RESUMO
AIMS: Renal cell carcinomas (RCCs) represent 2-5% of kidney malignancies in children and adolescents. Appropriate diagnostic and classification are crucial for the correct management of the patients and in order to avoid inappropriate pre-operative chemotherapy, which is usually recommended if a Wilms' tumour is suspected. METHODS AND RESULTS: A French-Italian series of 93 renal cell carcinomas collected from 1990 to 2019 in patients aged less than 18 years was reclassified according to the 2016 World Health Organization (WHO) classification and the latest literature. TFE3 and TFEB fluorescence in-situ hybridisation (FISH) analyses and a panel of immunohistochemical stains were applied. The median age at diagnosis was 11 years (range = 9 months-17 years). MiT family (MiTF) translocation RCCs accounted for 52% of the tumours, followed by papillary (20%) and unclassified RCCs (13%). Other subtypes, such as SDHB-deficient and fumarate hydratase-deficient RCCs, represented 1-3% of the cases. We also described a case of ALK-rearranged RCC with a metanephric adenoma-like morphology. CONCLUSION: A precise histological diagnosis is mandatory, as targeted therapy could be applied for some RCC subtypes, i.e. MiTF-translocation and ALK-translocation RCC. Moreover, some RCC subtypes may be associated with a predisposition syndrome that will impact patients' and family's management and genetic counselling. A precise RCC subtype is also mandatory for the clinical management of the patients and inclusion in new prospective clinical trials.
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Carcinoma de Células Renais , Neoplasias Renais , Tumor de Wilms , Adolescente , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Carcinoma de Células Renais/patologia , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Translocação GenéticaRESUMO
Sarcoma with EWSR1-PATZ1 gene fusion is an exceedingly rare and newly described Ewing-like sarcoma harboring EWSR1 rearrangements involving fusion partners other than ETS family genes. The clinical, histopathologic and immunophenotypic features of cases reported in literature are fairly diverse and not specific. We report a new case report posing real challenges for histological and molecular diagnosis.
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Proteínas de Fusão Oncogênica , Sarcoma de Ewing , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Fatores de Transcrição Kruppel-Like/genética , Proteínas de Fusão Oncogênica/genética , Proteína EWS de Ligação a RNA/genética , Proteínas Repressoras/genética , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/genética , Fatores de TranscriçãoRESUMO
The last international guidelines on HER2 determination in breast cancer have been updated in 2018 by the American Society of Clinical Oncology and College of American Pathologists, on the basis of a twenty-year practice and results of numerous clinical trials. Moreover, the emerging HER2-low concept for 1+ and 2+ non amplified breast cancers lead to refine French practices for HER2 status assessment. The GEFPICS group, composed of expert pathologists, herein presents the latest French recommendations for HER2 status evaluation in breast cancer, taking into account the ASCO/CAP guidelines and introducing the HER2-low concept. In the era of personalized medicine, HER2 status assessment remains one of the most important biomarkers in breast cancer and its quality guaranties the optimal patients' care. French pathologists' commitment in theranostic biomarker quality is more than ever required to provide the most efficient cares in oncology.
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Neoplasias da Mama , Biomarcadores Tumorais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Receptor ErbB-2/genéticaRESUMO
Liver transplantation (LT) has been proposed as a curative treatment in hereditary hemorrhagic telangiectasia (HHT) with severe hepatic involvement. We provide a long-term evaluation of graft status after LT for HHT, with a focus on the risk of recurrence. The present study included all patients prospectively followed up after LT for HHT in the Lyon Liver Transplant Unit from 1993 to 2010, with a survival of more than 1 year. Protocol clinical, radiological, and histological examinations were performed at regular intervals. Fourteen patients were included (13 women and one man). Median age at LT was 52.5 years (range: 33.1-66.7). In eight patients (seven female), disease recurrence was diagnosed by abnormal radiological features, suggestive of microcirculatory disturbances. Typical vascular lesions, including telangiectasia, were demonstrated by liver biopsy in five of these patients. The median interval between LT and diagnosis of recurrence was 127 months (range: 74-184). The risk of recurrence increased over time; estimated cumulative risk was 47.9% at 15 years. Liver tissue analysis found the coexistence of an angiogenic process combined with endothelial microchimerism, as shown by the presence of vascular lining cells of recipient origin. Conclusion: The present data show that disease recurrence occurs, usually after a long delay, in a significant number of patients treated by LT for liver complications of HHT. This strongly supports the necessity of a lifelong follow-up and suggests that therapeutic strategy needs discussion and evaluation, especially of the role of potential adjuvant treatments to LT, such as antiangiogenic medications, when recurrent disease appears.
