bromochloroacetic-acid and Neuroectodermal-Tumors--Primitive

Ewing's sarcoma/primitive neuroectodermal tumor (PNET) has been the subject of recent reports describing morphologic variants (adamantinoma-like, large cell, spindle cell, sclerosing, clear cell, and vascular-like) of the most classic form, as well as cases displaying unusual morphologic differentiation and atypical immunohistochemical features. We report a case of an uncommon lung tumor in a 20-year-old female, morphologically and molecularly consistent with an Ewing's sarcoma/PNET tumor with foci of squamous differentiation, and peculiar expression of vimentin, high-molecular-weight keratins, p63, synaptophysin, and chromogranin. This case raises a challenging differential diagnostic problem with therapeutic implications: Should the patient be treated following the protocols for Ewing's sarcoma/PNET tumors or as for lung carcinoma with neuroendocrine features? The patient we report here was treated with neoadjuvant chemotherapy for Ewing's sarcoma/PNET according to Euro Ewing 99 study protocol followed by surgery and has no evidence of disease 15 months after the initial diagnosis. This highlights the importance of achieving the correct diagnosis of these atypical tumors using all clinical, morphological, and ancillary methods available to allow for their correct and timely treatment.

Topics: Antigens, CD; Biomarkers, Tumor; Female; Humans; Keratins; Lung Neoplasms; Neuroectodermal Tumors, Primitive; Vimentin; Young Adult

To define the maturational sequence of 3 infantile intraocular medulloepitheliomas.. Retrospective clinicohistopathologic and immunohistochemical study.. Immunoreactivity of paraffin sections for CRX (cone-rod homebox transcription factor) and NeuN (biomarker for neuronal differentiation) were investigated together with other biomarkers, including S100, glial fibrillary acidic protein, epithelial membrane antigen, and various cytokeratins.. Three infants (aged 1, 6, and 8 months) had iris neovascularization, 2 had anterior ciliary body tumors, and 1 a posterior tumor associated with a retinochoroidal coloboma. Each tumor displayed a premedullary monolayer of cuboidal epithelium that was S100(+), NeuN(-), and CRX(-) and that transitioned into a multilaminar medullary epithelium forming neurotubules with adluminal cells that were CRX(+). NeuN first appeared in ablumenal neurotubular cells in 1 tumor and was also discovered among neuroblast-appearing cells in another. The third tumor associated with a coloboma was CRX(-) and NeuN(-).. A simple premedullary epithelial monolayer appears to be the fundamental source for the tumor and its multilaminar medullary epithelium. CRX(+) and NeuN(+) cells within the multilayered medullary layer approximate expression patterns similar to those found in retinal development and differentiation. Discovery of these biomarkers in the neoplastic ciliary epithelium in a small number of tumors indicates preliminarily that the most anterior layers of the optic cup have a retained retinal and neuroglial differentiation potentiality. The third case was CRX(-) and NeuN(-) and possibly arose from embryonic pigment epithelium at the edge of the retinochoroidal coloboma. These immunohistochemical findings offer histogenetic and potential diagnostic insights.

Topics: Antigens, Nuclear; Biomarkers, Tumor; Choroid; Ciliary Body; Coloboma; Female; Glial Fibrillary Acidic Protein; Homeodomain Proteins; Humans; Immunoenzyme Techniques; Infant; Infant, Newborn; Keratins; Male; Mucin-1; Nerve Tissue Proteins; Neuroectodermal Tumors, Primitive; Retina; Retinal Neoplasms; Retrospective Studies; S100 Proteins; Trans-Activators; Uveal Neoplasms

