Histopathologic and immunohistochemical profile of spinal glioblastoma: a study of six cases

Surgical approaches to intramedullary spinal cord astrocytomas in the age of genomics

Intramedullary astrocytomas represent approximately 30%–40% of all intramedullary tumors and are the most common intramedullary tumor in children. Surgical resection is considered the mainstay of treatment in symptomatic patients with neurological deficits. Gross total resection (GTR) can be difficult to achieve as astrocytomas frequently present as diffuse lesions that infiltrate the cord. Therefore, GTR carries a substantial risk of new post-operative deficits. Consequently, subtotal resection and biopsy are often the only surgical options attempted. A midline or paramedian sulcal myelotomy is frequently used for surgical resection, although a dorsal root entry zone myelotomy can be used for lateral tumors. Intra-operative neuromonitoring using D-wave integrity, somatosensory, and motor evoked potentials is critical to facilitating a safe resection. Adjuvant radiation and chemotherapy, such as temozolomide, are often administered for high-grade recurrent or progressive lesions; however, consensus is lacking on their efficacy. Biopsied tumors can be analyzed for molecular markers that inform clinicians about the tumor’s prognosis and response to conventional as well as targeted therapeutic treatments. Stratification of intramedullary tumors is increasingly based on molecular features and mutational status. The landscape of genetic and epigenetic mutations in intramedullary astrocytomas is not equivalent to their intracranial counterparts, with important difference in frequency and type of mutations. Therefore, dedicated attention is needed to cohorts of patients with intramedullary tumors. Targeted therapeutic agents can be designed and administered to patients based on their mutational status, which may be used in coordination with traditional surgical resection to improve overall survival and functional status.

Surgical treatment and neurological outcome of infiltrating intramedullary astrocytoma WHO II-IV: a multicenter retrospective case series

Introduction

Primary malignant spinal astrocytomas present rare oncological entities with limited median survival and rapid neurological deterioration. Evidence on surgical therapy, adjuvant treatment, and neurological outcome is sparse. We aim to describe the treatment algorithm and clinical features on patients with infiltrating intramedullary astrocytomas graded WHO II–IV.

Methods

The following is a multicentered retrospective study of patients treated for spinal malignant glioma WHO II–IV in five high-volume neurosurgical departments from 2008 to 2019. Pilocytic astrocytomas were excluded. We assessed data on surgical technique, perioperative neurological status, adjuvant oncological therapy, and clinical outcome.

Results

40 patients were included (diffuse astrocytoma WHO II n = 11, anaplastic astrocytoma WHO III n = 12, WHO IV n = 17). Only 40% were functionally independent before surgery, most patients presented with moderate disability (47.5%). Most patients underwent a biopsy (n = 18, 45%) or subtotal tumor resection (n = 15, 37.5%), and 49% of the patients deteriorated after surgery. Patients with WHO III and IV tumors were treated with combined radiochemotherapy. Median overall survival (OS) was 46.5 months in WHO II, 25.7 months in WHO III, and 7.4 months in WHO IV astrocytomas. Preoperative clinical status and WHO significantly influenced the OS, and the extent of resection did not.

Conclusion

Infiltrating intramedullary astrocytomas WHO II–IV present rare entities with dismal prognosis. Due to the high incidence of surgery-related neurological impairment, the aim of the surgical approach should be limited to obtaining the histological tissue via a biopsy or, tumor debulking in cases with rapidly progressive severe preoperative deficits.

Glioblastoma Multiforme of the Conus Medullaris—Management Strategies and Complications

Primary spinal glioblastoma multiforme (GBM) of the conus medullaris is a rare and devastating pathologic entity. The presenting symptoms commonly include progressive neurologic deficits in the lower extremities, bowel and bladder dysfunction, and low back pain. Histologically, these tumors have high-grade features similar to their intracranial counterparts. However, recent advancements in the field of molecular oncology have been beginning to elucidate a unique molecular blueprint for these spinal gliomas. Given the lack of standardized treatment strategies, we have presented our institutional experience in treating a small series of patients with conus medullaris GBM and have reviewed the reported data on the relevant molecular markers, management strategies, and complication avoidance for this malignant pathologic entity.