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Transplante de Fígado , Complicações Pós-Operatórias/epidemiologia , Telangiectasia Hemorrágica Hereditária/cirurgia , Adulto , Idoso , Feminino , Seguimentos , França/epidemiologia , Humanos , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Recidiva , Telangiectasia Hemorrágica Hereditária/diagnóstico por imagem , Telangiectasia Hemorrágica Hereditária/epidemiologia , Transplantes/diagnóstico por imagemRESUMO
Neoadjuvant therapy is an increasing treatment option in the management of breast cancer. The tumor response to neoadjuvant therapy, especially the pathological complete response, is a validated endpoint frequently used in clinical trials. However, there is still a lack of standardization for the surgical specimen management in the neoadjuvant setting. This leads to heterogeneity in the specimen handling and might lead to significant bias for the prognostic assessment of patients or in clinical trials. The GEFPICS group, composed of expert breast cancer pathologists, herein presents guidelines for the management of breast and axillary specimen before treatment (management of biopsy, items of the pathological report) and after neoadjuvant therapy (specimen handling, histological assessment of response, items of the pathological report and response grading systems).
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Neoplasias da Mama/patologia , Mama/patologia , Linfonodos/patologia , Terapia Neoadjuvante , Manejo de Espécimes/normas , Biomarcadores Tumorais , Biópsia/métodos , Biópsia/normas , Neoplasias da Mama/química , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Quimioterapia Adjuvante/normas , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , França , Humanos , Linfonodos/efeitos dos fármacos , Linfonodos/cirurgia , Prontuários Médicos/normas , Microscopia , Neoplasia Residual/patologia , Prognóstico , Biópsia de Linfonodo Sentinela/métodos , Manejo de Espécimes/métodos , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacosRESUMO
Tetraploidy can constitute a metastable intermediate between normal diploidy and oncogenic aneuploidy. Here, we show that the absence of p53 is not only permissive for the survival but also for multipolar asymmetric divisions of tetraploid cells, which lead to the generation of aneuploid cells with a near-to-diploid chromosome content. Multipolar mitoses (which reduce the tetraploid genome to a sub-tetraploid state) are more frequent when p53 is downregulated and the product of the Mos oncogene is upregulated. Mos inhibits the coalescence of supernumerary centrosomes that allow for normal bipolar mitoses of tetraploid cells. In the absence of p53, Mos knockdown prevents multipolar mitoses and exerts genome-stabilizing effects. These results elucidate the mechanisms through which asymmetric cell division drives chromosomal instability in tetraploid cells.
Assuntos
Carcinoma/metabolismo , Neoplasias do Colo/metabolismo , Genes mos , Mitose , Poliploidia , Proteína Supressora de Tumor p53/metabolismo , Aneuploidia , Animais , Carcinoma/genética , Linhagem Celular Tumoral , Centrossomo/metabolismo , Instabilidade Cromossômica , Neoplasias do Colo/genética , Feminino , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Proteína Supressora de Tumor p53/genéticaRESUMO
Biomarker assessment of breast cancer tumor samples is part of the routine workflow of pathology laboratories. International guidelines have recently been updated, with special regards to the pre-analytical steps that are critical for the quality of immunohistochemical and in situ hybridization procedures, whatever the biomarker analyzed. Fixation and specimen handling protocols must be standardized, validated and carefully tracked. Cooperation and training of the personnel involved in the specimen workflow (e.g. radiologists, surgeons, nurses, technicians and pathologists) are of paramount importance. The GEFPICS' update of the recommendations herein details and comments the different steps of the pre-analytical process. Application of these guidelines and participation to quality insurance programs are mandatory to ensure the correct evaluation of oncotheranostic biomarkers.
