Blue Cell Tumors Of Childhood Research Articles

Use of Immunohistochemistry in the differential diagnosis of Small Round Blue cell tumors.

Objectives: Objective of the study is to differentiate and sub-categorize malignant small round blue cell tumors by using immune-histochemistry. Study Design: Descriptive Observational study. Setting: Meezan Private Lab, Faisalabad, Pakistan. Period: 5 years, from July 2014 to June 2019. Material & Methods: Sample Size: 126 cases of Round blue cells tumors. Sampling Technique: Non probability purposive sampling. Data Collection Procedure: 126 cases which fulfilled the inclusion and exclusion criteria were selected for the study. All these cases were subjected to immunohistochemistry. The IHC technique used was based on Peroxidase anti-peroxidase (PAP) method. Based on site and morphological clues, initially Leukocyte common antigen (LCA), Myogenin, Cytokeratin (CK), Desmin, chromogranin, Neuron specific enolase (NSE), S-100, Smooth muscle actine (SMA) and CD99 were used. Further immune stains panels were used afterwards, as and when needed like CD20, CD3, CD30, BCL2, CD117, Ki-67, Tdt, synaptophysin, SMA, CD56, Melan A, HMB45 and WT1. Results: Out of 126 cases of small round blue cell tumors, 35 (27.8 %) cases were diagnosed as diffuse large B cell lymphoma, 6 as Lymphoblastic lymphoma, 4 as Burkitt’s lymphoma, and 6 cases as NK/T cell lymphoma. Ewing’s sarcoma/PNET (12/126, 9.5%) was the 2nd highest in frequency, followed by Rhabdomyosarcoma, Synovial sarcoma, Malignant melanoma, and Germ cell tumor, which were all 9/126 each with 7.1 %. Conclusion: Immunohistochemistry is an important tool for appropriate and clear differential diagnosis of malignant small round blue cell tumors of childhood.

Rhabdomyosarcoma and Extraosseous Ewing Sarcoma.

Rhabdomyosarcoma (RMS) is a malignant tumor that represents the most common form of pediatric soft tissue sarcoma. It arises from mesenchymal origin and forms part of the group of small round blue cell tumors of childhood. It has a constant annual incidence of 4.5 cases per 1,000,000 children. The known histological diagnosis of the two major subtypes (embryonal and alveolar) has been recently enhanced by tumor biological markers and molecular differentiation diagnostic tools that have improved not only the updated classification based on risk stratification, but also the treatment approach based on the clinical group. Ewing sarcoma (ES) is a round cell tumor, highly malignant and poorly differentiated that is currently the second most common malignant bone tumor in children. In rare instances, it develops from an extraskeletal origin, classified as extraosseous Ewing sarcoma (EES). We provide an updated, evidence-based and comprehensive review of the molecular diagnosis, clinical and diagnostic approach and a multidisciplinary medical and surgical management according to the latest standard of care for the treatment of pediatric RMS and EES.

Immunohistochemical characterization of small round blue cell tumors of childhood at Ile-Ife, Nigeria: A 10-Year retrospective study

Background: Immunostains when used in correlation with clinical site of tumours and morphology permits accurate and specific diagnosis of these undifferentiated tumours. Materials and Methods: A ten-year retrospective research of the histopathological and immunohistochemical features of small round blue cell tumours (SRBCT) in OAUTHC was analyzed. Pathology reports of all SRBCT and their blocks were retrieved and recut slides reviewed to determine each tumour types. Acute myelocytic lymphoma/leukeamias and Glioblastoma multiformis were excluded from SRBCT of childhood. Eighty four (84) cases that fulfilled the inclusion criteria were analyzed using immunohistochemistry. Results: The age range of presentation was 0-15 years (Mean 5.98±3.964 year S.D.). Retinoblastoma and Wilms' tumours were the commonest histological sub-types with a percentage of 20.0% each followed by Burkitt lymphoma (17.6%), rhabdomyosarcoma (9.8%) which was the only soft tissue sarcoma found. The least represented was supra-tentorial CNS-PNET (1.2%). Eighty four blocks of SRBCT were subjected to different panels of immunohistochemistry. Of all these tumours 36 cases had a change in diagnosis: 23 cases had an initial, pre-immunohistochemical umbrella diagnosis ranging from NHL, SRBCT to no pathological diagnosis at all. Seven (7) cases with initial diagnosis ranging from Ewing's sarcoma (1 case), retinoblastoma (1 case) to rhabdomyosarcoma (5 cases) were finally confirmed with immunostains as Burkitt lymphoma (BL) while one case of BL was finally confirmed as rhabdomyosarcoma. The last five of the 36 cases were totally non-neoplastic lesions but had histology diagnosis ranging from NHL, spinal cell sarcoma to periosteal osteosarcoma. The immunostains done on these 5 cases revealed erythroid hyperplasia with dyserythropoiesis, cellular neurofibroma, fibrous dysplasia, reactive follicular hyperplasia and normal retinal tissue. Conclusion: Application of immunohistochemistry does indeed enhance the diagnostic accuracy of these undifferentiated tumors.