Ewing sarcoma (ES)/ primitive neuroectodermal tumour (PNET) is an aggressive malignant neoplasm affecting mainly children and young adults. The tumour is included with other primitive neoplasms under the category of small round cell tumour. Cytokeratin expression in ES/PNET has been described in sporadic case reports as well as a few systemic series. We studied this feature in Malaysian patients diagnosed in University Malaya Medical Centre on the basis of typical morphology and immunohistochemical assays. Immunohistochemical staining for AE1/AE3 and MNF116 were performed in 43 cases. Cytokeratin was expressed in 17 cases (39.5%) in focal, intermediate or diffuse patterns. There was no significant association between cytokeratin immunoreactivity and the following parameters: patient age, sex, skeletal and extraskeletal primary location as well as primary, metastastic or recurrent tumours or chemotherapy treatment. A significant association between cytokeratin and neuron specific enolase (NSE) expression was demonstrated. Our study supports evidence of epithelial differentiation in ES/PNET and emphasizes that the expression of cytokeratin does not exclude ES/PNET in the differential diagnosis of small round cell tumours.

Topics: Adolescent; Adult; Aged; Biomarkers, Tumor; Child; Child, Preschool; Female; Humans; Immunohistochemistry; Keratins; Malaysia; Male; Middle Aged; Neuroectodermal Tumors, Primitive; Sarcoma, Ewing; Young Adult

To study the clinicopathologic features, immunohistochemical findings, diagnosis and differential diagnosis of atypical teratoid/rhabdoid tumors (AT/RT) of central nervous system in childhood.. The clinicopathologic data, morphologic features and immunophenotypes were reviewed in 6 cases of AT/RT. EnVision method was applied. Antibodies include cytokeratin (CK), epithelial membrane antigen (EMA), vimentin, smooth muscle actin (SMA), muscle specific actin (MSA), glial fibrinary acid protein (GFAP), desmin, placental alkaline phosphatase (PLAP) and INI1.. Five of the six cases of AT/RT occurred in infancy and early childhood. Histologically, the predominant component was rhabdoid cells. Cytoplasmic inclusions were present in all cases. Primitive neuroectodermal tumor (PNET) component was also identified in 5 of the 6 cases studied. Immunohistochemically, the tumor cells were positive for cytokeratin, epithelial membrane antigen and vimentin. The staining for INI1, desmin and PLAP was negative. Smooth muscle actin was expressed in 2 cases and glial fibrillary acidic protein in 5 cases. The proliferative index as demonstrated by Ki-67 staining was high.. AT/RT is not a particularly uncommon malignancy in childhood. The histologic hallmark is the presence of rhabdoid cells with cytoplasmic inclusions. The tumor cells are positive for cytokeratin, epithelial membrane antigen and vimentin, and negative for INI1. Differential diagnosis includes PNET, medulloblastoma and medullomyoblastoma.

Topics: Brain Neoplasms; Child, Preschool; Diagnosis, Differential; Female; Humans; Infant; Keratins; Male; Medulloblastoma; Mucin-1; Neuroectodermal Tumors, Primitive; Rhabdoid Tumor; Teratoma; Vimentin

We present a case of large cell medulloblastoma with myogenic and melanotic differentiation arising in the cerebellar vermis of a 2-year-old boy and following an aggressive clinical course. Histologic and immunohistochemical features of this tumor include primitive neuronal, rhabdomyoblastic, and pigmented epithelial elements, along with large cell features. Immunohistochemical and molecular data (c-myc gene amplification and the presence of isochromosome 17q) support the contention that this histologically diverse tumor represents a pattern of medulloblastoma with striated muscle and pigmented epithelial differentiation, rather than a teratoma or a cerebellar variant of melanotic neuroectodermal tumor of infancy ('progonoma').

Topics: Antigens, Neoplasm; Cell Differentiation; Cerebellar Neoplasms; Child, Preschool; Chromosomes, Human, Pair 17; Epithelium; Glial Fibrillary Acidic Protein; Humans; Karyotyping; Keratins; Male; Medulloblastoma; Melanoma-Specific Antigens; Muscle Development; Neoplasm Proteins; Neoplasms, Muscle Tissue; Neuroectodermal Tumors, Primitive; Proto-Oncogene Proteins c-myc

Peripheral primitive neuroectodermal tumor (PNET)/Ewing's sarcoma (ES) of the central nervous system is extremely rare and should be differentiated from central PNET and other small blue round cell tumors. We describe a case of a meningeal peripheral PNET/ES of the spinal cord in an 11-year-old boy. Immunohistochemically, the small blue round cell tumor showed expression of epithelial markers and of CD99, thus posing an important differential diagnostic problem with a poorly differentiated synovial sarcoma. Fluorescence in situ hybridization revealed rearrangement of the EWS gene, as seen in peripheral PNET/ES. Peripheral PNET/ES does occur in the central nervous system, but its diagnosis can be extremely difficult on morphologic and immunohistochemical grounds alone. Genetic analysis plays a key role in its distinction from other small blue round cell tumors.