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Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Receptor ErbB-2/análise , Receptores de Esteroides/análise , Neoplasias da Mama/patologia , Feminino , Fixadores , França , Técnicas Histológicas , Humanos , Prognóstico , Controle de Qualidade , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Manejo de Espécimes/métodosRESUMO
International guidelines on HER2 determination in breast cancer have just been updated by the American Society of Clinical Oncology (ASCO) and College of American Pathologists (CAP), on the basis of more than ten-year practice, results of clinical trials and concordance studies. The GEFPICS group, composed of expert pathologists in breast cancer, herein presents these recommendations, adapted to the French routine practice. These guidelines highlight the possible diagnosis difficulties with regards to HER2 status determination, such as intra-tumor heterogeneity, special histological subtypes and biomarker re-evaluation during metastatic relapse. Pre-analytical issues and updated scoring criteria (especially for equivocal cases) are detailed, in order to decrease the occurrence of false negative cases. In the era of personalized medicine, pathologists are more than ever involved in the quality of oncotheranostic biomarker evaluation.
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Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Receptor ErbB-2/análise , Neoplasias da Mama/tratamento farmacológico , Reações Falso-Negativas , Feminino , França , Humanos , Imuno-Histoquímica/métodos , Hibridização In Situ , Hibridização in Situ Fluorescente , Metástase Neoplásica/patologia , Recidiva Local de Neoplasia , PrognósticoRESUMO
BACKGROUND: Until now, FISH has been the gold standard technique to identify HER2 amplification status in ambiguous cases of breast cancer. Alternative techniques have been developed to increase the capacities of investigating HER2 amplification status. The aims of this multicenter study in a large series of breast cancer patients were to prospectively compare the level of performance of CISH, SISH, and qPCR alternative techniques on paraffin-embedded core biopsies with "gold standard FISH" for evaluation of HER2 amplification status. METHODS: This study was performed on 840 cases scored by immunohistochemistry (IHC): 0=317 (38%), 1+=183 (22%), 2+=109 (13%), 3+=231 (27%). Each of the 15 French centers participating in the study analyzed 56 breast carcinoma cases diagnosed on fixed paraffin-embedded core biopsies. HER2 amplification status was determined by commercially available FISH used as the reference technique with determination of the HER2/CEN17 ratio or HER2 copy number status. The alternative techniques performed on the same cases were commercially available SISH or CISH and a common qPCR method especially designed for the study including a set of 10 primer pairs: 2 for HER2 (exons 8 and 26), 5 to evaluate chromosome 17 polysomy TAOK1, UTP6, MRM1, MKS1, SSTR2 and 3 for diploidy control TSN, LAP3 and ADAMTS16. RESULTS: The concordance between IHC and FISH was 96% to 95% based on the HER2/CEN17 ratio (n=766) or HER2 copy number (n=840), respectively. The concordance of the alternative techniques with FISH was excellent: 97% and 98% for SISH (498 and 587 cases), 98% and 75% for CISH (108 and 204 cases) and 95% and 93% (699 and 773 cases) for qPCR based on the HER2/CEN17 ratio or HER2 copy number, respectively. Similarly, sensitivity ranged from 99% to 95% for SISH, 100% to 99% for CISH and 89% to 80% for qPCR. The concordance with FISH (ratio) in the 2+ cases was 89% for SISH, 100% for CISH and 93% for qPCR. CONCLUSION: These alternative techniques showed an excellent concordance with FISH in core biopsies allowing their use in routine clinical practice. This newly designed qPCR on paraffin-embedded core biopsies deserves special attention, as it is reliable, easy to perform and less expensive than ISH tests.