Phylogeny of Wilms tumor?

Phylogeny of Wilms tumor?

Diagnostic utility of PHOX2B in primary and treated neuroblastoma and in neuroblastoma metastatic to the bone marrow.

Neuroblastoma (NB) is the most common extracranial tumor of childhood. Although most cases have a distinctive histology, a subset of primitive cases require immunohistochemical studies to distinguish them from other small round blue cell tumors of childhood. Immunohistochemistry is also used to detect small amounts of tumor metastatic to the bone marrow and in posttreatment samples with obscuring fibrosis, calcification, or inflammation. The transcription factor PHOX2B is essential for the differentiation and survival of sympathetic neurons and chromaffin cells, and therefore is highly specific for the peripheral autonomic nervous system. To determine the diagnostic utility of PHOX2B immunohistochemistry as a marker of primary, treated, and metastatic NB. Neuroblastoma tissue microarrays were stained with PHOX2B, CD57, and synaptophysin. Arrays containing rhabdomyosarcoma, Ewing sarcoma, and Wilms tumor were stained with PHOX2B, and negative bone marrow samples were stained with PHOX2B and CD57. PHOX2B and CD57 were similar to synaptophysin in their ability to detect NB. PHOX2B and CD57 similarly showed robust staining in posttreatment NB and NB metastatic to the bone marrow. In contrast to the cytoplasmic staining pattern seen with synaptophysin and CD57, clear and strong nuclear PHOX2B permitted identification of individual tumor cells. PHOX2B staining was absent in all cases of rhabdomyosarcoma, Ewing sarcoma, and Wilms tumor, and in the negative bone marrow. PHOX2B and CD57 are useful markers of NB. PHOX2B is specific for NB in its differential diagnosis with other small round cell tumors, and its nuclear staining may be helpful for accurate bone marrow tumor quantification.

Abstract 1137: Next generation sequencing of the neuroblastoma transcriptome identifies multiple protein disrupting mutations

Abstract Introduction: Neuroblastoma (NB) is one of the small round blue cell tumors of childhood arising in the peripheral nervous system. Fifty percent of patients present with metastatic or high risk disease and despite aggressive multimodal therapy approximately 60% percent of these patients eventually succumb to NB. Currently only a handful of molecular alterations are known to influence prognosis, but no clear mechanism of pathogenesis has been demonstrated. Recently, targeted sequencing efforts identified recurrent single nucleotide variants (SNVs) in the ALK gene in 6.1-15% of NB. In an effort to better understand the biology driving this tumor and to identify new targets for therapy, we sequenced the transcriptomes of 20 stage four tumors, including ten MYCN amplified and ten MYCN non-amplified samples, using massively parallel sequencing technology. Methods: In our analysis pipeline, 50 base nucleotide reads are filtered against a database of rRNA, tRNA, repetitive regions, and adapter sequences. The remaining reads were aligned to the reference human genome (hg 18) and a database of spice junctions. Reads that align were analyzed for: 1) base coverage, 2) transcript expression levels, 3) calling SNVs and 4) determination of which of the SNVs were damaging by Sorting Intolerant From Tolerant (SIFT) analysis Results: Initial analysis of the first six samples, yielded an average of 86.6 million uniquely mapped reads per sample. On average we detected the expression of 6,000 genes to a depth of 10x. The RNA seq expression profile correlated well with expression array data from the same sample (r=0.62), while the sequencing data identified an additional 3,000 genes that were not detected by microarray. Our sequencing method maintains “strandedness” allowing the identification of multiple novel antisense non-coding transcripts. Using the SAMtool, an average of 1,255 nonsynonymous SNVs predicted per sample. Of these nonsynonymous SNVs, 69-160 per sample were predicted by the SIFT algorithm to be damaging. Interestingly, 3 different genes had damaging nonsynonymous SNVs in at least 30% of the samples. Conclusion: Next generation sequencing of transcriptome is a powerful and more sensitive method than microarrays for expression profiling and allows for the identification of novel transcripts including non-coding RNAs. Here we report the most extensive profiling of the neuroblastoma transcriptome to date using this technology. We identified several hundred protein disrupting SNVs, and of these 3 were commonly altered. Ongoing analysis is underway to validate our results. The identification of recurrent genetic alterations in NB will assist in developing a better understanding of the mechanisms of pathogenesis of this pediatric cancer and lead to new therapeutic targets. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1137.

