Extramedullary Intradural Spinal Tumors: A Pictorial Review

Intradural extramedullary tumors. Retrospective cohort study assessing prognostic factors for functional outcome in adult patients

OBJECTIVE

The purpose of this study is to analyze a series of patients with intradural extramedullary tumors (IDEM) and assess factors that may modify or determine the final long term outcome and management.

MATERIALS AND METHODS

Single Center, retrospective study of a series of surgical patients with IDEM lesions from our Institution operated between 2010 and 2021. Patients with less than 6 months of follow up were excluded. Several preoperative demographics, clinical, imaging and surgical features, as well as histopathology, recurrence and adjuvancy were assessed. Patients' final clinical outcome was categorized using the McCormick scale.

RESULTS

A total of 203 patients with a mean follow-up of 30.50 months (range 6-130) were included. 57.64% of the analyzed population was female and the mean age was 50.51 years. The most frequent location of the tumors was dorsal (34.98%) followed by the lumbar region (32.02%). Total resection was achieved in 84.24% of cases, and the most frequent histopathology was Schwannoma (36.45%), followed by Meningioma (30.05%). Pain was the most usual initial symptom (63.05%). In our analysis, functional outcome after surgery was associated with statistical significance with preoperative McCormick grade, tumor type, EOR and postoperative complications such as hematoma and sphincter involvement.

CONCLUSION

The management of these lesions depends on many factors. It is worthy of mention that clinical presentation, EOR, histopathology and postoperative complications have shown significant prognostic value for the final outcome. Early treatment with the intention of achieving GTR when possible, using carefully tailored approaches, should be considered before the onset of significant symptoms.

Characterization and Treatment of Spinal Tumors

The prevalence of spinal tumors is rare in comparison to brain tumors which encompass most central nervous system tumors. Tumors of the spine can be divided into primary and metastatic tumors with the latter being the most common presentation. Primary tumors are subdivided based on their location on the spinal column and in the spinal cord into intramedullary, intradural extramedullary, and primary bone tumors. Back pain is a common presentation in spine cancer patients; however, other radicular pain may be present. Magnetic resonance imaging (MRI) is the imaging modality of choice for intradural extramedullary and intramedullary tumors. Plain radiographs are used in the initial diagnosis of primary bone tumors while Computed tomography (CT) and MRI may often be necessary for further characterization. Complete surgical resection is the treatment of choice for spinal tumors and may be curative for well circumscribed lesions. However, intralesional resection along with adjuvant radiation and chemotherapy can be indicated for patients that would experience increased morbidity from damage to nearby neurological structures caused by resection with wide margins. Even with the current treatment options, the prognosis for aggressive spinal cancer remains poor. Advances in novel treatments including molecular targeting, immunotherapy and stem cell therapy provide the potential for greater control of malignant and metastatic tumors of the spine.

Clinical Reasoning: A 67-Year-Old Woman With Abdominal Pain, Constipation, and Urinary Retention

Meningeal melanocytomas are extremely rare, pigmented tumors of the CNS. They generally carry a favorable prognosis, although recurrence and transformation into the more aggressive malignant melanoma have been reported. We present a case of a patient who reported constipation and abdominal pain around the umbilicus, which progressed into cord compression with lower extremity weakness and gait instability. Spinal MRI revealed a tumor at the level of T11, and she underwent gross total resection of the mass. Pathology demonstrated a meningeal melanocytoma with intermediate features. She received postoperative radiation therapy and had stable disease for 3 years, at which time she developed new weakness and drop metastases. This case represents a rare presentation of a rare disease, in which a spinal cord tumor presented with constipation and abdominal distress. Intradural extramedullary tumors of the thoracic spine are most commonly nerve sheath tumors or meningiomas, but rare entities such as melanocytomas can present in this location; even more rarely, these tumors can have an aggressive course with delayed recurrence.

Large multicystic spinal lesion in a young African migrant: a problem of differential diagnosis

We describe a rare case of large, fully cystic spinal schwannoma in a young adult from The Gambia. The initial clinical suspicion was spinal cystic echinococcosis. He came to our attention reporting progressive walking impairment and neurological symptoms in the lower limbs. An expansive lesion extending from L2 to S1 was shown by imaging (ie, CT scan and MRI). Differential diagnoses included aneurysmal bone cyst and spinal tuberculosis and abscess; the initial suggested diagnosis of spinal cystic echinococcosis was discarded based on contrast enhancement results. The final diagnosis of cystic schwannoma was obtained by histopathology of the excised mass. Cystic spinal lesions are rare and their differential diagnosis is challenging. Awareness of autochthonous and tropical infectious diseases is important, especially in countries experiencing consistent migration flow; however, it must be kept in mind that migrants may also present with ‘non-tropical’ pathologies.

Tarlov Cyst Rupture and Intradural Hemorrhage Mimicking Intraspinal Carcinomatosis

Lumbosacral Tarlov cysts (TCs) have rarely been seen to rupture. Here, we report an unusual presentation of a ruptured TC with intraspinal hemorrhage mimicking carcinomatosis. Pathological diagnosis was obtained using percutaneous biopsy. A conservative approach was utilized and an excellent outcome was achieved. Thus, in cases such as this, a ruptured hemorrhagic TC should be on the differential diagnosis to drive appropriate clinical management decisions.

