Dumbbell-shaped peripheral primitive neuroectodermal tumor of the spine--case report and review of the literature

Primary Ewing sarcoma/peripheral primitive neuroectodermal tumors in the cranial bone and mobile spine: what is the difference?

BACKGROUND

Primary Ewing sarcoma (ES)/peripheral primitive neuroectodermal tumors (pPNETs) are aggressive bone tumors that rarely occur in the axial skeleton, including the cranial bone and mobile spine. The purpose of this study was to investigate whether there were any differences in patient characteristics, treatment strategies, and outcomes between patients with ES/pPNETs of the cranial bone and those with ES/pPNETs of the mobile spine.

METHODS

A retrospective study was performed on 33 patients with ES/pPNETs who had been surgically treated and pathologically confirmed at our institution between 2010 and 2020. Patient characteristics were compared using Fisher exact tests or independent t tests. Survival rates were estimated via Kaplan-Meier survival analysis and compared using log-rank tests.

RESULTS

Thirteen patients had ES/pPNETs of the cranial bone (39.4%), while 20 patients had ES/pPNETs of the mobile spine (60.6%). Patients with ES/pPNETs of the cranial bone had a younger mean age (14.8 vs 22.6 years; p = 0.047) and longer mean disease duration (2.5 vs 1.9 months; p = 0.008) compared with those of patients with ES/pPNETs of the mobile spine. Kaplan-Meier analysis showed that gross total resection (GTR) and radiotherapy resulted in a longer median survival time. The overall survival rates and progression-free survival rates of patients with ES/pPNETs of the cranial bone versus those of the mobile spine were not significantly different (p = 0.386 and p = 0.368, respectively).

CONCLUSIONS

Patients with ES/pPNETs of the cranial bone were younger compared to patients with ES/pPNETs of the mobile spine. There was no significant difference in the prognosis of patients with ES/pPNETs of the cranial bone versus those of the mobile spine. Taken together, our findings suggest that GTR and radiotherapy offer the best prognosis for improved long-term survival.

Spinal Ewing's Sarcoma Presenting as an Epidural Collection: A Rare Presentation of a Rare Entity

Rare entities are difficult to predict. They are considered last rightly, to expedite treatment and alleviate symptoms quickly. Rare presentations of rare diseases form a particularly difficult section of diagnoses that are not only impossible to predict but difficult to recognize, diagnose, and treat. Often the dilemma is to, investigate thoroughly saving time but financially burdening the patient and hospital, or, to investigate in gradual increments taking more time and effort, especially in rare cases where prolonged hospitalization and suffering occurs before the diagnosis is reached. This approach, however, wastes critically important time, which, especially in neurological compression, may often lead to irreversible deficits. This dilemma is admirably demonstrated in this case report of spinal Ewing's sarcoma. A young female presented to us with recurrent high cervical epidural collections presenting as compressive myelopathy. She underwent repeated decompressions, and the collection was misdiagnosed as tuberculosis, which was treated without empirical evidence, leading to significant irreversible disability. Finally, when she came to us, the histopathological assessment was done to reveal the diagnosis. Ewing's sarcomas, and indeed the whole gamut of small-round-cell malignancies, are great imitators. They are known to exist in the skull base mimicking schwannomas, chordomas, germinomas, pituitary adenomas, and even epidermoids and occasionally extend to the vertebral bodies and the cranio-vertebral Junction (CVJ) leading to instability and neurological compression. Here, they mimic vertebral tumors, discitis, infective abscesses, and even myeloma. Predictably, such an entity is diagnosed last, and diagnosed late, leading to bad consequences for the patient. Such was the fate of our patient. The report emphasizes the diagnostic dilemma and presents the need to use protocols for diagnosis and treatment, even in rare cases, to effect the best possible outcomes for patients. The use of a thorough diagnostic and management algorhythm prevents deeper and sinister disease processes from being missed.

Treatment Outcomes and Prognostic Factors of Patients With Primary Spinal Ewing Sarcoma/Peripheral Primitive Neuroectodermal Tumors

Purpose: Primary spinal Ewing sarcoma (ES)/peripheral primitive neuroectodermal tumors (pPNETs) are extremely rare, and the current understanding of these tumors is poor. The authors aimed to illustrate the clinical characteristics of primary spinal ES/pPNETs and to discuss prognostic factors by survival analysis.

