High-dose chemotherapy with autologous stem cell rescue for brain tumors

Novel Strategy Involving High-Dose Chemotherapy with Stem Cell Rescue Followed by Intrathecal Topotecan Maintenance Therapy without Whole-Brain Irradiation for Atypical Teratoid/Rhabdoid Tumors

Atypical teratoid/rhabdoid tumor (AT/RT) is a rare aggressive central nervous system tumor that typically affects children under three years old and has poor survival with a high risk for neurologic deficits. The primary purpose of this study was to successfully treat the disease and delay or avoid whole-brain radiotherapy for children with AT/RT. A retrospective analysis was performed for six children diagnosed with AT/RT and treated with multimodal treatment at a single institute between 2014 and 2020. Furthermore, germline SMARCB1 aberrations and MGMT methylation status of the tumors were analyzed. One patient who did not receive a modified IRS-III regimen replaced with ifosphamide, carboplatin, and etoposide (ICE) in induction chemotherapy was excluded from this analysis. Five patients who received ICE therapy were under three years old. After a surgical approach, they received intensive chemotherapy and high-dose chemotherapy with autologous peripheral blood stem cell transplantation (HDCT/autoPBSCT) followed by intrathecal topotecan maintenance therapy. Three patients underwent single HDCT/autoPBSCT, and the other two received sequential treatment. Two patients with germline SMARCB1 aberrations and metastases died of progressive AT/RT or therapy-related malignancy, while 3 with localized tumors without germline SMARCB1 aberrations remained alive. One survivor received local radiotherapy only, while the other two did not undergo radiotherapy. All three surviving patients were able to avoid whole-brain radiotherapy. Our results suggest that AT/RT patients with localized tumors without germline SMARCB1 aberrations can be rescued with multimodal therapy, including induction therapy containing ICE followed by HDCT/autoPBSCT and intrathecal topotecan maintenance therapy without radiotherapy. Further large-scale studies are necessary to confirm this hypothesis.

Brain biomarkers and neuropsychological outcomes of pediatric posterior fossa brain tumor survivors treated with surgical resection with or without adjuvant chemotherapy

PURPOSE

Children with brain tumors experience cognitive late effects, often related to cranial radiation. We sought to determine differential effects of surgery and chemotherapy on brain structure and neuropsychological outcomes in children who did not receive cranial radiation therapy (CRT).

METHODS

Twenty-eight children with a history of posterior fossa tumor (17 treated with surgery, 11 treated with surgery and chemotherapy) underwent neuroimaging and neuropsychological assessment a mean of 4.5 years (surgery group) to 9 years (surgery + chemotherapy group) posttreatment, along with 18 healthy sibling controls. Psychometric measures assessed IQ, language, executive functions, processing speed, memory, and social-emotional functioning. Group differences and correlations between diffusion tensor imaging findings and psychometric scores were examined.

RESULTS

The z-score mapping demonstrated fractional anisotropy (FA) values were ≥2 standard deviations lower in white matter tracts, prefrontal cortex gray matter, hippocampus, thalamus, basal ganglia, and pons between patient groups, indicating microstructural damage associated with chemotherapy. Patients scored lower than controls on visuoconstructional reasoning and memory (P ≤ .02). Lower FA in the uncinate fasciculus (R = -0.82 to -0.91) and higher FA in the thalamus (R = 0.73-0.91) associated with higher IQ scores, and higher FA in the thalamus associated with higher scores on spatial working memory (R = 0.82).

CONCLUSIONS

Posterior fossa brain tumor treatment with surgery and chemotherapy affects brain microstructure and neuropsychological functioning years into survivorship, with spatial processes the most vulnerable. Biomarkers indicating cellular changes in the thalamus, hippocampus, pons, prefrontal cortex, and white matter tracts associate with lower psychometric scores.

The impact on outcomes by using thiotepa in tandem transplant for pediatric high-risk embryonal brain tumors

BACKGROUND

Despite aggressive treatment including surgery, radiotherapy, and adjuvant chemotherapy, the outcome of pediatric high-risk embryonal brain tumors remains poor; especially in young children, in whom early radiotherapy inevitably brings significant long-term morbidities. Single or tandem autologous stem cell transplant has been reported to improve outcomes; but optimal use is not well defined.

METHODS

Pediatric patients with high-risk embryonal brain tumors who underwent tandem transplant as consolidation from August 2011 to December 2017 were included. We performed a retrospective chart review and analyzed the outcomes to identify possible prognostic factors.

RESULTS

Eleven pediatric patients with high-risk embryonal brain tumors were enrolled. They received double or triple autologous transplant at complete response in 5 patients and at partial response in 6 for a total of 24 transplants. There were five atypical teratoid rhabdoid tumors, four medulloblastoma, one primitive neuroectodermal tumors, and one pineoblastoma. Median age at diagnosis was 1.8 years (range, 0.6-11.2 years) and at transplant was 2.2 years (range, 1.2-11.9 years). Thiotepa-based regimens were used in 13 cycles of conditioning. All patients achieved successful engraftment. No transplant-related mortality was identified. With a median follow-up of 21.2 months (range, 6.9-51.8 months), seven patients had disease progression. Disease entity and the use of one or more cycles of thiotepa-based regimen during tandem transplant had statistically significant impact on both progression-free survival and overall survival.

CONCLUSION

With successful engraftment and manageable toxicity, tandem transplant in pediatric patients with high-risk embryonal brain tumor is feasible and safe. Patients receiving tandem transplant with one or more cycles of thiotepa-based regimen might have better outcome than those without. In combination with salvage radiotherapy, a favorable 2-year overall survival could be achieved in the majority of patients.

