Primary paediatric epidural sarcomas: molecular exploration of three cases.

BACKGROUND: Primary paediatric epidural sarcomas are extremely rare. Overall, there remains a paucity of knowledge in paediatric epidural sarcomas owing to the infrequent number of cases. The Archer FusionPlex Sarcoma Kit (ArcherDX, Inc) is a next-generation sequencing assay that has been reported to be a useful technique to detect recurrent fusion in sarcomas. We report the molecular exploration of 3 primary paediatric epidural sarcomas-one in the cranium (mesenchymal chondrosarcoma) and 2 in the spine (mesenchymal chondrosarcoma and Ewing sarcoma respectively). CASE PRESENTATION: This is a study approved by the hospital ethics board. Clinico-pathological information from 3 consenting patients with primary epidural sarcomas was collected. These selected tumours are interrogated via Archer FusionPlex Sarcoma Kit (ArcherDX, Inc) for genomic aberrations. Results were validated with RT-PCR and Sanger sequencing. All findings are corroborated and discussed in concordance with current literature. Our findings show 2 variants of the HEY1-NCOA2 gene fusion: HEY1 (exon 4)-NCOA2 (exon 13) and HEY1 (exon 4)-NCOA2 (exon 14), in both mesenchymal chondrosarcoma patients. Next, the Ewing sarcoma tumour is found to have EWSR1 (exon 10)-FLI1 (exon 8) translocation based on NGS. This result is not detected via conventional fluorescence in situ testing. CONCLUSIONS: This is a molecularly-centered study based on 3 unique primary paediatric epidural sarcomas. Our findings to add to the growing body of literature for these exceptionally rare and malignant neoplasms. The authors advocate global collaborative efforts and in-depth studies for targeted therapy to benefit affected children.

A case of epidural glioblastoma metastasis presenting with a cervical myelopathy, torticollis, and L'hermitte's phenomenon.

Extraneural glioblastoma metastases are exceedingly rare, though previously described in the literature. Activating mutations in the BRAF kinase gene (V600E) are present in a minority of glioblastoma patients. Here, we describe a case of systemic metastases of a clonal subpopulation of BRAF V600E mutated glioblastoma in a patient previously treated with surgery, radiation, temozolomide and bevacizumab. The patient presented with a subacute cervical myelopathy during adjuvant treatment. He underwent emergent surgical decompression of an epidural spine metastasis. Analysis of the metastatic tumor demonstrated clonal expansion of a BRAF V600E subpopulation. Though rare, systemic metastasis of glioblastoma should be considered in patients presenting with subacute complaints in line with a mass lesion.

Primary Spinal Epidural CIC-DUX4 Undifferentiated Sarcoma in a Child.

Primitive round- or spindle-cell EWSR1-negative undifferentiated sarcomas harboring CIC-DUX4 gene fusion are the most common form of Ewing-like sarcomas. These tumors primarily occur in peripheral soft tissues, but examples have been described within viscera and the brain. As far as we are aware, CIC-DUX4 positive primary epidural spinal sarcoma has not been reported. Herein, we describe a T5-T6 epidural tumor in a 15-year-old girl in which many neoplastic cells had moderate and focally abundant cytoplasm, including plasmacytoid or rhabdoid cells, rather than the more common Ewing-like morphology described in the majority of such tumors. The diagnosis was confirmed by fluorescent in situ hybridization after the tumor was found to be WT-1 positive, and comprehensive genomic profiling demonstrated breakpoints in exon 20 and exon 1 of the CIC and DUX4 genes, respectively. After treatment with local radiation and systemic chemotherapy, resected recurrent tumor demonstrated more pleomorphic neoplastic cells as well as intracytoplasmic eosinophilic globules and nuclear pseudoinclusions which may reflect therapy-related changes. Unfortunately, there was further progression of tumor including the development of intracranial lesions, and the patient succumbed to her tumor 22 months after the original resection.

Ewing sarcoma of the thoracic epidural space in a young child.

