Successful treatment of childhood intramedullary spinal cord astrocytomas with irinotecan and cisplatin

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 Management of Intramedullary Spinal Cord Tumors

Intramedullary spinal cord tumors (IMSCT) comprise a rare subset of CNS tumors that have distinct management strategies based on histopathology. These tumors often present challenges in regards to optimal timing for surgery, invasiveness, and recurrence. Advances in microsurgical techniques and technological adjuncts have improved extent of resection and outcomes with IMSCT. Furthermore, adjuvant therapies including targeted immunotherapies and image-guided radiation therapy have witnessed rapid development over the past decade, further improving survival for many of these patients. In this review, we provide an overview of types, epidemiology, imaging characteristics, surgical management strategies, and future areas of research for IMSCT.

Updates in the management of intradural spinal cord tumors: a radiation oncology focus

Primary spinal cord tumors represent a hetereogeneous group of central nervous system malignancies whose management is complex given the relatively uncommon nature of the disease and variety of tumor subtypes, functional neurologic deficits from the tumor, and potential morbidities associated with definitive treatment. Advances in neuroimaging; integration of diagnostic, prognostic, and predictive molecular testing into tumor classification; and developments in neurosurgical techniques have refined the current role of radiotherapy in the multimodal management of patients with primary spinal cord tumors, and corroborated the need for prospective, multidisciplinary discussion and treatment decision making. Radiotherapeutic technological advances have dramatically improved the entire continuum from treatment planning to treatment delivery, and the development of stereotactic radiosurgery and proton radiotherapy provides new radiotherapy options for patients treated in the definitive, adjuvant, or salvage setting. The objective of this comprehensive review is to provide a contemporary overview of the management of primary intradural spinal cord tumors, with a focus on radiotherapy.

[Contribution of temozolomide chemotherapy for intramedullary grade II spinal cord astrocytomas in adults: Our experience]

INTRODUCTION

Grade II intramedullary astrocytomas are rare tumors. Despite a well-defined role of adjuvant temozolomide chemotherapy for brain gliomas, the contribution of this therapy for intramedullary gliomas is not yet clearly defined.

METHOD

We retrospectively analyzed the data of 5 adult patients treated with temozolomide between 2008 and 2015 for a grade II intramedullary astrocytoma with progression after surgery.

RESULTS

Five patients from 19 to 70 years of age (median, 37years) underwent a second surgery for the progression of a grade II intramedullary astrocytoma (median progression-free survival 26months [8-90]). All tumors remained grade II. Due to a second clinical or/and radiological tumor progression, the patients were treated with temozolomide after a 37months median progression-free survival (5-66). All patients received at minimum 12 cycles (mean 14 ± 5; range 12-24) of temozolomide (150-200mg/m²/day, 5days/28days). All patients were alive after a 10-year median follow-up after diagnosis (6-13). All patients were able to walk except one, who was previously in McCormick autonomy grade IV before chemotherapy. The McCormick autonomy rating after temozolomide was stable for 4 patients and improved for 1 patient. The treatment was delayed once for hematological toxicity.

CONCLUSION

Temozolomide stabilized all 5 patients without any major toxicity. Based on this experience that needs to be confirmed, we consider that temozolomide should be envisaged within the therapeutic arsenal for progressive intramedullary grade II astrocytomas.

Pediatric spinal cord astrocytomas: a retrospective study of 348 patients from the SEER database

