Intramedullary subependymoma occupying the right half of the thoracic spinal cord--case report

Spinal Cord Subependymoma: A Subanalysis of the Neurospinal Society of Japan's Multicenter Study of Intramedullary Spinal Cord Tumors

OBJECTIVE

This study aimed to analyze the clinical characteristics, treatment strategies, and surgical outcomes of subependymoma patients from the 2022 Neurospinal Society of Japan multicenter intramedullary spinal cord tumor study.

METHODS

Twenty-six patients with spinal cord subependymoma who were included in the index study of 1,033 patients were retrospectively analyzed.

RESULTS

Mean patient age was 49.4 years. Seventeen patients were men and 9 were women. Sensory disturbance was reported in 22 patients and motor weakness in 18. Median duration of symptoms was 24 months. The tumor was eccentrically located in 19 patients (73.1%) and unilateral in 17 (65.4%). Gross total resection was achieved in 6 patients (23.1%). The same rate for ependymoma patients in the index study was significantly higher (74.8%). Median follow-up was 40.5 months (interquartile range, 18-68 months). In 2 patients who underwent only partial resection, reoperation was required owing to progression 68 and 90 months after surgery, respectively. No recurrence occurred in patients who underwent gross total resection. Five patients experienced neurological worsening after surgery.

CONCLUSION

Although spinal cord subependymoma can be difficult to distinguish from other intramedullary spinal cord lesions before surgery, it is characterized by an indolent clinical course and eccentric location. Surgical treatment should prioritize functional preservation because the prognosis is good even after subtotal resection.

Subependymoma involving multiple spinal cord levels: A clinicopathological case series with chromosomal microarray analysis

Subependymomas of the spinal cord are rare, do not often involve multiple levels, and very rarely recur. Here, we present a series of spinal cord subependymomas with a detailed description of the clinical, radiological and pathological features, and characterization by chromosomal microarray analysis. Briefly, the four patients included two men and two women, between the ages of 22 and 48 years. The most common presenting symptoms were neck and arm pain with upper extremity weakness. By imaging, the tumors were found to involve multiple spinal levels, including cervical/ cervico-thoracic (three patients) and thoracic (one patient), were all eccentric, and had minimal to no post-contrast enhancement. Two patients underwent gross total resection, one had a sub-total resection, and one underwent biopsy alone with a decompressive laminectomy. Follow up ranged from 6 months to 22 years. One patient (case 4) had recurrence 15 years following gross total resection and chromosomal microarray analysis revealed deletions on the long arm of chromosome 6. Our limited series suggests that spinal cord subependymomas can rarely recur, even following gross total resection, suggesting a possible role for long-term surveillance for these rare tumors.

Spinal Cord Subependymoma Surgery : A Multi-Institutional Experience

OBJECTIVE

A spinal cord subependymoma is an uncommon, indolent, benign spinal cord tumor. It is radiologically similar to a spinal cord ependymoma, but surgical findings and outcomes differ. Gross total resection of the tumor is not always feasible. The present study was done to determine the clinical, radiological and pathological characteristics of spinal cord subependymomas.

METHODS

We retrospectively reviewed the medical records of ten spinal cord subependymoma patients (M : F=4 : 6; median 38 years; range, 21-77) from four institutions.

RESULTS

The most common symptoms were sensory changes and/or pain in eight patients, followed by motor weakness in six. The median duration of symptoms was 9.5 months. Preoperative radiological diagnosis was ependymoma in seven and astrocytoma in three. The tumors were located eccentrically in six and were not enhanced in six. Gross total resection of the tumor was achieved in five patients, whereas subtotal or partial resection was inevitable in the other five patients due to a poor dissection plane. Adjuvant radiotherapy was performed in two patients. Neurological deterioration occurred in two patients; transient weakness in one after subtotal resection and permanent weakness after gross total resection in the other. Recurrence or regrowth of the tumor was not observed during the median 31.5 months follow-up period (range, 8-89).

CONCLUSION

Spinal cord subependymoma should be considered when the tumor is located eccentrically and is not dissected easily from the spinal cord. Considering the rather indolent nature of spinal cord subependymomas, subtotal removal without the risk of neurological deficit is another option.

Bamboo Leaf Sign as a Sensitive Magnetic Resonance Imaging Finding in Spinal Subependymoma: Case Report and Literature Review

Background and Importance. Subependymoma occurs very rarely in the spinal cord. We report another case of spinal subependymoma along with a review of the literature and discussion of a radiological finding that is useful for preoperative diagnosis of this tumor. Clinical Presentation. A 51-year-old man presented with a 2-year history of progressive muscle weakness in the right lower extremity. Sagittal magnetic resonance imaging (MRI) showed spinal cord expansion at the Th7–12 vertebral level. Surgical resection was performed and the tumor was found to involve predominantly subpial growth. Histological diagnosis was subependymoma, classified as Grade I according to criteria of World Health Organization. We made an important discovery of what seems to be a characteristic appearance for spinal subependymoma on sagittal MRI. Swelling of the spinal cord is extremely steep, providing unusually large fusiform dilatation resembling a bamboo leaf. We have termed this characteristic MRI appearance as the “bamboo leaf sign.” This characteristic was apparent in 76.2% of cases of spinal subependymoma for which MRI findings were reported. Conclusion. The bamboo leaf sign on spinal MRI is useful for differentiating between subependymoma and other intramedullary tumors. Neurosurgeons encountering the bamboo leaf sign on spinal MRI should consider the possibility of subependymoma.

