25 resultados para NEOPLASM

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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OBJECTIVES: The phosphatidylinositol 3-kinase/AKT axis is an important cell-signaling pathway that mediates cell proliferation and survival, two biological processes that regulate malignant cell growth. The phosphatidylinositol 3-kinase CA gene encodes the p110 alpha subunit of the phosphatidylinositol 3-kinase protein. There are phosphatidylinositol 3-kinase CA mutations in several types of human tumors, and they are frequently observed in breast cancer. However, these mutations have not been investigated in Brazilian breast cancer patients. METHODS: PCR-SSCP and direct DNA sequencing were performed to identify phosphatidylinositol 3-kinaseCA exon 9 and exon 20 mutations in 86 patients with sporadic breast cancer. The relationships between PIK3CA mutations and patient clinicopathological characteristics and survival were analyzed. The presence of the TP53 mutation was also examined. RESULTS: Twenty-three (27%) of the 86 primary breast tumors contained PIK3CA mutations. In exons 9 and 20, we identified the hotspot mutations E542K, E545K, and H1047R, and we identified two new missense mutations (I1022V and L1028S) and one nonsense (R992X) mutation. Phosphatidylinositol 3-kinase CA exon 20 mutations were associated with poor overall survival and TP53 gene mutations. CONCLUSIONS: Phosphatidylinositol 3-kinase CA mutations are common in tumors in Brazilian breast cancer patients, and phosphatidylinositol 3-kinase CA and TP53 mutations are not mutually exclusive. Phosphatidylinositol 3-kinase CA exon 20 mutations are associated with poor survival, and they may be useful biomarkers for identifying breast cancer patients with aggressive tumors and for predicting the response to treatment with PI3K pathway inhibitors.

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OBJETIVO: Discutir o diagnóstico diferencial das encefalites além daquelas de etiologia infecciosa, e alertar os pediatras para a possibilidade do diagnóstico de encefalite anti-receptor N-metil-D-aspartato (rNMDA) na população pediátrica, destacando suas principais características clínicas. DESCRIÇÃO: Três pacientes apresentaram-se com uma síndrome neuropsiquiátrica inicial seguida de encefalopatia e transtornos de movimento. As características neuropsiquiátricas iniciais se desenvolveram ao longo de dias ou semanas, com mudanças comportamentais, ansiedade, confusão mental e regressão da fala. Em seguida, os pacientes evoluíram com distúrbios de movimento, caracterizados por coreoatetose ou distonia, acometendo a região orofacial e os membros. Após a exclusão das principais causas de encefalite, foram identificados anticorpos anti-rNMDA no soro e no líquido cefalorraquidiano. Não foram detectadas neoplasias durante a investigação etiológica. Os pacientes foram submetidos a imunossupressão, e dois deles tiveram uma recuperação neurológica completa. Um deles ainda apresenta uma postura distônica leve em um dos membros. COMENTÁRIOS: Os sinais clínicos de encefalite anti-rNMDA em crianças são semelhantes aos anteriormente descritos em adultos. Tumores geralmente não são detectados nessa idade. O diagnóstico de encefalite anti-rNMDA deve ser abordado após a exclusão de outras causas de encefalite na infância, como as de origem infecciosa. Pediatras devem estar atentos a essa condição autoimune passível de tratamento.

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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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The central granular cell odontogenic tumor (CGCOT) is a rare benign odontogenic neoplasm composed of varying amounts of large eosinophilic granular cells and apparently inactive odontogenic epithelium. It tends to occur as a small asymptomatic swelling in the posterior region of the mandible with nonaggressive appearance. We report an unusual case of CGCOT in the maxillary region with clinical features of malignancy. The patient underwent surgical treatment, and the 2-year follow-up revealed no signs of recurrence. Central granular cell odontogenic tumor is a very rare condition with few cases reported, especially in the maxillary region. This case highlights the possibility of aggressive behavior by these lesions.

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The DOK1 gene is a putative tumour suppressor gene located on the human chromosome 2p13 which is frequently rearranged in leukaemia and other human tumours. We previously reported that the DOK1 gene can be mutated and its expression down-regulated in human malignancies. However, the mechanism underlying DOK1 silencing remains largely unknown. We show here that unscheduled silencing of DOK1 expression through aberrant hypermethylation is a frequent event in a variety of human malignancies. DOK1 was found to be silenced in nine head and neck cancer (HNC) cell lines studied and DOK1 CpG hypermethylation correlated with loss of gene expression in these cells. DOK1 expression could be restored via demethylating treatment using 5-aza-2'deoxycytidine. In addition, transduction of cancer cell lines with DOK1 impaired their proliferation, consistent with the critical role of epigenetic silencing of DOK1 in the development and maintenance of malignant cells. We further observed that DOK1 hypermethylation occurs frequently in a variety of primary human neoplasm including solid tumours (93% in HNC, 81% in lung cancer) and haematopoietic malignancy (64% in Burkitt's lymphoma). Control blood samples and exfoliated mouth epithelial cells from healthy individuals showed a low level of DOK1 methylation, suggesting that DOK1 hypermethylation is a tumour specific event. Finally, an inverse correlation was observed between the level of DOK1 gene methylation and its expression in tumour and adjacent non tumour tissues. Thus, hypermethylation of DOK1 is a potentially critical event in human carcinogenesis, and may be a potential cancer biomarker and an attractive target for epigenetic-based therapy.