OBJECTIVE Intramedullary spinal cord tumors comprise 1%-10% of all childhood central nervous system neoplasms, with astrocytomas representing the most common subtype. Due to their rarity and poor prognosis, large population-based studies are needed to assess the epidemiology and survival risk factors associated with these tumors in the hope of improving outcome. The authors undertook this retrospective study to explore factors that may influence survival in pediatric patients with spinal cord astrocytomas. METHODS Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, a prospective cancer registry, the authors retrospectively assessed survival in histologically confirmed, primary spinal cord astrocytomas in patients 21 years of age and younger. Survival was described with Kaplan-Meyer curves, and a multivariate regression analysis was used to assess the association of several variables with survival while controlling for confounding variables. RESULTS This analysis of 348 cases showed that age (hazard ratio [HR] 1.05, 95% CI 1.01-1.09, p = 0.017), nonwhite race (HR 1.74, 95% CI 1.11-2.74, p = 0.014), high-grade tumor status (HR 14.67, 95% CI 6.69-32.14, p < 0.001), distant or invasive extension of the tumor (HR 2.37, 95% CI 1.02-5.49, p = 0.046), and radiation therapy (HR 3.74, 95% CI 2.18-6.41, p < 0.001) were associated with decreased survival. Partial resection (HR 0.37, 95% CI 0.16-0.83, p = 0.017) and gross-total resection (HR 0.39, 95% CI 0.16-0.95, p = 0.039) were associated with improved survival. CONCLUSIONS Younger age appears to be protective, while high-grade tumors have a much worse prognosis. Early diagnosis and access to surgery appears necessary for improving outcomes, while radiation therapy has an unclear role. There is still much to learn about this disease in the hope of curing children with the misfortune of having one of these rare tumors.

Primary spinal glioma in children: Results from a referral pediatric institution in Shanghai

PURPOSE

Primary spinal cord glioma is a rare entity especially in children; accounting for less than 10% of all central nervous system tumors. Low grade is the most reported subtype. Treatment modalities have largely evolved; large improvements have been made in the surgical field but also in both of radiotherapy and chemotherapy. Nevertheless, the optimal treatment is yet to be defined.

MATERIAL AND METHODS

A chart review of 11 pediatric patients with a diagnosis of low grade spinal cord glioma at Xhinhua hospital in Shanghai was conducted. A statistical package for Social Sciences Package (SPSS) was used for analysis. Means and standard deviations were calculated. The Kaplan-Meier method was used to analyze overall survival and progression-free survival.

RESULTS

The mean age was 6.7 years (range: 6 months-14.3 years). Revealing symptoms were variable and slowly progressive. The mean duration of symptoms prior to diagnosis was of 7±3.2 months. Astrocytoma was the most commonly reported histological type (seven cases, 63.6%), ependymomas were reported in three cases (27.3%). Surgery was performed in all patients. Subtotal resection concerned the majority of patients (nine patients, 81.8%). Adjuvant radiotherapy was indicated in all cases. A total dose of 39.6Gy was delivered to the whole group. Three patients received adjuvant chemotherapy, of whom two patients had grade III glioma and one patient had a tumor recurrence. Temozolomide-based regimen was the main protocol used for all our patients. The 3 years overall survival rate was 100%, whereas the progression free survival rate was 87.5%. One case relapsed during the next year following completion of treatment.

CONCLUSION

Our preliminary results are consistent with that of other similar published reports, however longer follow up is needed. So are specific recommendations that are still lacking in this setting.

Low-grade gliomas in children: single institutional experience in 198 cases

INTRODUCTION

In pediatric population (0-18 years), low-grade gliomas (PLGG) are the most frequent brain tumors and majority are amenable for surgical removal.

PATIENTS AND METHODS

A retrospective review of 198 children diagnosed with PLGG between 1980 and 2010 at HSJD was carried out. Several variables were studied to find prognostic factors related to the outcomes (progression-free survival (PFS) and overall survival (OS)).

RESULTS

Median age at onset was 88.8 months (3.1 to 214.5 months, SD 53). Surgery was performed in 175 patients (88.4%), achieving gross total resection (GTR) in 77 (44%), subtotal resection (STR) in 87 (49.7%), and 11 (6.3%) biopsies. Pathological review classified 84 tumors as WHO grade I (48%) and 89 as grade II (50.8%). Adjuvant therapy (AT) was given to 75 patients (37.9%), radiotherapy in 24 (12.1%), chemotherapy in 33 (16.7%), and combined in 18 (9.1%). Sixteen patients (8.1%) died, 89 (43.4%) are alive with no evidence of disease, and 93 (47%) alive with disease, median follow-up 65.2 months. Outcome is significantly correlated with age (p = 0001, worse OS for patients younger than 12 months) and extent of tumor resection (p < 0001). OS for GTR/STR/biopsy was >200, 154.3, and 101.9 months, respectively. Patients treated with AT presented worse OS/PFS (p < 0.001) than those not treated. Histology was non significantly related to outcomes.

