1,721,057 research outputs found
Neuroblastoma in the first year of life. The Italian contribution to a study of the International Society of Pediatric Oncology Europe Neuroblastoma Group
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Unclassified pediatric renal stromal tumor overlapping with metanephric stromal tumor and solitary fibrous tumor with diffuse S-100 protein expression.
No full textMetanephric stromal tumor (MST) is a rare pediatric neoplasm unique to the kidneys that is currently included in the spectrum of metanephric tumors, along with metanephric adenoma and adenofibroma. We herein report an unusual case of pediatric renal stromal tumor overlapping with MST and solitary fibrous tumor (SFT). Histologically, the tumor was composed of bland-looking spindle to stellate cells embedded in a fibro-sclerotic stroma that focally surrounded native entrapped renal tubules or blood vessels with abortive rings or collarettes. Alternating hypercellular and hypocellular areas and a focal hemangiopericytomatous-like vascular pattern imparted to the tumor a resemblance to SFT. Angiodysplasia of intratumoral arterioles was also observed, but juxtaglomerular cell hyperplasia was not a feature. Immunohistochemically, the neoplastic cells showed a polyphenotypic profile, including diffuse expression of vimentin and CD34, and focal immunoreactivity for alpha-smooth muscle actin, EMA, and CD99. However, the most striking finding was diffuse nuclear and cytoplasmic expression of S-100 protein. Although this protein has been reported to stain the heterologous glial and/or cartilaginous components that can be occasionally encountered in MST, this marker has not been previously reported in the fibroblastic component of MST. Pathologist should be aware of similar unusual unclassified tumors to avoid potential confusion with other benign or malignant S-100 protein-positive tumors
Embryonal tumor with abundant neuropil and true rosettes. A new entity or only variations of a parent neoplasms (PNETs)? This is the dilemma
No full textA rare embryonal brain tumor has been diagnosed in a 4-year-old boy. The mass, located at the pons and mesencephalon, has been histologically classified as an embryonal tumor containing abundant neuropil and true rosettes. After surgical complete removal of the neoplasia, the child received intensive combined chemotherapy and radiotherapy. He is alive and free of disease at 34 months from surgery. Difficulties in histological definition, possible suggestions for treatment proposals are discussed
Integrated analysis of colorectal cancer microRNA datasets: Identification of microRNAs associated with tumor development
Full text linkColorectal cancer (CRC) is one of the leading cause of cancer death worldwide. Currently, no effective early diagnostic biomarkers are available for colorectal carcinoma. Therefore, there is a need to discover new molecules able to identify pre-cancerous lesions. Recently, microRNAs (miRNAs) have been associated with the onset of specific pathologies, thus the identification of miRNAs associated to colorectal cancer may be used to detect this pathology at early stages. On these bases, the expression levels of miRNAs were analyzed to compare the miRNAs expression levels of colorectal cancer samples and normal tissues in several miRNA datasets. This analysis revealed a group of 19 differentially expressed miRNAs. To establish the interaction between miRNAs and the most altered genes in CRC, the mirDIP gene target analysis was performed in such group of 19 differentially expressed miRNAs. To recognize miRNAs able to activate or inhibit genes and pathways involved in colorectal cancer development, DIANA-mirPath prediction analysis was applied. Overall, these analyses showed that the upregulated hsa-miR-183-5p and hsa-miR-21-5p, and the down-regulated hsa-miR-195-5p and hsa-miR-497-5p were directly related to colorectal cancer through the interaction with the Mismatch Repair pathway and Wnt, RAS, MAPK, PI3K, TGF-ß and p53 signaling pathways involved in cancer development
VALUTAZIONE QUANTITATIVA DI MALATTIA MINIMA NEL MIDOLLO E NEL SANGUE PERIFERICO DI PAZIENTI CON RABDOMIOSARCOMA MEDIANTE TECNICA DI REAL TIME PCR
No full textIntroduzione e scopo. Il Rabdomiosarcoma (RMS), tumore
a piccole cellule rotonde blu, è il più comune sarcoma dei
tessuti molli pediatrici. In circa 20% dei casi si presenta con
malattia diffusa alla diagnosi e le sedi più frequentemente
coinvolte sono polmoni, linfonodi e midollo osseo (BM).
