Intramedullary Ewing's Sarcoma
Intramedullary Ewing's Sarcoma (either primary or secondary) is rare, and the ideal management remains inconclusive.
Case reports
Mousavi et al. reported a intramedullary and extramedullary metastatic ES in a single patient. A 46-year-old woman was referred to the outpatient clinic from the oncology clinic with progressive paraparesis and paresthesia for 1 week prior to presentation. She had developed left clavicular ES 2 years earlier for which surgery and chemoradiotherapy had been performed. At the present evaluation, she was diagnosed with intramedullary thoracic and lumbar extradural masses. Thoracic surgery was performed, and a biopsy of the lesion was obtained. The diagnosis of ES was confirmed histopathologically, and she underwent adjuvant chemotherapy. Her neurological status did not improve after surgery, and she underwent rehabilitation and physical therapy. The lumbar lesion was resolved with chemotherapy. Metastasis of ES to the spinal cord, especially intramedullary lesions, is extremely rare, and there is no standard management guideline. However, surgical decompression and adjuvant chemotherapy are the main treatments in these cases 1).
A 39-year-old man with a history of surgery and chemoradiotherapy for thoracic Ewing sarcoma ten years ago presented with neck pain and incomplete motor paralysis in the right upper extremity, which had suddenly appeared three months before. Cervical magnetic resonance imaging revealed a tear-drop-shaped intramedullary lesion at the C3 level accompanied by diffuse edematous change. Because of the rapid progression of his myelopathy, he underwent surgery for this intramedullary lesion. Intraoperatively, the tumor exhibited an orangish exophytic appearance. The unclearness of the tumor boundary compelled us to perform a partial resection. The histopathology showed the tumor comprised small round atypical cells with immunoreactivity for Nkx2.2 and CD99, diagnosing a metastatic Ewing sarcoma. Postoperatively, although his myelopathy improved transiently and adjuvant chemotherapy radiation was undergone, he died of cranial dissemination of the tumor two months and a half later.
31 cases of primary and only 4 cases of recurrent intramedullary spinal Ewing sarcoma have been reported to date; however, this is the first case of recurrent intramedullary Ewing sarcoma with a 10-year disease-free survival. Sadly, the prognosis of the current case was extremely poor. There is no clear treatment guideline for recurrent intramedullary Ewing sarcoma because of its rarity, and further collection of similar cases would be required 2).
A 23-year-old man presented with weakness in the extremities. Magnetic resonance imaging revealed a large intramedullary tumor spanning C3-C5 with heterogeneous enhancement following gadolinium administration. Histologically, most of the tumors displayed dense myeloid proliferation composed of medium- to slightly small-sized primitive cells. Postoperatively, he received local adjuvant radiation therapy without tumor progression for 10 months. Targeted RNA-sequencing analysis revealed the CIC-DUX4 fusion gene. Methylation array analysis resulted in a diagnosis of “methylation class CNS Ewing sarcoma family tumor with CIC alteration”. Although this tumor lacked characteristic histological features such as lobular structures in association with desmoplastic stroma, relatively uniform nuclei with prominent nucleoli and eosinophilic cytoplasm, which are often found in CIC-rearranged sarcomas of soft tissue, were identified. Recently, many CNS and soft tissue tumors require genetic analysis for precise diagnosis. To consider certain molecular testing, careful histological examination is essential 3).
This case report describes a patient with a rare occurrence of primary spinal intramedullary Ewing's sarcoma (ES) in the cervical and thoracic spine. The older age of disease occurrence, uncommon location in the cervical and thoracic spine, and EWSR1 gene fusion as the basis of diagnosis are unique features of this case. There is no clear protocol for the treatment of primary extraskeletal ES of the spine, with the controversy between evidence for pursuing surgery versus a combination of radiation and chemotherapy. Our patient was treated with temozolomide chemotherapy for recurrent metastatic disease of primary ES of the spine 4)
A 16-year-old girl with progressive weakness of lower extremities, inability to walk, progressive low back pain, bilateral leg pain, paresthesia, and urinary retention. Spinal MRI showed intramedullary abnormal signal focus from T11 to L3 vertebrae with moderate heterogeneous enhancement on T1 weighted sequences. After surgery, the histological examination found a lot of small round-cell tumors with a high nuclear-cytoplasmic ratio, frequent mitoses, and apoptotic nuclei suggesting a diagnosis of Ewing’s sarcoma and confirmed by CD99 reactivity. She had undergone adjuvant chemotherapy and irradiation and was free of symptoms for 02 years. Within this single pure case of intramedullary Ewing’s sarcoma, perhaps the 1st in the English literature, the authors described this extremely rare uncommon localization with a brief review of the literature 5)
Intramedullary Ewing's sarcoma of the spinal cord associated with hydrocephalus 6).
An unusual case of a primary, extraosseous ES arising from the intramedullary spinal cord, in which molecular studies were required for specific diagnosis and therapeutic guidance 7)