Marrow-ablative chemotherapy followed by tandem autologous hematopoietic cell transplantation in pediatric patients with malignant brain tumors

To improve survival in young children with malignant brain tumors, irradiation-avoiding or -minimizing marrow-ablative chemotherapy (HDCx) with autologous hematopoietic cell transplantation (AuHCT) has been investigated. We evaluated the outcome of 44 children with malignant brain tumors treated with HDCx and tandem AuHCT at Children's Hospital Los Angeles between June 1999 and July 2012. Forty-four children with malignant brain tumors were studied. Twenty-one had medulloblastoma/primitive neuro-ectodermal tumor, eight atypical teratoid/rhabdoid tumor (ATRT), five high-grade glioma, four malignant germ cell tumor, three ependymoma and three choroid plexus carcinoma. Twenty-nine patients received three tandem transplants and 15 received two tandem transplants, respectively. The 5-year PFS and overall survivals (OS) for all patients were 46.3±8.2% and 51.7±8.5%, respectively. The PFS and OS for 27 newly diagnosed patients were 68.9±9.9% and 73.5±9.3%, respectively, compared with 17 transplanted at relapse 11.8±9.8% (P<0.001) and 15.1±12.3% (P=0.0231), respectively. The 5-year PFS and OS in 13 previously unirradiated patients were 74±13% and 74±13% versus 33.2±9.8% and 40.2±10.6% in 31 irradiated patients (P=0.11 and P=0.239), respectively. One patient died of transplant-related toxicity. HDCx with tandem AuHCT is feasible and safe in children with malignant brain tumors with encouraging irradiation-free survival in newly diagnosed children.

High-grade glioma in very young children: a rare and particular patient population

In the past years, pediatric high-grade gliomas (HGG) have been the focus of several research articles and reviews, given the recent discoveries on the genetic and molecular levels pointing out a clinico-biological uniqueness of the pediatric population compared to their adult counterparts with HGG. On the other hand, there are only scarce data about HGG in very young children (below 3 years of age at diagnosis) due to their relatively low incidence. However, the few available data suggest further distinction of this very rare subgroup from older children and adults at several levels including their molecular and biological characteristics, their treatment management, as well as their outcome. This review summarizes and discusses the current available knowledge on the epidemiological, neuropathological, genetic and molecular data of this subpopulation. We discuss these findings and differences compared to older patients suffering from the same histologic disease. In addition, we highlight the particular clinical and neuro-radiological findings in this specific subgroup of patients as well as their current management approaches and treatment outcomes.

Proposed strategy for the use of high-dose chemotherapy with stem cell rescue and intrathecal topotecan without whole-brain irradiation for infantile classic medulloblastoma

We describe a 6-month-old infant with classic medulloblastoma. Gross total resection of the left cerebellar tumor was performed; however, relapse occurred during the administration of intrathecal and intravenous methotrexate-based chemotherapy. After undergoing resection, high-dose chemotherapy was administered consisting of topotecan, melphalan, and cyclophosphamide with autologous peripheral stem cell rescue followed by local irradiation and intrathecal topotecan, which resulted in a complete response for more than two years. The administration of high-dose chemotherapy followed by intrathecal topotecan as maintenance therapy is an effective strategy, without losses in the cognitive function, for avoiding the use of whole-brain irradiation for infantile classic medulloblastoma.

Atypical teratoid rhabdoid tumor: improved long-term survival with an intensive multimodal therapy and delayed radiotherapy. The Medical University of Vienna Experience 1992-2012

Atypical teratoid rhabdoid tumors (ATRTs) are recently defined highly aggressive embryonal central nervous system tumors with a poor prognosis and no definitive guidelines for treatment. We report on the importance of an initial correct diagnosis and disease-specific therapy on outcome in 22 consecutive patients and propose a new treatment strategy. From 1992 to 2012, nine patients initially diagnosed correctly as ATRT (cohort A, median age 24 months) were treated according to an intensive multimodal regimen (MUV-ATRT) consisting of three 9-week courses of a dose-dense regimen including doxorubicin, cyclophosphamide, vincristine, ifosfamide, cisplatin, etoposide, and methotrexate augmented with intrathecal therapy, followed by high-dose chemotherapy (HDCT) and completed with local radiotherapy. Thirteen patients were treated differently (cohort B, median age 30 months) most of whom according to protocols in use for their respective diagnoses. As of July 2013, 5-year overall survival (OS) and event-free survival (EFS) for all 22 consecutive patients was 56.3 ± 11.3% and 52.9 ± 11.0%, respectively. For MUV-ATRT regimen-treated patients (cohort A) 5-year OS was 100% and EFS was 88.9 ± 10.5%. For patients treated differently (cohort B) 5-year OS and EFS were 28.8 ± 13.1%. All nine MUV-ATRT regimen-treated patients are alive for a median of 76 months (range: 16–197), eight in first complete remission. Our results compare favorably to previously published data. The drug combination and sequence used in the proposed MUV-ATRT regimen appear to be efficacious in preventing early relapses also in young children with M1–M3 stage disease allowing postponement of radiotherapy until after HDCT.