Molecular Biomarkers of Brain and Spinal Cord Astrocytomas

Spinal cord astrocytomas are rare diseases of the central nervous system. The localization of these tumors and their infiltrative growth complicate their surgical resection, increase the risk of postoperative complications, and require more careful use of radio- and chemotherapy. The information on the genetic mutations associated with the onset and development of astrocytomas provides a more accurate neoplasm diagnosis and classification. In some cases, it also allows one to determine the optimal methods for treating the neoplasm, as well as to predict the treatment outcomes and the risks of relapse. To date, a number of molecular markers that are associated with brain astrocytomas and possess prognostic value have been identified and described. Due to the significantly lower incidence of spinal cord astrocytomas, the data on similar markers are much more sparse and are presented with a lesser degree of systematization. However, due to the retrospective studies of clinical material that have been actively conducted abroad in recent years, the formation of statistically significant genetic landscapes for various types of tumors, including intradural spinal cord tumors, has begun. In this regard, the purpose of this review is to analyze and systematize the information on the most significant genetic mutations associated with various types of astrocytomas, as well as discuss the prospects for using the corresponding molecular markers for diagnostic and prognostic purposes.

Primary Spinal Cord Small-Cell Glioblastoma: Case Report and Literature Review

BACKGROUND

Approximately 2%-10% of all central nervous system tumors are primary spinal cord tumors (SCTs). Spinal cord glioblastoma is a rare tumor type accounting for 1%-3% of all SCTs and 7.5% of all spinal cord gliomas. Notably, the small-cell variant of spinal cord glioblastoma is even rarer with only 2 previously reported cases.

CASE DESCRIPTION

We present herein a case report of a rare primary spinal cord glioblastoma in a 48-year-old patient with a 2-month history of numbness in the left arm and mild cervical pain radiating to the occipital zone. Clinical examination revealed hypoalgesia and thermal dissociation of the left arm and the ipsilateral superior part of the trunk treated through subtotal surgical resection followed by adjuvant chemotherapy and radiotherapy. Histologic examination of the surgical tumor specimen revealed features of the small-cell spinal cord glioblastoma.

CONCLUSIONS

To the best of our knowledge, this is only the third reported case of small-cell spinal cord glioblastoma. The aggressive nature of this tumor variant reduces overall survival rate regardless of the treatment.

Primary Spinal Cord Glioblastoma Multiforme: A Retrospective Study of Patients at a Single Institution

BACKGROUND AND OBJECTIVE

Primary spinal cord (PSC) glioblastoma multiforme (GBM) is extremely rare and accounts for only 1.5% of all spinal cord tumors. Therefore, its treatment is still ill defined. To elucidate prognostic factors, we performed a single-institutional retrospective review of the largest series to date of patients with PSC GBM who underwent surgical resection in West China Hospital between 2008 and 2014. A total of 14 patients with PSC GBM were reviewed.

METHODS

Demographic, operative, and postoperative factors were recorded. Overall survival (OS) and progression-free survival (PFS) were calculated and compared with the Kaplan-Meier method.

RESULTS

Eight males (57%) and 6 females (43%) were involved in the study. Their median age was 28 years (range, 14-56 years). Median Karnofsky Performance Status score was 60 (range, 20-90). Four patients (28.6%) received gross total resection, 5 (35.7%) partial resection, and the remaining 5 (35.7%) biopsy only. Nine patients (64.3%) received postoperative radiotherapy and chemotherapy, 3 (21.4%) chemotherapy only, and 2 (14.3%) neither. Median follow-up period was 15 months (range, 5-26 months). One-year and 2-year survival was 78.5% (11/14) and 7.1% (1/14), respectively. Median OS was 15 months, and median PFS 8 months. Univariate log-rank analysis showed that OS and PFS were significantly associated with patients' age (P = 0.007 and P = 0.04, respectively) and postoperative radiotherapy (P = 0.001 and P = 0.002, respectively). However, preoperative Karnofsky Performance Status score affected only OS and did not affect PFS (P = 0.033 and P = 0.106, respectively).

CONCLUSIONS

According to our study, the combination of postoperative radiotherapy and temozolomide chemotherapy can improve prognosis and may serve as a feasible postoperative adjuvant treatment of PSC GBM.