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Background: In the feline species, 80% to 93% of neoplasias in the mammary gland are malignant, being the majority carcinomas. Among them, there is the mammary squamous cell carcinoma, which amounts to a very rare neoplasm in the domestic cat, with considerable potential for malignancy. This study aimed to report a case of squamous cell mammary carcinoma in the feline species. Case: A female cat, mixed breed, ten years old, presented history of skin lesion. The cat had been spayed two years before, but with previous administration of contraceptives. At the physical examination, it was observed ulcer between the caudal abdominal mammary glands. The occurrence of skin or mammary neoplasia was conceived. The following complementary tests were requested: complete blood count, serum biochemical profile (renal and hepatic), chest radiographs, abdominal ultrasound, and incisional biopsy of the ulcerated region periphery, followed by classic histopathology. The lesion histopathology was compatible with squamous cell carcinoma of the mammary gland. Due to such a diagnosis, bilateral mastectomy was recommended. The material obtained during the surgical procedure was sent for anatomopathological analysis. Microscopically, surgical margins infiltration and a regional lymph node were verified. The owner was advised of the need for complementary therapies and medical monitoring of the cat. However, there was no return. It is noteworthy that the animal's physical and laboratory examinations showed no neoplasia in other regions, being the squamous cell carcinoma of the mammary gland considered primary. Discussion: The malignant mammary neoplasia genesis in feline species, in general, seems to be related to steroid hormones. The ovariectomized females are less likely to develop the disease when compared to intact cats, but there is no protective effect of surgery on those spayed after two years of age regarding the appearance of the neoplasia. Thus, at the time the reported patient was ovariectomized, this effect no longer occurred. The synthetic progestins regularly used to prevent estrus increase by three times the risk of breast carcinomas onset. In humans, there is no clear definition of the etiology and pathogenesis of mammary squamous cell carcinoma. However, it has been suggested its association with extreme forms of squamous metaplasia present in pre-existing mammary adenocarcinoma, besides cysts, chronic inflammations, abscesses and mammary gland adenofibromas. In a hypothetical way, this etiology could also be related to the feline mammary carcinoma, although, for the case at issue, the exogenous and endogenous hormonal influence should not be excluded. It has been reported that mammary squamous cell carcinomas in cats are classified in grades II and III (ie, moderately and poorly differentiated, respectively). Thus, they are considered tumors with more unfavorable prognosis. However, the monitoring of the clinical course, in order to evaluate possible recurrence of the neoplasia and metastases to distant sites, was not possible as the animal under discussion did not return. The squamous cell carcinoma is the most common skin tumor in feline species, despite the primary location in the mammary gland. It is, therefore, important to differentiate squamous cell carcinoma originated in the breast from histological types derived from skin. The description of this special and rare feline mammary carcinoma is important due to its particular characteristics and potential for malignancy.

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Carcinosarcoma is a rare malignant disease with aggressive behaviour rarely producing oral manifestations. This article reports a case of an intraoral carcinosarcoma affecting a 71-year-old black male; the diagnosis was made by histopathological and immunohistochemical analyses. Computed tomography scanning showed metastatic masses in the lungs. The patient was underwent a chemotherapy protocol regimen, but died as a consequence of the disease within 10 months of diagnosis. Distinctive characteristics of this presentation were the location of the lesion (floor of the mouth) and its clinical features resembling a benign lesion. A brief review of intraoral carcinosarcoma cases in the literature is also presented.