Topics: Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Bone Neoplasms; Child; Diagnosis, Differential; Humans; Keratins; Laminectomy; Male; Meninges; Mucin-1; Neuroectodermal Tumors, Primitive; Sarcoma, Ewing; Sarcoma, Synovial; Spectral Karyotyping; Spinal Cord; Spinal Cord Neoplasms; Vimentin

Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is an extraordinarily rare primary tumor in the kidney and can be mistaken for a variety of other round cell tumors, including blastema-predominant Wilms' tumor (WT). Approximately 90% of ES/PNET have a specific t(11;22), which results in a chimeric EWS-FLI-1 protein. Immunohistochemistry for the carboxy-terminus of FLI-1 is sensitive and highly specific for the diagnosis of ES/PNET. WT-1, the WT-associated tumor suppressor gene, is overexpressed in WT but not in ES/PNET. No study has examined FLI-1 or WT-1 expression in renal ES/PNET. The clinicopathologic features of 11 renal ES/PNET were studied along with immunohistochemistry for cytokeratin, desmin, CD99, FLI-1, and WT-1. WT were also immunostained for CD99 (5 cases), FLI-1 (10 cases), and WT-1 (9 cases). The patients (6 men, 5 women) ranged from 18 to 49 years of age (mean, 34 yr). The mean tumor size was 11.8 +/- 3.8 cm (mean +/- standard deviation). Presenting symptoms included abdominal/flank pain and/or hematuria. Grossly, all tumors showed necrosis and hemorrhage, and 4 had cystic change. Microscopically, all tumors showed vaguely lobular growth, primitive round cells, and variable rosette formation. Epithelial, myogenous, or cartilaginous differentiation was not seen. Immunohistochemical results on the renal ES/PNET were cytokeratin (2/8 focal), desmin (0/9), CD99 (8/8), FLI-1 (5/8), and WT-1 (0/8). In comparison, the WT only rarely expressed CD99 (1/5) and did not express FLI-1 (0/10), but were usually WT-1-positive (7/9). Follow-up on 8 cases (mean, 28 mo; range, 6-64 mo) showed 4 lung and pleural metastases, 1 bone metastasis, liver metastasis, 2 local recurrences, and 5 deaths from disease (median time to death, 16.8 mo). No case had distant metastatic disease at presentation. Adjuvant therapy included chemotherapy (8 cases), radiation (3 cases), and bone marrow transplantation (1 case). Our study affirms a unique proclivity of renal ES/PNET for young adults and that it is a highly aggressive neoplasm, with rapid death in many cases, usually after the development of treatment-resistant lung metastases. These tumors must be distinguished from blastema-predominant WT and other primitive renal tumors that require different therapy. FLI-1 and WT-1 immunohistochemistry may be valuable in this differential diagnosis, given the known immunophenotypic overlap between ES/PNET and blastema-predominant WT with regard to CD99, cytokeratin, and

Topics: 12E7 Antigen; Adult; Aged; Antigens, CD; Cell Adhesion Molecules; Child; Combined Modality Therapy; Desmin; Diagnosis, Differential; DNA-Binding Proteins; Female; Genes, Tumor Suppressor; Humans; Immunohistochemistry; Keratins; Kidney Neoplasms; Male; Middle Aged; Neoplasm Metastasis; Neuroectodermal Tumors, Primitive; Proto-Oncogene Protein c-fli-1; Proto-Oncogene Proteins; Sarcoma, Ewing; Trans-Activators; Wilms Tumor; WT1 Proteins