The adolescent and young adult with cancer: state of the art--brain tumor

The management of adolescents and young adults with brain tumors, which consist of many different histologic subtypes, continues to be a challenge. Better outcome with a decrease of the side effects of the disease and therapy and improvement of quality of life has been demonstrated in recent decades for some tumors. Significant differences in survival and cure are also observed between adult and pediatric tumors of the same histologic grade. Genetic, developmental, and environmental factors likely influence the type of tumor and response observed, even though no clear pathologic features differentiate these lesions among children, adolescents, and adults. Similarly, treatment strategies are not identical among these populations; most patients receive surgery, followed by radiation therapy and multiagent chemotherapy. Advances in understanding the biology underlying the distribution of tumors in adolescents and young adults may influence the development of prospective trials. A more individualized view of these tumors will likely influence stratification of patients in future studies as well as selection for targeted agents. Accordingly, outcomes may improve and long-term morbidities may decrease.

Phase I study of tandem high-dose chemotherapy with autologous peripheral blood stem cell rescue for children with recurrent brain tumors: a Pediatric Blood and MarrowTransplant Consortium study

BACKGROUND

High-dose chemotherapy with autologous stem cell rescue (HDC/SCR) has produced responses and prolonged survival for some children with recurrent brain tumors, but is associated with considerable morbidity and mortality. A Phase I trial of two cycles of HDC/SCR for recurrent brain tumors in children was performed to determine the maximum tolerated doses for a novel regimen.

PROCEDURES

Two cycles of HDC/SCR were given. Cycle 1 included thiotepa and carmustine given on days -5, -4, and -3. Four to six weeks later, patients received cycle 2 which included thiotepa and carboplatin given on days -5, -4, and -3. Autologous peripheral blood stem cells (PBSC) were infused on day 0 of each cycle.

RESULTS

Thirty-two patients were treated and 25 patients received both cycles of HDC/SCR. Common toxicities included mucositis, emesis, diarrhea, anorexia, and pancytopenia. Eight of 32 (25%) assessable children died from regimen-related toxicity. Pulmonary failure occurred in seven patients. Seven patients had grade 3-4 neurotoxicity. The 3-year event-free survival (EFS) was 25%.

CONCLUSIONS

We determined the maximum tolerated regimen to be thiotepa 600 mg/m(2) and carmustine 300 mg/m(2) followed by thiotepa 600 mg/m(2) and carboplatin 1,200 mg/m(2) . Pulmonary toxicity was considerable. The toxic death rate was similar to other trials of HDC/SCR for children with recurrent brain tumors performed during the same time period. The regimen resulted in prolonged time to progression for a significant number of patients and long-term survival for some patients with recurrent medulloblastoma and rhabdoid tumor.

High-dose chemotherapy with autologous hematopoietic stem-cell rescue for pediatric brain tumor patients: a single institution experience from UCLA

Background. Dose-dependent response makes certain pediatric brain tumors appropriate targets for high-dose chemotherapy with autologous hematopoietic stem-cell rescue (HDCT-AHSCR). Methods. The clinical outcomes and toxicities were analyzed retrospectively for 18 consecutive patients ≤19 y/o treated with HDCT-AHSCR at UCLA (1999-2009). Results. Patients' median age was 2.3 years. Fourteen had primary and 4 recurrent tumors: 12 neural/embryonal (7 medulloblastomas, 4 primitive neuroectodermal tumors, and a pineoblastoma), 3 glial/mixed, and 3 germ cell tumors. Eight patients had initial gross-total and seven subtotal resections. HDCT mostly consisted of carboplatin and/or thiotepa ± etoposide (n = 16). Nine patients underwent a single AHSCR and nine ≥3 tandems. Three-year progression-free and overall survival probabilities were 60.5% ± 16 and 69.3% ± 11.5. Ten patients with pre-AHSCR complete remissions were alive/disease-free, whereas 5 of 8 with measurable disease were deceased (median followup: 2.3 yrs). Nine of 13 survivors avoided radiation. Single AHSCR regimens had greater toxicity than ≥3 AHSCR (P < .01). Conclusion. HDCT-AHSCR has a definitive, though limited role for selected pediatric brain tumors with poor prognosis and pretransplant complete/partial remissions.

TH1 predominance is associated with improved survival in pediatric medulloblastoma patients

Medulloblastoma, a primitive neuro-ectodermal tumor that arises in the posterior fossa, is the most common malignant brain tumor occurring in childhood. Even though 60-70% of children with medulloblastoma will be cured with intensive multimodal therapy, including surgery, radiotherapy, and chemotherapy, a significant proportion of surviving patients may suffer from long-term treatment-related sequelae. Therapeutic success is limited especially in younger children by radiotherapy-induced neurocognitive longterm deficits. In order to avoid or delay craniospinal radiotherapy, high-dose chemotherapy followed by autologous stem cell transplantation (HSCT) has become an established treatment modality. Data on the host immunologic environment in medulloblastoma patients are rare, notably data on cytokine expression and immune reconstitution in patients with medulloblastoma undergoing HSCT are lacking. In this present study, we therefore decided to prospectively assess immune function following 24 consecutive autologous HSCT in 17 children with medulloblastoma treated according to the German-Austrian-Swiss HIT-2000-protocol. TH1 predominance was found to be the most important factor for probability of survival. Already before HSCT, survivors showed higher IFNγ levels in sera as well as higher numbers of IFNγ-positive T-cells. After transplantation, this effect was even more pronounced. Patients with higher numbers of IFNγ- and TNFα-positive T-cells had a more favorable outcome at all analyzed time points. In addition, patients in complete remission (CR) before transplantation, known to have a better prognosis a priori, showed higher expression of IFNγ in T-cells. Taken together, this is the first report to demonstrate that high expression of IFNγ and TNFα in T-cells of medulloblastoma patients in the early post-transplant period correlates with a better prognosis. Our data point toward a potentially important influence of TH1-cytokine expression before and after transplantation on the survival of pediatric medulloblastoma patients.