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Brachytherapy is an adequate option as monotherapy for localised prostate cancer. The objective of this study was to evaluate and compare biochemical failure free survival (BFFS) after low-dose-rate brachytherapy (LDRB) alone for patients with prostate cancer using ASTRO and Phoenix criteria, and detect prognostic factors. Data on 220 patients treated between 1998 and 2002 with LDRB were retrospectively analysed. Neoadjuvant hormone therapy was used in 74 (33.6%) patients. Median follow-up was 53.5 months (24-116). Five year BFFS was 83.0% and 83.7% using, respectively, the ASTRO and Phoenix criteria. Low -and intermediate-risk patients presented, respectively, 86.7% and 77.8% 5-year BFFS using the ASTRO definition (p=0.069), and 88.5% and 78.6% considering the Phoenix criteria (p=0.016). Bounce was observed in 66 (30%) patients. Multivariate analysis detected PSA at diagnosis < 10 ng/ml and less than 50% positive biopsy fragments as favourable prognostic factors, regarding BF using both criteria. For the Phoenix criteria, also Gleason score < 7 and low-risk group were identified as independent favourable prognostic factors. LDRB alone should be considered mostly for low-risk patients. PSA level was a strong independent prognostic factor. We support the use of the Phoenix criteria for detection of BF in patients submitted to LDRB alone.

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Objective. The objective of this preliminary study was to evaluate the expression of matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs) and growth factors in keratocystic odontogenic tumors (KOTs). Study Design. The expression of MMPs, TIMPs, growth factors, and the extracellular signal-regulated kinase (ERK) 1/2 signaling pathway were assessed by immunohistochemistry in 15 cases of KOT and 4 cases of calcifying cystic odontogenic tumor (CCOT). Results. KOT samples expressed significantly higher amounts of MMPs, TIMPs, growth factors, epidermal growth factor receptor (EGFR), and ERK compared with CCOT samples, with the exception of MMP-2 and TIMP-1. Conclusions. MMP-9, TIMP-2, EGF and transforming growth factor alpha act together and likely regulate the proliferation and aggressiveness of KOT. ERK-1/2 serves as the transducer of signals generated by these proteins, which signal through the common receptor, EGFR. This process may be related to the increased proliferation and aggressiveness observed in KOT. (Oral Surg Oral Med Oral Pathol Oral Radiol 2012;114:487-496)

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Background: Giant cell tumors of bone (GCTs) are common in the long bones, but rare in the craniofacial region, with only 1% of cases occurring in the latter. Clinical, radiological, and anatomical diagnosis of this locally aggressive disease, which occurs in response to trauma or neoplastic transformation, poses a major challenge in clinical practice. Methods: The present study describes a series of 4 cases and highlights the main features of the differential diagnosis and treatment of these lesions: GCT, giant cell reparative granuloma (GCRG), and the brown tumor of hyperparathyroidism. Results: GCT presents as a benign neoplasm, most typically affecting the knees, and rarely in the temporal and sphenoid bones. It is radiologically indistinguishable from GCRG due to its lytic, poorly defined appearance. The distinction can only be made microscopically, as the presence of multinucleated giant cells scattered throughout the stroma and the absence of a history of trauma favor a diagnosis of GCT. The brown tumor of hyperparathyroidism occurs with rapid, localized osteoclast activity secondary to the effects of increased parathyroid hormone (PTH) levels; parathyroid examination is indispensable. Conclusion: The diagnosis and treatment of these lesions poses a major challenge due to their similar clinical presentation and radiological appearance. Accurate diagnosis is essential for definition of appropriate management, as complete resection is the goal in GCT and GCRG to avoid recurrence, whereas the brown tumor often yields to treatment of the underlying hyperparathyroidism.

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Trichoepithelioma is a benign neoplasm that shares both clinical and histological features with basal cell carcinoma. It is important to distinguish these neoplasms because they require different clinical behavior and therapeutic planning. Many studies have addressed the use of immunohistochemistry to improve the differential diagnosis of these tumors. These studies present conflicting results when addressing the same markers, probably owing to the small number of basaloid tumors that comprised their studies, which generally did not exceed 50 cases. We built a tissue microarray with 162 trichoepithelioma and 328 basal cell carcinoma biopsies and tested a panel of immune markers composed of CD34, CD10, epithelial membrane antigen, Bcl-2, cytokeratins 15 and 20 and D2-40. The results were analyzed using multiple linear and logistic regression models. This analysis revealed a model that could differentiate trichoepithelioma from basal cell carcinoma in 36% of the cases. The panel of immunohistochemical markers required to differentiate between these tumors was composed of CD10, cytokeratin 15, cytokeratin 20 and D2-40. The results obtained in this work were generated from a large number of biopsies and resulted in the confirmation of overlapping epithelial and stromal immunohistochemical profiles from these basaloid tumors. The results also corroborate the point of view that trichoepithelioma and basal cell carcinoma tumors represent two different points in the differentiation of a single cell type. Despite the use of panels of immune markers, histopathological criteria associated with clinical data certainly remain the best guideline for the differential diagnosis of trichoepithelioma and basal cell carcinoma. Modern Pathology (2012) 25, 1345-1353; doi: 10.1038/modpathol.2012.96; published online 8 June 2012