Topics: Adult; Biomarkers, Tumor; DNA, Neoplasm; Female; Humans; Immunohistochemistry; Keratins; Male; Neoplasm Proteins; Neoplasms, Multiple Primary; Neuroectodermal Tumors, Primitive; Oncogene Proteins, Fusion; Proto-Oncogene Protein c-fli-1; Reverse Transcriptase Polymerase Chain Reaction; RNA-Binding Protein EWS; Sarcoma, Ewing; Transcription Factors

Ewing's sarcoma (ES) and primitive neuroectodermal tumor (PNET) are characterized by the presence of the specific t(11;22)(q24;q12) or variants thereof, producing diagnostic EWS fusion transcripts. Cytokeratin has been reported sporadically to be expressed in some cases of ES/PNET. However, its prevalence has not been assessed systematically in a series of cases with confirmatory molecular or cytogenetic evidence of a diagnostic translocation. We present in detail three index patients in whom strong cytokeratin immunoreactivity was a confounding factor in the diagnosis. To establish further the prevalence of cytokeratin immunoreactivity in a series of well-characterized ES/PNET, we then performed immunohistochemical studies with antibodies CAM5.2 and AE1/AE3 on 50 cases of ES/PNET diagnosed at Memorial Sloan-Kettering Cancer Center in which molecular evidence of a specific ES/PNET-associated translocation were available. Immunoreactivity to cytokeratin was present in 10 cases (20%), in five diffusely and five focally. There was no significant association between cytokeratin expression and the following parameters: patient age, sex, skeletal and extraskeletal primary site, and the type of EWS fusion transcript. Cytokeratin expression, a manifestation of epithelial differentiation, is present in as many as 20% of ES/PNET in either a diffuse or focal pattern.

Topics: Adult; Aged; Child; Female; Humans; Immunohistochemistry; Keratins; Male; Neoplasms, Multiple Primary; Neuroectodermal Tumors, Primitive; Sarcoma, Ewing

Topics: Biomarkers, Tumor; Diagnosis, Differential; Humans; Immunohistochemistry; Keratins; Neuroectodermal Tumors, Primitive; Sarcoma, Ewing

Synovial sarcoma is a relatively common sarcoma in adults, which in its classic bimorphic form infrequently poses a diagnostic problem. Monomorphic spindled variants, as well as the less common poorly differentiated variants, may be confused with other soft-tissue sarcomas; the poorly differentiated variant (PDSS), in particular, may be histologically indistinguishable from other small, blue, round cell tumors, including primitive neuroectodermal tumors (PNETs). Detection of the synovial sarcoma-associated t(X;18) by either cytogenetic or molecular genetic approaches may be necessary to confirm the diagnosis of synovial sarcoma in difficult cases. We evaluated 10 cases of PDSS from eight patients using a panel of antibodies (including those to intermediate filament proteins, nerve-sheath associated markers, and neuronal and neuroectodermal associated markers) in order to better establish the immunophenotype of this tumor and to help distinguish it from the tumors with which it may be confused, particularly PNETs and high-grade malignant peripheral nerve sheath tumors (MPNSTs). Our results showed PDSS to have significant immunophenotypic overlap with both PNETs and MPNSTs. In most instances these three entities may be differentiated by a panel of antibodies that should include those to both low and high molecular weight cytokeratins, epithelial membrane antigen, type IV collagen, CD99, CD56, and S-100 protein. Our results also suggest that synovial sarcoma may be a tumor showing combined neuroectodermal and nerve sheath differentiation--perhaps because of translocation-associated expression of specific proteins--rather than a carcinosarcoma of soft tissues or a tumor of specialized arthrogenous mesenchyme.

