994 resultados para Benign bone tumor


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Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

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Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

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Ameloblastoma is a relatively uncommon benign odontogenic tumor, which is locally aggressive and has a high tendency to recur, despite its benign histopathologic features. This pathology can be classified into 4 groups: unicystic, solid or multicystic, peripheral, and malignant. There are 3 variants of unicystic ameloblastoma, as luminal, intraluminal, and mural. Therefore, in mural ameloblastoma, the fibrous wall of the cyst is infiltrated with tumor nodules, and for this reason it is considered the most aggressive variant of unicystic ameloblastomas. Various treatment techniques for ameloblastomas have been proposed, which include decompression, enucleation/curettage, sclerotizing solution, cryosurgery, marginal resection, and aggressive resection. Literature shows treatment of this lesion continues to be a subject of intense interest and some controversy. Thus, the authors aimed to describe a case of a mural unicystic ameloblastoma of follicular subtype in a 19-year-old subject who was successfully treated using conservative approaches, as decompression. The patient has been followed up for 3 years, and has remained clinically and radiographically disease-free.

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Meningiomas are the most common benign neoplasm of the brain whereas ectopic presentation, although reported, is rare. Among these ectopic tumors, there are a group of purely intraosseous meningiomas, which usually are diagnosed differentially from common primary osseous tumor such as fibrous dysplasia and osteoid osteoma. We report a 62-year-old female with a history of headaches and 6 months of progressive right parietal bulging, with no neurological signs. Parietal craniotomy was performed with immediate titanium cranioplasty of the parietal convexity. Histopathology exams revealed an ectopic intradiploic meningioma without invasion of cortical layers, with positive staining for progesterone receptors and epithelial membrane antigen. Ectopic intraosseous meningiomas remain a rare neoplasm with only a few cases reported. The main theories to justify the unusual topography appear to be embryological remains of neuroectodermal tissue or cellular dedifferentiation. Surgical treatment seems the best curative option.

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Osteosarcoma (OS) is the most common primary malignant bone tumor, usually developing in children and adolescents, and is highly invasive and metastatic, potentially developing chemoresistance. Thus, novel effective treatment regimens are urgently needed. This study was the first to investigate the anticancer effects of dehydroxymethylepoxyquinomicin (DHMEQ), a highly specific nuclear factor-kappa B (NF-kappa B) inhibitor, on the OS cell lines HOS and MG-63. We demonstrate that NF-kappa B blockade by DHMEQ inhibits proliferation, decreases the mitotic index, and triggers apoptosis of OS cells. We examined the effects of combination treatment with DHMEQ and cisplatin, doxorubicin, or methotrexate, drugs commonly used in OS treatment. Using the median effect method of Chou and Talalay, we evaluated the combination indices for simultaneous and sequential treatment schedules. In all cases, combination with a chemotherapeutic drug produced a synergistic effect, even at low single-agent cytotoxic levels. When cells were treated with DHMEQ and cisplatin, a more synergistic effect was obtained using simultaneous treatment. For the doxorubicin and methotrexate combination, a more synergistic effect was achieved with sequential treatment using DHMEQ before chemotherapy. These synergistic effects were accompanied by enhancement of chemoinduced apoptosis. Interestingly, the highest apoptotic effect was reached with sequential exposure in both cell lines, independent of the chemotherapeutic agent used. Likewise, DHMEQ decreased cell invasion and migration, crucial steps for tumor progression. Our data suggest that combining DHMEQ with chemotherapeutic drugs might be useful for planning new therapeutic strategies for OS treatment, mainly in resistant and metastatic cases. Anti-Cancer Drugs 23:638-650 (C) 2012 Wolters Kluwer Health broken vertical bar Lippincott Williams & Wilkins.