A new regularized least squares support vector regression for gene selection

BackgroundSelection of influential genes with microarray data often faces the difficulties of a large number of genes and a relatively small group of subjects. In addition to the curse of dimensionality, many gene selection methods weight the contribution from each individual subject equally. This equal-contribution assumption cannot account for the possible dependence among subjects who associate similarly to the disease, and may restrict the selection of influential genes.ResultsA novel approach to gene selection is proposed based on kernel similarities and kernel weights. We do not assume uniformity for subject contribution. Weights are calculated via regularized least squares support vector regression (RLS-SVR) of class levels on kernel similarities and are used to weight subject contribution. The cumulative sum of weighted expression levels are next ranked to select responsible genes. These procedures also work for multiclass classification. We demonstrate this algorithm on acute leukemia, colon cancer, small, round blue cell tumors of childhood, breast cancer, and lung cancer studies, using kernel Fisher discriminant analysis and support vector machines as classifiers. Other procedures are compared as well.ConclusionThis approach is easy to implement and fast in computation for both binary and multiclass problems. The gene set provided by the RLS-SVR weight-based approach contains a less number of genes, and achieves a higher accuracy than other procedures.

Diagnosis of the Small Round Blue Cell Tumors Using Multiplex Polymerase Chain Reaction

The small round blue cell tumors of childhood, which include neuroblastoma, rhabdomyosarcoma, non-Hodgkin's lymphoma, and the Ewing's family of tumors, are so called because of their similar appearance on routine histology. Using cDNA microarray gene expression profiles and artificial neural networks (ANNs), we previously identified 93 genes capable of diagnosing these cancers. Using a subset of these, together with some additional genes (total 39), we developed a multiplex polymerase chain reaction (PCR) assay to diagnose these cancer types. Blinded testing of 96 new samples (26 Ewing's family of tumors, 29 rhabdomyosarcomas, 24 neuroblastomas, and 17 lymphomas) using ANNs in a complete leave-one-out analysis demonstrated that all except one sample were accurately diagnosed as their respective category. Moreover, using an ANN-based gene minimization strategy in a separate analysis, we found that the top 31 genes could correctly diagnose all 96 tumors. Our results suggest that this molecular test based on a multiplex PCR reaction may assist the physician in the rapid confirmation of the diagnosis of these cancers.

Ovarian Neoplasms Composed of Small Round Cells

Ovarian neoplasms composed predominantly or exclusively of small round cells with scant cytoplasm are relatively rare. However, there is a wide differential, and pathologists often struggle to make a correct diagnosis because of overlapping histologic features. Perhaps the best known of these neoplasms is ovarian small cell carcinoma of hypercalcemic type (OSCCHT), a tumor of unknown histogenesis. This may be confused with a wide range of neoplasms ranging from sex cord-stromal tumors (some of which may exhibit a small cell phenotype) to neoplasms in the family of small round blue cell tumors to various undifferentiated malignancies. A neuroendocrine small cell carcinoma, so-called small cell carcinoma of pulmonary type, may also arise within the ovary, and this may be a component of a typical ovarian surface epithelial-stromal tumor. In addition to the well-known family of small round blue cell tumors of childhood, other small cell neoplasms that may arise within the ovary or involve the ovary include intra-abdominal desmoplastic small round cell tumor, metastatic small cell carcinoma, peripheral and central primitive neuroectodermal tumor, and endometrial stromal sarcoma. Malignant melanoma, undifferentiated carcinoma, and various germ cell tumors, especially dysgerminoma and immature teratoma, also on occasion enter into the differential diagnosis of an ovarian small cell neoplasm. In this review, the morphologic features of some of these neoplasms are described, as is the value of immunohistochemistry and other ancillary techniques in establishing a diagnosis.