Clinical characteristics and long-term outcomes for patients who undergo cytoreductive surgery for thoracic meningiomas: a retrospective analysis

OBJECTIVE

Primary spinal meningiomas represent a rare indolent neoplasm usually situated in the intradural-extramedullary compartment. They have a predilection for afflicting the thoracic spine and most frequently present with sensory and/or motor symptoms. Resection is the first-line treatment for symptomatic tumors, whereas other clinical factors will determine the need for adjuvant therapy. In this study, the authors aimed to elucidate clinical presentation, functional outcomes, and long-term outcomes in this population in order to better equip clinicians with the tools to counsel their patients.

METHODS

This is a retrospective analysis of patients treated at the authors' institution between 1998 and 2018. All patients with thoracic meningiomas who underwent resection and completed at least one follow-up appointment were included. Multiple preoperative clinical variables, hospitalization details, and long-term outcomes were collected for the cohort.

RESULTS

Forty-six patients who underwent resection for thoracic meningiomas were included. The average age of the cohort was 59 years, and the median follow-up was 53 months. Persistent sensory and motor symptoms were present in 29 patients (63%). Fifteen lesions were ventrally positioned. There were 43 WHO grade I tumors, 2 WHO grade II tumors, and 1 WHO grade III tumor; the grade III tumor was the only case of recurrence. The median length of hospitalization was 4 days. Seventeen patients (37%) were discharged to rehabilitation facilities. Thirty patients (65.2%) experienced resolution or improvement of symptoms, and there were no deaths within 30 days of surgery. Only 1 patient developed painful kyphosis and was managed medically. Ventral tumor position, new postoperative deficits, and length of stay did not correlate with disposition to a facility. Age, ventral position, blood loss, and increasing WHO grade did not correlate with length of stay.

CONCLUSIONS

Outcomes are overall favorable for patients who undergo resection of thoracic meningiomas. Symptomatic patients often experience improvement, and patients generally do not require significant future operations. Tumors located ventrally, while anatomically challenging, do not necessarily herald a significantly worse prognosis or limit the extent of resection.

Intradural, extramedullary hemangioblastoma at the level of the conus medullaris: illustrative case

BACKGROUND

Hemangioblastomas are rare, slow-growing, and highly vascularized tumors that typically occur in the cerebellum and spinal cord. The cervical and thoracic regions are the most common spinal sites, and the tumors are usually intramedullary.

OBSERVATIONS

The authors report the case of a man whose chest computed tomography performed for managing coronavirus disease 2019 incidentally revealed an enhancing area in the spinal canal at T12–L1. The patient reported low back pain as well as leg numbness and tingling. Magnetic resonance imaging of the lumbar region with and without gadolinium contrast demonstrated an intradural, extramedullary lesion with displacement of the conus medullaris. The differential diagnosis included a schwannoma and myxopapillary ependymoma. Bilateral T12–L1 laminectomies were performed with resection of the mass. The general pathologist rendered the frozen section diagnosis of a spindle cell neoplasm, suggesting the differential diagnosis of schwannoma or myxopapillary ependymoma. Immunohistochemistry was positive for inhibin, GFAP, reticulin, CD31, SOX-10, S100, and EMA. A World Health Organization grade 1 hemangioblastoma was confirmed.

LESSONS

Spinal surgeons should be cognizant of the presenting symptoms and differential diagnosis of hemangioblastomas at the level of the conus medullaris, especially when the tumor is diagnosed incidentally. Additional investigations should be performed to determine whether von Hippel-Lindau syndrome is associated with the hemangioblastoma, as this combination portends a different clinical presentation, multiple tumor locations, and tumor recurrence following resection.

Single-Staged Management of Pediatric Neuropathic Scoliosis with Intradural-Extramedullary Schwannoma and Improvement in Intraoperative Neuromonitoring: A Case Report

CASE

A 16-year-old girl with lumbar prominence presented to our outpatient clinic complaining of sporadic back pain without paresthesia. Radiographic investigation revealed a 68° left thoracolumbar curve with the apex at L1. Preoperative magnetic resonance imaging identified a mass at T10-11, subsequently confirmed by pathology as a schwannoma. She was treated surgically with resection and posterior spinal fusion in a single-staged procedure under neuromonitoring guidance. Intraoperative improvement in motor evoked potentials after resection informed the decision to perform simultaneous deformity correction.

CONCLUSION

We discuss the unusual coincidence of a schwannoma with scoliosis and our management algorithm based on operative changes in neuromonitoring.

Functional Outcomes and Temporal Profile of Recovery in Patients with Intradural Extramedullary Spinal Cord Tumors with Poor Nurick Grade

BACKGROUND

Patients with spinal intradural extramedullary (IDEM) tumors usually have a good functional outcome after tumor excision. However, the literature is sparse on the functional outcome in patients with poor Nurick grade (NG 4 and 5).