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Juvenile nasopharyngeal angiofibroma is a rare benign vascular tumor of the nasopharynx. Although the treatment of choice is surgery, there is no consensus on what is the best approach. Aim: To compare surgical time and intraoperative transfusion requirements in patients undergoing endoscopic surgery versus open / combined and relate the need for transfusion during surgery with the time between embolization and surgery. Material and Methods: Study descriptive, analytical, retrospective study with a quantitative approach developed in the Otorhinolaryngology department of a teaching hospital. Analyzed 37 patients with angiofibroma undergoing surgical treatment. Data obtained from medical records. Analyzed with tests of the Fisher-Freeman-Halton and Games-Howell. Was considered significant if p <0.05. Study design: Historical cohort study with cross-sectional. Results: The endoscopic approach had a shorter operative time (p <0.0001). There is less need for transfusion during surgery when the embolization was performed on the fourth day. Conclusion: This suggests that the period ahead would be ideal to perform the process of embolization and endoscopic surgery by demanding less time would be associated with a lower morbidity. This study, however, failed to show which group of patients according to tumor stage would benefit from specific technical.

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Infantile digital fibromatosis or Reye's tumor is a benign fibroproliferative tumor, the etiopathogenesis of which has yet to be fully clarified. It typically presents at birth or in the first year of life and is characterized by a firm, flesh colored or erythematous nodule or nodules located on the digits. These lesions tend to regress spontaneously.

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Brunner’s gland hamartoma (BGH) is an extremely rare benign digestive tumor, generally located in the duodenal bulb. We report the case of a 51-year-old asymptomatic man with a large pedunculated BGH arising from the pylorus. It was successfully removed en bloc by endoscopic resection.

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Il sarcoma di Ewing (ES) è un tumore maligno pediatrico dell’apparato scheletrico; è associato a una traslocazione specifica codificante la proteina di fusione EWS-FLI1 e all’alta espressione di CD99, una glicoproteina di membrana fisiologicamente coinvolta in diversi processi biologici. EWS-FLI1 e CD99, sono riportati avere ruoli divergenti nella modulazione della malignità e del differenziamento di ES. CD99 inoltre è riportato modulare il pathway di MAPK, il quale interagendo con molteplici fattori di trascrizione partecipa a processi di proliferazione e differenziamento. In questo studio abbiamo investigato in due linee cellulari di ES silenziate per CD99 (TC-71shCD99 e IOR/CARshCD99) l’attività basale di diversi fattori trascrizionali quali: NF-kBp65, AP1, Elk-1, E2F e CREB. L’unico fattore trascrizionale statisticamente significativo è risultato essere NF-kBp65 e abbiamo valutato il suo ruolo nel differenziamento neurale di cellule di ES e la relazione con EWS-FLI1 e CD99. L’attività trascrizionale di NF-kB è stata valutata attraverso gene reporter assay in linee cellulari di ES a diversa espressione di CD99, EWS-FLI1 e NF-kB stesso. Il differenziamento neurale è stato valutato come espressione di βIII-Tubulin in immunofluorescenza. Il silenziamento di CD99 induce una down-modulazione dell’attività trascrizionale di NF-kB, mentre il knockdown di EWS-FLI1 ne induce un’aumento. Inoltre, il silenziamento di EWS-FLI1 non è in grado di contrastare la riduzione dell’attività di NF-kB osservata dopo silenziamento di CD99, suggerendo un ruolo dominante del CD99 nel signaling di NF-kB. Cellule deprivate di CD99 ma non di EWS-FLI1, mostrano un fenotipo differenziato in senso neurale, fenotipo che viene perso quando le cellule sono indotte a sovraesprimere NF-kB. Inoltre, in cellule CD99 positive, il silenziamento di NF-kB induce un leggero differenziamento neurale. In conclusione, questi dati hanno evidenziato il ruolo di NF-kB nel differenziamento di cellule di ES e che potrebbe essere un potenziale target nel ridurre la progressione di questo tumore.