Brain Tumors: From Childhood Through Adolescence Into Adulthood

The transition from childhood to adulthood through adolescence has been clearly identified as a time of great physical, psychological, emotional, social, and sexual change. Clinical care is currently divided into adult or pediatric care; adolescent patients require specific expertise that most clinical practices do not have. When illness coincides with the adolescent transition, the health system is severely challenged. Health systems historically have varied widely in the age they choose for allocating an individual to the adult model of health care. Tumors of the CNS complicate the difficult adjustments required in adolescents and young adults by virtue of their morbidity, complex treatment, and prognosis. Some brain tumors are unique to children, some occur predominantly in adults, and others peak in adolescence. Delays in the diagnosis of brain tumors can occur at any age but are particularly common in adolescence because of difficulties of accessing health systems, the difficulties of discriminating pathologic from typical adolescent behavioral characteristics, and changing endocrine function. Coming to terms with the cancer diagnosis; coping personally, socially, and financially with cancer treatments; accepting the risk of a shortened life span; confronting acquired disability; and coping with complex rehabilitation and adjusted plans for life are challenges for which there are no established specialist health models. This article will discuss the changing brain tumor profile of children, adolescents, and adults, with a focus on our limited understanding of the adolescent/young adult transition period.

Overcoming the challenges in the effective delivery of chemotherapies to CNS solid tumors

Locoregional therapies, such as surgery and intratumoral chemotherapy, do not effectively treat infiltrative primary CNS solid tumors and multifocal metastatic solid tumor disease of the CNS. It also remains a challenge to treat such CNS malignant solid tumor disease with systemic chemotherapies, although these lipid-soluble small-molecule drugs demonstrate potent cytotoxicity in vitro. Even in the setting of a 'normalized' tumor microenvironment, small-molecule drugs do not accumulate to effective concentrations in the vast majority of tumor cells, which is due to the fact that small-molecule drugs have short blood half-lives. It has been recently shown that drug-conjugated spherical lipid-insoluble nanoparticles within the 7-10 nm size range can deliver therapeutic concentrations of drug fraction directly into individual tumor cells following systemic administration, since these functionalized particles maintain peak blood concentrations for several hours and are smaller than the physiologic upper limit of pore size in the VEGF-derived blood capillaries of solid tumors, which is approximately 12 nm. In this article, the physiologic and ultrastructural basis of this novel translational approach for the treatment of CNS, as well as non-CNS, solid cancers is reviewed.

Fetal and neonatal rhabdoid tumor

PURPOSE

Few studies have focused on the behavior of rhabdoid tumor (RT) in the fetus and neonate. The purpose of this review is to show that perinatal RTs are associated with unusual findings and a poor prognosis.

METHODS

The author conducted a 40-year systematic review of the literature. Clinical presentation, pathology, management, and outcome of 72 fetuses and neonates with RTs are discussed.

RESULTS

Seventy-two fetuses and neonates presented with RTs detected prenatally (n = 12) and during the neonatal period (n = 60). The review consisted of 3 main groups: extrarenal noncentral nervous system (CNS) RT, renal RT, and CNS RT. There were some group differences in survival: extrarenal non-CNS RT (3/33 or 9.1%), renal RT (2/27 or 7.4%), and CNS RT (2/12 or 16.7%). Metastatic RT was present at diagnosis in more than half the patients (41/72 or 57%) who had a survival of 2.3%. The overall survival was 9.7%. For statistical results, there was no significant difference in survival among the 3 groups by type of tumor (P = .692). chi(2) analysis for survival with and without metastases was not valid due to small sample size.

CONCLUSIONS

The review shows that extrarenal RT was more common than either renal RT or CNS RT groups that is different than that observed in older individuals. Concomitant brain tumors were found in almost a third of fetuses and neonates. The CNS involvement occurred more often in patients with renal RT than in those with extrarenal RT. Metastatic disease at diagnosis was noted in more than half of the patients. Higher stage and presence of a CNS tumor were significant determinants in survival.

Recent progress towards development of effective systemic chemotherapy for the treatment of malignant brain tumors

Systemic chemotherapy has been relatively ineffective in the treatment of malignant brain tumors even though systemic chemotherapy drugs are small molecules that can readily extravasate across the porous blood-brain tumor barrier of malignant brain tumor microvasculature. Small molecule systemic chemotherapy drugs maintain peak blood concentrations for only minutes, and therefore, do not accumulate to therapeutic concentrations within individual brain tumor cells. The physiologic upper limit of pore size in the blood-brain tumor barrier of malignant brain tumor microvasculature is approximately 12 nanometers. Spherical nanoparticles ranging between 7 nm and 10 nm in diameter maintain peak blood concentrations for several hours and are sufficiently smaller than the 12 nm physiologic upper limit of pore size in the blood-brain tumor barrier to accumulate to therapeutic concentrations within individual brain tumor cells. Therefore, nanoparticles bearing chemotherapy that are within the 7 to 10 nm size range can be used to deliver therapeutic concentrations of small molecule chemotherapy drugs across the blood-brain tumor barrier into individual brain tumor cells. The initial therapeutic efficacy of the Gd-G5-doxorubicin dendrimer, an imageable nanoparticle bearing chemotherapy within the 7 to 10 nm size range, has been demonstrated in the orthotopic RG-2 rodent malignant glioma model. Herein I discuss this novel strategy to improve the effectiveness of systemic chemotherapy for the treatment of malignant brain tumors and the therapeutic implications thereof.

