Childhood medulloblastoma: progress and future challenges

Medulloblastoma and other primitive neuroectodermal tumors are the most common malignant tumors of childhood. Progress has been slowly made in the management of such tumors. Long-term neurocognitive sequelae of treatment in children with medulloblastoma are common and recent treatment trials have attempted to reduce the amount of craniospinal radiation therapy or delay radiation therapy in attempts to reduce such sequelae. Surgery remains a critical component of treatment, although there is increasing concern about surgically-related complications, including the cerebellar mutism syndrome. For older children, craniospinal radiation remains an integral part of management. However, recent studies have suggested an excellent outcome after reduced-dose craniospinal radiation therapy and adjuvant chemotherapy. The role of chemotherapy is expanding for children with medulloblastoma and is now presently a component of protocols for children with average-risk and poor-risk disease. For children with poor-risk disease, intensifications of chemotherapy both during and after radiation therapy are presently being explored. Treatment of infants and young children with medulloblastoma remains problematic and a variety of different approaches are being investigated with the aims of both improving outcome and reducing long-term sequelae.

Current neurosurgical management and the impact of the extent of resection in the treatment of malignant gliomas of childhood: a report of the Children's Cancer Group trial no. CCG-945

OBJECT

One hundred seventy-two children with high-grade astrocytomas were treated by members of the Children's Cancer Group in a prospective randomized trial designed to evaluate the role of two chemotherapy regimens. Seventy-six percent of the patients (131 children) in whom a diagnosis of either anaplastic astrocytoma or glioblastoma multiforme was confirmed by central pathological review are the subject of this report.

METHODS

Patients were stratified according to the extent of tumor resection (biopsy [< 10%], partial resection [10-50%], subtotal resection [51-90%], near-total resection [> 90%], and total resection) as determined by surgical observation and postoperative computerized tomography scanning. Information on contemporary neurosurgical management was obtained from the patient's operative records and standardized neurosurgical report forms. The vast majority of tumors were supratentorial: 63% (83 tumors) in the superficial cerebral hemisphere, 28% (37 tumors) in the deep or midline cerebrum, and only 8% (11 tumors) in the posterior fossa. A significant association was detected between the primary tumor site and the extent of resection (p < 0.0001). A radical resection (> 90%) was performed in 37% of the children: 49% of the tumors in the superficial hemisphere and 45% of tumors in the posterior fossa compared with 8% of midline tumors. Tumor location could also be used to predict the need for both temporary and permanent cerebrospinal fluid (CSF) diversion. Half of the deep tumors and 8% of the hemispheric astrocytomas ultimately required a permanent CSF shunt. Improvement in preoperative neurological deficits and level of consciousness was seen in 36% and 34% of the children, respectively. New or increased deficits were present in 14% of the children, with 6% experiencing a diminished sensorium after surgery. Postoperative nonneurological complications were rare: infection, hematoma, and CSF fistula each occurred in 1.7% of the children. Univariate and multivariate analyses demonstrated that radical tumor resection (> 90%) was the only therapeutic variable that significantly improved progression-free survival (PFS) rates. For all patients with malignant astrocytomas, the distributions of PFS rates were significantly different (p = 0.006) following radical resection compared with less extensive (< or = 90%) resection. The 5-year PFS rates were 35 +/- 7% and 17 +/- 4%, respectively. The differences in the distribution of PFS rate were significant for the subsets of patients with anaplastic astrocytoma (p = 0.055) and glioblastoma multiforme (p = 0.046). The 5-year PFS rates for anaplastic astrocytoma were 44 +/- 11% and 22 +/- 6% for cases in which the tumor was radically resected and less than radically resected, respectively; whereas the 5-year PFS rates for glioblastoma multiforme were 26 +/- 9% and 4 +/- 3% for cases in which the tumor was radically resected and less than radically resected, respectively.

CONCLUSIONS

The demonstration of a survival advantage provided by radical resection should prompt neurosurgeons to treat malignant pediatric astrocytomas with aggressive surgical resection prior to initiation of radiotherapy or adjuvant chemotherapy.

Treatment of diencephalic syndrome with chemotherapy: growth, tumor response, and long term control

BACKGROUND

The diencephalic syndrome (DS), which is manifested by progressive emaciation and failure to thrive in an apparently alert, cheerful infant, usually is due to a low grade hypothalamic glioma. Treatment with aggressive surgery and/or radiotherapy is variably successful in controlling disease and may result in severe neurologic sequelae. Chemotherapy recently has been shown to be effective in patients with low grade gliomas of childhood, but it is used infrequently in those with DS.

METHODS

The authors evaluated the efficacy of a regimen of carboplatin and vincristine on improving weight, causing tumor shrinkage, and delaying the need for alternative therapies in seven children (ages 9-20 months; median age, 11 months) with DS. Five patients weighed less than the 5th percentile for their age at the start of the study, one weighed within the 10th percentile, and one weighed within the 25th percentile.

RESULTS

At follow-up (range, 6-54 months; median, 28 months), the patients' weights had increased by 66-95% (median, 80%). On magnetic resonance imaging, four patients had a >50% reduction in tumor mass, one had a 25-50% reduction, and two had stable disease. In those patients with radiographic response to treatment, weight gain was accomplished with oral feedings in four of five patients, whereas those with stable disease required nasogastric, nasojejunal, or gastrostomy tube supplementation to maintain weight. Disease progression occurred at a median of 24 months after initiation of chemotherapy, and two patients remained free of progressive disease at last follow-up. Five patients were alive a median of 59 months from diagnosis. The need for radiation or other therapies was delayed in six of seven children. Therapy was tolerated without significant toxicities.

CONCLUSION

The authors conclude that treatment of DS with a carboplatin and vincristine regimen results in demonstrable weight gain, may result in tumor shrinkage, and in some cases, significantly delays the need for alternative therapies.

Pediatric central nervous system tumors

Much of the recent change in the management of brain tumors in children has centered on the expanded use of chemotherapy. The addition of chemotherapy has resulted in better survival rates for children with medulloblastoma and altered the management for those with low-grade gliomas. For other tumor types, therapeutic advances have been slower. High-dose chemotherapy increasingly is being employed to treat malignant childhood tumors, with variable results.

Survival and prognostic factors following radiation therapy and chemotherapy for ependymomas in children: a report of the Children's Cancer Group

OBJECT

Ependymomas in children continue to generate controversy regarding their histological diagnosis and grading. optimal management, and possible prognostic factors. To increase our knowledge of these tumors the authors addressed these issues in a cohort of children with prospectively staged ependymomas treated with radiotherapy and chemotherapy.

METHODS

Children between the ages of 2 and 17.3 years harboring an intracranial ependymoma confirmed by a central review of the tumor's pathological characteristics were treated according to Children's Cancer Group Protocol 921 from 1986 to 1992. Treatment following surgery and postoperative tumor staging (including brain computerized tomography or magnetic resonance [MR] imaging, spinal MR imaging or myelography, and cerebrospinal fluid cytological investigation) included craniospinal irradiation with a local boost to the primary tumor and patient randomization to receive adjuvant chemotherapy with either 1) CCNU, vincristine, and prednisone, or 2) the eight-drugs-in-1-day regimen. Centralized review of the tumor pathological characteristics revealed 20 ependymomas and 12 anaplastic ependymomas in the 32 children included in the study. Diagnoses made at the individual institutions included anaplastic (malignant) ependymoma (15 patients), ependymoma (four patients), ependymoblastoma (nine patients), ependymoastrocytoma (one patient), and primitive neuroectodermal tumor (three patients), which were discordant with the centralized review diagnosis in 22 of 32 cases. Only three of the 32 patients had metastatic disease (two with M and one with M3 stages). At surgery, 47% of tumors were estimated to be totally resected. Among the 14 of 17 patients who suffered a relapse and were evaluated for site of relapse, 10 (71%) had an isolated local relapse, three (21%) had concurrent local and metastatic relapse, and only one (7%) had an isolated metastatic relapse. Kaplan-Meier estimates of 5-year progression-free survival (PFS) and overall survival rates were 50 +/- 10% and 64 +/- 9%, respectively.

