917 resultados para clear cell carcinoma


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Background: Most of the primary pulmonary tumors in dogs are malignant and from epithelial origin, being bronchioalveolar tumors more prevalent. Adenocarcinoma of clear cells, however, is a very rare pulmonary tumor and its origin is still unknown. It is related to several clinical abnormalities, including hypertrophic osteopathy, an unusual paraneoplastic syndrome characterized by a periosteal reaction along the shaft of long bones. Because of the unusual presentation of the pulmonary adenocarcinoma, the aim of this study was to describe the radiographic, histopathological, and immunohistochemical fi ndings of a dog affl icted with hypertrophic osteopathy secondary to an undifferentiated pulmonary adenocarcinoma of clear cells. Case: A 12-year-old, 45 kg, not castrated male Great Dane dog was presented with painful swelling of all four limbs and moderate respiratory distress. Radiographic examination and computed tomography of the limbs showed palisade-like periosteal bone proliferation involving radius, ulna, femur, patella, tibia, fi bula, tarsus, metacarpal, metatarsal and digits, suggesting hypertrophic osteopathy. Radiographic examination and computed tomography of the lungs also showed a round mass well delimited localized in the right diaphragmatic lobe. A lobectomy of the right diaphragmatic lobe and partial lobectomy of accessory lobe were performed. A poorly differentiated clear squamous cell carcinoma was diagnosed by histological examination. An immune-panel of CK5/CK6, CK7, p63 and TTF-1 was used for immunophenotyping. Immunostaining was weakly positive for CK5/CK6 and negative to all others. Therefore, the diagnosis was poorly differentiated clear cell adenocarcinoma. The dog showed improvement in clinical signs seven days after surgery. One month postoperatively, radiographic examination of the limbs showed less intense periosteal reaction and initiation of bone remodeling. Discussion: Primary pulmonary tumors are considered very infrequent in small animals, but its true incidence rate is dif- fi cult to establish in animal populations. The histological origin of the tumor in the present case, as verifi ed in the literature, is not well established by histological analysis. In these situations, the immunohistochemistry panel may be useful. The modifi cation of the diagnosis between histological analysis and by immunohistochemistry, among other factors, might be due to transdifferentiation from one phenotype to another at various stages in the neoplastic process. The clear cell appearance observed in this case may be verifi ed in all types of carcinoma due to intracellular accumulation of glycogen, most of which is dissolved during the preparation of paraffi n sections. This uncommon neoplasm apparently did not infl uence the radiographic or tomographic fi ndings of the hypertrophic osteopathy in the present case. The frequency of metastases depends on the histological type of the tumor, being common in the pulmonary adenocarcinoma and usually to tracheobronchial lymph nodes and pulmonary parenchyma. Although in this case the imaging studies did not show metastases to other pulmonary lobes, the histological exams showed metastatic lesions that may be associated to the dog’s death after the surgery.

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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 profi le (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 infi ltration and a regional lymph node were verifi ed. 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 defi nition 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 infl ammations, abscesses and mammary gland adenofi bromas. 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 infl uence should not be excluded. It has been reported that mammary squamous cell carcinomas in cats are classifi ed 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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Hepatocellular carcinoma (HCC) is the second most common primary malignant hepatic tumor in children. It often develops in patients with underlying liver disease. We report the clinicopathologic features of an unusual HCC occurring in an infant who presented with features of Cushing's syndrome due to bilateral adrenal hyperplasia. The tumor is characterized by epithelial syncytial giant cells. Giant cell carcinoma of the liver has been previously reported, but the cells were osteoclast-like (ie, mesenchymal type) and not epithelial type as it is in this patient. We propose to use the term HCC, syncytial giant cell type, to denote this apparently novel lesion.