Current concepts in stereotactic radiosurgery - a neurosurgical and radiooncological point of view

Stereotactic radiosurgery is related to the history of "radiotherapy" and "stereotactic neurosurgery". The concepts for neurosurgeons and radiooncologists have been changed during the last decade and have also transformed neurosurgery. The gamma knife and the stereotactically modified linear accelerator (LINAC) are radiosurgical equipments to treat predetermined intracranial targets through the intact skull without damaging the surrounding normal brain tissue. These technical developments allow a more precise intracranial lesion control and offer even more conformal dose plans for irregularly shaped lesions. Histological determination by stereotactic biopsy remains the basis for any otherwise undefined intracranial lesion. As a minimal approach, it allows functional preservation, low risk and high sensitivity. Long-term results have been published for various indications. The impact of radiosurgery is presented for the management of gliomas, metastases, brain stem lesions, benign tumours and vascular malformations and selected functional disorders such as trigeminal neuralgia. In AVM's it can be performed as part of a multimodality strategy including resection or endovascular embolisation. Finally, the technological advances in radiation oncology as well as stereotactic neurosurgery have led to significant improvements in radiosurgical treatment opportunities. Novel indications are currently under investigation. The combination of both, the neurosurgical and the radiooncological expertise, will help to minimize the risk for the patient while achieving a greater treatment success.

Banking on cord blood stem cells

Umbilical cord blood gifted to non-profit public cord blood banks is now routinely used as an alternative source of haematopoietic stem cells for allogeneic transplantation for children and adults with cancer, bone marrow failure syndromes, haemoglobinopathies and many genetic metabolic disorders. Because of the success and outcomes of public cord banking, many companies now provide private cord banking services. However, in the absence of any published transplant evidence to support autologous and non-directed family banking, commercial cord banks currently offer a superfluous service.

Feasibility of metronomic maintenance chemotherapy following high-dose chemotherapy for malignant central nervous system tumors

BACKGROUND

Children less than 5 years of age with malignant central nervous system (CNS) tumors, continue to have a high rate of morbidity and mortality following administration of conventional therapy. In an attempt to avoid the neurologic sequelae associated with craniospinal radiation, strategies such as high-dose chemotherapy (HDCT) followed by peripheral stem cell rescue have been used successfully. Metronomic chemotherapy has also been reported as a potential new treatment strategy in solid tumors, particularly in adults.

PROCEDURE

A retrospective chart analysis was performed on 10 patients less than 5 years of age with CNS tumors treated with metronomic chemotherapy shortly after HDCT as part of their clinical care.

RESULTS

Metronomic chemotherapy was associated with minimal toxicity and all patients maintained a good quality of life. At the time of this report, all 10 patients are alive. Two patients have relapsed, and the remaining eight, including six patients with metastatic disease, continue to have stable clinical and radiographic disease at a mean of 20 months from the time of diagnosis.

CONCLUSIONS

Metronomic chemotherapy in this patient population is feasible and shows encouraging preliminary results, especially in patients with metastatic disease who have not received craniospinal radiation. Further investigation of this strategy in newly diagnosed patients with CNS tumors is warranted.

Outcome for children <4 years of age with malignant central nervous system tumors treated with high-dose chemotherapy and autologous stem cell rescue

BACKGROUND

Children <4 years of age (yo) with malignant central nervous system (CNS) tumors have a dismal prognosis. In an attempt to delay or obviate radiation therapy (XRT) and improve outcome, our institution has treated children <4 yo with newly diagnosed malignant CNS tumors with high-dose chemotherapy (HDC) and autologous stem cell rescue (ASCR) followed by selective XRT.

PROCEDURE

Fifteen children (age 4-38 months) with malignant CNS tumors have completed treatment with HDC/ASCR. All patients received three cycles of induction chemotherapy (cisplatin 3.5 mg/kg- day 0, cyclophosphamide 60 mg/kg- day 1 and 2, etoposide 2.5 mg/kg- day 0-2, vincristine 0.05 mg/kg, day 0, 7, 14) followed by three cycles of HDC (carboplatin 17 mg/kg and thiotepa 6 mg/kg, day 0 and 1) with ASCR. Histology included five medulloblastomas, four primitive neuroectodermal tumors (PNET), five malignant gliomas, and one ependymoma. Outcome and treatment toxicities were evaluated by retrospective chart review.

RESULTS

Median follow-up time of the 15 patients is 22 months (range 8-82 months). The 1- and 2-year progression-free survival (PFS) is 86.1% and 52.2% and overall survival (OS) 91.6% and 72.1%, respectively. Ten patients are alive and disease free 3-77 months (median 18 months) after having completed HDC/ASCR, thereoff five received XRT. Toxicity was primarily myelosuppression. There was no treatment mortality.

CONCLUSIONS

We are encouraged by the outcome of 15 children <4 yo with malignant CNS tumors treated with tandem cycles of HDC and ASCR at our institution. The treatment regimen is relatively well tolerated.

New concepts in the treatment of brain tumors in very young children

The treatment of brain tumors in infants (children <3 years of age) in the last 15-20 years has been a special field of interest for clinical investigation and research, since infants affected by brain tumors are an ideal experimental group of patients. New treatment strategies (conventional, myeloablative and intraventricular chemotherapy) have been tested on these patients in an effort to avoid or delay conventional irradiation. The amazing amount of knowledge that has been acquired from neuropathological and biological studies, as well as from the first generation treatment baby protocols, which were designed between 1985 and 2000, is now leading to a new approach whereby treatment strategies are tailored to the patient's clinicopathological features.