CONCLUSIONS

Predictors of PFS duration included an estimate of the extent of resection made at surgery (total compared with less than total, p = 0.0001) and the amount of residual tumor on postoperative imaging as verified by centralized radiological review (< or = 1.5 cm2 compared with > 1.5 cm2, p < 0.0001). No other factors, including centrally reviewed tumor histopathological type, location, metastasis and tumor (M and T) stages, patient age, race, gender, or chemotherapy treatment regimen significantly correlated with PFS duration. The pattern of predominantly local relapse and the important influence of residual tumor or the extent of resection on PFS duration confirms a prevailing impression that local disease control is the major factor in the prediction of outcome of ependymoma. Survival rates were comparable with those reported by other investigators who have treated patients with similar doses of radiation and no chemotherapy.

Childhood tumors

Advances are slowly being made in the understanding and treatment of primary childhood brain tumors. The addition of chemotherapy has resulted in better survival for children with medulloblastoma. For other tumor types, therapeutic advances have been slower. High-dose chemotherapy is increasingly being employed to treat malignant childhood tumors, with variable results. Chemotherapy has been effective in low-grade glial tumors.

Childhood tumors

Slowly, advances are being made in the understanding and treatment of primary childhood brain tumors. The addition of chemotherapy has resulted in better survival for children with medulloblastoma. For other tumor types, therapeutic advances have been slower. High-dose chemotherapy is increasingly being employed to treat malignant childhood tumors with variable results. Chemotherapy has been effective in low-grade glial tumors.

Acute neurologic dysfunction associated with high-dose chemotherapy and autologous bone marrow rescue for primary malignant brain tumors

Acute neurologic complications occurred 103 times in 50 (54%) of 92 patients (primarily children) treated with high-dose chemotherapy and autologous bone marrow rescue for primary central nervous tumors. Different types of neurologic compromise occurred during the chemotherapy infusion as compared to the first 100 days after the chemotherapy and the greater-than-100-day time period. The causes of the neurologic compromise were also time sensitive.

BACKGROUND

Results of treatment for children with primary brain tumors using high-dose chemotherapy with autologous marrow rescue (ABMR) have been encouraging. However, the neurotoxicity associated with this technique remains a major concern. We reviewed the records of 92 patients who underwent ABMR for malignant brain tumors between 1986 and 1992 for the occurrence and timing of acute neurologic dysfunction (AND).

METHODS

Individual investigators at the participating institutions retrospectively completed standardized forms on each patient. The manner in which the distribution of AND versus time of treatment emerged led to the establishment of distinct time periods for data analysis and discussion. The pre-ABMR period included those events that occurred during the chemotherapy infusion, the early posttreatment period included the first 100 days following bone marrow rescue, and the late posttreatment period was greater than 100 days following bone marrow rescue.

RESULTS

Fifty patients (54%) had 103 episodes of AND. AND included encephalopathies with or without hallucinations or coma (32), seizures (23), headaches (9), ataxia-tremor-dysarthria syndrome (7), anorexia and nausea syndrome (7) and others (25). During the chemotherapy infusion, encephalopathies and seizures were most common. Hallucinations occurred primarily related to drug infusion, while encephalopathies without hallucinations were usually due to demonstrable dysmetabolic states. In the 100 days following ABMR, dysmetabolic states and iatrogenic factors caused 45% and progressive disease caused 33% of AND. Greater than 100 days from ABMR, progressive disease caused 55% of AND; 7 patients were noted to develop chronic anorexia and nausea of unclear etiology. The occurrence of neurologic compromise was not related to the chemotherapy regimens, tumor histology, tumor location, patient age, prior treatment, or the amount of tumor at time of treatment. Dexamethasone use was the only clinical factor associated with AND (p < 0.004).

CONCLUSIONS

The cause of AND was definable for 95% of instances that occurred within 100 days of ABMR. Early AND was often iatrogenic and reversible. The greater the time from ABMR the more likely AND was due to progressive disease. Clinical factors could not predict the occurrence of AND as only the concurrent use of dexamethasone at the time of treatment proved significant. Although frequent, AND should not be considered a limiting toxicity of this approach or preclude the use of this technique.

Pediatric congenital bilateral perisylvian syndrome: clinical and MRI features in 12 patients

In 1926, Foix, Chavany and Marie described an acquired syndrome of fasciopharyngoglossomasticatory diplegia resulting from bilateral infarction of the anterior operculum. Clinical features consisted of facial diplegia, dysarthria, pseudobulbar palsy, mild to severe mental retardation, and seizures. A developmental form, similar in presentation in adults with MRI findings consisting of bilateral perisylvian cortical malformation consistent with polymicrogyria involving the sylvian fissure and opercular cortex, has been recognized; but few pediatric cases of congenital bilateral perisylvian syndrome (CBPS) have been reported. Over the past four years, we have encountered 12 cases of CBPS presenting in childhood. Age ranges were from 1 week to 11 years with a median of 2.25 years; six were less than two years of age. Seven were male and five female. Ten had bilateral perisylvian polymicrogyria on MRI; two had unilateral perisylvian schizencephaly with contralateral perisylvian polymicrogyria. Clinical manifestations included developmental delay in 7; poor palatal function in 5; hypotonia in 4; arthrogryposis in 4; hemiparesis in 3; apnea in 3; paraparesis in 2; micrognathia in 2; pectus excavatum in 2; quadriparesis in 1; and hearing loss in 1. Seizures occurred in seven (58%) and consisted of infantile spasms (n = 1), generalized tonic-clonic (n = 1), complex partial (n = 2), partial motor (n = 2; 1 with secondary generalization), and febrile convulsions (n = 1). CBPS has different manifestations in the pediatric population than in adults. CBPS is more common than previously thought, is recognizable by MRI and should be suspected clinically in any infant or child presenting with oromotor dysfunction/pseudobulbar signs and developmental delay, especially if there are associated congenital malformations. Epilepsy is not a constant feature in the pediatric presentation and is variable in type and severity.

A phase I study of high-dose tamoxifen for the treatment of refractory malignant gliomas of childhood

Recent studies have indicated that the proliferation of malignant gliomas is in part dependent on excessive activation of protein kinase C (PKC)-mediated pathways. Conversely, inhibiting PKC may provide a novel approach for blocking glioma growth. The antiestrogen tamoxifen, a moderately potent PKC inhibitor, has been shown in vitro to block the proliferation of malignant glioma cell lines at concentrations several-fold higher than those typically attained during the treatment of breast cancer; such serum concentrations may be achieved with doses > 40 mg/m2 b.i.d. The safety and efficacy of these high doses for producing disease control in patients with malignant gliomas has recently been noted anecdotally, although a rigorous study of this agent has been lacking. To address this issue, we examined the safety and efficacy of high-dose tamoxifen in a series of children with malignant gliomas that had progressed after conventional therapy. An initial group was treated with 60 mg/m2 p.o. b.i.d. and a second group with 100 mg/m2 b.i.d. Steady-state serum tamoxifen and metabolite levels were measured in most patients. Toxicity with the regimen was minimal; two patients treated at the higher dose required reduction to the lower dose because of asymptomatic prolongation of the QT interval on an electrocardiogram. Although none of the patients exhibited clear-cut tumor regression, 4 of 14 patients had stabilization of previously progressive disease for at least 3 months; the longest survivor lived for 17 months after beginning tamoxifen. The moderate efficacy of this agent in otherwise end-stage disease coupled with its low toxicity and the relative ease of oral administration provides a rationale for proceeding with larger studies of this agent in patients with malignant gliomas, possibly as a means for potentiating the effects of conventional chemotherapeutic agents, which to date have shown limited efficacy in the treatment of these tumors.