Methods: A total of 40 patients who were pathologically diagnosed with primary spinal ES/pPNETs between 2000 and 2018 were enrolled in this study. Progression-free survival (PFS) and overall survival (OS) were estimated by the Kaplan–Meier method to identify potential prognostic factors. Factors of p ≤ 0.1 in the Log-rank tests were subjected to multivariate analysis by Cox regression analysis.

Results: The mean follow-up period was 23.8 (range, 2–93) months, and 24 (60.0%) patients had local recurrence and 11 (27.5%) patients had distant metastasis. The 1-, 2-, and 5-year PFS rates were 57.7, 30.4, and 9.5%, respectively. The 1-, 2-, and 5-year OS rates were 74.8, 50.7, and 12.2%, respectively. The univariate analysis suggested that resection mode, postoperative Frankel score, adjuvant chemotherapy and adjuvant radiotherapy were potential prognostic factors for OS and PFS. However, after these factors were subjected to multivariate analyses, only adjuvant radiotherapy and resection mode remained as independent prognostic factors.

Conclusions: Total en bloc resection can significantly improve PFS for primary spinal ES/pPNETs and adjuvant radiotherapy was a favorable factor for PFS. Total en bloc resection and adjuvant radiotherapy considerably improve OS for patients with primary spinal ES/pPNETs.

Management of Dumbbell and Paraspinal Tumors of the Thoracic Spine Using a Single-stage Posterolateral Approach: Case Series

This study investigated the surgical results of a single-stage posterolateral approach with arc incision, unilateral laminectomy, and costotransversectomy for the management of dumbbell tumors and paraspinal tumors of the thoracic spine. From January 2010 to March 2017, 14 patients with dumbbell tumors or paraspinal tumors of the thoracic spine who underwent resection with single-stage posterolateral approach were followed up and analyzed retrospectively. The operations were performed using a single-stage posterolateral approach with arc incision, unilateral laminectomy, and costotransversectomy without any instrumentation. We reviewed the scores of clinical symptoms and imaging results, including postoperative MRI and reconstructed 3D-CT images. Gross total removal was achieved in 13 patients, and subtotal removal was achieved in 1 case. Histopathology revealed schwannoma in 9 patients, angiolipoma in 1 patient, and paraganglioma and mixed hemangioma in 2 patients each. No significant operative or postoperative complications occurred in any patient. The 14 patients were followed up for 14-68 months (mean 39.4 months). At the final follow-up, no obvious spinal deformity or tumor recurrence was found in any patient except one with paraganglioma. Single-stage posterolateral approach is a good alternative surgical method for removing dumbbell tumors and paraspinal tumors of the thoracic spine without necessitating a subsequent anterior operation.

Long-term outcomes of surgical resection with or without adjuvant therapy for treatment of primary spinal peripheral primitive neuroectodermal tumors

OBJECTIVE

We sought to assess the use of surgical treatment, the effect of postoperative adjuvant therapy, and the prognostic factors for survival of patients with primary spinal peripheral primitive neuroectodermal tumors (pPNETs).

PATIENTS AND METHODS

The clinical data of 24 patients, who had been surgically treated from April 2003 to February 2018 and in whom immunohistochemical staining results had confirmed the diagnosis of primary spinal pPNETs, were retrospectively analyzed. To analyze the factors related to prognosis, the Kaplan-Meier method was used for univariate analysis, the log-rank method was used to test the significance of difference, and multivariate analysis was performed using Cox regression.

RESULTS

The overall 1-year, 2-year, and 5-year survival rates were 73.2%, 48.1%, and 12.0%, respectively. The median survival time (MST) of all patients was 21 months. Univariate analysis showed that the extent of tumor resection, adjuvant radiotherapy, and chemotherapy were the factors influencing patient prognosis after surgery (all P < 0.05); sex, age, tumor location, and preoperative Karnofsky performance scale (KPS) scores were not the influential factors for prognosis of patients after surgery (all P > 0.05). Multivariate analysis showed that gross total resection (GTR) of tumors and adjuvant radiotherapy were independent factors influencing the prognosis of patients with pPNETs (all P < 0.05).