Glioblastoma multiforme in conus medullaris with intracranial metastasis after postoperative adjuvant therapy

Spinal glioblastoma multiforme is not common among spinal cord tumors. According to our literature review, only 27 cases originating from the conus medullaris were reported. We herein reported a case of a 10-year-old child diagnosed with glioblastoma multiforme. The patient received adjuvant radiotherapy and standard temozolomide chemotherapy after total excision. Intracranial lesions were found 1 month after postoperative adjuvant therapy. We described the clinical characteristics and postoperative therapy of the patient, and reviewed all of the published cases of conus medullaris glioblastoma. Location, age, leptomeningeal spread, and secondary hydrocephalus may be predictive factors. Immunohistochemical factors such as p53 and Ki-67 are also important. Combined treatment of surgery and postoperative adjuvant therapy is commonly used, but is controversial.

The involvement of hematopoietic pre-B cell leukemia transcription factor-interacting protein in regulating epithelial-mesenchymal transition of human spinal glioblastoma

To date, hematopoietic pre-B cell leukemia transcription factor-interacting protein (HPIP), a co-repressor for the transcription factor PBX, has been involved into the initiation and onset in a wide variety of cancers. However, the molecular mechanisms underlying HPIP-induced epithelial-mesenchymal transition (EMT) in the spinal glioblastoma have been under investigation. In the present study, spinal glioblastoma tissues, U87, and U251 cell lines were used and subjected to in vitro assays, such as RT-PCR, and Western blot. Here, in vitro assays revealed that HPIP mRNA and protein were highly expressed in five cases of spinal glioblastoma tissues, compared with non-tumor tissues. Subsequently, in vitro experiments demonstrated HPIP promoted the U87 and U251 cell growth and regulated the G1/S phase transitions in U87 and U251 cell cycle, respectively, accompanied by the increased expression of cyclin A2, cyclin B1, and cyclin D1. Furthermore, HPIP increased the expression of N-cadherin, Slug, and MMP2, and decreased the expression of E-cadherin. By contrast, knockdown of HPIP reversed HPIP-induced EMT biomarkers, migration, and invasion in U87 and U251 cells. In conclusion, our findings identified HPIP plays an important role in the progression and EMT of spinal glioblastoma, by which cell growth is improved. Thus, HPIP gene or protein could act as a useful target in the clinical practice.

The genetic basis of intradural spinal tumors and its impact on clinical treatment

Genetic alterations in the cells of intradural spinal tumors can have a significant impact on the treatment options, counseling, and prognosis for patients. Although surgery is the primary therapy for most intradural tumors, radiochemothera-peutic modalities and targeted interventions play an ever-evolving role in treating aggressive cancers and in addressing cancer recurrence in long-term survivors. Recent studies have helped delineate specific genetic and molecular differences between intradural spinal tumors and their intracranial counterparts and have also identified significant variation in therapeutic effects on these tumors. This review discusses the genetic and molecular alterations in the most common intradural spinal tumors in both adult and pediatrie patients, including nerve sheath tumors (that is, neurofibroma and schwannoma), meningioma, ependymoma, astrocytoma (that is, low-grade glioma, anaplastic astrocytoma, and glioblastoma), hemangioblastoma, and medulloblastoma. It also examines the genetics of metastatic tumors to the spinal cord, arising either from the CNS or from systemic sources. Importantly, the impact of this knowledge on therapeutic options and its application to clinical practice are discussed.

Spinal cord tumours: advances in genetics and their implications for treatment

Tumours of the spinal cord, although rare, are associated with high morbidity. Surgical resection remains the primary treatment for patients with this disease, and offers the best chance for cure. Such surgical procedures, however, carry substantial risks such as worsening of neurological deficit, paralysis and death. New therapeutic avenues for spinal cord tumours are needed, but genetic studies of the molecular mechanisms governing tumourigenesis in the spinal cord are limited by the scarcity of high-quality human tumour samples. Many spinal cord tumours have intracranial counterparts that have been extensively studied, but emerging data show that the tumours are genetically and biologically distinct. The differences between brain and spine tumours make extrapolation of data from one to the other difficult. In this Review, we describe the demographics, genetics and current treatment approaches for the most commonly encountered spinal cord tumours--namely, ependymomas, astrocytomas, haemangioblastomas and meningiomas. We highlight advances in understanding of the biological basis of these lesions, and explain how the latest progress in genetics and beyond are being translated to improve patient care.