Carboplatin and vincristine chemotherapy for children with newly diagnosed progressive low-grade gliomas

The optimum treatment of nonresectable low-grade gliomas of childhood remains undecided. There has been increased interest in the use of chemotherapy for young children, but little information concerning the long-term efficacy of such treatment. Seventy-eight children with a mean age of 3 years (range 3 months-16 years) who had newly diagnosed, progressive low-grade gliomas were treated with combined carboplatin and vincristine chemotherapy. The patients were followed for a median of 30 months from diagnosis, with 31 patients followed for more than 3 years. Fifty-eight children had diencephalic tumors, 12 had brainstem gliomas, and three had diffuse leptomeningeal gliomas. Forty-four (56%) of 78 patients showed an objective response to treatment. Progression-free survival rates were 75 +/- 6% at 2 years and 68 +/- 7% at 3 years. There was no statistical difference in progression-free survival rates between children with neurofibromatosis Type 1 and those without the disease (2-year, progression-free survival 79 +/- 11% vs. 75 +/- 6%, respectively). The histological subtype of the tumor, its location, and its maximum response to chemotherapy did not have an impact on the duration of disease control. The only significant prognostic factor was age: children 5 years old or younger at the time of treatment had a 3-year progression-free survival rate of 74 +/- 7% compared with a rate of 39 +/- 21% in older children (p < 0.01). Treatment with carboplatin and vincristine is effective, especially in younger children, in controlling newly diagnosed progressive low-grade gliomas.

Brain tumors in children

Primary central nervous system tumors are the second most common form of childhood cancer and the leading cancer-related cause of death and illness in children. Developments in neuroscience have led to an increasing understanding of these neoplasms, to alternations in their classification system, and to progress (albeit frustratingly slow progress) in their management. Chemotherapy has become an integral part of the treatment of many forms of childhood brain cancer, including medulloblastoma. Increasing evidence indicates that the amount of craniospinal radiation therapy required for diseases control can be reduced, possibly decreasing treatment-related sequelae, when this therapy is combined with postradiation chemotherapy. The value of the use of preradiation chemotherapy remains unproven. For other types of tumors, such as malignant high-grade gliomas and brainstem gliomas, new approaches to therapy have not yet resulted in improved outcomes. However, even for these tumors, advances in neuroimaging and new neurobiologic approaches hold substantial promise.

Pilot study of high-dose thiotepa and etoposide with autologous bone marrow rescue in children and young adults with recurrent CNS tumors. The Children's Cancer Group

PURPOSE

This study was designed to determine the toxicity, radiographic response rate, and outcome following high-dose thiotepa, etoposide, and autologous bone marrow rescue (ABMR) for young patients with recurrent malignant brain tumors.

METHODS

Eligibility criteria required adequate renal, hepatic, and pulmonary function, and no bone marrow infiltration. Thiotepa 300 mg/m2 and etoposide 500 mg/ m2 were infused on 3 consecutive days, and autologous bone marrow was infused 72 hours following chemotherapy.

RESULTS

Forty-five patients with recurrent high-grade brain tumors, aged 8 months to 36 years (median, 8 years), were treated. Seven patients (16%) died of treatment-related toxicities within 56 days of marrow reinfusion. Delayed platelet engraftment occurred in 44% of patients who survived beyond day 56. Of 35 patients with radiographically measurable disease who survived at least 28 days following ABMR, there were two complete responses (CRs) and six partial responses (PRs), for an overall response (CRs plus PRs) rate of 23% (SE = 7%). Objective responses were observed in four of 14 assessable patients with high-grade glioma and in two of six with primitive neuroectodermal tumors (PNETs)/ medulloblastoma. Survival was significantly improved in patients treated with minimal residual disease (P < .0005). Five of 18 patients (28%) with high-grade gliomas remain free of disease at 39+, 44+, 49+, 52+, and 59+ months post-ABMR.

CONCLUSION

The combination of high-dose thiotepa and etoposide has activity against a variety of recurrent childhood brain tumors. These results merit further evaluation in children and young adults with both recurrent and newly diagnosed high-grade brain tumors.

Phase II evaluation of topotecan for pediatric central nervous system tumors

BACKGROUND

Topotecan is a topoisomerase I inhibitor that has good penetration across the blood-brain barrier and significant antitumor activity against human brain tumor xenografts. In a Phase I trial in children with refractory cancer, topotecan was well tolerated when administered as a 24-hour infusion. The maximum tolerated dose was 5.5 mg/m2 and the dose-limiting toxicity was myelosuppression. This Phase II study of topotecan was performed to assess the activity of topotecan against childhood brain tumors.

METHODS

Forty-five children with either a previously treated primary brain tumor that was refractory to standard therapy, or an untreated brain stem glioma or glioblastoma multiforme, received topotecan administered as a 24-hour intravenous infusion every 21 days. The initial dose was 5.5 mg/m2 with escalation to 7.5 mg/m2 on the second and subsequent doses in patients who did not experience dose-limiting toxicity.

RESULTS

There were no complete or partial responses in the patients with high grade glioma (n=9), medulloblastoma (n=9), or brain stem glioma (n=14). One of 2 patients with a low grade glioma had a partial response lasting more than 17 months; 3 patients with a brain stem glioma had stable disease for 12 to 28 weeks; and 1 patient with a malignant neuroepithelial tumor and 1 patient with an optic glioma had stable disease for 41 weeks and 22 weeks, respectively. Dose escalation from 5.5 mg/m2 to 7.5 mg/m2 was well tolerated in the first 11 patients enrolled on this study who had not received prior craniospinal radiation therapy. The starting dose was subsequently increased to 7.5 mg/m2 for patients without prior craniospinal radiation.

CONCLUSIONS

Topotecan administered as a 24-hour infusion every 21 days is inactive in high grade gliomas, medulloblastomas, and brain stem tumors.

Central nervous system atypical teratoid/rhabdoid tumors of infancy and childhood: definition of an entity

Clinical and pathological features of 52 infants and children with atypical teratoid/rhabdoid tumor (ATT/RhT) of the central nervous system are defined. This tumor is typically misdiagnosed as a primitive neuroectodermal tumor (PNET) primarily because 70% of ATT/RhTs contain fields indistinguishable from classic PNETs. Separation of these two tumor types is crucial because the prognosis for ATT/RhT is given even when treatment includes surgery with or without radio and/or chemotherapy. These tumors are most common in infants less than 2 years of age. The cases described in this study arose in intracranially in all but one instance, although one-third had already spread throughout the subarachnoid space at presentation. Clinical signs and symptoms and radiological features do not distinguish ATT/RhTs from PNETs. The tumors are composed entirely (13%) or partly (77%) or rhabdoid cells. Seventy percent contains fields of typical PNET alone or in combinations with mesenchymal and/r epithelial elements. The immunohistochemical profile is unique: epithelial membrane antigen, vimentin, and smooth-muscle actin are positive in the majority of tumors and markers for germ-cell tumors are consistently negative. Abnormalities of chromosome 22 distinguish ATT/RhTs from PNETs, which typically display an i(17q) abnormality.