CONCLUSION

In our series of PLGG, the best prognostic markers are tumor location (cerebellar) and the extent of tumor resection (GTR). Infants and patients who require adjuvant therapy because of tumor progression or recurrence have worse outcome.

Pediatric intramedullary spinal cord tumors: a single center experience

AIM

To evaluate clinical and radiological findings, pathological features and treatment modalities in pediatric patients with intramedullary spinal cord tumors.

PATIENTS AND METHODS

The medical records of 36 patients with intramedullary spinal tumors were reviewed for clinical, radiological and histopathological data, chemotherapy, radiotherapy, surgical resection, treatment responses, events, and final outcome. Survival analyses were performed.

RESULTS

The median age was 7.9 years (range: 1-16 years; male/female ratio:1.4). Majority of the tumors were histopathologically diagnosed as astrocytomas (n = 16, 44.4%) and ependymomas (n = 19, 52.8%); whereas one was unclassified glioma. Overall, 94% of the astrocytomas and 84% of the ependymomas were low-grade, only three tumors were high-grade. In one patient with ependymoma, histopathological grade was undetermined. The primary tumor was commonly located in thoracic (47%) and cervical segments (28%). All patients had undergone surgery (gross-total resection, 33%; subtotal resection, 45%; biopsy, 22%). Radiotherapy was administered to 26 patients (72%) and chemotherapy to 15 patients (42%). The 3-, 5- and 10-year overall survival rates were 72%, 63% and 56%, respectively; and event-free survival rates were 43%, 40% and 40%. Survival did not significantly differ with gender, age groups, lag-time, neurologic status, histopathological tumor type, tumor location, extent of resection, treatment, or treatment responses in univariate survival analyses. Survival rates were significantly higher in patients with low-grade tumors and in ependymoma patients with resected tumors.

CONCLUSIONS

Patients with low-grade tumors and those who underwent gross-total tumor resection had better prognosis. Surgery remains the main treatment in intramedullary spinal tumors. The role of radiotherapy and chemotherapy is limited and even controversial in low-grade tumors.

Brain stem tumors in children and adolescents: single institutional experience

PURPOSE

Pediatric brain stem tumors (BsT) are a heterogeneous group of diseases. Our aim was to analyze our experience to find out prognostic factors.

METHOD

A retrospective study with BsT patients was performed. Imaging characteristics, extension of surgery, pathology, and adjuvant therapy were analyzed and correlated with overall survival (OS) and progression-free survival (PFS) as outcome measures.

RESULT

Since 1980 to 2010, we analyzed 65 BsT patients, 41 of them girls (63%), median age of 8 years (range 13.9 months to 17.6 years). Twenty-two patients (33.8%) had diffuse intrinsic pontine gliomas (DIPG) and 43 (66.2%) presented with focal BsT. Histology was available in 42 patients; the most frequent is low-grade glioma in 24/42 patients (57%). DIPG's histology (obtained usually at necropsy) confirmed five high-grade gliomas. After median follow-up of 49.3 months (0.5-175 months), 20/22 DIPG patients have died (90.9%), while 27/43 with focal tumors were alive (62.8%). Variables related to outcome were histology (better for low-grade glioma (LGG) OS p < 0.001), surgery (better if operated OS p < 0.001), and adjuvant therapy (worse if given, PFS p = 0.001, OS p = 0.024). The outcome for DIPG was dismal, median OS/EFS of 14.2/9.4 months, significantly worse than focal BsT (p = 0.000), while OS/EFS was 122.8/87.2 months for focal intrinsic, 88.2/47.1 months for exophytic, and 124.4/54 months for cervico-medullary tumors: no differences were found among them, except the histology (OS p < 0.001 for low-grade vs high-grade tumors).

CONCLUSION

BsT in children comprised two different groups: diffuse (DIPG) and focal gliomas. The DIPGs continue having a dismal prognosis, needing new approaches, while focal tumors including LGG have better prognosis.