METHODS

A retrospective review of 81 patients with IDEM tumors presenting with a poor NG was performed to determine postoperative functional outcome and the temporal pattern of recovery. The following risk factors were analyzed: preoperative NG, duration of symptoms, tumor location, peritumoral edema, presence of syrinx, and tumor type.

RESULTS

Neurologic function started recovering soon after surgery, with >80% of the patients improving by ≥1 grade at the end of 1 week after surgery. Of the 66 patients available for follow-up of >6 months after surgery, 63 (95.5%) improved to NG 0-2 and 51 (77.2%) became asymptomatic (NG 0 or 1). Three patients had a poor functional outcome on follow-up of >31 months; 2 had improved from NG 5 to NG 4, whereas 1 patient continued to be in NG 4. Factors associated with a poor outcome were an upper thoracic location (P = 0.025) and presence of a syrinx (P = 0.004). None of the patients had bladder dysfunction at follow-up of >6 months.

CONCLUSIONS

After excision of spinal IDEM tumors, in patients who present with a poor neurologic function (NG 4 and 5), good functional outcome (NG 0-2) can be expected in >95% of patients. No recovery can be anticipated beyond 1 year after surgery.

Initial Report of an Intradural Extramedullary Metastasis of a Pancreatic Neuroendocrine Tumor to the Cervical Spine: A Case Report and Review of the Literature

BACKGROUND

Pancreatic neuroendocrine tumors (pNETs) are known to frequently metastasize to the liver and lymphatics; however, metastasis to the spine is exceedingly rare. We report the first case of an intradural, extramedullary pNET metastasis to the upper cervical spine.

CASE DESCRIPTION

A 75-year-old Hispanic male patient with history of stage IV pNET with metastasis to the liver and lymph nodes and new-onset lymphadenopathy seen on CT of the chest was found on positron emission tomography scan to have a lesion in the cervical spine. The patient was neurologically intact on physical examination, yet given the patient's medical history, magnetic resonance imaging of the cervical spine was performed, revealing a right-sided intradural, extramedullary mass at the C1-C2 level with associated mass effect on the spinal cord, likely representing a schwannoma. Due to the tumor size, mass effect, and the need for definitive tissue diagnosis, a partial C1-C2 laminectomy with intradural resection of the tumor was performed. The histology was consistent with the patient's known pNET.

CONCLUSIONS

As treatment for pNETs has evolved, there has been a surge in unique presentations of systemic well-differentiated pNETs being reported. It is vital that patients diagnosed with pNET be monitored for metastases, and when discovered, treated promptly.

Differences and characteristics of symptoms by tumor location, size, and degree of spinal cord compression: a retrospective study on 53 surgically treated, symptomatic spinal meningiomas

OBJECTIVE

The differences in symptoms of spinal meningiomas have rarely been discussed from the perspective of tumor characteristics. The main purpose of this paper was to define the differences, if any, in symptoms in patients with spinal meningiomas with respect to tumor size, location, and degree of spinal cord compression. The authors also sought the threshold of spinal cord compression that causes motor weakness.

METHODS

The authors conducted a retrospective study of 53 cases of spinal meningiomas that were surgically treated from 2013 to 2018. Symptoms related to the tumor were classified as motor weakness, sensory disturbance, pain, and bowel/bladder dysfunction. Based on MR images, tumor location was classified by spinal level and by its attachment to the dura mater. Tumor dimensions were also measured. Occupation ratios of the tumors to the spinal canal and degree of spinal cord flattening were sought from the axial MR images that showed the highest degree of spinal cord compression.

RESULTS

Motor weakness and sensory disturbance were significantly more common in thoracic spine meningiomas than in cervical spine meningiomas (p < 0.001 and p = 0.013, respectively), while pain was more common in meningiomas at the craniovertebral junction (p < 0.001). The attachment, height, width, depth, and volume of the tumor showed no significant difference irrespective of the presence or absence of each symptom. In cases of motor weakness and sensory disturbance, occupation ratios and spinal cord flattening ratios were significantly larger. However, these ratios were significantly smaller in the presence of pain. Multivariate logistic regression analysis revealed that occupation ratio independently contributed to motor weakness (OR 1.14, p = 0.035) and pain (OR 0.925, p = 0.034). Receiver operating characteristic curve analysis suggested that occupation ratio with a value of 63.678% is the threshold for the tumor to cause motor weakness.

CONCLUSIONS

The study showed the difference in clinical presentation of spinal meningiomas by spinal level, occupation ratio, and spinal cord flattening ratio. An occupation ratio of approximately 64% could be utilized as the threshold value of tumor growth to cause motor weakness. Tumor growth in the cervical spine might cause pain symptoms before causing motor weakness. The relationship between the tumor and its symptomatology should be discussed with respect to tumor size relative to the surrounding spinal canal.

Physiotherapeutic management of a patient with spinal Schwannoma: A case report

INTRODUCTION

Tumors are generally considered as red flags to manual therapy. The purpose of this report is to describe the clinical course of a patient diagnosed with spinal Schwannoma at L2-L3 level, who was referred to physiotherapy (PT) for the treatment of low back pain radiating to the left lower limb.