Chemotherapy for medulloblastomas and primitive neuroectodermal tumors

In the past two decades, chemotherapy has proven to be an increasingly more effective modality in the treatment of medulloblastoma. Current evidence suggests that chemotherapy be included as part of standard treatment for all patients with high-risk medulloblastoma. Ongoing multi-centre trials are determining whether chemotherapy should be added to reduced dose radiotherapy as a substitute therapy for standard-dose radiotherapy. The major randomized and non-randomized chemotherapy trials for newly diagnosed patients with medulloblastoma or for patients at recurrence are presented. It is hoped that the addition of chemotherapy will eventually lead to improved survival rates as well as the reduction in the craniospinal radiotherapy dose for patients with medulloblastoma.

Treatment of children with newly diagnosed brain stem gliomas with intravenous recombinant beta-interferon and hyperfractionated radiation therapy: a childrens cancer group phase I/II study

BACKGROUND

Prognosis for the majority of children with brain stem gliomas is dismal. In previous studies, recombinant beta-interferon (r beta IF) has been shown to be effective for children with recurrent brain stem gliomas and may also act synergistically with radiotherapy (RT).

METHODS

Thirty-two children with diffuse intrinsic brain stem gliomas were treated with (r beta IF) and 7200 centigray (cGy) of hyperfractionated RT (100 cGy twice-daily fractions) to determine the toxicity of treatment and the tolerance of the brain stem to this regimen, as well as to assess survival. Patients were treated with r beta IF 3 times per week during RT and then for 8 weeks following RT. Initially, a dose escalation trial was performed.

RESULTS

Interferon was initially begun at 12.5 x 10(6) IU/m2 and escalated up to 400 x 10(6) IU/m2. The safe starting dose was determined to be 100 x 10 (6) IU/m2. Due to unacceptable toxicity, the maintenance dose was reduced to 200 x 10 (6) IU/m2. Therapy was relatively well tolerated, although 13 of the patients required dose modifications due to hepatic or hematologic toxicity. Four of the patients had to discontinue treatment due to this toxicity. One patient died while receiving maintenance IF of encephalopathy, seizures, and brain stem dysfunction; believed possibly due to the r beta IF. Thirty of the 32 patients have developed progressive disease. The median time to progression from study entry was five months and the median time to death was 9 months.

CONCLUSIONS

We conclude that r beta IF plus hyperfractionated therapy can be tolerated by children with newly diagnosed brain stem gliomas, although there is occasional dose-limiting hepatic, blood, and central nervous system toxicity. This therapy did not result in a higher rate of disease control.

An integrated approach to the treatment of chiasmatic-hypothalamic gliomas

The treatment of visual pathway gliomas is controversial. The many retrospective studies reporting outcome data for patients with chiasmatic/hypothalamic gliomas are difficult to interpret for several reasons. First the natural history of these tumors is erratic with some reports suggesting that most visual pathway gliomas are hamartomas and follow an indolent course, and others reporting 10-year survival rates of close to 60%. Second, earlier studies did not clearly indicate which patients had neurofibromatosis type 1 (NF1) and recent evidence suggests that the natural history of optic gliomas is more favorable in patients with NF1. Third the methods and accuracy of diagnosis have changed dramatically and patients diagnosed before and after the advent of CT/MR imaging have often been included in the same series. While surgical resection is usually not a viable option for definitive treatment of these tumors, recent studies have shown favorable results after subtotal resection in selected patients. The efficacy of radiotherapy has not been unequivocally demonstrated and treatment-related morbidity has become a major concern, in particular, adverse effects on cognition and growth. Chemotherapy has been advanced as an viable alternative to avoid or delay the adverse affects of RT, but the long-term outcome benefits and adverse effects of treatment are just being defined. Despite the limitations of currently available information, sufficient data are now available to rational management quotelines for the majority of children with chiasmatic/hypothalamic gliomas.

Updated results of a pilot study of low dose craniospinal irradiation plus chemotherapy for children under five with cerebellar primitive neuroectodermal tumors (medulloblastoma)

PURPOSE

Children under 5 years old with medulloblastoma (MB) have a poor prognosis. They are more susceptible to the deleterious effects of craniospinal irradiation (CSART) and have a higher relapse rate when treated with low-dose CSART alone. We, thus, embarked on a prospective trial testing the usefulness of very low dose CSART and adjuvant chemotherapy. This is an update of a previous report on these patients.

METHODS AND MATERIALS

Between January 1988 and March 1990, 10 patients with medulloblastoma were treated using 18 Gy radiation therapy (RT) to the craniospinal axis, a posterior fossa (PF) boost to 50.4-55.8 Gy and chemotherapy consisting of vincristine (VCR) weekly during RT. This was followed by VCR, cis-diamminedichloroplatinum (CDDP), and lomustine (CCNU) for eight, 6-week cycles. Patients between 18 and 60 months of age without evidence of tumor dissemination were eligible for study. Follow-up was available until September 1994 with a median follow-up for living patients of 6.3 years from diagnosis.

RESULTS

Actuarial survival at over 6 years is 70 +/- 20%. Three of the 10 patients relapsed and died. In one patient, the relapse developed in the spine and brain outside the posterior fossa, in the second, concurrently in the posterior fossa, brain and spine, and the third, only in the spine. One surviving child developed a brain stem infarct 4.8 years after diagnosis and has since almost fully recovered. A mean intelligence quotient (IQ) score of 103 in six patients surviving at least 1 year is unchanged from the baseline group score of 107. Five children tested at baseline and 2 years following treatment had IQ scores of 101 and 102, respectively. Six children tested at baseline and at 3 years had IQ scores of 106 and 96, respectively. Excluding the child tested shortly after his brain stem infarct, baseline and 3 year IQ scores were 103 and 97, respectively. Five of the seven long-term survivors grew at rates significantly below their expected velocities during the follow-up period, while the others grew normally. Three patients have received growth hormone, and none have required thyroid replacement.

CONCLUSIONS

These data suggest that medulloblastoma patients can be cured with chemotherapy and reduced doses of craniospinal irradiation. The low doses of CSART given by us in conjunction with cis-platin-based chemotherapy produce minimal neurocognitive damage. Growth velocities in very young children so treated are, however, dramatically reduced. Better means of improving the therapeutic ratio are still needed.

Brain stem gliomas: therapeutic options at time of recurrence

Despite contentions to the contrary, the majority of children with recurrent brain stem gliomas survive for at least 3 months after first relapse. Treatment can be undertaken and response determined, especially if brain stem necrosis is taken into consideration. Relatively few patients have been treated on well-designed studies accruing adequate numbers of patients. No conventional salvage therapy exists. Adequate studies with innovation approaches are needed to help individual patients, families and future generations of children with brain stem gliomas.

Alternative therapies for children with brain stem gliomas: immunotherapy and gene therapy

Alternative means are needed for the treatment of childhood brain stem gliomas. Both immunotherapy and gene therapy have and will be, in the future, evaluated for these patients. Results, to date, with immunotherapy have been sparse and variable. Restorative immunotherapy, especially the use of beta-interferon, has shown some promising results. However, in one recently completed trial, the combination of beta-interferon plus hyperfractionated radiotherapy in newly diagnosed patients did not apparently result in improved survival. Gene therapy, still in its infancy, also may be potentially applicable to the treatment of children with brain stem gliomas.

Results of a prospective randomized trial comparing standard dose neuraxis irradiation (3,600 cGy/20) with reduced neuraxis irradiation (2,340 cGy/13) in patients with low-stage medulloblastoma. A Combined Children's Cancer Group-Pediatric Oncology Group Study

PURPOSE

To determine in a prospective randomized trial the effect on survival, progression-free survival, and patterns of relapse of a decrease in the neuraxis radiation dose from 3,600 cGy in 20 fractions to 2,340 cGy in 13 fractions in patients with newly diagnosed medulloblastoma between 3 and 21 years of age with low T stage (T1, T2 and T3A), minimal postoperative residual tumor, and no evidence of dissemination (M0).