Assuntos
Neoplasias da Mama/genética , Genes erbB-2/genética , Hibridização In Situ/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Biópsia com Agulha de Grande Calibre , Feminino , Amplificação de Genes , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Valor Preditivo dos TestesRESUMO
Introduction: A gonadectomy is currently recommended in patients with Turner syndrome (TS) and a 45,X/46,XY karyotype, due to a potential risk of gonadoblastoma (GB). However, the quality of evidence behind this recommendation is low. Objective: This study aimed to evaluate the prevalence of GB, its characteristics, as well as its risk factors, according to the type of Y chromosomal material in the karyotype. Methods: Our study within French rare disease centers included patients with TS and a 45,X/46,XY karyotype, without ambiguity of external genitalia. Clinical characteristics of the patients, their age at gonadectomy, and gonadal histology were recorded. The regions of the Y chromosome, the presence of TSPY regions, and the percentage of 45,X/46,XY mosaicism were evaluated. Results: A total of 70 patients were recruited, with a median age of 29.5 years (21.0-36.0) at the end of follow-up. Fifty-eight patients had a gonadectomy, at a mean age of 15 ± 8 years. GB was present in nine cases. Two were malignant, which were discovered at the age of 14 and 32 years, without metastases. Neither the percentage of XY cells within the 45,X/46,XY mosaicism nor the number of TSPY copies was statistically different in patients with or without GB (P = 0.37). However, the entire Y chromosome was frequent in patients with GB (6/9). Conclusions: In our study, including a large number of patients with 45,X/46,XY TS, the prevalence of gonadoblastoma is 12.8%. An entire Y chromosome appears as the main risk factor of GB and should favor early gonadectomy. Significant statement: About 10% of patients with TS have a karyotype containing Y chromosomal material: 45,X/46,XY. Its presence is related to the risk of GB. Therefore, a prophylactic gonadectomy is currently recommended in such patients. However, the quality of evidence is low. Our objective was to evaluate the prevalence of GB according to the type of Y-chromosomal material. We found a prevalence of GB of 12.8% in a cohort of 70 TS patients. No sign of hyperandrogenism was observed. The entire Y chromosome was the most frequent type of Y-material in patients with GB. As the prognosis of these tumors was good, a delay of surgery might be discussed.
Assuntos
Gonadoblastoma , Neoplasias Ovarianas , Síndrome de Turner , Feminino , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Gonadoblastoma/epidemiologia , Gonadoblastoma/genética , Gonadoblastoma/patologia , Síndrome de Turner/epidemiologia , Síndrome de Turner/genética , Síndrome de Turner/diagnóstico , Prevalência , Seguimentos , Neoplasias Ovarianas/patologia , Cariótipo , MosaicismoRESUMO
BACKGROUND: Mammary analogue secretory carcinoma is a rare new entity of low-grade malignant tumor of salivary glands. It shared the same histologic features and the chromosomal translocation t(12;15)(p13;q25) as secretory carcinoma of the breast. AIM: To highlight the diagnosis approaches and the attitude of management in a case of MASC which is the first case reported in Tunisia. Reported case: A case of MASC of the lower left jugal mucosa was reviewed for its microscopic and immunohistochemical features. Fluorescence in situ hybridization (FISH) for the ETV6-NTRK3 translocation was performed. Surgery was the only treatment required in this case. No signs of local or regional recurrence during the one-year follow-up were noticed. COMMENTARIES: Secretory carcinoma was confused with other salivary gland tumors especially acinic cell carcinoma due to their morphological similarities, making diagnosis dilemma. Fluorescence in-situ hybridization (FISH) is the one definitive finding to confirm the diagnosis of MASC and to differentiate it from the other types of salivary gland tumor. At the present time, no specific therapy is available for patients with MASC.