Treatment of spinal cord tumors

Tumors associated with the spinal cord can have devastating effects on patient function and quality of life. Most of these tumors are from metastatic disease, usually to the epidural space. Less frequently, the tumors are intrinsic to the spinal cord itself (ie, primary tumor). Regardless of the etiology, spinal cord tumors often present first with progressive local or radicular pain, or both. Other symptoms include weakness, sensory changes, or sphincter dysfunction. The timeliness of diagnosis of spinal cord tumors and promptness of treatment are important, as they directly affect outcome. Dexamethasone, a corticosteroid, is used as a temporizing measure to improve or stabilize neurologic function until definitive treatment. For nonambulatory patients with epidural metastatic tumors, surgery followed by radiation therapy maximizes neurologic function and modestly lengthens survival. However, palliative radiotherapy alone is recommended for those with neurologic deficits lasting longer than 48 hours, survival prognosis less than 3 months, inability to tolerate surgery, multiple areas of compression, or radiosensitive tumors. An ambulatory patient with a stable spine should be considered for radiation treatment only. The role of chemotherapy for epidural metastatic tumors is not well established. For intramedullary metastases, the role of surgery and chemotherapy remains controversial and radiation is the mainstay. For low-grade or benign primary spinal cord tumors, resective surgery is of benefit and can be curative. For high-grade tumors, the benefit of resection is less clear, and radiotherapy and/or chemotherapy may be helpful. The use of chemotherapy for primary spinal cord tumors has rarely been assessed. Agents reported in the literature for treatment of spinal cord gliomas include temozolomide, irinotecan, cisplatin, and carboplatin. A multidisciplinary approach is often required to maximize the therapeutic and functional outcome of patients with metastatic and primary spinal cord tumors.

Serine phosphorylation of glutathione S-transferase P1 (GSTP1) by PKCα enhances GSTP1-dependent cisplatin metabolism and resistance in human glioma cells

Recently, we reported that the human GSTP1 is phosphorylated and functionally activated by the PKC class of serine/threonine kinases. In this study, we investigated the contribution of this post-translational modification of GSTP1 to tumor cisplatin resistance. Using two malignant glioma cell lines, MGR1 and MGR3, the ability of PKCα-phosphorylated GSTP1 to catalyze the conjugation of cisplatin to glutathione was assessed and correlated with cisplatin sensitivity and cisplatin-induced DNA interstrand cross-links and apoptosis of the cells. The results showed PKCα activation and associated phosphorylation of GSTP1 to correlate significantly with increased glutathionylplatinum formation, decreased DNA interstrand cross-link formation and increased cisplatin resistance. Following PKC activation, the IC(50) of cisplatin increased from 13.63μM to 36.49μM in MGR1 and from 20.75μM to 38.45μM in MGR3. In both cell lines, siRNA-mediated GSTP1 or PKCα transcriptional suppression similarly decreased cisplatin IC(50) and was associated with decreased intracellular levels of glutathionylplatinum metabolite. Combined inhibition/transcriptional suppression of both PKCα and GSTP1 was synergistic in enhancing cisplatin sensitivity. Although, cisplatin-induced apoptosis was associated with the translocation of Bax to mitochondria, release of cytochrome c and caspase-3/7 activation, the levels of relocalized Bax and cytochrome c were significantly greater following GSTP1 knockdown. These results support a mechanism of cisplatin resistance mediated by the PKCα-dependent serine phosphorylation of GSTP1 and its associated increased cisplatin metabolism, and suggest the potential of simultaneous targeting of GSTP1 and PKCα to improve the efficacy of cisplatin therapy.

Primary intramedullary tumors of the spinal cord

STUDY DESIGN

Clinically based systematic review.

OBJECTIVE

To define optimal clinical care for primary intramedullary spinal cord tumors using a systematic review with expert opinion.