CONCLUSIONS

Primary spinal pPNETs are extremely rare, and they have a poor prognosis. Microsurgical GTR of the tumor is the preferred method of treatment. Radiotherapy plays an important role in improving the prognosis of patients with pPNETs. GTR combined with radiotherapy and chemotherapy may be the best treatment modality.

Recurrent spinal primitive neuroectodermal tumor with brain and bone metastases: A case report

RATIONALE

Primary spinal primitive neuroectodermal tumor (PNET) is relatively rare in all age groups, and the prognosis in most cases of spinal PNETs appears to be poor, with a median patient survival of 1 to 2 years. We present a case with recurrent spinal PNET with brain and bone metastases that was successfully treated by multimodality treatment.

PATIENT CONCERNS

A 14-year-old teenage girl had suffered from progressive left upper back pain with bilateral lower legs weakness and numbness for 1 year. After treatment, left neck mass was noted 3 years later.

DIAGNOSES

Initially, magnetic resonance imaging (MRI) showed neurogenic tumor involving intradural extramedullary space of T5-T10. Pathology report showed PNET (World Health Organization grade IV) featuring lobules of neoplastic cells with round regular nuclei, high nucleus-to-cytoplasm ratio, and fibrillary cytoplasm. At the time of tumor recurrence, chest MRI then showed recurrent tumor at T2-T3 level of the epidural space with right neural foramina invasion. Brain MRI showed extensive bilateral calvarial metastases and leptomeningeal metastases in the right frontoparietal regions. Bone scan showed multiple bone metastases.

INTERVENTIONS

T-spine tumor removal and adjuvant radiotherapy (RT) to T-spine tumor bed were performed in the initial treatment. After clinical tumor recurrence, tumor removal was done again. She then received chemotherapy followed by whole brain irradiation with hippocampal sparing with 35 gray in 20 fractions.

OUTCOMES

After treatment, follow-up images showed that the disease was under control. There was no neurological sequela. She has survived more than 7 years from diagnosis and more than 4 years from recurrence to date.

LESSONS

Multimodality treatments including operation, RT, and chemotherapy should be considered in the initial treatment planning, and salvage chemotherapy was useful in this case.

Clinical presentation and long-term outcome of primary spinal peripheral primitive neuroectodermal tumors

Primary spinal peripheral primitive neuroectodermal tumors (pPNETs) are extremely rare entities that predominantly occur in children and young adults. Few studies have reported more than three cases. There are no current optimum treatment strategies due to the paucity of data. Here, we present 13 patients (nine females and four males) with primary intraspinal pPNETs who were surgically treated from April 2008 to February 2014. Histopathologic findings revealed the expression of CD99 in all cases. Limb weakness was the most common initial symptom (11/13, 85 %). The tumors were located mainly at the cervical level (6/13, 46 %) and in the epidural space (10/13, 77 %). The radiological diagnosis was neurinoma or meningioma in most cases (10/13, 77 %). Gross total resection was achieved in 77 % (10/13) of patients. During a mean follow-up of 25.5 months, local relapse occurred in 8 (61.5 %) patients and distant metastases occurred in 8 (61.5 %) patients. The overall 1-year survival rate was 77 % (10/13), and the overall 2-year survival rate was 54 % (7/13). The 2-year survival rate was 57.1 % in patients with adjuvant chemotherapy and 50 % in those without chemotherapy. Gross total resection and adjuvant radiotherapy with or without chemotherapy demonstrated a longer survival period (1-year survival rate: 100 %; 2-year survival rate: 86 %). Our data showed that primary spinal pPNETs are extremely rare and aggressive tumors with a poor prognosis. Radical resection is advocated. Gross total resection combined with adjuvant radiation may help to significantly improve patient survival period. Chemotherapy may also help to slightly prolong patient life.