METHODS AND MATERIALS

Between June 1986 and November 1990, the Children's Cancer Group and the Pediatric Oncology Group randomized 126 patients in a two-arm study comparing the two different doses of neuraxis irradiation. In both arms, the posterior fossa received 5,400 cGy in 30 fractions. All patients were staged with myelography, postoperative lumbar cerebrospinal fluid cytology, and postoperative contrast-enhanced cranial computerized tomography to ensure no evidence of dissemination and no more than 1.5 cm3 residual tumor volume. Overall survival, progression-free survival, and patterns of recurrence were carefully monitored. Prospective endocrine and psychometric studies were performed to determine the benefit of decreasing the neuraxis radiation dose.

RESULTS

Following an interim analysis at a median time on study of 16 months, the study was closed, since a statistically significant increase was observed in the number of all relapses as well as isolated neuraxis relapses in patients randomized to the lower dose of neuraxis radiation.

CONCLUSIONS

In patients with newly diagnosed medulloblastoma considered to have a good prognosis on the basis of low T stage, minimal residual tumor after at least subtotal resection, and no evidence of dissemination after thorough evaluation, there is an increased risk of early relapse associated with lowering the dose of neuraxis radiation from 3,600 cGy in 20 fractions to 2,340 cGy in 13 fractions.

Brainstem gliomas in children. A Children's Cancer Group review of 119 cases

Brainstem gliomas (BSG) with intrinsic and extensive brainstem involvement continue to have a poor outlook despite current treatment approaches. Neuroimaging studies have aided in the differentiation of malignant brainstem tumors from more 'benign' subgroups. A Children's Cancer Group protocol evaluating outcome in children with BSG after treatment with hyperfractionated radiotherapy (7,200-7,800 cGy) was recently completed. The clinical aspects of 119 children entered into this study were reviewed in an attempt to determine risk groups and prognostic indicators. The overall survival of this group was very poor and there was no statistically significant correlation of survival with age, sex, clinical symptoms and signs, or tumor grade. Longer survival was only associated with prolonged duration of brainstem symptoms and signs greater than 1 month prior to diagnosis of the tumor. Improved outlook for children with BSG will require further research in tumor biology and newer therapeutic modalities.

Long-term outcome of hypothalamic/chiasmatic astrocytomas in children treated with conservative surgery

The feasibility of radical surgery for astrocytomas of the optic chiasm/hypothalamus has been reported by several groups. Such surgery carries significant risks, however, including permanent damage to the pituitary gland, optic apparatus, hypothalamic structures, and carotid arteries. The benefits of radical surgery, both in terms of efficacy and toxicity, should, therefore, be evaluated against standard therapy, as is usually done for new chemotherapeutic protocols. To this end, a retrospective review was performed of 33 patients treated at Children's Hospital of Philadelphia between 1976 and 1991 who met criteria that would have made them eligible for radical surgery in many centers today, but were treated with either no surgery or conservative surgery (< 50% resection) or biopsy followed by adjuvant therapy with local radiation therapy (29 patients) and/or chemotherapy with actinomycin-D and vincristine (18 patients). The review encompassed all children with a globular enhancing mass of at least 2 cm in the hypothalamic/chiasmatic region, no evidence of optic nerve involvement or involvement of the optic radiations by computerized tomography or magnetic resonance imaging, and follow up of at least 3 years. All but one patient had tissue confirmation of a low-grade or pilocytic astrocytoma. Thirteen of the patients were 2 years of age or younger at diagnosis. Five individuals died: three of tumor progression, one of acute shunt malfunction, and one of intercurrent infection. The remaining 28 were alive at last follow up, a mean of 10.9 years from diagnosis. Twenty-three surviving patients have functional vision in at least one eye, 12 require no endocrine replacement, and 16 are in or have completed schooling with regular academic requirements. If radical surgery is to become standard care for children with low-grade astrocytomas of the hypothalamic/chiasmatic region, long-term survival and functional outcome will have to equal or surpass those of historical controls who were treated conservatively.

'Complicated migraine-like episodes' in children following cranial irradiation and chemotherapy

Neurologic sequelae may occur months to years after cranial irradiation. The site of primary damage is probably the vascular endothelium. Over a 2.8-year period, four children with brain tumors, a mean of 11 years of age at diagnosis (range, 6.5 to 15.5 years), had new onset of severe intermittent unilateral headaches associated with nausea, episodic visual loss, hemiparesis, aphasia, or hemisensory loss. The headaches lasted 2 to 24 hours. All patients had previously received whole-brain (2,400 to 3,600 cGy) and additional local boost (1,800 to 3,100 cGy) cranial irradiation, as well as cisplatin-, lomustine-, and vincristine-containing chemotherapy regimens. Symptoms began 1.2 to 2.8 years after the diagnosis, when all had stable disease and were off treatment. MRI studies were unchanged, and CSF cytology, EEGs, echocardiograms, and magnetic resonance angiograms were normal in all. Cerebral angiograms, performed in three children, were normal but led to severe headaches and neurologic deficits (hemiparesis in one and visual loss in two) that resolved after 24 to 48 hours. Response to antimigraine and antiplatelet medications was variable. We conclude that (1) "complicated migraine-like episodes" may occur in children after cranial irradiation and chemotherapy as a sequela of therapy; (2) these headaches may not be the harbinger of impending strokes, severe intracranial vasculitis, or tumor recurrence; and (3) while cerebral angiography may be useful in differential diagnosis, it may cause transient worsening of symptoms.

Encephalopathy with parkinsonian features in children following bone marrow transplantations and high-dose amphotericin B

Encephalopathy, leukoencephalopathy, and secondary parkinsonism occurred in 3 children with refractory leukemia undergoing allogenic bone marrow transplantation (BMT) who were treated with high-dose amphotericin B for pulmonary aspergillosis or sinus aspergillosis that did not involve the nervous system. Treatment included high-dose cytosine arabinoside, cyclophosphamide, and total body irradiation prior to the BMT. The children developed a progressively worsening encephalopathy and parkinsonian features, characterized by resting tremor, cogwheel rigidity, and masklike facies. Neuroimaging studies showed cerebellar, cerebral, and basal ganglia atrophy, as well as frontal and temporal lobe white matter involvement. Two of the 3 patients recovered, although 1 has residual intellectual impairment. The third succumbed to non-central nervous system Epstein-Barr virus-lymphoproliferative disease and had autopsy-confirmed leukoenephalopathy.

A phase I and II trial of dose-intensified cyclophosphamide and GM-CSF in pediatric malignant brain tumors

PURPOSE

Cyclophosphamide is commonly used in the treatment of children with malignant brain tumors. The purpose of this study was to develop a multicycle, high-dose intensity cyclophosphamide regimen with granulocyte-macrophage colony-stimulating factor (GM-CSF) and to assess its activity against malignant glioma and primitive neuroectodermal tumor (PNET).

METHODS

Twenty-three patients with brain tumors, including 15 with malignant glioma and six with PNET, were enrolled. Cyclophosphamide (1.8-2.25 g/m2/day for 2 days i.v.; total dose 3.6-4.5 g/m2) was administered and was followed by recombinant human GM-CSF (5 micrograms/kg/day s.c.) on days 3-11 or until the absolute granulocyte count reached 1.5 x 10(9)/L.

RESULTS

With a total of 83 cycles administered, the mean dose intensity of cyclophosphamide ranged from 1.5 g/m2/week through cycle 2 (22 patients) to 0.8 g/m2/week through cycle 8 (two patients). No activity was seen against malignant glioma, and five of six patients with PNET had partial responses. The mean duration of a neutrophil count of < 0.5 x 10(9)/L was only 8 days; the platelet recovery was substantially longer. Fever during neutropenia occurred in 54 of 83 cycles. One patient died from transfusion-related graft-versus-host disease.