CASE DESCRIPTION

A 30-year old man previously diagnosed with L2-L3 Schwannoma was referred for physiotherapy for the treatment of radiating pain. The patient had not responded favorably to symptomatic management. As the patient's history and physical examination were consistent with a mechanical dysfunction, it was decided to manage the patient along similar lines. The patient was treated with McKenzie extension and central postero-anterior mobilization over T4-T6 vertebrae. This intervention was followed up with strengthening and aerobic exercises.

RESULTS

The outcomes were measured by the numerical rating scale (NRS), Oswestry Disability Index (ODI) and the Global rate of Change (GRC) scale. The patient responded well to McKenzie extension exercises and Thoracic mobilization. The NRS (7 at rest; 10 on activity) at the time of referral reduced to (2 on activity) at the time of discharge. The outcomes were maintained after 7 months.

CONCLUSION

This case suggests that there is a need to undertake a detailed musculoskeletal examination and mobilization may be safely performed in patients diagnosed with spinal schwannomas. An individualized tailored approach may be beneficial in these patients.

Retrospective Study on Accuracy of Intraoperative Frozen Section Biopsy in Spinal Tumors

OBJECTIVE

Histologic types and grades are critical in the diagnosis and treatment of spinal tumors. Intraoperative frozen section is a fast and easy method in confirming pathologic diagnosis during the operation. This study was undertaken to reveal the accuracy of intraoperative frozen section biopsy in order to make proper treatment plans.

METHODS

This retrospective study concerned patients who underwent spinal tumor surgeries from 1 January, 2012 to 31 December, 2016. Frozen section biopsy and permanent biopsy were compared, and cases that had differences were counted.

RESULTS

Thirty-seven cases out of 324 patients had discrepancies (11.4%). In discrepant cases 11 cases were ependymoma (29.7%) and 6 cases were schwannoma (16.2%). Among 34 patients who were finally diagnosed with an ependymoma, 11 cases had discrepancies, which was the highest mismatch rate among tumor final pathologic types. By frozen biopsy, astrocytoma (n = 5) and ependymoma (n = 5) turned out to be the most discrepant pathologic types and 16 frozen section biopsy cases were "null." Frozen biopsy astrocytoma (n = 5) mostly turned out to be ependymoma in 4 cases.

CONCLUSIONS

Pathologic findings from frozen biopsy for spinal cord tumors could not be corresponded to final diagnosis, especially when the results of frozen biopsy were ependymoma or astrocytoma. Therefore careful decision making for treatment plans is required.

Serious chronic disease of the cervical spine and trauma in a young female from the middle ages (Czech Republic)

The skeletal remains of the young female (20-24 years) from Grave JP/106, discovered in the Southern Suburb of the Břeclav - Pohansko Stronghold (Early Middle Ages, 9th century-beginning of the 10^th century, present day Czech Republic) display several noteworthy pathologies. The first is deformation of the mandible, which was most probably caused by a fracture of the ramus in combination with a subcondylar fracture. The spine of this young woman also exhibits a probable traumatic injury of the cervical spine in combination with a slowly growing structure situated inside the spinal canal, which caused deformation centered upon C7. The cervical and thoracic spine together with internal surfaces of several ribs exhibit infectious changes of advanced stage, in all likelihood of tuberculous origin, but osteomyelitis cannot be excluded. Histological analysis of the new bone formation in the ribs confirmed infectious origin, as does Micro CT of C5 and C6. Analyses conducted by two different departments with different methods (PCR amplification of 123 bp long section from IS6110 and Next Generation shotgun sequencing) failed to identify DNA of Mycobacterium tuberculosis from the first rib.

Meningioma in cervical spinal cord segment 6 of a dog – a case report

Meningiomas in dogs occur more commonly in the brain than in the cranial spinal cord. Intramedullary spinal cord tumours in dogs are described infrequently and present a diagnostic and therapeutic challenge. A nine-year-old Beagle dog was referred because of tetraparesis of a 20-day duration. The neurological signs were suggestive of a selective lesion involving the cervical spinal cord. Sagittal T2-weighted magnetic resonance imaging of the cervical vertebral column revealed a ventral, well-circumscribed mass within the vertebral canal at the level of cervical segment 6 (C6). A primary neoplasia was considered as probable differential diagnosis. The mass was removed by cervical laminectomy, durotomy and gentle dissections. On the basis of histological and immunohistochemical findings, a diagnosis of transitional meningioma (grade I) was made. Treatment of the meningioma with surgery resulted in a complete recovery, the dog was able to walk 21 days after surgery and had normal walk two months after presentation. Clinicopathologic and treatment data of cranial intraspinal meningiomas have been reported sporadically, but a segment 6 location was not thoroughly described before.

A giant spinal schwannoma mimicking a renal mass: A case report

Spinal schwannomas arise from the cells covering the nerves within the spinal canal. In most cases, they remain confined within the intradural extramedullary space, but occasionally they extend into the extradural space resembling abdominal masses.

We present a case of very large spinal schwannoma mimicking a renal mass at ultrasound exam. Using contrast-enhanced computed tomography and magnetic resonance imaging we were able to detect and characterize the lesion and consequently assign a preoperative diagnosis later confirmed by the histopathology report.