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L’osteosarcoma (OS) è il tumore primitivo dell’osso più comune in età pediatrica e adolescenziale. L’OS è stato recentemente riconsiderato come una patologia da de-differenziamento, legata all’interruzione del processo cui vanno incontro i precursori osteoblastici, quali le cellule staminali mesenchimali (MSCs), per trasformarsi in osteoblasti maturi. Il sistema IGF è coinvolto nella regolazione della proliferazione e del differenziamento di cellule di OS. IRS-1 è un mediatore critico di tale via di segnalazione e il suo livello di espressione modula il differenziamento di cellule ematopoietiche. Lo scopo di questa tesi è stato quello di definire il ruolo di IRS-1 nel differenziamento osteoblastico di MSCs e cellule di OS. Il potenziale differenziativo di cellule di OS umano e murino e di MSCs derivate da midollo osseo è stato valutato tramite Alizarin Red staining e Real Time-PCR. Dai dati ottenuti è emerso come i livelli di espressione di IRS-1 diminuiscano durante il differenziamento osteoblastico. Conseguentemente, i livelli di espressione di IRS-1 sono stati manipolati utilizzando shRNA per down-regolare l’espressione della proteina o un plasmide per sovra-esprimerla. Sia la down-regolazione sia la sovra-espressione di IRS-1 hanno inibito il differenziamento osteoblastico delle linee cellulari considerate. Allo scopo di valutare il contributo di IRS-1 nella via di segnalazione di IGF-1R è stato utilizzato l’inibitore di tale recettore, αIR-3. Anche in questo caso è stata osservata una riduzione della capacità differenziativa. L’inibitore del proteasoma MG-132 ha portato ad un aumento dei livelli di IRS-1, portando nuovamente all’inibizione del differenziamento osteoblastico e suggerendo che l’ubiquitinazione di questa proteina potrebbe avere un ruolo importante nel mantenimento di appropriati livelli di espressione di IRS-1. I risultati ottenuti indicano la criticità dei livelli di espressione di IRS-1 nella determinazione della capacità differenziativa sia di cellule di OS umano e murino, sia delle MSCs.

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CD99 is a 32 kDa transmembrane protein whose high expression characterizes Ewing sarcoma (ES), a very aggressive pediatric bone tumor. In addition to its diagnostic value, CD99 has therapeutic potential since it leads to rapid and massive ES cell death when engaged with specific antibodies. Here a novel mechanism of cell death triggered via CD99 is shown, leading, ultimately, to the appearance of macropinocytotic vescicles. Anti-CD99 mAb 0662 induces MDM2 ubiquitination and degradation, which causes not only a p53 reactivation but also the IGF-1R induction and its subsequent internalization; CD99 results internalized together with IGF-1R inside endosomes, but then the two molecules display a different sorting: CD99 is degraded, while IGF-1R is recycled on the surface, causing, as a final step, the up-regulation of RAS-MAPK. High-expressing CD99 mesenchymal stem cells show mild Ras induction but no p53 activation and escape cell death, but in presence of EWS/FLI1 mesenchymal stem cells expressing CD99 show a stronger Ras induction and a p53 reactivation, leading to a significant cell death rate. We propose that CD99 triggering in a EWS/FLI1-driven oncogenetic context creates a synergy between RAS upregulation and p53 activation in ES cells, leading to cell death. Moreover, our data rule out possible concerns on toxicity related to the broad CD99 expression in normal tissues and provide the rationale for the therapeutic use of anti-CD99 MAbs in the clinic.

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Ossifying fibromas are rare benign bone-related lesions of the jaw. Early diagnosis based on clinical, radiologic, and pathohistologic findings is essential, since undetected lesions may expand and cause considerable functional and cosmetic problems. The treatment of choice is purely surgical. Periodic clinical and radiologic follow-up should be scheduled, since recurrence is possible. The present article describes the diagnostic procedures, surgical management, and follow-up of an asymptomatic ossifying fibroma in the mandible of a 21-year-old man.