Assuntos
Carcinoma Secretor Análogo ao Mamário/diagnóstico , Anoctamina-1/análise , Anoctamina-1/metabolismo , Bochecha/patologia , Análise Citogenética , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Mamoglobina A/análise , Mamoglobina A/metabolismo , Carcinoma Secretor Análogo ao Mamário/genética , Carcinoma Secretor Análogo ao Mamário/cirurgia , Mucosa Bucal/metabolismo , Mucosa Bucal/patologia , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/análise , Proteínas de Fusão Oncogênica/genética , Proteínas S100/análise , Proteínas S100/metabolismo , TunísiaRESUMO
Although fine-needle aspiration cytology (FNAC) is helpful in determining whether thyroid nodules are benign or malignant, this distinction remains a cytological challenge in follicular neoplasms. Identification of genomic alterations in cytological specimens with direct and routine techniques would therefore have great clinical value. A series of 153 cases consisting of 72 and 81 histopathologically confirmed classic follicular adenomas (cFAs) and classic follicular thyroid carcinomas (cFTCs), respectively, was studied by means of different molecular techniques in three different cohorts of patients (pts). In the first cohort (training set) of 66 pts, three specific alterations characterized by array comparative genomic hybridization (aCGH) were exclusively found in half of cFTCs. These structural abnormalities corresponded to losses of 1p36.33-35.1 and 22q13.2-13.31, and gain of whole chromosome X. The second independent cohort (validation set) of 60 pts confirmed these data on touch preparations of frozen follicular neoplasms by triple DNA fluorescent in situ hybridization using selected commercially available probes. The third cohort, consisting of 27 archived cytological samples from an equal number of pts that had been obtained for preoperative FNAC and morphologically classified as and histologically verified to be follicular neoplasms, confirmed our previous findings and showed the feasibility of the DNA FISH (DNA fluorescent in situ hybridization) assay. All together, these data suggest that our triple DNA FISH diagnostic assay may detect 50% of cFTCs with a specificity higher than 98% and be useful as a low-cost adjunct to cytomorphology to help further classify follicular neoplasms on already routinely stained cytological specimens.
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PURPOSE: Genomic tests can identify ER-positive HER2-negative localized breast cancer patients who may not benefit from adjuvant chemotherapy. Such tests seem especially interesting in "intermediate" clinico-pathological risk categories. The psychological impact of the decision uncertainty in these women remains largely unexplored. We assessed the clinical and psychological impact of EndoPredict® (EpClin), a clinico-genomic test, in these patients. METHODS: This multicenter, single arm prospective study (NCT02773004) enrolled patients for which adjuvant chemotherapy was uncertain, based on predefined criteria. The primary endpoint was the proportion of change between initial adjuvant decision and final administration of chemotherapy. Secondary endpoints included post-test (Day 17) and 1-year patient reported outcomes. RESULTS: One third of 200 evaluable patients had a high EpClin score (≥3.32867; 10 years cumulative risk of distance failure ≥10%). The overall change rate of chemotherapy decision was 72/200 (35.8%, 95% CI 29.2-42.4). Chemotherapy was withdrawn in 57 cases (28.4% [22.2-34.8]) and added in 15 (7.5% [3.8-11.2]. 6 changes (8%) were based on patients' decisions. Anxiety and distress levels increased at Day 17 when adding chemotherapy after the test result (p < 10-7 and 0.00022 respectively), while stable in other situations. At 1-year, all patients had returned to the baseline anxiety and distress levels (mean anxiety 51.5, +/- SD = 2.5 [max. 80], mean distress 3±1 [max. 10]). CONCLUSIONS: EndoPredict ® (EpClin) is clinically useful in deciding whether or not to administer adjuvant chemotherapy in patients with intermediate risk. A single-step decision is preferable since adding chemotherapy at a later stage increases anxiety and distress.