Attualmente, l’infiltrazione midollare di cellule di RMS è
rilevata dall’ analisi morfologica dell’ aspirato midollare e/o
delle biopsie osteo-midollari. Questi metodi tuttavia non
riescono a rilevare un’infiltrazione neoplastica inferiore al
5%. Sulla base delle caratteristiche cliniche e biologiche del
RMS, abbiamo standardizzato un metodo quantitativo di
RT-PCR basato sul marcatore RMS-specifico MyoD1, al
fine di studiare la malattia minima disseminata(MMD) in
bambini con RMS. Materiali e metodi. Abbiamo condotto
studi di RT-PCR quantitativa relativa per il gene MyoD1
mediante tecnologia TaqMan. I primers specifici per
MyoD1 e la sonda sono stati individuati usando il software
specifico Primer Express (Applied Biosystems). GUS è
stato utilizzato come gene housekeeping ossia come controllo
endogeno per ogni campione. Risultati. Abbiamo studiato
il BM alla diagnosi di 39 pazienti affetti da RMS. La
metodica è di facile applicazione ed unisce l’alta sensibilità
alla specificità. MMD era positiva in 17/39 pazienti. I livelli
di espressione di MyoD1 in 7/17 campioni, positivi anche
mediante RT-PCR qualitativa, hanno mostrato valori di Ct
che variavano in un range da 21 a 27, mentre in 10 casi,
negativi in RT-PCR, il valore di Ct era superiore a 35. In 14
pazienti abbiamo potuto studiare la malattia minima anche
nel sangue periferico. 10/14 sono risultati positivi con valori
di Ct in un range da 35 a 38, indipendentemente dalla
positività midollare. Conclusioni. Questi risultati preliminari
suggeriscono che il coinvolgimento midollare alla diagnosi
è discretamente frequente in pazienti con RMS e che
la MMR può essere rilevata, anche se a livelli molto bassi,
nel sangue periferico indipendentemente dall’infiltrazione
midollare
LATE PROGRESSION OF A NEUROBLASTOMA AS A MALIGNANT SCHWANNOMA
No full textMed.Pediatr Oncol - XXXII SIOP Meetin
Results of a prospective minimal disseminated disease study in human rhabdomyosarcoma using three different molecular markers
No full textBACKGROUND:
Rhabdomyosarcoma (RMS) has 2 major histologic subtypes: alveolar (ARMS) and embryonal (ERMS). ARMS is more aggressive and prone to distant tumor dissemination, whereas ERMS tends to expand and recur locally. Little information is available on bone marrow involvement by RMS.
METHODS:
We determined the sensitivity and specificity of MyoD1, myogenin, and PAX-FKHR transcripts as RMS markers and used them to study prospectively by reverse-transcriptase polymerase chain reaction (RT-PCR) a series of consecutive unselected RMS patients enrolled in the Italian Association of Pediatric Hematology and Oncology national trial. Prevalence of minimal disseminated disease (MDD) and its response kinetics to chemotherapy were assessed.
RESULTS:
MyoD1 and myogenin were specifically associated with RMS, independently of histologic subtype, whereas PAX3/7-FKHR transcripts were expressed only in ARMS. Sensitivity was higher for MyoD1 compared with myogenin and PAX-FKHR. Out of a cohort of 40 patients, MDD positivity was limited to ARMS, with the sole exception of 1 ERMS. Prevalence of MDD positivity increased when a real-time polymerase chain reaction approach was used on a subgroup of patients. RT-PCR was more sensitive than microscopic examination of bone marrow biopsies. The study of the response kinetics of MDD showed that in approximately half of the cases, bone marrow was cleared of disease after 1 cycle of chemotherapy.
CONCLUSIONS:
MyoD1 and myogenin transcripts can be used as tumor markers for MDD assessment in virtually all RMS cases, whereas PAX-FKHR is specific for ARMS. Sensitivity of RT-PCR methods was superior compared with standard morphologic assays. Our study suggests that bone marrow involvement is more common in ARMS compared with ERMS, and that MDD can be often cleared by the initial chemotherapy cycles
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