METHODS

Focused questions on the treatment of primary intramedullary spinal cord tumors were refined by a panel of spine oncology surgeons, medical and radiation oncologist. Keyword were searched through Medline database and pertinent abstracts and manuscripts obtained. The quality of literature was rated as high, moderate, low, or very low. Using the GRADE evidence based review system the proposed questions were answered using the literature review and expert opinion. These treatment recommendations were then rated as either strong or weak based on the quality of evidence and clinical expertise.

RESULTS

The literature searches revealed low and very low quality evidence with no prospective or randomized studies. The MEDLINE search engine returned 9000 articles which was restricted to articles about human subjects and written in the English language. The subsequent search resulted in a return of: "spinal cord tumor" (5053), "ependymoma" (580), "astrocytoma" (420), and "glioma" (235) articles. Seventeen articles referenced timing of surgical intervention and symptomatology for intramedullary spinal cord tumors. One hundred fifty-eight chemotherapy and 183 radiation therapy articles for intramedullary spinal cord tumors were reviewed.

CONCLUSION

The most important factor in determining the IMSCT patient's long-term neurologic and functional outcome after surgery is the patient's preoperative neurologic status. However, this must be taken in the context of the underlying tumor histology. Therefore, resection is reserved for progressive neurologic decline and serial monitoring for asymptomatic individuals. Adjuvant therapy is an option for high grade astrocytomas (WHO grades 3-4).

Intramedullary lesions of the conus medullaris: differential diagnosis and surgical management

The medullary conus represents a distinct entity of the spinal cord regarding its anatomical, clinical and microsurgical features. An overview of the pathologic processes of this region is provided. Epidemiological, clinical and neuroradiological characteristics of neoplastic (glial tumors, non-glial tumors, metastasis, primary melanomas) and non-neoplastic lesions (granulomatous lesions, abscess, parasitic infections, vascular, demyelinating and dysembryogenetic lesions) are discussed. Main MR imaging characteristics used to differentiate neoplastic from non-neoplastic lesions consist in pathological spinal cord expansion, gadolinium-enhancement and tumoural cyst formation. Management strategies differ substantially, depending on the kind of lesion. According to the suspected pathological entity radical resection, biopsy or conservative treatments are reasonable options. Intraoperative electrophysiological monitoring is a fundamental part of the surgical setting.

Temozolomide for recurrent low-grade spinal cord gliomas in adults

BACKGROUND

There is no standard therapy for surgery- and radiotherapy-resistant, recurrent, low-grade spinal cord gliomas. Therefore, a retrospective study of temozolomide (TMZ) in adults with recurrent low-grade spinal cord gliomas with a primary objective of determining progression-free survival (PFS) was performed.

METHODS

Twenty-two patients (11 men and 11 women) aged 20 years to 55 years (median, 35 years) with recurrent spinal cord gliomas (World Health Organization grade 2 astrocytoma in 19 patients and oligoastrocytoma in 3 patients) were treated. All had previously been treated with surgery and involved-field radiotherapy. Thirteen patients underwent repeat surgery. All patients were chemotherapy-naive. TMZ was administered at a dose of 150-200 mg/m(2)/day for 5 consecutive days every 4 weeks (operationally defined as a single cycle). Neurologic and neuroradiographic evaluations were performed every 8 weeks.

RESULTS

All patients were evaluable for toxicity and response. A total of 266 cycles of TMZ (median, 14 cycles; range, 2 cycles-24 cycles) was administered. TMZ-related toxicity included constipation (9 patients, 1 with grade 3), lymphopenia (9 patients, 1 with grade 3), fatigue (7 patients, 1 with grade 3), neutropenia (6 patients, 2 with grade 3), and thrombocytopenia (6 patients, 2 with grade 3). Four (18%) patients demonstrated a partial radiographic response, 12 (55%) demonstrated stable disease, and 6 (27%) had progressive disease after 2 cycles of TMZ. Time to tumor progression ranged from 2 months to 28 months (median, 14.5 months). Survival ranged from 4 months to 39 months (median, 23 months). PFS at 6 months, 12 months, 18 months, and 24 months was 64%, 64%, 41%, and 27%, respectively.

CONCLUSIONS

TMZ demonstrated modest efficacy with acceptable toxicity in this cohort of adult patients with recurrent low-grade spinal cord gliomas.