Immunohistochemistry of Small Round Blue Cell Tumors of Childhood

Small round blue cell tumors in childhood represent a diagnostic category of tumors that show no distinguishing morphologic features but require accurate identification because of their requirement for specific therapies and different clinical outcomes. While the use of ancillary investigations such as cell culture, cytogenetics, and molecular analysis has contributed to their identification and our understanding of their pathogenesis, electron microscopy and immunohistology have proven to be the most practical diagnostic tool in this category of tumors. In the majority of cases, a carefully selected panel of antibodies allows the identification of rhabdomyosarcoma, leukemia/lymphoma, neuroblastoma, Ewing's sarcoma/peripheral neuroepithelial tumors, desmoplastic small round cell tumor, and mesenchymal chondrosarcoma. Although no single antibody is specific, the combination of a number of positive and negative markers produces an immunohistochemical profile that is relatively specific to each of these tumors. To aid understanding of the immunophenotype and histogenesis, molecular aspects of each lesion is briefly discussed. (The J Histotechnol 22:239, 1999)

Tracheobronchial mucoepidermoid carcinoma in childhood and adolescence: case report and review of the literature

In children and adolescents, primary neoplasms of the tracheobronchial tree and lungs are rare, with most tumors involving the respiratory system being metastatic, small, blue cell tumors of childhood. Of the primary pulmonary neoplasms, most are malignant with mucoepidermoid carcinoma representing about 10% of these malignant tumors. We present an 8-year-old Hispanic male with hemoptysis and several episodes of pneumonia which initially was thought to be infectious upon biopsy during bronchoscopy, but proved to be mucoepidermoid carcinoma of the tracheobronchial tree by microscopic examination during an open lung biopsy. This rare tumor is more common in adults than in children, and infrequently presents with hemoptysis. Mucoepidermoid tumors of the tracheobronchial tree carry a more favorable prognosis in children than adults. In the adult population, the overall mortality is slightly less than 30%. In contrast, of the 31 reported cases of tracheobronchial mucoepidermoid carcinoma in pediatrics, all children are free of tumor involvement with a mean follow-up period of 5.8 years (range, 0.7–21 years). Based upon the available clinical outcome and survival data, it would appear that tracheobronchial mucoepidermoid carcinoma may be successfully managed by surgical intervention alone in children and adolescents.

The Ewing's sarcoma family of tumors: Ewing's sarcoma and peripheral primitive neuroectodermal tumor of bone and soft tissue.

In 1921 James Ewing described a radiosensitive tumor of the forearm composed of small round cells that he believed to be of endothelial origin [1]. These small round cell tumors of bone came to be known as Ewing’s sarcomas. Soft tissue variants are called extraosseous Ewing’s sarcoma [2, 3] and the Askin tumor [4]. Bone and soft tissue tumors, which are quite similar to Ewing’s sarcoma under the light microscope but which have notable neural differentiation, have been denoted peripheral primitive neuroectodermal tumors (PNETs) or peripheral neuroepithelioma. The distinction between Ewing’s sarcoma of bone and soft tissue and other small round blue cell tumors of childhood was essentially a diagnosis of exclusion until current immunohistochemical and molecular genetic techniques gave us tools to better delineate these tumors. These tumors are defined by a common molecular marker, the (11;22)(q24;q12) translocation, or its variants. It is now thought that these tumors are all related and compose a spectrum of neuroepithelial tumors ranging from the least differentiated (Ewing’s sarcoma) to the most differentiated variants (PNET). It has been suggested that these tumors be considered a family of tumors called the Ewing’s sarcoma family of tumors (ESFT).KeywordsTotal Body IrradiationDesmoplastic Small Round Cell TumorSmall Round Cell TumorPeripheral Primitive Neuroectodermal TumorEwing Family TumorThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Fine-needle aspiration biopsy of childhood rhabdomyosarcoma: reevaluation of the cytologic criteria for diagnosis.

The distinction between rhabdomyosarcoma (RMS) and the other small round blue cell tumors of childhood has therapeutic implications which stress the importance of a correct diagnosis. In attempts to reevaluate the cytologic criteria of this entity, we reviewed a series of 17 fine-needle aspiration biopsies and three touch imprints from soft tissue masses. All cases had been histologically confirmed except for two cases that only had immunocytochemical and ultrastructural confirmation. The features occurring most commonly include a uniform population of tumor cells arranged as single cells and cohesive aggregates. The cells were predominantly round/polygonal, with uniform nuclei and scant to moderate amounts of cytoplasm. The nuclear chromatin was most often finely granular and hyperchromatic, while nucleoli were inconspicuous. Binucleated and multinucleated cells were found in 17 of the 20 smears. Intracytoplasmic vacuoles were present in 17 cases, ranging from occasional in one case, a few in 10 cases, and very numerous in six cases. We conclude that the presence of bi/multinucleated cells is an important clue for the diagnosis of RMS on fine-needle aspiration biopsy.