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Retinoids have been found to be effective in the prevention of premalignant lesions and second primary cancers in the upper aerodigestive tract. Further development of retinoids for prevention and therapy of head and neck squamous cell carcinoma (HNSCC) requires a better understanding of their mechanism of action on the growth and differentiation of such cells. I have chosen to employ cultured HNSCC cell lines as a model system for investigating the mechanism underlying the effects of retinoids. These cells are useful because all-trans retinoic acid (ATRA) inhibits their proliferation. Furthermore, two HNSCC cell lines were found to express three squamous differentiation (SqD) markers characteristic of normal keratinocytes and ATRA suppressed the expression of these markers as reported for normal keratinocytes. It is thought that nuclear retinoic acid receptors (RARs and RXRs), which act as DNA-binding transcription modulating factors, mediate the effects of retinoids on the growth and differentiation of normal and tumor cells. I found that all four cell lines examined expressed RAR-$\alpha ,$ RAR-$\tau ,$ and RXR-$\alpha$ and three of four expressed RAR-$\beta .$ ATRA treatment increased the level of RAR-$\alpha ,$ -$\beta ,$ and -$\tau$ in four cell lines. Two HNSCC cell lines that exhibited a progressive increase in the expression of SqD markers during growth in culture also showed a concurrent decrease in RAR-$\beta$ level. Moreover, increasing concentrations of RA suppressed the SqD marker while inducing RAR-$\beta$ mRNA. Several synthetic retinoids which exhibit a preference for binding to specific nuclear RARs showed a differential ability to inhibit cell proliferation, transactivate transcription of the reporter genes (CAT and luciferase) from the RA response element (RARE) of the RAR-$\beta$ gene, and induce RAR-$\beta$ expression. Those retinoids that were effective inducers of RAR-$\beta$ also suppressed SqD effectively, indicating an inverse relationship exists between the expression of RAR-$\beta$ and SqD. This inverse relationship suggests a role for RAR-$\beta$ in the suppression of SqD. ^

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Merkel cell carcinoma (MCC) is a rare aggressive skin tumor which shares histopathological and genetic features with small-cell lung carcinoma (SCLC), both are of neuroendocrine origin. Comparable to SCLC, MCC cell lines are classified into two different biochemical subgroups designated as 'Classic' and 'Variant'. With the aim to identify typical gene-expression signatures associated with these phenotypically different MCC cell lines subgroups and to search for differentially expressed genes between MCC and SCLC, we used cDNA arrays to pro. le 10 MCC cell lines and four SCLC cell lines. Using significance analysis of microarrays, we defined a set of 76 differentially expressed genes that allowed unequivocal identification of Classic and Variant MCC subgroups. We assume that the differential expression levels of some of these genes reflect, analogous to SCLC, the different biological and clinical properties of Classic and Variant MCC phenotypes. Therefore, they may serve as useful prognostic markers and potential targets for the development of new therapeutic interventions specific for each subgroup. Moreover, our analysis identified 17 powerful classifier genes capable of discriminating MCC from SCLC. Real-time quantitative RT-PCR analysis of these genes on 26 additional MCC and SCLC samples confirmed their diagnostic classification potential, opening opportunities for new investigations into these aggressive cancers.

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INTRODUCTION: The dichotomization of non-small cell carcinoma (NSCLC) subtype into squamous (SQCC) and adenocarcinoma (ADC) has become important in recent years and is increasingly required with regard to management. The aim of this study was to determine the utility of a panel of commercially available antibodies in refining the diagnosis on small biopsies and also to determine whether cytologic material is suitable for somatic EGFR genotyping in a prospectively analyzed series of patients undergoing investigation for suspected lung cancer. METHODS: Thirty-two consecutive cases of NSCLC were first tested using a panel comprising cytokeratin 5/6, P63, thyroid transcription factor-1, 34betaE12, and a D-PAS stain for mucin, to determine their value in refining diagnosis of NSCLC. After this test phase, two further pathologists independently reviewed the cases using a refined panel that excluded 34betaE12 because of its low specificity for SQCC, and refinement of diagnosis and concordance were assessed. Ten cases of ADC, including eight derived from cytologic samples, were sent for EGFR mutation analysis. RESULTS: There was refinement of diagnosis in 65% of cases of NSCLC to either SQCC or ADC in the test phase. This included 10 of 13 cases where cell pellets had been prepared from transbronchial needle aspirates. Validation by two further pathologists with varying expertise in lung pathology confirmed increased refinement and concordance of diagnosis. All samples were adequate for analysis, and they all showed a wild-type EGFR genotype. CONCLUSION: A panel comprising cytokeratin 5/6, P63, thyroid transcription factor-1, and a D-PAS stain for mucin increases diagnostic accuracy and agreement between pathologists when faced with refining a diagnosis of NSCLC to SQCC or ADC. These small samples, even cell pellets derived from transbronchial needle aspirates, seem to be adequate for EGFR mutation analysis.