Primary spinal primitive neuroectodermal tumour - a case report

Primitive neuroectodermal tumours (PNET) are aggressive childhood malignancies and offer a significant challenge to treatment. A two years old female child presented with weakness both lower limbs. Preoperative MRI of the spine and paravertebral regionIso – hyper intense posterior placed extradural lesion, non contrast enhancing from D11-L2 levels with cord compression D9 to L3 laminectomy done. Granulation tissue found from D11 to L2. with cord compression. The granulation tissue removed in toto. The pathological findings were consistent with PNET. Post operative neurological improvement was minimal. Cranial screening ruled out any intracranialtumour. Hence a diagnosis of primary spinal PNET was made. A review of the literature shows that only 19 cases of primary intraspinal PNETs have been reported to date and the present case extradural in location. Primary intraspinal PNETs are rare tumors and carry a poor prognosis.

Modern surgical techniques for management of soft tissue sarcomas involving the spine: outcomes and complications

Several types of soft tissue sarcomas may locally extend to the spine. The best therapeutic strategy for such lesions strongly depends on the histological diagnosis. In this article the authors provide an up-to-date review of current guidelines regarding the management of soft tissue sarcomas involving the spine. Special attention is given to outcomes and complications of modern surgical series in order to highlight current challenges in the management of such lesions.

Primary spinal extradural Ewing's sarcoma (primitive neuroectodermal tumor): Report of a case and meta-analysis of the reported cases in the literature

Background:

Primary spinal primitive neuroectodermal tumors (PNET) and/or spinal extraskeletal Ewing's sarcoma family tumors (ESET) are rare lesions appearing in the spinal extradural space. One hundred forty-one primary spinal PNETs, including 29 intramedullary lesions, have been reported in the literature. Encountering a case of primary epidural EES/peripheral PNET (pPNET) in sacral level, which is the fifth one occurring at this level in the literature, we have tried to conduct a meta-analysis of the reported cases.

Case Description:

A 44-year-old lady with epidural EES/pPNET is reported here. She was once operated for L5/S1 herniated disc, which did not ameliorate her symptoms. The clinical, imaging, surgical, and histopathologic characteristics of our case are presented and wide search of the literature is also done. All the reports were level 3 or less evidences and most of the series had missing parts. 106 cases of primary intraspinal (extradural/extramedullary-intradural) EES/pPNET and 29 cases of primary intramedullary PNET (CNS-PNET) have been reported in the literature. The most common clinical presentation in both entities was muscle weakness proportionate to the tumor location. Distant metastasis occurred in 38 of 99 (38%) cases of primary intraspinal EES/pPNET, while the rate of metastasis was 48% in patients with PNETs occurring in the intramedullary region (P > 0.05). One-year survival rate of the patients who underwent chemo-radiation after total or subtotal resection was better than those who did not receive chemotherapy or radiotherapy, or did not have total or subtotal resection. However, this difference was not repeated in 2-year survival rate in any of the tumor groups.

Conclusion:

It seems that total or subtotal removal of the tumor and adjuvant chemo- and radiation therapy can improve the outcome in these patients.

Magnetic resonance imaging characteristics of primary intraspinal peripheral primitive neuroectodermal tumour

PURPOSE

The purpose of our study was to describe the salient magnetic resonance imaging (MRI) findings in primary intraspinal peripheral primitive neuroectodermal tumour (PNET).

METHODS

A retrospective review of the clinical and MRI images of 7 pathologically proven cases of intraspinal peripheral PNETs was performed. The various parameters, such as vertebral level of involvement; tumour location, size, focality, and margin; signal intensity of the lesion; the presence of hemorrhage or calcification; any signal voids; assessment of the adjacent cord for cord compression; cord dilatation; the presence of paraspinal tissue mass; or vertebral or other bony changes, were analysed.

RESULTS

All 7 patients had lesions in the thoracolumbar region. Three patients had extradural lesions, 4 had intradural extramedullary lesions, and none had intramedullary lesions. Six lesions were well circumscribed. Only 1 patient had multifocal involvement. All lesions were of hypointense or isointense signal on T1-weighted imaging, whereas all but one were hyperintense on T2-weighted imaging. Lesions enhanced heterogeneously except 1 intradural extramedullary lesion, which enhanced homogeneously. A paraspinal mass was noticed in 2 patients. Vertebral collapse was present in 1 patients.