Efficacy of vincristine and etoposide with escalating cyclophosphamide in poor-prognosis pediatric brain tumors

The objective of this study was to assess the efficacy of the VETOPEC regimen, a regimen of vincristine and etoposide with escalating doses of cyclophosphamide (CPA), in pediatric patients with high-risk brain tumors. Three consecutive studies by the Australia and New Zealand Children's Cancer Study Group--VETOPEC I, Baby Brain 91, and VETOPEC II--have used a specific chemotherapy regimen of vincristine (VCR), etoposide (VP-16) and escalating CPA in patients with relapsed, refractory, or high-risk solid tumors. Patients in the VETOPEC II cohort were treated with very high dose CPA with peripheral blood stem cell (PBSC) rescue. We analyzed the subset of patients with high-risk brain tumors treated with these intensive VETOPEC-based protocols to assess the response, toxicity, and survival. We also assessed whether the use of very high dose chemotherapy with stem cell rescue improved the response rate or affected toxicity. Seventy-one brain tumor patients were treated with VETOPEC-based protocols. Of the 54 patients evaluable for tumor response, 17 had a complete response (CR) and 20 a partial response (PR) to treatment, which yielded an overall response rate of 69%. The CR + PR was 83% (19/23) for medulloblastomas, 56% (5/9) for primitive neuroectodermal tumors, 55% (6/11) for grade 3 and 4 astrocytomas, and 80% (6/8) for ependymomas. At a median follow-up of 36 months, overall survival for the entire cohort of 71 patients was 32%, with event-free survival of 13%. There were no toxic deaths within the PBSC-supported VETOPEC II cohort, despite higher CPA doses, compared with 7% among the non-PBSC patients. This regimen produces high response rates in a variety of very poor prognosis pediatric brain tumors. The maximum tolerated dose of CPA was not reached. Higher escalation in doses of CPA did not deliver a further improvement in response. With PBSC rescue in the VETOPEC II study, hematologic toxicity was no longer a limiting factor. The response rates observed support further development of this chemotherapy regimen.

National estimates of the use of hematopoietic stem-cell transplantation in children with cancer in the United States

National utilization data for hematopoietic stem-cell transplantation (HSCT) for childhood cancers in the United States have not been reported. We identified cancer encounters for children aged 18 years and younger from 1997 to 2001 in US nonfederal, acute care hospitals. We compared patient, hospital, and resource use characteristics and in-patient mortality associated with HSCT and non-HSCT encounters, estimated the number of HSCT encounters by stem-cell source and cancer type, and examined resource use and mortality in each category. We identified 461,175 cancer encounters, of which 6380 (1.4%) were HSCT encounters. There was wide variation in resource use and mortality by stem-cell source and cancer type. Of note, 17% of HSCT encounters were for patients with acute lymphoblastic leukemia without remission or sarcoma, conditions for which there is little evidence of benefit from HSCT in children. These encounters were associated with high in-patient mortality and long lengths of stay. Also, we observed an increasing use of cord blood over the study period. Future research should examine potentially important sociodemographic differences in patients undergoing HSCT compared to those who do not. Additional analyses incorporating disease stage and severity are needed.

Evolving role of myeloablative chemotherapy in the treatment of childhood brain tumours

Primary brain tumours, a heterogeneous group of cancer that constitute the second most common cancer in childhood, were historically treated with neurosurgical resection and radiation therapy. Chemotherapy has proven to be beneficial for some histological types, which has since led to exploration of the role of high-dose chemotherapy and haematopoietic stem cell rescue. Patients with high-grade glial tumours, primitive neuroectodermal tumours and high-risk medulloblastoma usually fare poorly. The indicators of bad prognosis are metastatic status, extent of resection and age. Children <3 years at diagnosis carry worse prognosis. Rare cancers such as ependymoblastoma, atypical teratoid rhabdoid tumour and choroid plexus carcinoma have a dismal prognosis regardless of the above-mentioned indicators. The use of myeloablative therapy (MAT) has been investigated to improve the rate of long-term DFS, as well as to reduce and delay in the youngest children the use of the craniospinal irradiation associated with unacceptable late effects. We will overview the literature regarding patients with 'good and uncertain indications' to MAT. Ependymoma and brain stem tumours, for which the available data discourage the use of MAT, are excluded. Finally, we will summarize a single Institution experience (Giannina Gaslini Children's Hospital, Genoa) with MAT in the period 1997-2003.

High-dose chemotherapy with autologous stem cell rescue for children with high risk and recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors

Current treatment for high risk and recurrent medulloblastoma (MB) and supratentorial primitive neuroectodermal tumors (stPNET) has a very poor prognosis in children. High dose chemotherapy (HDCT) and autologous stem cell rescue have improved survival rates. We present 19 patients (thirteen classified in the high risk group and six patients with recurrent disease) that received HDCT and autologous stem cell rescue. In the high risk group [Med Pediatr Oncol 38 (2002) 83], all patients underwent neurosurgical debulking. Standard chemotherapy was prescribed in 10 patients. Radiotherapy was given to 4 patients (all older than 4 years old). In the recurrence disease group [Childs Nerv Syst 15 (1999) 498], five patients underwent surgery. Radiotherapy was given to those who were not previously irradiated. The HDCT in twelve patients consisted of busulfan 4 mg/kg/day, orally over 4 days in 6-hourly divided doses and melphalan at a dose of 140 mg/m2/day by intravenous infusion over 5 min on day -1. Three patients additionally received thiotepa 250 mg/m2/day intravenously over 2 days and four patients additionally received topotecan 2 mg/m2/day over 5 days by intravenous infusion over 30 min. The other seven patients received busulfan and thiotepa at the same doses.Patient's stem cells were mobilized with granulocyte colony-stimulating factor at a dose of 12 microg/kg twice daily subcutaneously for four consecutive days. Cryopreserved peripheral blood progenitor cells were re-infused 48 h after completion of chemotherapy. With a median follow-up of 34 months (range 5-93) eight complete responses and one partial response were observed. Three patients died of treatment-related toxicities (15%). The 2 year event-free survival was 37.67+/-14% in all patients and 57+/-15% for the high risk group. Therefore we conclude that HDCT may improve survival rates in patients with high risk/recurrent MB and stPNET despite treatment toxicity.