Ewing's sarcoma—Routine diagnostic utilization of MIC2 analysis: A pediatric oncology group/children's cancer group intergroup study

Ewing's sarcoma and peripheral neuroectodermal tumor (PNET) are small blue cell tumors with no reliable positive diagnostic markers. However, Ewing's sarcoma and PNET recently have been shown to strongly express an antigen determined by the MIC2 gene, whereas other blue cell tumors of childhood for the most part do not. MIC2 analysis therefore offers a distinctive addition to the panel of immunohistochemical stains used to differentiate among small blue cell tumors of childhood, since it represents the first positive marker for Ewing's sarcoma and PNET. This study addresses the reliability of MIC2 analysis using the monoclonal antibody 12E7 on tumors registered in the current Intergroup Ewing's Sarcoma protocol. Of 244 tumors, 221 (91%) showed a diffuse strong membranous pattern. The antibody appears to withstand all the fixation variables inherent in a multi-institutional study. We conclude that MIC2 expression is highly reliable as a positive marker for the Ewing's sarcoma/PNET family of tumors when the results are interpreted in the total context with clinical and pathologic parameters.

Fine-needle aspiration biopsy of small round blue cell tumors of childhood : BE McGahey, AT Moriarty, WA Nelson, MT Hull. Cancer 69:1067–1073, 1992

Fine-needle aspiration biopsy of small round blue cell tumors of childhood : BE McGahey, AT Moriarty, WA Nelson, MT Hull. Cancer 69:1067–1073, 1992

Fine-needle aspiration biopsy of small round blue cell tumors of childhood.

One hundred twenty-eight palpable and deep-seated fine-needle aspiration biopsies (FNAB) were done on pediatric patients at James Whitcomb Riley Hospital for Children and Indiana University Hospital between 1985 and 1988. During that 4-year period, 71 (56%) benign and 49 (38%) malignant diagnoses were made. Only eight (6%) of the FNAB were considered inadequate. Thirty-nine (80%) of the malignant aspirates were small round blue cell tumors of childhood (SRBCT). The SRBCT consisted of 21 (54%) lymphomas, 7 (18%) Ewing's sarcomas, 3 (8.5%) neuroblastomas, 3 (8.5%) rhabdomyosarcomas, 2 (5.0%) medulloblastomas, 2 (5.0%) Wilms' tumors, 1 (3.0%) retinoblastoma, and 1 (3%) granulocytic sarcoma. Fifteen (38%) of the SRBCT aspirates were obtained to render a primary diagnosis and 24 (62%) documented recurrence. Various combinations of electron microscopy, immunocytochemistry, and other special stains were used to confirm the diagnosis in 11 (28%) cases. These cases consisted of five lymphomas, two rhabdomyosarcomas, two Ewing's sarcomas, one neuroblastoma, and one granulocytic sarcoma. The technique of FNAB is a successful diagnostic tool for documenting primary and recurrent SRBCT in a pediatric population.

Melanotic Neuroectodermal Tumor of Infancy Occurring in the Left Thigh of a 6-Month-Old Female Infant

We report an exceptional case of melanotic neuroectodermal tumor of infancy (MNTI) occurring in the soft tissue of the left thigh of a 6-month-old female infant. The tumor consisted mainly of small round cells (neuroblasts) arranged in cords and nests that were separated by broad fibrovascular areas. In addition, there were a few medium-sized tumor cells containing melanin pigment (melanocytic cells) that in electron microscopy contained melanosomes as well as tonofilaments. Both tumor cell types immunostained for neuron-specific enolase (NSE) and vimentin, and the melanocytic cells reacted additionally with the antikeratin antibody KL1. Within the tumor stroma, neurofilament- and S-100-protein-positive neural cells and vimentin- and desmin-positive myofibroblasts were seen. Although dense-core granules were demonstrated ultrastructurally in some neuroblasts, no immunostaining for chromogranin A, Leu-7, serotonin, or regulatory peptides was found. MNTI located in an extremity can be confused with malignant small round and blue cell tumors of childhood. The distinction between MNTI and these tumors is of clinical significance because MNTI, in most cases, is a benign tumor that, in contrast to the latter, can be cured by complete excision. The presence of a biphasic cell population with neuroblasts and melanocytic cells must be considered the main diagnostic feature of MNTI.