CONCLUSIONS

A cyclophosphamide regimen equal to twice the dose intensity of that used in conventional therapy was administered. The regimen was active against PNET but inactive against malignant glioma.

Optic pathway and hypothalamic/chiasmatic gliomas in children younger than age 5 years with a 6-year follow-up

BACKGROUND

Gliomas of the hypothalamus and optic pathways (H/OPG) comprise 5% of pediatric intracranial tumors, present most frequently in patients younger than age 5 years, and may have a more aggressive course in younger children. This study examined clinical characteristics and consequences of treatment of young children diagnosed with H/OPG:

METHODS

The authors reviewed the course, treatment, and outcomes of 46 children diagnosed with H/OPG younger than age 5 years; the median follow-up was 72 months. The median age at diagnosis was 27 months.

RESULTS

Fifteen (33%) of 46 patients had neurofibromatosis-1 (NF-1). Forty children (87%) had tumor progression in the follow-up period, and tumor growth was less common in children with NF-1. Initial therapy was limited to surgical resection in three and radiation in five children. To postpone radiation until after the age of 5 years, initial therapy was limited to chemotherapy in 32 patients. Radiation was not required in 9 of these patients and was postponed for 40 months (mean) in 17. Of the 46 children, 5 died of tumor progression, 4 became blind, and 20 of 34 evaluable patients had endocrine abnormalities. Endocrinopathy did not correlate with therapy. Ten of 17 children evaluated by questionnaire required special education. There was a trend for educational problems to occur in children who were irradiated before the age of 5 years.

CONCLUSIONS

Gliomas of the hypothalamus and optic pathways and their treatment cause long term morbidity in young children. Chemotherapy postpones radiation effectively, and this delay may reduce neurologic morbidity; however, 60% of children eventually relapse. By contrast, patients with NF-1 have indolent disease.

Survival of infants with malignant astrocytomas. A Report from the Childrens Cancer Group

BACKGROUND

Very young children with central nervous system malignant brain tumors have a poor prognosis. As compared with older children, survival is less likely, and those children who do survive frequently have severe impairment of growth and cognitive abilities, resulting partly from treatment with radiotherapy. Therefore, an intensive chemotherapeutic regimen was used to treat children younger than 2 years of age with a diagnosis of malignant astrocytomas.

PATIENTS AND METHODS

Thirty-nine children younger than 24 months of age who were diagnosed with malignant astrocytoma were treated on a Childrens Cancer Group protocol with an eight-drug chemotherapeutic regimen (vincristine, carmustine, procarbazine, hydroxyurea, cisplatin, cytosine arabinoside, prednisone, and dimethyl-triazenoimidazole-carboxamide) after surgery and postoperative staging. Radiation therapy was to be deferred until the completion of chemotherapy.

RESULTS

The objective response rate after two cycles of chemotherapy was 24%. Most patients did not receive radiotherapy. Progression-free survival (PFS) and survival at 3 years was 36% (standard error, 8%) and 51% (8%), respectively. The PFS of those children with anaplastic astrocytoma was 44% (11%), significantly better than that of glioblastoma multiforme (GBM) (0%). Extent of resection was not associated significantly with PFS, but tumors within the cerebral hemispheres were associated with a more favorable prognosis. Tumor progression occurred locally in almost all cases and early in treatment (median PFS, 8 months).

CONCLUSION

Chemotherapy appears to be effective primary adjuvant treatment for some very young children with anaplastic astrocytomas. Overall, however, survival remains poor, especially for children with GBM. Strategies to improve outcome require early intervention, because tumor progression occurs soon after diagnosis in the majority of patients.

Brain tumors in children

Brain tumors are the most common form of solid neoplasm of childhood. Progress in the treatment of childhood brain tumors has been frustratingly slow, especially in comparison with other pediatric malignancies. The biology of primary pediatric brain tumors of childhood is just being unraveled. Chemotherapy is a major component of the treatment of many forms of childhood primary central nervous system tumors and is being used in attempts to improve survival and to delay or decrease the amount of radiotherapy needed. Despite the use of more aggressive radiotherapy approaches and intensified chemotherapy approaches, outcome remains dismal for brain stem gliomas and high-grade cortical gliomas. Many unsettled issues exist concerning the treatment of childhood low-grade gliomas.

Diagnosis and treatment of pediatric brain tumors

Brain tumors are the most common form of solid neoplasm of childhood. Progress is clearly being made in the understanding and management of childhood brain tumors. There are possible biologic differences between histologically similar childhood and adult brain tumors. Chemotherapy is a major component of the treatment of many forms of childhood primary central nervous system tumors and is being used in attempts to improve survival and to delay or decrease the amount of radiotherapy needed. Despite the use of more aggressive radiotherapy approaches or intensified chemotherapy approaches, the outcome remains dismal for some forms of brain cancer. Many unsettled issues exist concerning the management of childhood low-grade gliomas.

Outcome for children with medulloblastoma treated with radiation and cisplatin, CCNU, and vincristine chemotherapy

It has previously been reported in a single-institution trial that progression-free survival of children with medulloblastoma treated with radiotherapy and 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU), cisplatin, and vincristine chemotherapy during and after radiotherapy was better than the outcome in children treated with radiotherapy alone. To better characterize long-term outcome and duration of disease control, this treatment approach was used for 10 years and expanded to three institutions. Sixty-three children with posterior fossa medulloblastomas were treated with craniospinal local-boost radiotherapy and adjuvant chemotherapy with vincristine weekly during radiotherapy followed by eight 6-week cycles of cisplatin, CCNU, and vincristine. To be eligible for study entry, patients had to be older than 18 months of age at diagnosis and have a subtotal resection, evidence of metastatic disease, and/or brainstem involvement. Patients younger than 5 years of age and without these poor risk factors who received reduced-dose craniospinal radiotherapy (2400 cGy) were also eligible for entry into the study. Sixty-three of 66 eligible patients (95%) were entered and placed on this treatment regimen. Forty-two patients had brainstem involvement, 15 had metastatic disease at the time of diagnosis, and 19 had received a subtotal resection. Progression-free survival for the entire group at 5 years is 85% +/- 6%. Three children have succumbed to a second malignancy, and overall 5-year event-free survival is 83% +/- 6%. Progression-free survival was not adversely affected by younger age at diagnosis, brainstem involvement, or subtotal resection. Five-year actuarial progression-free survival for patients who received reduced-dose radiotherapy was similar to that for patients receiving conventional-dose radiotherapy. Patients with metastatic disease at the time of diagnosis had a 5-year progression-free survival rate of 67% +/- 15%, as compared to 90% +/- 6% for those patients with localized disease at the time of diagnosis (p = 0.037). The authors conclude that overall progression-free survival remains excellent for children with posterior fossa medulloblastomas treated with this drug regimen. Chemotherapy has a definite role in the management of children with medulloblastoma. Further studies are indicated to define which subpopulations of children with medulloblastoma benefit from chemotherapy and what regimens are optimum in increasing disease control and, possibly, in reducing the amount of radiotherapy required.

Outcome of children with brain stem gliomas after treatment with 7800 cGy of hyperfractionated radiotherapy. A Childrens Cancer Group Phase I/II Trial

BACKGROUND

Brain stem gliomas remain the childhood brain tumors most resistant to treatment. Treatments with hyperfractionated radiotherapy at doses as high as 7560 cGy have been fairly well tolerated. This study was undertaken to determine the toxicity and possible efficacy of hyperfractionated radiotherapy in children with brain stem gliomas using 100 cGy of radiation twice daily, to a total dose of 7800 cGy.