Topics: 12E7 Antigen; Adolescent; Adult; Antigens, CD; Biomarkers, Tumor; Cell Adhesion Molecules; Child; Collagen; Diagnosis, Differential; Female; Humans; Immunohistochemistry; Karyotyping; Keratins; Male; Middle Aged; Mucin-1; Nerve Sheath Neoplasms; Neuroectodermal Tumors, Primitive; Neurofilament Proteins; Peripheral Nervous System Neoplasms; Sarcoma, Synovial

Primitive neuroectodermal tumor (PNET), the second most common type of sarcoma in the first two decades of life, rarely presents as an organ-based neoplasm. Rather, it is seen typically in the soft tissues of the chest wall and paraspinal region. We report a case of primary PNET of the kidney in a 17-year-old girl who presented with abdominal pain, hematuria, and an abdominal mass. Nodules and sheets of monotonous-appearing primitive round cells and the formation of rosettes focally were the principal microscopic features. The tumor cells were uniformly immunoreactive for vimentin, cytokeratin, neuron-specific enolase, and 013 (CD99). In addition, the characteristic translocation of PNET and Ewing sarcoma, t(11;22)(q24;q12), was detected by polymerase chain reaction (PCR). Eight previous examples of renal PNET have been reported in the literature in the past 2 years, but only three of these cases have had complete immunohistochemical evaluation with the demonstration of 013 positivity. To our knowledge the present case is the only one to date demonstrating the recurrent translocation t(11;22)(q24;q12) by PCR. Assuming that the previous cases in the literature are bona fide examples of PNET, the kidney may be another site of predilection for this usual soft-tissue neoplasm. We are once again confronted with the dilemma about the nature of the progenitor cell.

Topics: 12E7 Antigen; Adolescent; Antigens, CD; Cell Adhesion Molecules; Combined Modality Therapy; Female; Humans; Keratins; Kidney Neoplasms; Neuroectodermal Tumors, Primitive; Phosphopyruvate Hydratase; Polymerase Chain Reaction; Sarcoma, Ewing; Tomography, X-Ray Computed; Translocation, Genetic; Vimentin

We report an intra-abdominal round cell tumor in a young man which exhibited the light and electron microscopic appearance of a peripheral primitive neuroectodermal tumor (PNET), in addition to the clinical and topographic characteristics, desmoplasia and a complex immunophenotypic profile of the intra-abdominal desmoplastic round cell tumor (DSRCT). Reverse transcription polymerase chain reaction revealed a EWS/FLI-1 fusion transcript as in PNET/Ewing's sarcoma, instead of the EWS/WT1 transcript of DSRCT. The tumor was also strongly positive for the mic2 protein. This is a unique case of a hybrid tumor arising in the peritoneal cavity of a young male. The existence of such a hybrid tumor in this location suggests that DSRCT and PNET may be related and possibly share a common histogenesis.

Topics: Abdominal Neoplasms; Adult; Biomarkers; Blotting, Western; Carcinoma, Small Cell; Desmin; DNA-Binding Proteins; Fatal Outcome; Humans; Immunohistochemistry; Keratins; Male; Microscopy, Electron; Neuroectodermal Tumors, Primitive; Oncogene Proteins, Fusion; Polymerase Chain Reaction; Proto-Oncogene Protein c-fli-1; Proto-Oncogene Proteins; Sarcoma, Ewing; Tomography, X-Ray Computed; Trans-Activators

We present the clinical findings, radiological aspects, operative results, and histopathological features of four typical primitive neuroectodermal tumors (PNET) located in the pontine region in children. All the tumors had an endophytic intra-axial growth pattern. All the children had a short history of severe neurological deficits with involvement of the cranial nerves and pyramidal tract. MRI did not reveal any common feature of malignancy. Compared to our successful experience in operations of intra-axial endophytic brainstem tumors in a total of 32 children, the outcome was poor: all 4 children died within 13 months. We conclude that PNET occurring in the pons is not as rare as was believed, and, compared to PNET in other areas the prognosis is worse.

Topics: Actins; Adolescent; Brain Neoplasms; Child, Preschool; Desmin; Female; Glial Fibrillary Acidic Protein; Humans; Immunohistochemistry; Infant; Keratins; Magnetic Resonance Imaging; Male; Neoplasm Recurrence, Local; Nerve Tissue Proteins; Neuroectodermal Tumors, Primitive; Neurofilament Proteins; Phosphopyruvate Hydratase; Pons; Radiography; Synaptophysin; Vimentin