In this paper, we review computed tomography and magnetic resonance imaging features of spinal schwannomas and attempt a summary of possible differential diagnoses.

ALK-rearranged lung cancer with intradural extramedullary spinal cord metastases responding to ceritinib treatment: A case report

Intradural extramedullary spinal cord metastases in lung cancer are rarely reported, but are a disastrous event because of severe clinical symptoms and poor prognosis. Herein, we report a case of a lung cancer patient with ALK rearrangement who experienced brain, leptomeningeal, and intradural extramedullary spinal cord metastases after developing resistance to crizotinib. After ceritinib therapy, his clinical symptoms improved and magnetic resonance imaging revealed that the intradural extramedullary lesions had reduced.

Excision of a centrally based ventral intradural extramedullary tumor of the cervical spine through a direct posterior approach

Introduction

Intradural extramedullary (IDEM) tumors of the cervical spine are removed through an assortment of surgical approaches including: dorsolateral, ventrolateral, and anterior or transoral. Historically, midline ventral IDEM tumors are ostensibly thought to be unfavorable candidates for removal through a direct posterior approach. A case report of a patient with a ventrally based centrally located meningioma in the upper cervical spine (C2/C3) that was removed with direct posterior approach is described.

Case presentation

A 51-year-old male presented with cervicalgia and radiating scapular pain following a remote motor vehicle collision. A ventrally located meningioma in relation to the C2 body was noted on MRI. Management of this patient included obtaining adequate exposure through a posterior approach, complete tumor excision, and maintenance of cervical spine stability. Cervical stability was maintained following total unilateral facetectomy and application of instrumentation from C1-C3.

Discussion

Subsequent to tumor removal, the patient had complete resolution of his cervicalgia, headaches, and scapular pain by his two month follow-up appointment. Although adhesions can make total resection difficult, a posterior approach can grant adequate access to midline ventral meningiomas. Cervical spine stability, tumor location, infection risk, and surgeon familiarity with the approach should all be weighed in decision-making.

Thoracic Intradural-Extramedullary Epidermoid Tumor: The Relevance for Resection of Classic Subarachnoid Space Microsurgical Anatomy in Modern Spinal Surgery. Technical Note and Review of the Literature

BACKGROUND

Intradural epidermoid tumors of the spinal cord are commonly associated with spinal cord dysraphism or invasive procedures. We report the particular relationships between spinal subarachnoid compartments and thoracic intradural-extramedullary epidermoid tumor, highlighting the relevant anatomic changes that may influence microsurgery.

METHODS

A 40-year-old woman from compressive myelopathy owing to a thoracic epidermoid tumor extending from T3 to T4 and not associated with spina bifida, trauma, previous surgery, or lumbar spinal puncture underwent microsurgical excision. Accurate tumor membrane dissection, respecting spinal arachnoidal compartments, was performed. Reposition of a laminoplasty plateau helped in restoring thoracic spine anatomic integrity.

RESULTS

Safe gross total tumor resection was achieved. Complete neurologic recovery as well as absence of recurrent tumor was documented at 4-year follow-up. A literature review revealed only 2 other cases of "isolated" thoracic spine epidermoid tumor. However, description of the relationship between tumor membranes and spinal subarachnoid compartments was not available in either case.

CONCLUSIONS

A thorough knowledge of spinal subarachnoid space anatomy is helpful to distinguish between tumor membranes and arachnoidal planes and to achieve a safe and complete resection to avoid recurrences.

[Clinical Features of Intradural Extramedullary Spinal Cord Metastases in Primary Lung Cancer]

背景与目的

肺癌硬膜下脊髓外转移罕见, 可导致严重的神经损害, 本研究旨在阐明其临床特征。

方法

2013年5月-2016年5月, 北京协和医院8例确诊硬膜下脊髓外转移肺癌患者纳入该研究, 系统回顾分析临床资料。

结果

7例非小细胞肺癌及1例小细胞肺癌合并硬膜下脊髓外转移。马尾综合征是最常见的临床表现。行腰椎穿刺的5例(100%)患者脑脊液找到肿瘤细胞。脊髓增强核磁(magnetic resonance imaging, MRI)发现, 3例软脊膜弥漫线样增强, 4例硬膜下脊髓外多发结节, 1例具有上述两种表现。4例接受靶向治疗和/或放疗患者神经系统症状改善或稳定。中位生存时间是5.8个月。

结论

硬膜下脊髓外转移需依靠神经系统症状及增强MRI影像学检查诊断。靶向治疗和/或放疗可能有效。

Totally cystic intradural schwannoma in thoracic region

Spinal schwannomas are benign intradural extramedullary tumors arising from spinal nerve root sheath. They are usually solid or heterogeneously solid. Totally cystic schwannomas are rare entities. Herein, we report a 60-year-old male presenting with backache radiating along the chest wall and weakness of both lower limbs. He had spastic paraparesis. Magnetic resonance imaging revealed a cystic mass in the thoracic region. At operation, the cystic mass was seen to be attached to D4 dorsal rootlets. It was excised in toto and histopathology confirmed it to be a schwannoma. The relevant literature is reviewed.