METHODS

Sixty-six children (mean age at diagnosis, 7.5 years) with diffuse intrinsic brain stem gliomas were treated. Patients were evaluated for potential toxicity of treatment, progression-free survival, survival, and response to treatment.

RESULTS

Objective response to treatment was documented in 20 of 58 (34%) evaluable patients, with 8 (14%) patients having a greater than 50% reduction in tumor size. Overall survival was 35% plus or minus 6% at 1 year and 11% plus or minus 6% at 3 years. Intralesional cystic/necrotic radiographic changes developed in nine patients 6 weeks after radiation, and three of these patients subsequently improved without antitumor intervention. Six of 14 autopsied patients had evidence of probable radiation-induced intralesional necrotic damage, and in 1, necrosis may have played a role in death. Thirty-three of 66 patients were treated with steroids for prolonged periods.

CONCLUSIONS

The results of this treatment regimen demonstrate that hyperfractionated radiotherapy, as delivered in this study to a total dose of 7800 cGy, is relatively well tolerated, but may result in prolonged steroid-use dependency and possible radiation-associated damage. Objective responses to treatment were seen in 34% of patients, but these results were not better than those seen at lower doses of hyperfractionated radiotherapy. There is no evidence that radiation to 7800 cGy results in improved survival for patients with diffuse intrinsic brain stem gliomas.

Quality of long-term survival in young children with medulloblastoma

The reported success of treatment for children with medulloblastoma must be balanced against the effect that treatment has on the quality of life of long-term survivors. The outcome of long-term survivors reported in previous studies has been conflicting. The authors evaluate the mental and behavioral skills of a group of medulloblastoma survivors from their institution, all of whom had survived for more than 5 years postdiagnosis. A review of the institutional records yielded 32 patients. Twenty-three families were interviewed by telephone and, of these, 13 subjects came to the hospital for detailed neuropsychological and neurological evaluations. Intelligence quotient (IQ) was less than 90 for all participants tested, and patients diagnosed before the age of 3 years had lower IQ scores on average than those diagnosed later. Mean IQ and achievement test scores in reading, spelling, and mathematics were all higher in survivors who had undergone shunting. Achievement test results were often not in accord with intellectual potential, and individual intellectual skills varied widely. Perceptual-motor task performance was below average in more than 50% of the participants, but motor dexterity was more severely affected than perception. Problems in learning and a delay in both physical growth and development were seen in a majority of participants. This study directs attention to the serious difficulties faced by long-term survivors of medulloblastoma and their families, and underscores the importance of routine neuropsychological testing. Moreover, the study provides further impetus to seek alternatives to irradiation in the treatment of malignant brain tumors.

Seizure control following tumor surgery for childhood cortical low-grade gliomas

Detailed preoperative electroencephalographic (EEG) studies are now recommended for children with seizures and cortical tumors to define seizure foci prior to surgery. To develop a historical perspective for better evaluation of results from series reporting tumor removal combined with resection of seizure foci, the authors reviewed seizure outcome in 60 children with seizures and low-grade neoplasms treated consecutively since 1981 by surgical resection without concomitant EEG monitoring or electrocortical mapping. Forty-seven of the 60 tumors were totally or near-totally resected; 45 patients were seizure-free and two were significantly improved 1 year following surgery. Of the 50 children in this series with more than five seizures prior to surgery, 36 were seizure-free, two were significantly improved, and 12 were not improved. Factors associated with poor seizure control included a parietal tumor location, a partial tumor resection, and a history of seizures for more than 1 year prior to surgery. The children at highest risk for poor seizure control at 2 years had experienced seizures for more than 1 year prior to surgery and had undergone partial resection of their parietal low-grade glial tumors or gangliogliomas. In contradistinction, the best seizure control was seen in patients with totally resected low-grade gliomas or gangliogliomas who had experienced seizures for less than 1 year (concordance rates for being seizure-free ranged from 78% to 86%). Long-term seizure control remained excellent. These results suggest that seizure control can be obtained 2 years following tumor surgery in the majority of children with presumed tumors after extensive tumor resection without concomitant EEG monitoring or electrocortical mapping.

Diagnosis, treatment, and outcome of primary central nervous system tumors of childhood

Significant work has been published over the past year on the management of childhood primary central nervous system tumors. Chemotherapy is taking on an increased role in the treatment of children with medulloblastoma and low-grade gliomas and infants with malignant tumors. Although survival remains poor for children with brain stem gliomas, even after treatment with high-dose radiotherapy regimens, subsets of patients have been identified who have a more favorable prognosis. Neurocognitive dysfunction remains a significant treatment outcome in children surviving brain tumors.

Infratentorial brain tumors of childhood

One half of brain tumors in children originate in the posterior fossa. Although a wide variety of lesions occurs, four tumor types account for more than 95% of cases. Knowledge of their modes of presentation, CT and MR features, and pattern of spread can usually lead to a correct diagnosis.

Neurologic manifestations of cocaine exposure in childhood

OBJECTIVE

To describe the neurologic manifestations of cocaine exposure in children and adolescents as the neurologic effects of cocaine have been described in adults and neonates.

METHODS

During 1-year period, 41 children between the ages of 2 months and 18 years who had been exposed to cocaine, were examined in the emergency department at the Children's National Medical Center. Cocaine exposure was documented on urine samples; all were confirmed by urine gas chromatographic/mass spectrometric analysis.

RESULTS

Nineteen (46%) of 41 had neurologic abnormalities, including seizures (7), obtundation (6), delirium (4), dizziness (1), drooling (1), and ataxia (1). In 14 others, the neurologic effects of cocaine were difficult to determine because of other concomitant medical conditions, including head injuries and severe abdominal or chest trauma. Two major age-related patterns were seen: (a) in each child < 5 years of age, seizures and obtundation; and (b) in 11 older children, delirium (3), dizziness (1), drooling (2), and lethargy (4). Seizures, occurring at ages 12 months to 8 years, were focal with secondary generalization in three and generalized in four. They were associated with fever in two children. Six children had no further seizures, and one developed a mixed-seizure disorder. Passive intoxication while being in a room in which "crack" was smoked was the most likely cause of exposure for young victims. Multiple drug abuse was not documented in any child with neurologic impairment.

CONCLUSIONS

1) Cocaine exposure is common in children in our urban setting; 2) neurologic manifestations frequently occur; 3) in children 8 years of age or younger, "passive" ingestion/inhalation is associated with focal and generalized seizures without evidence of structural brain injury; 4) cocaine may lower seizure threshold in children predisposed to seizures; 5) in children > 8 years of age, manifestations are similar to those in adults; 6) trauma and motor vehicle accidents were seen in the adolescent age group exposed to cocaine; and 7) urine toxicological study in cocaine exposure is recommended in all first-time seizures as well as first-time febrile seizures.

Staging and surveillance of children with central nervous system neoplasms: recommendations of the Neurology and Tumor Imaging Committees of the Children's Cancer Group

Standardization of the baseline and surveillance evaluation of children with central nervous system (CNS) tumors could contribute to understanding tumor behavior, establishing prognoses, directing treatment, and interpreting multi-institutional cooperative study data. A tumor categorization schedule, based on recognized patterns of CNS tumor behavior involving 'aggressiveness' as assessed by the likelihood for neuraxis dissemination, relative time to progression and pattern of disease recurrence is presented. Included are the most common histologic subtypes of pediatric CNS neoplasms. No attempt has been made to include all histologic subtypes of pediatric CNS neoplasms. Using this categorization as a framework, recommendations are suggested for baseline evaluation at diagnosis and in surveillance.

