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991.
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Background

A number of osteoblastic meningiomas, primary osteosarcomas of the meninges, and post-radiation osteosarcomas of the head have been reported. However, postradiation dedifferentiation of meningioma into osteosarcoma has not been reported previously.

Case presentation

In 1987 a caucasian man, then 38 years old, presented with a pituitary macroadenoma. He underwent a subtotal resection of the tumor and did well until 1990 when a recurrent tumor was diagnosed. This was treated with subtotal resection of the tumor, followed by radiation therapy for six weeks to a total of 54 Gy. He was considered "disease-free" for nearly ten years. However, most recently in July 2000, he presented with a visual field deficit due to a second recurrence of his pituitary macroadenoma, now with suprasellar extension. At this time, as an incidental finding, a mass attached to the dura was noted in the left parietal hemisphere. This dura–based mass had grown rapidly by January 2001 and was excised. It showed histological, immunohistochemical, and electron microscopic features of malignant meningioma and osteosarcoma with a sharp demarcation between the two components.

Conclusions

We report a rare case of a radiation induced dedifferentiation of meningioma into osteosarcoma, which has not been reported previously.  相似文献   
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Most of the predisposition to hereditary breast and ovarian cancer has been attributed to inherited defects in two tumor suppressor genes BRCA1 and BRCA2. To explore the contribution of BRCA1 mutations to hereditary breast cancer among Indian women, we examined the coding sequence of the BRCA1 gene in 14 breast cancer patients with a positive family history of breast and/or ovarian cancer. Mutation analysis was carried out using conformation sensitive gel electrophoresis (CSGE) followed by sequencing. Three mutations (21%) in the BRCA1 gene were identified. Two of them are novel mutations of which one is a missense mutation in exon 7 near the RING finger domain, while the other is a one base pair deletion in exon 11 which results in protein truncation. The third mutation, 185 delAG, has been previously described in Ashkenazi Jewish families. To our knowledge this is the first report of a study of germline BRCA1 mutation analysis in familial breast cancer in India. Our data from 14 different families suggests a lower prevalence but definite involvement of germline mutations in the BRCA1 gene among Indian women with breast cancer and a family history of breast cancer.  相似文献   
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A 13-year-old female child diagnosed initially as having tuberculosis was subsequently found to have adenocarcinoma colon with secondaries in ovaries and omentum, and proved to be mucinous carcinoma on biopsy. Patient received chemotherapy (FAM) regimen without any relief even 2 months after surgery.  相似文献   
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Since a universal definition for hypoglycemia is lacking, an operational threshold for initiating therapy has been defined. Hypoglycemia is encountered in a variety of neonatal conditions including prematurity, growth retardation and maternal diabetes. Since hypoglycemia may be asymptomatic, routine screening for this condition in certain high risk situations is recommended. Supervised breast-feeding may be a treatment option in asymptomatic hypoglycemia. However, symptomatic hypoglycemia should always be treated with a continuous infusion of parenteral dextrose. Neonates needing dextrose infusion rates above 12 mg/kg/m should be investigated for refractory causes of hypoglycemia. Hypoglycemia has been linked to poor neuro-developmental outcome and hence aggressive screening and treatment is recommended.  相似文献   
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The use of hematopoietic stem cell transplantation (HSCT) in the treatment of children afflicted with many potentially fatal malignant and nonmalignant diseases is well recognized. Although outcomes continue to improve and the utility of HSCT is increasing, HSCT remains a complicated process necessitating support from many medical disciplines, including radiology. Importantly, children who undergo HSCT are at risk for the development of specific complications that are linked to the timeline of transplantation, as well as to the relationship between the underlying diagnoses, severe immune deficiency, cytoreductive regimen, and graft-versus-host reactions. An understanding of the complex interplay of the immune status, therapeutic regimen, and disease allows increased diagnostic accuracy. Successful treatment of these high-risk children requires that radiologists who are involved with their care be familiar with broad concepts, as well as with specific problems that frequently occur following HSCT. In this article, the clinical aspects of pediatric HSCT are summarized, including common complications, and imaging features of these complications are described.  相似文献   
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OBJECTIVE: The purpose of our study was to detect changes in renovascular resistance through renal Doppler indexes in young sickle cell disease patients with normal routine urine laboratory tests. CONCLUSION: Renal Doppler sonography resistive index and pulsatility index values can serve as early radiologic predictors of renovascular changes in sickle cell disease. Thereby, these findings can guide clinicians in the use of more intensive monitoring of laboratory values and initiating adequate treatment at an early stage.  相似文献   
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