Spinal perimedullary vein enlargement sign: an added value for the differentiation between intradural-extramedullary and intramedullary tumors on magnetic resonance imaging

INTRODUCTION

The purpose of this study was to determine the added value of the perimedullary spinal vein enlargement sign on magnetic resonance imaging (MRI) in distinguishing intradural-extramedullary tumors (IDEMTs) from intramedullary spinal tumors (IMTs).

METHODS

Two hundred and eight consecutive spinal intradural tumors with histopathologic confirmation (21 IMTs, 187 IDEMTs) were enrolled. Two readers blinded to the final pathological diagnosis and clinical data independently assessed the venous enlargement sign to determine the agreement between them and jointly distinguished IDEMTs from IMTs according to the common MRI findings. Sensitivity, specificity, and accuracy for the diagnosis of IDEMTs were calculated for the common MRI findings, vein enlargement sign, and a combination of both.

RESULTS

Intraobserver agreement and interobserver agreement for both readers was excellent. The sensitivity, specificity, and accuracy of common MRI findings for differentiating IDEMTs from IMTs were 83.4, 95.2, and 89.3 %, respectively. Thirty-one IDEMTs were mistakenly diagnosed as IMTs, in which seven were cases with vein enlargement signs. By applying the vein enlargement sign to the common MRI findings, the specificity remained at 95.2 %, while the sensitivity improved to 89.3 % and the accuracy increased to 92.3 %.

CONCLUSION

The spinal perimedullary vein enlargement sign is useful in assessing intradural tumors and to differentiate IDEMTs from IMTs.

Thoracic exophytic ependymoma masquerading as a benign extra-axial tumor

Spinal tumors are conventionally differentiated based on location in relation to the spinal cord. Benign spinal tumors such as schwannomas and meningiomas are typically extra-axial (intradural extramedullary) lesions, whereas more aggressive primary spinal tumors such as ependymomas are typically intramedullary masses. Rarely, ependymomas can have both intramedullary and extramedullary components (typically referred to as exophytic ependymomas). We report a case of a spinal exophytic ependymoma that radiographically masqueraded as a benign intradural extramedullary lesion causing cord compression and neurologic deficit in a 47-year-old man. The diagnosis of exophytic ependymoma was made intra-operatively, with resultant gross total resection of the extramedullary portion and subtotal resection of the intramedullary portion. Histopathological examination confirmed ependymoma with World Health Organization grade II/IV. Pre-operative suspicion of an exophytic ependymoma influences operative planning and clinical management. We review the literature and discuss clinical management strategies for these interesting spinal tumors.

C8-T1 Radiculopathy Due to an Intradural Extramedullary Metastasis of a Pancreatic Neuroendocrine Tumor: Case Report and Review of the Literature

Pancreatic neuroendocrine tumors (pNETs) are usually well-to-moderately differentiated neuroendocrine tumors (NETs) that most often metastasize to the liver and lymph nodes with other locations being uncommon. We present a case of intradural pNET metastasis and conduct a review of the literature. Forty-five cases, including the case presently reported, of spinal cord compression due to well-differentiated NETs were found: carcinoid (80%), pNET (13.3%), and NETs of unknown primary (6.7%). Seventy-eight percent of cases consisted of extradural compressions from vertebral bone metastases, whereas there were only 5 cases of intradural extramedullary spinal cord compression. Most cases were managed with surgery and/or radiotherapy with a good clinical outcome in the majority. We report the first case of a pNET intradural extramedullary metastasis and conduct the largest review to date of an infrequent complication of well-differentiated NETs such as malignant spinal cord compression. Aggressive local treatment is warranted in most cases because it usually achieves neurologic improvement and symptomatic relief in patients who may still have a long life expectancy.

Neuroimaging of spine tumors

Intramedullary, intradural/extramedullary, and extradural spine tumors comprise a wide range of neoplasms with an even wider range of clinical symptoms and prognostic features. Magnetic resonance imaging (MRI), commonly used to evaluate the spine in patients presenting with pain, can further characterize lesions that may be encountered on other imaging studies, such as bone scintigraphy or computed tomography (CT). The advantage of the MRI is its multiplane capabilities, superior contrast agent resolution, and flexible protocols that play an important role in assessing tumor location, extent in directing biopsy, in planning proper therapy, and in evaluating therapeutic results. A multimodality approach can be used to fully characterize the lesion and the combination of information obtained from the different modalities usually narrows the diagnostic possibilities significantly. The diagnosis of spinal tumors is based on patient age, topographic features of the tumor, and lesion pattern, as seen at CT and MRI. The shift to high-end imaging incorporating diffusion-weighted imaging, diffusion tensor imaging, magnetic resonance spectroscopy, whole-body short tau inversion recovery, positron emission tomography, intraoperative and high-field MRI as part of the mainstream clinical imaging protocol has provided neurologists, neuro-oncologists, and neurosurgeons a window of opportunity to assess the biologic behavior of spine neoplasms. This chapter reviews neuroimaging of spine tumors, primary and secondary, discussing routine and newer modalities that can reduce the significant morbidity associated with these neoplasms.