Pre-irradiation chemotherapy in children with high-grade astrocytoma: tumor response to two cycles of the '8-drugs-in-1-day' regimen. A Childrens Cancer Group study, CCG-945

PURPOSE

This study was undertaken to evaluate the radiographic response to two cycles of chemotherapy prior to irradiation in newly diagnosed children with high-grade astrocytomas.

PATIENTS AND METHODS

One hundred and thirty children less than 21 years of age with newly-diagnosed high-grade astrocytoma were treated with the 'eight-drugs-in-one-day' chemotherapy regimen as part of a phase III multi-institutional Childrens Cancer Group (CCG) trial. Computerized Tomographic (CT) or Magnetic Resonance Image (MRI) scans, obtained after two cycles of chemotherapy had been administered, were compared with post-operative scans to determine treatment response. Scans were evaluated by institutional radiologists, and were reviewed centrally by a single neuroradiologist.

RESULTS

Of 79 patients with evaluable post-operative residual tumor on CT or MRI scans, 26 (33%) were determined on institutional evaluation to have had an objective response. However, central review of scans documented responses on only 14/79 (18%). A significantly higher response rate on central review was observed for those children 36 months of age or less at study entry than for older children (33% v 11%; p < 0.001). However, a higher disease progression rate was also observed for those children 36 months of age or less than for older children (21% v 2.6%; p < 0.001).

CONCLUSION

In this study, the largest yet reported in newly-diagnosed children with high-grade astrocytomas, the chemotherapy regimen has activity in younger children. The differences in response rates reported by institutional and central review highlight the difficulties inherent in assessing response to brain tumor therapy. However, the study does demonstrate the consistent ability of radiologists to identify disease progression within the institutional and central reviews.

Magnetic resonance scans should replace biopsies for the diagnosis of diffuse brain stem gliomas: a report from the Children's Cancer Group

Children's Cancer Group Protocol CCG-9882 was designed to determine the effectiveness of hyperfractionated radiation for the treatment of children and young adults with brain stem gliomas. The study opened for the accrual of patients on September 21, 1988, and was closed on June 30, 1991. The first 54 children in the study were treated with irradiation doses of 100 cGy given twice daily to a total dosage of 7200 cGy. The next 66 children were treated with a similar daily regimens to a total of 7800 cGy. Tumors were diagnosed by clinical and radiographic criteria. Decisions about the need for surgery were left to the discretion of the treating neurosurgeon; tissue diagnosis did not alter the therapy in patients with diffuse infiltrating tumors. We reviewed the neuroradiology and neurosurgery reports as well as the pathological specimens of children entered on the study. By magnetic resonance (MR) imaging criteria, tumors involved the majority of the brain stem in 76% of cases; only three patients had tumors localized to the midbrain or medulla. Operations were performed on 56 of 120 patients (47%). Cerebrospinal fluid shunts were inserted in 27 (23%) of the children; insertion of a shunt was the only operation in 11, and a shunt was inserted in conjunction with a tumor operation in 16. Tumor operations were performed in 45 (38%) of the patients; 24 had stereotactic biopsies, and 21 had craniotomies. Of the 21 patients who had craniotomies, only biopsies were performed in 11; partial tumor resections were performed in 5 patients and subtotal resection in 5.(ABSTRACT TRUNCATED AT 250 WORDS)

Hyperfractionated radiation therapy (72 Gy) for children with brain stem gliomas. A Childrens Cancer Group Phase I/II Trial

BACKGROUND

Most children with brain stem gliomas (BSG) die within 18 months of diagnosis. Early experience suggested that hyperfractionated radiation therapy (RT) at a dose of 72 Gy, administered in 1-Gy fractions twice daily, possibly improved disease-free survival for children with BSG.

METHODS

To better characterize the toxicity and possible efficacy of this dose and fractionation of RT, 53 assessable children with diffuse intrinsic or malignant BSG were treated. Survival figures also were combined with outcome in 36 patients treated in a previous pilot study.

RESULTS

An objective response to treatment was observed in 28 of 53 (53%) patients; a partial response occurred in 7. No child died of treatment-related brain necrosis, although 7 of 53 did have intralesional cystic/necrotic changes within 6 weeks of completion of RT. The overall survival rate for patients in the study was 38% (+/- 6.5) at 1 year, 14% (+/- 5.4) at 2 years, and 8% (+/- 6.5) at 3 years. Leptomeningeal dissemination was observed in 4 of 48 (8%) children who had relapses. A greater than 2-month duration of symptoms before diagnosis was related to a better prognosis. There was no statistical association between any other clinical parameter, neuroradiographic finding, or pathologic finding and outcome. Combined with that in 35 patients treated in the pilot study, the survival rate in 88 children was 14% (+/- 5) at 3 years.

CONCLUSIONS

The radiographic response rate is encouraging; however, it cannot be concluded that hyperfractionated RT, at this dose schedule and total dose, is superior to conventional RT.

Brain tumors in children under 2 years: treatment, survival and long-term prognosis

Survival for children with brain tumors less than 2 years of age at diagnosis is dismal, and the quality of life of long-term survivors poor. Between 1975 and 1987, 78 (13%) of 579 patients with brain tumors treated at Children's Hospital of Philadelphia were under 2 years of age. Tumor site was posterior fossa in 31 (40%) and supratentorial in 47 (60%). Nine of 37 patients (24%) with malignant tumors, and 30 of 41 (73%) patients with benign tumors are alive with a mean follow-up of 116 months. Long-term survival after treatment with chemotherapy alone occurred in 10 patients, including 3 with malignant tumors. In 5 additional patients, chemotherapy delayed the need for irradiation a mean of 30 months. Of the 29 patients who relapsed after initial therapy, 12 are alive without progressive disease (2 patients with malignant tumors and 10 with benign tumors) a mean of 80 months after relapse, 2 children are alive with progressive disease, and 14 died a median of 48 months (range 9-115 months) after relapse. Twenty-one of the 39 survivors have minimal or no neurological or intellectual dysfunction. Surviving patients treated with surgery and chemotherapy have better intellectual function than patients treated with surgery and radiation (with or without chemotherapy) in that 8 of 10 children treated with surgery and chemotherapy have normal or above normal intelligence compared with 5 of 12 children receiving irradiation before their second birthday.

A phase II evaluation of thiotepa in pediatric central nervous system malignancies

BACKGROUND

Both thiotepa and its active metabolite, tepa, efficiently cross the blood-brain barrier. After intravenous administration, the cerebrospinal fluid concentrations achieved are nearly identical to those in plasma. This provides a strong rationale for testing this agent against brain tumors.

METHODS

Sixty pediatric patients with recurrent primary brain tumors were treated on a multiinstitutional Phase II study of intravenous thiotepa at a dose of 65 mg/m2 administered every 3 weeks. This dose is the result of a prior pediatric Phase I trial and is significantly higher than those previously recommended.

RESULTS

Three of 13 assessable patients with medulloblastoma had partial responses lasting 22, 25, and 54 weeks. Although no objective responses were observed in 16 assessable patients with malignant gliomas and 14 with brain stem gliomas, 5 of 16 and 4 of 14 patients in these respective strata had prolonged periods of stable disease (SD) lasting from 12 to more than 33 weeks. Nine assessable patients with ependymoma had no objective response, but two had SD, both for more than 33 weeks. Myelosuppression was the principle toxic effect encountered and appeared to be more severe in patients who had received prior craniospinal radiation therapy or nitrosourea therapy.

CONCLUSIONS

By conventional Phase II criteria, thiotepa appears to have activity in medulloblastoma. Based on several patients with prolonged SD, it also may possess some limited activity in brain stem and malignant gliomas. The steep in vitro dose-response curve of thiotepa and the long durations of response or SD observed with the dose reported here suggest that moderate-dose to high-dose thiotepa with cytokine support or autologous bone marrow rescue may be associated with an improved response rate to this agent.