Surgical outcomes in spinal cord subependymomas: an institutional experience

Spinal cord subependymomas are very rare. Most studies on spinal cord subependymomas have been case reports with literature reviews. This study presented a surgical series of 13 patients with histologically proven spinal cord subependymomas. Their clinical data, radiological findings, operative records, and follow-up outcomes were reviewed. There were 5 male and 8 female patients with a mean age of 39.5 years. The mean follow-up period was 67.8 months. Four tumors were located in the cervical spine, 5 in the cervicothoracic spine, and 4 in the thoracic spine. Gross total resection (GTR) of the tumor with a well-demarcated dissection plane was achieved in 9 cases, and subtotal resection was achieved in 4 cases. The symptoms present before the surgery were improved in 11 cases at last follow-up and the current status of 2 patients had no change compared to the preoperative presentation at last follow-up. The postoperative follow-up magnetic resonance imaging showed no recurrence in the 9 GTR cases during the mean follow-up period of 70.3 months. No recurrence/regrowth of the residual tumors was observed in the 4 STR cases during the mean follow-up period of 62.0 months. Spinal cord subependymomas are amenable to surgical resection. It is possible to achieve GTR of intramedullary subependymomas that have a well-demarcated dissection plane. When GTR cannot be achieved, STR of the lesion for decompression is advised, and follow-up imaging is needed. A good clinical outcome after GTR or STR can be expected.

Cervical Subependymoma: A rare case report with possible histogenesis

Subependymomas are extremely rare lesions of the spinal cord. Only 33 cases including ours have been reported in the cervical cord. These are typically benign slow growing tumors occurring eccentrically within the cord, producing minimal neurological deficits. The clinical, radiological, and histopathological aspects of this unusual lesion have been reviewed in detail. As the histogenesis of this tumor is much debated, we propose an alternate origin for the same.

Thoracolumbar intramedullary subependymoma with multiple cystic formation: a case report and review

BACKGROUND

An intramedullary subependymoma is rare, particularly in the thoracolumbar region. Moreover, a radiographical obvious cystic formation of subependymoma of spinal cord rarely occurs in comparison to ependymoma.

CASE REPORT

A 57-year-old woman presented with paraparesis. MRI revealed a multinodular and multicystic lesion in the spinal cord that was difficult to diagnose correctly. Intraoperative observation via midline myelotomy revealed a grayish, gelatinous solid mass with an eccentric localization. In addition, DREZtomy on the caudal side of the tumor revealed cystic formation. The cyst was punctured and xanthochromic fluid was collected. Attenuation of motor evoked potential (MEP) resulted in the partial removal of tumor. A pathological examination revealed the mass to be a subependymoma. The patient experienced transient worsening of symptoms, but improved gradually. No adjuvant radiosurgery was administered. Follow-up estimation 30 months after surgery revealed no evidences of regrowth.

CONCLUSIONS

This report presents this rare case, a review of the literature associated with thoracolumbar subependymomas, and a discussion of the clinical and radiographical characteristics.

Characteristics of thoracolumbar intramedullary subependymomas

OBJECT

Thoracolumbar intraspinal subependymomas are very rare intramedullary low-grade tumors. The authors report on the clinical and morphological features of 2 cases of thoracolumbar intraspinal subependymomas and provide midterm follow-up data.

METHODS

The clinical and radiological profiles of 2 patients with progressive spinal cord dysfunction due to thoracolumbar intraspinal subependymomas were retrospectively studied and compared with previously reported cases.

RESULTS

Patients with intraspinal subependymomas initially presented with back pain and long-tract signs. The tumors were hyperintense on T2-weighted MR imaging, isointense on T1-weighted imaging, and noncontrast enhancing. Within 1 of the tumors, a medial septum was present on axial T2-weighted imaging. The tumors were intramedullary but grew exophytically and were amenable to gentle surgical separation from normal neural structures. Therefore, gross-total resection was feasible, and neurological outcome was good. No further adjuvant therapy was conducted. On follow-up (at 58 and 18 months, respectively), no tumor recurrence was observed.

CONCLUSIONS

Symptomatic thoracolumbar intraspinal subependymomas with a distinct appearance on MR imaging are amenable to complete excision with favorable neurological outcome. In this study no tumor recurrence was observed at midterm follow-up in either patient, neither of whom underwent adjuvant therapy.

Part I: Spinal-cord neoplasms—intradural neoplasms

Intradural spinal-cord tumours are an uncommon but important consideration in the differential diagnosis of patients with back pain, radicular pain, sensorimotor deficits, or sphincter dysfunction. Intradural spinal tumours can be divided into intramedullary and extramedullary spinal-cord tumours on the basis of their anatomical relation to the spinal parenchyma. The heterogeneous cell composition of the intradural compartment allows the formation of neoplasms, arising from glial cells, neurons, and cells of spinal vasculature. Additionally, developmental tumours, metastases, and intradural extension of extradural tumours are represented. In this Review, we discuss the published work on intradural spinal-cord tumours in terms of epidemiological, radiographic, and histological characteristics. Surgical and adjuvant treatment strategies are also reviewed.