Complication avoidance in the resection of spinal meningiomas

BACKGROUND

Surgical resection is considered the treatment of choice for spinal meningiomas and can be safe and effective; however, neurologic and surgical complications occur. This article reviews the factors that may predict susceptibility to this postoperative decline and addresses therapeutic choices, adjunctive therapies, and technologic applications that may help avoid complications.

METHODS

A literature search was conducted for articles related to spinal meningiomas addressing surgical treatment, adjuvant treatment, and technologic applications related to management and minimizing of complications.

RESULTS

There were 16 surgical series identified, comprising 1090 patients with median mortality of 1% (range, 0%-4%), nonneurologic surgical morbidity of 4% (range, 0%-24%), and permanent neurologic deterioration of 6% (range, 0%-21%). Common complications were cerebrospinal fluid leaks and fistulas, venous thromboembolic disease, myocardial infarction, and neurologic deterioration with either transient or permanent neurologic deficits. Predictive risk factors of neurologic decline included pathoanatomic features of lesion calcification, anterior dural attachment, infiltrative tumor, and tumoral adherence to the spinal cord and patient-specific factors of preoperative neurologic and advanced age.

CONCLUSIONS

Alongside surgery, selection of more direct approaches and use of adjuvant radiotherapy in patients with higher grade lesions and recurrent disease may lead to improved outcomes. New technologies, including microsurgical technique, intraoperative electrophysiologic monitoring, intraoperative ultrasound, and ultrasonic aspiration, may improve the safety and limit the complications of resection.

Cystic spinal schwannomas: A short series of six cases. Can we predict them preoperatively?

Background:

Spinal schwannomas are benign tumors arising from the spinal nerve root sheaths and are the commonest intradural extramedullary spinal tumors. Though cystic changes in schwannomas are well described, predominantly cystic schwannomas are uncommon lesions and form a different spectrum of conditions as compared with the commonly seen intradural extramedullary solid lesions.

Case Description:

We present a case series of six patients with spinal intradural extramedullary cystic schwannomas. Two patients had uniloculated cystic schwannomas, two patients had multi-loculated cystic lesions with thick walls and intralesional septations, and two patients had giant cystic schwannomas, one of which had an extradural extension. We report two cases in which preoperative radiological dilemma was encountered and discuss the differential diagnoses of this uncommon entity.

Conclusion:

Cystic spinal schwannomas may be confused with other cystic lesions in the spine, differentiating them preoperatively is important and in this regard, contrast-enhanced magnetic resonance imaging plays a vital role. Frozen section histopathology should be used to identify them at surgery. It is important to detect these lesions at surgery, as total excision is possible and almost always results in good long-term neurological outcome.

Totally cystic schwannoma of the lumbar spine

A schwannoma is a benign tumor arising from a schwann cell and occurs mainly in the nerve sheath in the intradural extramedullary region. Schwannomas have been well described as occurring in the lumbar spine, but total cystic degeneration of schwannomas is rarely reported. The authors describe the clinical and radiographic evaluations and treatment of a rare case of an intraextradural totally cystic schwannoma on the lumbar spine.Two patients reported a history of 6 to 12 months of pain accompanied by weakness in the lower extremities. On examination, 1 patient had bilateral lower-extremity muscle strength graded at 4/5, and magnetic resonance imaging revealed a cystic schwannoma (1.5 × 2.0 cm in the sagittal dimension) at L2-L3. The other patient had a right lower-extremity muscle strength graded at 3/5, and magnetic resonance imaging revealed a cystic schwannoma (2.0 × 3.0 cm in the sagittal dimension) at L4-L5. The patients underwent operative treatment, and the tumors were completely removed, as were the filum terminale adhered to the tumor. Pedicle screws were used to maintain stability of the lumbar spine. Gross examination of the tumors showed yellowish-white soft contents. Histologic examination confirmed that they were benign totally cystic schwannomas. Postoperatively, the patients' neurologic symptoms completely resolved.Cystic schwannomas can be diagnosed using preoperative magnetic resonance imaging. The filum terminale cut off the tumor walls did not cause the clinical symptoms in the 2 patients.

Congenital solitary infantile myofibromatosis involving the spinal cord

Infantile myofibromatosis, a rare mesenchymal disorder that develops in early childhood, is classified by the number of lesions that occur: solitary or multicentric. Involvement of the CNS is unusual in either type. Infantile myofibromatosis in the spine is exceptional, and most published cases represent a secondary invasion. Here, the authors report on an 8-month-old girl presenting with weakness below the ankle and an intraspinal mass extending from T-6 to the conus. The patient underwent only partial surgical removal of the lesion, and the pathology was confirmed as infantile myofibromatosis. After the operation, weakness in the lower extremities gradually improved; however, she could not walk at the time of the final follow-up. On follow-up MRI performed 19 months after the operation, the residual lesion remained unchanged with decreased enhancement.

