 1,25OH vitamin D despite normal or mildly elevated parathyroid hormone values. These features are directly related to the effect of FGF-23, which inhibits on one hand tubular phosphate reabsorption, and on the other 1α-hydroxylase activity [3]. However, serum phosphate is frequently not included in routine blood chemistry testing, and hypophosphatemia, when detected, is frequently not regarded as relevant in the clinical judgment. Moreover, renal phosphate wasting is not always evident and it can be often revealed only after a specific evaluation, as in the case reported in this issue. Furthermore, 1,25OH vitamin D level is not routinely assessed and usually it is looked for only when a specific diagnostic hypothesis has been formulated. The dosage of circulating FGF-23 has been performed in some cases as a further help in the diagnosis of Oncogenic Osteomalacia. This assay however is currently not easily available in everyday clinical practice. Moreover, other phosphatonines have recently been postulated to be implicated in the pathogenesis of phosphaturic Osteomalacia related to the tumor, such as fibroblast growth factor 7 [4]. Once the disease has been suspected based on clinical and laboratory findings, and after having ruled out other possible genetically determined renal phosphate-wasting syndromes due to FGF-23 excess, tumor detection is essential to confirm the diagnosis. Tumors responsible for Oncogenic Osteomalacia are often small, difficult to locate and slowly growing (strange tumors in strange places). Nowadays most Osteomalacia-associated tumors are classified under a single histopathologic entity and referred as phosphaturic mesenchymal tumor-mixed connective tissue variant. Due to the high expression of receptors for somatostatin in most of these neoplasms, imaging techniques involving these receptors have been utilized for tumor localization. Whole-body scintigraphy with a radiolabelled somatostatin analogous (Tc-99 octreotide or In-111 pentetreotide) was the first choice in the past, but it provides only * Luigi Sinigaglia luigi.sinigaglia@gpini.it
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a case of Oncogenic Osteomalacia detected by 111in pentetreotide total body scan
Clinical and Experimental Rheumatology, 2003Co-Authors: Silvia Casari, V Rossi, M Varenna, M Gasparini, Antonina Parafioriti, S Failoni, L SinigagliaAbstract:A case of tumor-induced Osteomalacia in a 35-year-old woman suffering from severe bone pain and muscle weakness is described. This uncommon disease is characterized by a reduced serum phosphorus level with elevated urinary phosphate excretion, normocalcemia, high serum bone alkaline phosphatase and a deficiency of 1,25 dihydroxyvitamin D 3 . The tumors responsible for Oncogenic Osteomalacia are usually small, benign and commonly located in bone or soft tissues of the head and the limbs, so the diagnosis can often be difficult. In this case a 1 1 1 In-pentetreotide scintigraphy was able to detect a hemangiopericytoma located in the right mascellar sinus. Removal of the tumor resulted in the reversal of clinical and biochemical abnormalities.