Central nervous system atypical teratoid/rhabdoid tumor: results of therapy in children enrolled in a registry

PURPOSE

Atypical teratoid/rhabdoid tumor (AT/RT) of the CNS is an extremely rare and aggressive tumor of early childhood. The poor outcome with conventional infant brain tumor therapy has resulted in a lack of clear treatment guidelines. A registry has been established to create an outcomes database and to facilitate biology studies for this tumor.

MATERIALS AND METHODS

A standardized data sheet was provided to treating physicians listing the reports that were to be sent to the registry for abstraction. Follow-up information was sought twice yearly.

RESULTS

Information was complete for 42 patients. Median age at diagnosis was 24 months. Nine patients (21%) had disseminated disease at diagnosis. Sixteen tumors were infratentorial; 26 were supratentorial. Twenty patients (48%) received a primary complete resection. Primary therapy included chemotherapy in all patients, radiotherapy in 13 patients (31%), stem-cell rescue in 13 patients (31%), and intrathecal chemotherapy in 16 patients (38%). Recurrent or progressive disease was reported in nine and 19 patients, respectively. Twenty-seven patients (64%) are dead of disease (3 to 62 months from diagnosis) and one patient died of toxicity. Fourteen patients (33%) show no evidence of disease (9.5 to 96 months from diagnosis). The median survival is 16.75 months and the median event-free survival is 10 months.

CONCLUSION

Aggressive therapy has prolonged the natural history in a subset of children. Prospective multi-institutional and national clinical trials designed specifically for AT/RT are needed. Enrollment onto the AT/RT registry should be continued.

Safety and efficacy of high-dose chemotherapy with autologous stem cell transplantation for patients with malignant astrocytomas

BACKGROUND

Malignant astrocytomas are among the most resistant tumors to curative treatments. Mean survival without treatment is measured in weeks, and even with maximal surgery and radiation, the mean reported survival is < 1 year. The advent of supportive treatments and newer agents has resulted in benefits for many patients with cancer. The authors investigated the safety and effect on survival of a high-dose thiotepa and carboplatin regimen with autologous stem cell transplantation (ASCT) in patients with malignant astrocytomas who were enrolled in a prospective trial approved by an institutional review board (IRB).

METHODS

Twenty-one patients were enrolled in an IRB-approved, prospective trial. After baseline testing was completed, patients underwent peripheral stem cell mobilization with cyclophosphamide (4 g/m2) and etoposide (450 mg/m2) followed by granulocyte-colony-stimulating factor (10 microg/kg). Peripheral stem cells were harvested when leukocyte counts recovered. Patients received 2 cycles of thiotepa (750 mg/m2) and carboplatin (1600 mg/m2) followed by infusion of the preserved stem cells. The cycles were administered 6-10 weeks apart. Primary outcome measures were patient survival (Kaplan-Meier analysis) and treatment toxicity (using National Cancer Institute common toxicity criteria).

RESULTS

Autologous stem cells were harvested effectively and transfused in all patients. Kaplan-Meier survival analysis demonstrated a survival time of 34.3 +/- 5.5 months (range, 9-94 months). Despite significant myelosuppression, only three patients experienced Grade 4 complications and eight experienced Grade 3 complications.

CONCLUSIONS

High-dose chemotherapy with thiotepa and carboplatin with concomitant ASCT was used safely to treat patients with malignant astrocytomas and may provide a survival advantage.

Thiotepa-Based High-Dose Chemotherapy With Autologous Stem-Cell Rescue in Patients With Recurrent or Progressive CNS Germ Cell Tumors

Purpose

To evaluate the efficacy and toxicity of high-dose chemotherapy (HDC) followed by autologous stem-cell rescue (ASCR) in patients with relapsed or progressive CNS germ cell tumors (GCTs).

Patients and Methods

Twenty-one patients with CNS GCTs who experienced relapse or progression despite having received initial chemotherapy and/or radiotherapy were treated with thiotepa-based HDC regimens followed by ASCR.

Results

Estimated overall survival (OS) and event-free survival (EFS) rates for the entire group 4 years after HDC were 57% ± 12% and 52% ± 14%, respectively. Seven of nine (78%) patients with germinoma survived disease-free after HDC with a median survival of 48 months. One patient died as a result of progressive disease (PD) 39 months after HDC, and another died as a result of pulmonary fibrosis unrelated to HDC 78 months after ASCR without assessable disease. However, only four of 12 patients (33%) with nongerminomatous germ cell tumors (NGGCTs) survived without evidence of disease, with a median survival of 35 months. Eight patients with NGGCTs died as a result of PD, with a median survival of 4 months after HDC (range, 2 to 17 months). Patients with germinoma fared better than those with NGGCTs (P = .016 and .014 for OS and EFS, respectively). Patients with complete response to HDC also had significantly better outcome (P < .001 for OS and EFS) compared with patients with only a partial response or stable disease. There were no toxic deaths because of HDC.

Conclusion

Dose escalation of chemotherapy followed by ASCR is effective therapy for patients with recurrent CNS germinomas and might be effective in patients with recurrent NGGCTs with a low tumor burden.