Assuntos
Neoplasias da Mama/tratamento farmacológico , Regras de Decisão Clínica , Tomada de Decisão Clínica/métodos , Genes erbB-2 , Testes Genéticos/métodos , Receptores de Estrogênio/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Ansiedade/diagnóstico , Ansiedade/etiologia , Neoplasias da Mama/genética , Neoplasias da Mama/psicologia , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Feminino , Marcadores Genéticos , Genômica , Humanos , Mastectomia , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Angústia Psicológica , Medição de Risco , IncertezaRESUMO
PURPOSE: For localized, resectable neuroblastoma without MYCN amplification, surgery only is recommended even if incomplete. However, it is not known whether the genomic background of these tumors may influence outcome. PATIENTS AND METHODS: Diagnostic samples were obtained from 317 tumors, International Neuroblastoma Staging System stages 1/2A/2B, from 3 cohorts: Localized Neuroblastoma European Study Group I/II and Children's Oncology Group. Genomic data were analyzed using multi- and pangenomic techniques and fluorescence in-situ hybridization in 2 age groups (cutoff age, 18 months) and were quality controlled by the International Society of Pediatric Oncology European Neuroblastoma (SIOPEN) Biology Group. RESULTS: Patients with stage 1 tumors had an excellent outcome (5-year event-free survival [EFS] ± standard deviation [SD], 95% ± 2%; 5-year overall survival [OS], 99% ± 1%). In contrast, patients with stage 2 tumors had a reduced EFS in both age groups (5-year EFS ± SD, 84% ± 3% in patients < 18 months of age and 75% ± 7% in patients ≥ 18 months of age). However, OS was significantly decreased only in the latter group (5-year OS ± SD in < 18months and ≥ 18months, 96% ± 2% and 81% ± 7%, respectively; P = .001). In < 18months, relapses occurred independent of segmental chromosome aberrations (SCAs); only 1p loss decreased EFS (5-year EFS ± SD in patients 1p loss and no 1p loss, 62% ± 13% and 87% ± 3%, respectively; P = .019) but not OS (5-year OS ± SD, 92% ± 8% and 97% ± 2%, respectively). In patients ≥ 18 months, only SCAs led to relapse and death, with 11q loss as the strongest marker (11q loss and no 11q loss: 5-year EFS ± SD, 48% ± 16% and 85% ± 7%, P = .033; 5-year OS ± SD, 46% ± 22% and 92% ± 6%, P = .038). CONCLUSION: Genomic aberrations of resectable non-MYCN-amplified stage 2 neuroblastomas have a distinct age-dependent prognostic impact. Chromosome 1p loss is a risk factor for relapse but not for diminished OS in patients < 18 months, SCAs (especially 11q loss) are risk factors for reduced EFS and OS in those > 18months. In older patients with SCA, a randomized trial of postoperative chemotherapy compared with observation alone may be indicated.
Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 1 , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Fatores Etários , Ensaios Clínicos como Assunto , Diploide , Amplificação de Genes , Genômica , Humanos , Lactente , Estadiamento de Neoplasias , Neuroblastoma/patologia , Neuroblastoma/cirurgia , Prognóstico , Intervalo Livre de Progressão , Taxa de SobrevidaRESUMO
Tetragametic chimeras are due to the fusion of 2 different zygotes after fertilization. When occurring between embryos of different chromosomal sex, the phenotype ranges from fertile individuals to infertile patients and even to patients with variations in sex development. Here, we report 3 new cases of XX/XY chimeras, one in a young boy carrying an abnormal gonad which turned out to be an ovary and 2 in phenotypically normal infertile men, one of whom had been diagnosed previously as a XX-SRY negative male. These cases highlight the importance of combining several cytogenetic and molecular techniques on different tissues for a proper diagnosis and an appropriate prognosis.