CONCLUSION

Intraspinal peripheral PNETs are rare spinal tumours. Although imaging characteristics are not specific, a focal circumscribed lesion in a young individual at the intramedullary, extramedullary intradural, or extradural spinal location that shows hypointense and hyperintense signal on T1- and T2-weighted images, respectively, requires PNET to be considered in the differentials.

Intraspinal primitive neuroectodermal tumor in a man with neurofibromatosis type 1: Case report and review of the literature

BACKGROUND

The occurrence of primitive neuroectodermal tumors (PNET) in patients with neurofibromatosis type 1 (NF1) has only been reported in two other cases in English-Language literature. Owing to the rarity of intraspinal PNET and the extremely high gene mutation variability in NF1, there is currently no conclusive evidence to suggest that PNET is associated with NF1. Here, we report a case of intradural PNET in a patient with NF1.

CASE DESCRIPTION

A 27-year-old male underwent a C1-C3 laminectomy for resection of an intramedullary mass. Histopathology and immunohistopathology analysis was performed. Microscopic examination and immunohistochemical staining indicated the mass was a primitive neuroectodermal tumor. Within 1 month after tumor resection, the patient developed leptomeningeal carcinomatosis. The patient was not a candidate for radiation therapy but underwent palliative systemic chemotherapy. He subsequently developed neutropenia and died 3 months after tumor resection.

CONCLUSION

To our knowledge, this is the first reported intraspinal PNET associated with NF1. Genetic analysis of CNS PNETs suggests a possible correlation, but larger case series are needed to support this theory.

Intraspinal Ewing's sarcoma/primitive neuroectodermal tumors

Intraspinal Ewing's sarcoma (ES) and primitive neuroectodermal tumors (PNET) are very rare, and the characteristics and prognoses of the disease remain unclear. We present an illustrative patient with an intradural, extramedullary PNET arising within the cervical spinal canal, with clinical and radiological manifestations of leptomeningeal spread, and review the reports of a further 77 patients with intraspinal ES/PNET. Cox regression analyses showed that tumor location (extradural, intradural) (p=0.002, RR=4.217, 95% confidence interval [CI] 1.668-10.664) and spinal segment location (cervical, thoracic, lumbar, or sacral) (p=0.017, RR=2.040, 95% CI 1.133-3.673) were independent factors in the prognosis of intraspinal ES/PNET. We concluded that a peripheral PNET may originate within the spinal canal and exhibit leptomeningeal spread similar to that seen in central PNET, and that a patient with an intradural ES/PNET high in the spinal canal is more likely to have a poor prognosis.

Primitive neuroectodermal tumors of the spine: a comprehensive review with illustrative clinical cases

Primary spinal primitive neuroectodermal tumors (PNETs) are uncommon malignancies that are increasingly reported in the literature. Spinal PNETs, like their cranial counterparts, are aggressive tumors and patients with these tumors typically have short survival times despite maximal surgery, chemotherapy, and radiation. Because no standard management guidelines exist for treating these tumors, a multitude of therapeutic strategies have been employed with varying success. In this study the authors perform a comprehensive review of the literature on primary spinal PNETs and provide 2 new cases that highlight the salient features of their clinical management.

Peripheral primitive neuroectodermal tumor causing cauda equina syndrome with destruction of L5 vertebra

A 24-year-old male patient presented with cauda equina lesion symptoms. His clinicoradiological examination including X-rays, CT scan and MRI revealed destruction of L(5) vertebral body, pedicle and a mass extending to lateral recess and left intervertebral foramina causing pressure over the thecal sac. A CT guided FNAC was inconclusive. Open biopsy and hemilaminectomy of L(5) vertebra was performed. Histopathology and immunocytochemical analysis revealed it to be primitive neuroectodermal tumor. Patient was given chemotherapy and radiation therapy. His lower limb power improved by grade I post operatively and at 2 years follow-up bowel/bladder recovery was noticed. Patient died after 2.5 years of surgery because of pulmonary metastasis.