Minimally invasive surgery for benign intradural extramedullary spinal meningiomas: experience of a single institution in a cohort of elderly patients and review of the literature

Meningiomas of the spine are the most common benign intradural extramedullary lesions and account for 25%–46% of all spinal cord tumors in adults. The goal of treatment is complete surgical resection while preserving spinal stability. Usually, these lesions occur in the thoracic region and in middle-aged women. Clinical presentation is usually nonspecific and the symptoms could precede the diagnosis by several months to years, especially in older people, in whom associated age-related diseases can mask the tumor for a long time. We report a series of 30 patients, aged 70 years or more, harboring intradural extramedullary spinal meningiomas. No subjects had major contraindications to surgery. A minimally invasive approach ( hemilaminectomy and preservation of the outer dural layer) was used to remove the tumor, while preserving spinal stability and improving the watertight dural closure. We retrospectively compared the outcomes in these patients with those in a control group subjected to laminectomy or laminotomy with different dural management. In our experience, the minimally invasive approach allows the same chances of complete tumor removal, while providing a better postoperative course than in a control group.

Recurrent 'universal tumour' of the spinal cord

Lipoma is popularly known as the 'universal tumour' because of its ubiquitous presence anywhere in the body. This is the first documented case of recurrent thoracic spinal cord intramedullary lipoma in a 44-year-old man, with a background of spinal dysraphism, which recurred 15 years after initial surgery. He was followed up every 2 years and currently presented with an 8-month history of progressive weakness in his lower limbs. An MRI of the spine confirmed recurrence of lipoma. He underwent redo laminectomy and partial resection and spinal cord decompression with duroplasty. Lipoma, although a low-grade tumour, can cause significant neurological deficits because of its location. Surgical exploration and removal of lipoma is recommended. However, to preserve the functionality of the spinal cord, one may resort to partial resection and aim for spinal cord decompression. The literature on spinal cord lipoma is reviewed and the aetiopathogenesis of this rare occurrence is described.

Meningioma of the conus medullaris mimicking neurofibroma--possibly radiation induced

BACKGROUND CONTEXT

Radiation-induced meningiomas (RIMs) of the brain are the most common RIMs. However, there has been no report in the literature of an RIM of the spine. Conus medullaris is a favorite site for ependymomas, whereas it is an extremely rare location for meningiomas. Dumbbell-shaped configuration is typical for nerve sheath tumors; however, it is very rarely seen in meningiomas.

PURPOSE

To describe imaging findings of a possibly RIM at the level of the conus medullaris mimicking a neurofibroma.

STUDY DESIGN

A 60-year-old male with 6-year history of irradiated urinary bladder cancer presented with paraparesis.

METHODS

Radiography, computed tomography, and magnetic resonance imaging of the thoracolumbar spine were undertaken.

RESULTS

Radiography showed widening of intervertebral foramina at T12-L1 level. Computed tomography and magnetic resonance imaging disclosed a lobulated intradural mass at the level of the conus medullaris causing widening and scalloping of adjacent bony structures, with dumbbell-shaped configuration. Surgical biopsy of the mass was consistent with fibroblastic meningioma.

CONCLUSIONS

The reported tumor might have developed secondary to irradiation for urinary bladder cancer because meningiomas are the most common radiation-induced central nervous system tumors. Although location at the level of the conus medullaris is atypical for meningioma, and dumbbell-shaped configuration is rather characteristic for neurogenic tumors, they should not exclude a diagnosis of meningioma.

[Spinal tumors]

Spinal tumors can be intramedullary, intradural (within the meninges), or extradural (between the meninges and the bones), or they may extend secondary to the spine from other locations. Vertebral hemangioma represents the most common benign tumor of the spine. Metastases, lymphoma, and multiple myeloma are the most frequent malignant spinal tumors. Primary osseous tumors of the spine, in contrast, are rare conditions but may demonstrate typical imaging findings. For the differential diagnosis, the patient's age, the topographic localization of the mass, and morphologic features of the lesion as depicted by computed tomography and magnetic resonance imaging play important roles.

Intradural Extramedullary Arachnoid Cyst Presenting as Arteriovenous Malformation in the Thoracic Spinal Cord

We report the case of a 57-year-old man who was admitted on the basis of worsening paraplegia and incontinence. This patient had developed similar neurologic symptoms 15 previously but fully recovered after conservative medical therapy with corticosteroids. At that point, he was diagnosed with a thoracic spinal arteriovenous malformation (AVM); yet, no focal spinal lesion was identified. During this second presentation, the patient was initially worked up at an outside institution, where MR imaging revealed serpiginous flow voids along with anterior displacement or atrophy of the cord at the T5-T6 level. Edema of the mid and lower thoracic cord was also noted. While under our care, spinal arteriography and CT angiography failed to conclusively detect an underlying AVM. The patient underwent a second MR study, which showed no major interval change in the pathology. Subsequently, CT myelography of the thoracic spine demonstrated a large intradural extramedullary arachnoid cyst (or arachnoid adhesions resulting in the formation of an entrapped cystic collection). The flow voids that were seen on MR imaging were attributed to venous congestion and dilation arising from chronic compression by the cyst. Cord edema was also found to be secondary to increased interstitial pressure in the setting of this cord compression superiorly. Since surgery was not indicated for this patient at the time of diagnosis, no surgical or pathohistologic assessment was obtained to further characterize the nature of this cystic collection.