RESUMO
Malignant gliomas and childhood ependymomas have a high rate of treatment failure. Epidermal growth factor receptor (EGFR) activation has been implicated in the tumorigenesis and radioresistance of many cancers, including brain tumors. Therefore, combining EGFR targeting with irradiation is a potentially attractive therapeutic option. We evaluated the tyrosine kinase inhibitor gefitinib for its antitumor activity and potential to radio-sensitize in vivo in two xenograft models: an EGFR amplified glioma and an EGFR expressing ependymoma, both derived from primary tumors. When administered at 100 mg/kg for 5 consecutive days, gefitinib-induced partial tumor regression in all treated EGFR amplified IGRG88 glioma xenografts. The addition of 1 Gy of irradiation prior to gefitinib administration resulted in 5 complete and 4 partial regressions for the 9 treated tumors as well as a significant tumor growth delay of 33 days for the combined treatment compared to 19 days for each therapy alone, suggesting additive antitumor activity. Tumor regression was associated with inhibition of AKT and MAPK pathways by gefitinib. In contrast, the ependymoma IGREP83 was sensitive to irradiation, but remained resistant to gefitinib. Combined treatment was associated with inhibition of radiation-induced MAPK phosphorylation and significant induction of apoptotic cell death though radiation-induced AKT phosphorylation was maintained. Depending on the scheduling of both therapies, a trend towards superior antitumor activity was observed with combined treatment. Thus, EGFR targeting through tyrosine kinase inhibition appears to be a promising new approach in the treatment of EGFR-driven glioma, particularly in combination with radiation therapy.
Assuntos
Antineoplásicos/farmacologia , Apoptose , Ependimoma/tratamento farmacológico , Ependimoma/radioterapia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Glioma/tratamento farmacológico , Glioma/radioterapia , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Radiossensibilizantes/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Western Blotting , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Quimioterapia Adjuvante , Criança , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/efeitos da radiação , Ependimoma/patologia , Receptores ErbB/genética , Feminino , Citometria de Fluxo , Fase G1/efeitos dos fármacos , Gefitinibe , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Glioma/patologia , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Quinases de Proteína Quinase Ativadas por Mitógeno/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Radioterapia Adjuvante , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
DDX1, a gene mapping to the 2p24 region, has been observed to be co-amplified with MYCN in neuroblastoma. Co-amplification of the DDX1 gene is a consequence of the short physical distance between the two genes. Recently, it has been found that neuroblastoma cells can show a low increase in MYCN gene copy number, defined as MYCN gain. We studied 13 neuroblastomas with MYCN gain to evaluate the status of the DDX1 gene. We investigated DDX1/MYCN gain by double-colour FISH on interphase nuclei. All cases showed concomitant low extra copy number of DDX1 and MYCN. Heterogeneous distribution of nuclei displaying DDX1/MYCN gain was observed in almost all tumours, suggesting a clonal evolution of cells with DDX1/MYCN gain. This is the first report that shows DDX1 co-gained with MYCN in neuroblastoma and indicates that DDX1 over-representation is closely associated with an increase in MYCN copy number in neuroblastoma cells. Since DDX1 has already been found co-amplified with MYCN, DDX1 gain seems to be a further rearrangement due to the physical proximity of the two genes. Moreover, all patients with DDX1/MYCN gain show a good overall survival but a high frequency of adverse events.
Assuntos
RNA Helicases DEAD-box/genética , Amplificação de Genes , Neuroblastoma/genética , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , RNA Neoplásico/genética , Dosagem de Genes , Humanos , Hibridização in Situ Fluorescente , Proteína Proto-Oncogênica N-Myc , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Células Tumorais CultivadasRESUMO
Up to 10% of patients with non-small cell lung carcinoma (NSCLC) achieve an objective response to EGFR tyrosine kinase inhibitors (EGFR-TKI) such as erlotinib or gefitinib. This rate of response is related to non-smoker status, female gender, adenocarcinoma subtype, and Asian ethnicity. Molecular analysis showed that EGFR tyrosine kinase domain somatic mutations appear to be a strong predictor of response to EGFR-TKI. The L858R point mutation and the E746-A750 deletion represent 90% of the mutations encountered in responding patients. The amplification of EGFR gene also seems to be predictive of the response to EGFR-TKI, whereas T790M point mutation induces secondary resistance to EGFR-TKI. Nevertheless, objective responses or strong long-term stabilizations are observed in patients without any EGFR abnormality. Thus, the assessment of the EGFR status in patients with NSCLC remains controversial for clinical practice. The assessment of EGFR abnormalities should be targeted to identify reliable biomarkers of the NSCLC response to EGFR-TKI. This review presents the current knowledge on predictive biomarkers of NSCLC response to EGFR-TKI and the methods available for the assessment of EGFR status.