Trasplante autólogo con progenitores hematopoyéticos de sangre periférica en niños con tumores del sistema nervioso central de alto riesgo

BACKGROUND

In the last few years, survival in children with central nervous system (CNS) tumors has slightly improved, especially in children with tumors such as medulloblastoma and those in which complete surgical resection is achieved. However, outcome remains poor in patients with incomplete surgical resection, neuroaxial dissemination, metastatic or recurrent tumors and in very young children.

OBJECTIVES

To improve prognosis in patients with high-risk and recurrent tumors, new therapeutic strategies such as high-dose chemotherapy with autologous stem cell rescue (ASCR) have been developed.

METHODS

We retrospectively studied patients with high-risk and recurrent CNS tumors who underwent ASCR between September 1995 and December 2002 in our unit.

RESULTS

Thirty-five patients underwent ASCR. Seven patients died of treatment-related toxicities (20 %). Thirteen (37 %) are event-free survivors at a median post-ASCR follow-up of 18 months (range: 5-63 months). The 2-year Kaplan-Meier estimates of event-free survival was 37.64 +/- 8.7 % in all patients, 57 +/- 15 % in the group of patients with high-risk medulloblastoma/supratentorial primitive neuroectodermal tumor (stPNET) and 71.43 +/- 17 % in patients aged less than 4 years with medulloblastoma/stPNET.

CONCLUSIONS

In our experience, ASCR may be effective in the treatment of malignant tumors of the central nervous system in patients with controlled disease, in certain histologic groups and chemosensitive tumors (medulloblastoma, malignant astrocytoma), as well as in very young children in whom cranial radiotherapy is contraindicated.

Gliomas del tronco encefálico

Brainstem gliomas have been increasingly understood in the last two decades and they are nowadays regarded as an heterogeneous group of tumors with tendency towards the pediatric age, where they account for 10-20% of brain neoplasms. Besides the well known diffuse tumor, several subtypes, with a different biological behaviour, amenable to surgical resection and better prognosis, have been identified, giving rise to many classifications and terms. In the other way, attention has been recently paid to adult brainstem gliomas in contrast to pediatric tumors. Based on a review of the literature, we describe the different subtypes of brainstem gliomas, with particular interest on therapeutic approaches and differences between pediatric and adult tumors, employing iconography from our series.

High-dose thiotepa and etoposide in children with poor-prognosis brain tumors

BACKGROUND

Outcome data were analyzed for 27 patients who were affected with recurrent or newly diagnosed high-risk brain tumors and who underwent high-dose chemotherapy with triethylenethiophosphoramide (thiotepa) and etoposide in addition to autologous stem cell transplantation between May 1992 and September 2002.

METHODS

Fifteen males and 12 females (median age, 11 years) were included in the study. Twelve patients had newly diagnosed high-risk brain tumors, and 15 patients had recurrent brain tumors. The conditioning regimen consisted of thiotepa 900 mg/m2 and etoposide 1500 mg/m2 over 3 days starting on Day -5. Stem cell rescue was performed using bone marrow (BM) in 8 patients, peripheral blood stem cells (PBSCs) in 18 patients, and BM and PBSCs in 1 patient.

RESULTS

For the BM group, neutrophil (PMN) engraftment was achieved on Day +14 (median value), whereas platelet (PLT) engraftment was achieved on Day +68 (median value). One patient did not achieve PLT engraftment. For the PBSC group, the PMN engraftment was achieved on Day +10.0 (median value), and the PLT engraftment was achieved on Day +15.5 (median value). Transplantation-related toxicity (evaluated using the Bearman score) included Grade 2-3 mucositis in 16 patients, Grade 1 kidney toxicity in 6 patients, Grade 1 liver toxicity in 6 patients, and Grade 2 liver toxicity in 1 patient. Transplantation-related mortality was observed in 1 patient (3.6%), who died of Candida pneumonia. The 3-year overall survival (OS) rate was 44.6%, and the 3-year event-free survival (EFS) rate was 31%. There was a statistically significant difference in OS and EFS rates for patients who underwent ASCT and achieved complete remission compared with patients who had measurable disease.

CONCLUSIONS

The results of the current study suggest that high-dose chemotherapy followed by ASCT may be beneficial for patients who achieve complete remission before ASCT, whereas for other patients, new strategies are required.

Medulloblastomas and central nervous system primitive neuroectodermal tumors

Significant advances in the treatment of medulloblastoma and primitive neuroectodermal tumors have been made in the past three decades. Maximal surgical resection is a mainstay of therapy. However, unlike many other central nervous system neoplasms, medulloblastoma and primitive neuroectodermal tumors are radiation and chemotherapy responsive. Despite this response, the prognosis for patients with these tumors remains variable and is relatively poor in infants and patients with metastatic disease. These tumors most commonly arise in children, thus most clinical trials emphasize the reduction of long-term sequelae, in addition to improving survival. All newly diagnosed patients who are eligible should be offered participation in a clinical trial. If a patient is ineligible or declines consent/assent for a clinical trial, the best current treatment approach is surgical resection, followed by radiation therapy (except for children younger than 3 years) with weekly vincristine. For high-risk patients, 36 Gy of craniospinal irradiation should be delivered plus a boost of 19.8 Gy to the posterior fossa/primary tumor bed and sites of bulk metastatic disease. For average-risk patients, the craniospinal irradiation dose may be lowered to 23.4 Gy plus 32.4 Gy to the posterior fossa/tumor bed. After radiation therapy, intensive multimodal chemotherapy should be used for all patients.