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OBJECTIVE: Ovarian cancer is the leading cause of death from gynecologic malignancies in the Western world. Fibroblast growth factor receptor (FGFR) signaling has been implicated to play a role in ovarian tumorigenesis. Mutational activation of one member of this receptor family, FGFR2, is a frequent event in endometrioid endometrial cancer. Given the similarities in the histologic and molecular genetics of ovarian and endometrial cancers, we hypothesized that activating FGFR2 mutations may occur in a subset of endometrioid ovarian tumors, and possibly other histotypes. METHODS: Six FGFR2 exons were sequenced in 120 primary ovarian tumors representing the major histologic subtypes. RESULTS: FGFR2 mutation was detected at low frequency in endometrioid (1/46, 2.2%) and serous (1/41, 2.4%) ovarian cancer. No mutations were detected in clear cell, mucinous, or mixed histology tumors or in the ovarian cancer cell lines tested. Functional characterization of the FGFR2 mutations confirmed that the mutations detected in ovarian cancer result in receptor activation. CONCLUSIONS: Despite the low incidence of FGFR2 mutations in ovarian cancer, the two FGFR2 mutations identified in ovarian tumors (S252W, Y376C) overlap with the oncogenic mutations previously identified in endometrial tumors, suggesting activated FGFR2 may contribute to ovarian cancer pathogenesis in a small subset of ovarian tumors.

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Human papillomaviruses (HPVs) cause cervical cancer and some other types of epithelial cancers. HPV types from the phylogenic beta genus (beta-PVs), formerly known as epidermodysplasia verruciformis–associated HPV types, are frequently detected in nonmelanoma skin cancers, especially in squamous cell carcinomas (SCCs). An etiologic relationship with beta-PV infection is suspected...

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Background: Few patients diagnosed with lung cancer are still alive 5 years after diagnosis. The aim of the current study was to conduct a 10-year review of a consecutive series of patients undergoing curative-intent surgical resection at the largest tertiary referral centre to identify prognostic factors. Methods: Case records of all patients operated on for lung cancer between 1998 and 2008 were reviewed. The clinical features and outcomes of all patients with non-small cell lung cancer (NSCLC) stage I-IV were recorded. Results: A total of 654 patients underwent surgical resection with curative intent during the study period. Median overall survival for the entire cohort was 37 months. The median age at operation was 66 years, with males accounting for 62.7 %. Squamous cell type was the most common histological subtype, and lobectomies were performed in 76.5 % of surgical resections. Pneumonectomy rates decreased significantly in the latter half of the study (25 vs. 16.3 %), while sub-anatomical resection more than doubled (2 vs. 5 %) (p < 0.005). Clinico-pathological characteristics associated with improved survival by univariate analysis include younger age, female sex, smaller tumour size, smoking status, lobectomy, lower T and N status and less advanced pathological stage. Age, gender, smoking status and tumour size, as well as T and N descriptors have emerged as independent prognostic factors by multivariate analysis. Conclusion: We identified several factors that predicted outcome for NSCLC patients undergoing curative-intent surgical resection. Survival rates in our series are comparable to those reported from other thoracic surgery centres. © 2012 Royal Academy of Medicine in Ireland.