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Cystadenomas are a rare, painless, and slow-growing benign epithelial tumor of the salivary gland. This article describes the case of a papillary cystadenoma in the lower lip of a 46-year-old man. The lesion was removed using a carbon dioxide laser, and there were no signs of recurrence 1 year postoperatively.

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INTRODUCTION The influence of specific health problems on health-related quality of life (HRQoL) in childhood cancer survivors is unknown. We compared HRQoL between survivors of childhood cancer and their siblings, determined factors associated with HRQoL, and investigated the influence of chronic health problems on HRQoL. METHODS Within the Swiss Childhood Cancer Survivor Study, we sent a questionnaire to all survivors (≥16 years) registered in the Swiss Childhood Cancer Registry, who survived >5 years and were diagnosed 1976-2005 aged <16 years. Siblings received similar questionnaires. We assessed HRQoL using Short Form-36 (SF-36). Health problems from a standard questionnaire were classified into overweight, vision impairment, hearing, memory, digestive, musculoskeletal or neurological, and thyroid problems. RESULTS The sample included 1,593 survivors and 695 siblings. Survivors scored significantly lower than siblings in physical function, role limitation, general health, and the Physical Component Summary (PCS). Lower score in PCS was associated with a diagnosis of central nervous system tumor, retinoblastoma or bone tumor, having had surgery, cranio-spinal irradiation, or bone marrow transplantation. Lower score in Mental Component Summary was associated with older age. All health problems decreased HRQoL in all scales. Most affected were survivors reporting memory problems and musculoskeletal or neurological problems. Health problems had the biggest impact on physical functioning, general health, and energy and vitality. CONCLUSIONS In this study, we showed the negative impact of specific chronic health problems on survivors' HRQoL. IMPLICATIONS FOR CANCER SURVIVORS Therapeutic preventive measures, risk-targeted follow-up, and interventions might help decrease health problems and, consequently, improve survivors' quality of life.

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The Soehner-Dmochowski strain of murine sarcoma virus (MuSV-SD) was derived from a bone tumor of a New Zealand Black (NZB) rat infected with the Moloney strain of MuSV, which carries the gene encoding the v-mos protein. Serial passage of cell-free tumor extracts both decreased the latent period and resulted in osteosarcomas. Cells from a late passage tumor were established in culture, cell-free extracts frozen, and later inoculated into newborn NZB rats. One of the resulting bone tumors was established in culture and clonal cell lines derived, of which S4 was selected for the present study. The objectives of the study were two-fold: an examination of the genetic organization of MuSV-SD, and an examination of the biochemical characteristics of the viral proteins, since this is an acutely transforming virus which may yield insights into the mechanism of transformation caused by the v-mos protein. Blot hybridization of digested S4 genomic DNA reveals three candidate MuSV-SD integrated viral DNAs. The largest of these, MuSV-SD-6.5, was cloned from an S4 cosmid library, and the complete MuSV-SD-mos sequence was determined. The predicted amino acid sequence of the v-mos protein was compared to that of MuSV-124 and Ht-1, which show a 96.5% and 97.1% similarity, respectively. To characterize the MuSV-SD-mos protein further, immunochemical assays were performed using anti-mos antisera. The immunoblot analysis and immunoprecipitation assays demonstrated that similar levels of the v-mos protein were present in cells chronically infected with either MuSV-SD or MuSV-124; however, the immune complex kinase assay revealed greatly reduced in vitro serine kinase activity of the MuSV-SD-mos protein compared to that of MuSV-124. Sequence analysis demonstrated that the serine at amino acid residue 358 of the MuSV-SD-mos protein, like that of MuSV-Ht-1, had been mutated to a glycine. Mutations of this serine residue have been shown to affect the detectable in vitro kinase activity, however, v-mos proteins containing this mutation still retain transforming properties. Therefore, although the characteristic in vitro kinase activity of the MuSV-SD-mos protein has not been demonstrated, it is clear that this virus is a potent transforming agent. ^