PURPOSE: To report on the clinical course and treatment of Ewing sarcoma of the thoracic epidural space in a 5-year-old girl. METHODS: We present the case of a 5-year-old girl who experienced back pain (day 1); on day 10, the pain had exacerbated and involuntary movements in the lower limbs occurred, and an MRI performed in her local hospital revealed a tumor lesion at the upper thoracic level. RESULTS: On day 13, emergency surgery was performed for partial resection of the tumor. Pathological examination of the resected tumor by immunostaining and gene testing revealed that it was MIC2 positive and an EWS-FLI 1 chimera, respectively, and Ewing sarcoma was diagnosed. The involuntary movements resolved immediately after the surgery. Three weeks after the operation, chemotherapy and radiation therapy were commenced. After 5 months, deep tendon reflexes recovered to normal. MRI showed that the tumor has not recurred at 29 months after surgery. CONCLUSIONS: The majority of epidural patients undergo emergency surgery only after symptom exacerbation, which includes the development of neurological deficits. Thus, preoperative diagnosis of Ewing sarcoma of the epidural space is difficult and diagnosis is frequently made by a post-operative gene test. The resection area is limited to the intralesional margin area because a larger resection is difficult due to the characteristics of the affected region; thus, there is a higher possibility of recurrence and careful follow-up of the case is necessary.

Primary epidural lymphoma. Case report.

A case of follicular center cell lymphoma arising in the spinal dura mater is presented. To the authors' knowledge, this is the first case of primary epidural lymphoma in which immunohistochemical and molecular investigations demonstrated a follicular center cell origin.

Multiple granulocytic sarcomas in acute myeloblastic leukemia with simultaneous occurrence of t(8:21) and trisomy 8.

This report describes a rare case of multiple intracranial, extradural chloromas. A five year old African American male presented with headache, fever, and vomiting. The peripheral blood smear showed myeloblasts with Auer rods. The CTscan of the brain showed three intracranial, epidural lesions as well as soft tissue masses in the retroorbital region and sphenoid sinuses. CTscan of the chest showed two paraspinal epidural thoracic masses. Pathology of the epidural intracranial mass revealed a granulocytic sarcoma. Cytogenetic analysis showed simultaneous occurrence of t(8;21) and trisomy 8. Following induction therapy, he is now in complete remission.

Peripheral primitive neuroectodermal tumor within the spinal epidural space.

A case of an epidural spinal peripheral primitive neuroectodermal tumor (pPNET) in a 13-year-old girl is presented. The tumor was disseminated at the moment of diagnosis, thus only diagnostic oligobiopsy of the epidural mass was performed. Histologically the tumor was composed of small round blue cells. The neoplastic cells expressed MIC2 and features of neural differentiation on immunohistochemical staining (neuron-specific enolase, synaptophysin and NCAM positivity). Fluorescent in situ hybridization (FISH) analysis was performed for the final diagnosis and the translocation t(11;22)(q24;q12) was detected. The present case emphasizes the usefulness of FISH in differential diagnosis of tumors, especially when only routinely fixed material is available.

Melanotic neuroectodermal tumor of infancy: a molecular approach to diagnosis. Case report.

A case of melanotic neuroectodermal tumor of infancy arising from the transverse sinus is presented. The tumor was located on the outer surface of the dura and extended extracranially through the occipitomastoid suture. Two cell populations were observed: pigmented melanocyte-like cells and small neuroblast-like cells. Ultrastructural analysis revealed epithelial tumor cells and melanosomes at various stages. Expression of melanotransferrin messenger RNA transcripts within the tumor tissue was observed using a reverse transcriptase-polymerase chain reaction method in addition to immunohistological studies. The positive expression of melanotransferrin confirmed that this melanotic neuroectodermal tumor was derived from neural crest cells.

Paraparesis secondary to a spinal mass as the presenting feature of erythroleukaemia in a 10-month-old child.

Severe neurological impairment as the first symptom of acute leukaemia is a rather uncommon finding. We report the case of a 10-month-old infant who presented with acute paralysis of the lower extremities due to cord compression by an epidural tumour composed of malignant erythrocyte precursor cells. Diagnosis of erythroleukaemia (EL) was made by needle biopsy of the spinal epidural mass and confirmed by bone marrow aspiration. Antileukaemic treatment in combination with radiotherapy to the epidural tumour led to haematological remission and neurological recovery with disappearance of the mass lesion as demonstrated by MRI. However, haematological relapse occurred with death of the patient 7 months after diagnosis. This is the first reported case of EL presenting with paraparesis due to an epidural tumour. The clinical symptoms, results of cytogenetic and immunological studies and the clinical course are described.