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OBJETIVO: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA, punção aspirativa por agulha guiada por ultrassom endobrônquico) é um método novo em diagnóstico e estadiamento linfonodal mediastinal. O objetivo do estudo foi avaliar os resultados preliminares obtidos com EBUS-TBNA no diagnóstico de lesões e no estadiamento linfonodal mediastinal. MÉTODOS: Foram avaliados pacientes com tumores ou adenopatias mediastinais e com diagnóstico ou suspeita de câncer de pulmão. Os procedimentos foram realizados com os pacientes sob sedação ou anestesia geral. O material coletado foi preparado em lâminas fixadas em álcool absoluto para citologia e em formol para bloco de células. RESULTADOS: Foram incluídos 50 pacientes (30 do sexo masculino), com média de idade de 58,3 ± 13,5 anos. Foram realizadas 201 punções em 81 linfonodos ou massas mediastinais (média de 2,5 punções). O material obtido foi considerado adequado para análise citológica em 37 pacientes (74%), dos quais 21 (57%) foram diagnosticados com malignidade. Nos 16 pacientes remanescentes, 1 teve diagnóstico de tuberculose, 6 tiveram seguimento clínico, e 9 foram submetidos a investigação adicional (2 diagnosticados com neoplasia - resultados falso-negativos). O rendimento do exame foi maior nos procedimentos com objetivo diagnóstico, em pacientes com lesões em múltiplas estações, e nas punções da estação linfonodal subcarinal. Um paciente apresentou sangramento endobrônquico resolvido com medidas locais. Não houve mortalidade na série. CONCLUSÕES: Esta experiência preliminar confirmou que o EBUS-TBNA é procedimento seguro, e que o nosso rendimento diagnóstico, inferior ao da literatura, foi compatível com a curva de aprendizado do método.

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Dentigerous cyst (DC) is one of the most common odontogenic cysts of the jaws and rarely recurs. On the other hand, keratocystic odontogenic tumor (KCOT), formerly known as odontogenic keratocyst (OKC), is considered a benign unicystic or multicystic intraosseous neoplasm and one of the most aggressive odontogenic lesions presenting relatively high recurrence rate and a tendency to invade adjacent tissue. Two cases of these odontogenic lesions occurring in children are presented. They were very similar in clinical and radiographic characteristics, and both were treated by marsupialization. The treatment was chosen in order to preserve the associated permanent teeth with complementary orthodontic treatment to direct eruption of the associated permanent teeth. At 7-years of follow-up, none of the cases showed recurrence.

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An 84-year-old woman underwent hysterectomy due to a friable endometrial mass infiltrating almost half way through the myometrial wall. The tumor consisted of papillary structures with thin fibrovascular cores covered by several layers of pleomorphic cells. The deeply located neoplastic cells were ovoid with a pale eosinophilic cytoplasm resembling urothelial cells. A diagnosis of papillary squamous cell carcinoma of the endometrium with transitional cell differentiation was made. Although she recovered well after surgery, she died one year later because of disseminated disease. In an attempt to obtain new insights into the physiopathology of this very rare tumor, an immunohistochemical panel with 32 markers was performed. The neoplastic cells were positive for cytokeratin 5, vimentin, p63, p21, VEGF, Ki67, BAG1, and bcl-2. The expression of BAG-1 and bcl-2 may suggest that anti-apoptotic stimuli are preponderant in this neoplasm.

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Abstract Background Oral squamous cell carcinoma (OSCC) is a frequent neoplasm, which is usually aggressive and has unpredictable biological behavior and unfavorable prognosis. The comprehension of the molecular basis of this variability should lead to the development of targeted therapies as well as to improvements in specificity and sensitivity of diagnosis. Results Samples of primary OSCCs and their corresponding surgical margins were obtained from male patients during surgery and their gene expression profiles were screened using whole-genome microarray technology. Hierarchical clustering and Principal Components Analysis were used for data visualization and One-way Analysis of Variance was used to identify differentially expressed genes. Samples clustered mostly according to disease subsite, suggesting molecular heterogeneity within tumor stages. In order to corroborate our results, two publicly available datasets of microarray experiments were assessed. We found significant molecular differences between OSCC anatomic subsites concerning groups of genes presently or potentially important for drug development, including mRNA processing, cytoskeleton organization and biogenesis, metabolic process, cell cycle and apoptosis. Conclusion Our results corroborate literature data on molecular heterogeneity of OSCCs. Differences between disease subsites and among samples belonging to the same TNM class highlight the importance of gene expression-based classification and challenge the development of targeted therapies.