Low-stage medulloblastoma: final analysis of trial comparing standard-dose with reduced-dose neuraxis irradiation

PURPOSE

To evaluate prospectively the effects on survival, relapse-free survival, and patterns of relapse of reduced-dose (23.4 Gy in 13 fractions) compared with standard-dose (36 Gy in 20 fractions) neuraxis irradiation in patients 3 to 21 years of age with low-stage medulloblastoma, minimal postoperative residual disease, and no evidence of neuraxis disease.

PATIENTS AND METHODS

The Pediatric Oncology Group and Children's Cancer Group randomized 126 patients to the study. All patients received posterior fossa irradiation to a total dose of 54 Gy in addition to the neuraxis treatment. Patients were staged postoperatively with contrast-enhanced cranial computed tomography, myelography, and CSF cytology. Of the registered patients, 38 were ineligible.

RESULTS

The planned interim analysis that resulted in closure of the protocol showed that patients randomized to the reduced neuraxis treatment had increased frequency of relapse. In the final analysis, eligible patients receiving standard-dose neuraxis irradiation had 67% event-free survival (EFS) at 5 years (SE = 7.4%), whereas eligible patients receiving reduced-dose neuraxis irradiation had 52% event-free survival at 5 years (SE = 7.7%) (P =.080). At 8 years, the respective EFS proportions were also 67% (SE = 8.8%) and 52% (SE = 11%) (P =.141). These data confirm the original one-sided conclusions but suggest that differences are less marked with time.

CONCLUSION

Reduced-dose neuraxis irradiation (23.4 Gy) is associated with increased risk of early relapse, early isolated neuraxis relapse, and lower 5-year EFS and overall survival than standard irradiation (36 Gy). The 5-year EFS for patients receiving standard-dose irradiation is suboptimal, and improved techniques and/or therapies are needed to improve ultimate outcome. Chemotherapy may contribute to this improvement.

Silent lacunar lesions detected by magnetic resonance imaging of children with brain tumors: a late sequela of therapy

BACKGROUND

Cerebral lacunes, which generally appear on magnetic resonance imaging as foci of white matter loss, usually occur in adults after ischemic infarcts. We report the development of lacunes in children after therapy for brain tumors.

PATIENTS AND METHODS

We reviewed the clinical characteristics and radiologic studies of 524 consecutive children with brain tumors treated over a 10-year period. We documented the neuropsychologic findings associated with lacunes and the factors predictive of lacunar development.

RESULTS

Lacunes developed in none of the 103 patients observed or treated with surgery alone. Twenty-five of the 421 patients treated with chemotherapy or radiation therapy or both had lacunes. Patients were a median of 4.5 years old at the time of both diagnosis (range, 0.3 to 19.8 years) and radiotherapy (range, 1.5 to 20 years). Fourteen patients were treated with craniospinal irradiation, and 11 were treated with local radiotherapy. The median time from radiotherapy to the appearance of lacunes was 2.01 years (range, 0.26 to 5.7 years). For all patients, lacunes were an incidental finding with no corresponding clinical deficits. The factor most predictive of lacunar development was age less than 5 years at the time of radiotherapy (P =.010). There was no significant difference in estimated decline in intelligence quotient scores between patients with lacunes and age and diagnosis-matched controls.

CONCLUSION

Lacunes may be caused by therapy-induced vasculopathy in children with brain tumors, with the most significant predictor being age less than 5 years at the time of radiotherapy.

SIOP Working Committee on Psychosocial issues in pediatric oncology: guidelines for care of long-term survivors

This is the third official document of the SIOP Working Committee on Psychosocial issues in pediatric oncology constituted in 1991. This document develops another topic already discussed and approved by the SIOP committee. The topic: "Care of long-term survivors" is addressed to the pediatric oncology community as guidelines that could be followed for considering this issue in a more appropriate way.

Coming to terms: parents' response to a first cancer recurrence in their child

The purpose of this study was to explore, using grounded theory, the process experienced by parents who are dealing with the first recurrence of cancer in their child. The sample of 33 guardians (27 mothers, 1 grandmother, and 5 fathers) was drawn from three pediatric oncology settings. Data were collected through interviews, observations, and medical record review. Thirteen parents were interviewed to validate first the evolving and, later, the complete study findings. Four interactive components emerged: regulating shock, situation monitoring, alternating realizations, and eyeing care-limiting decisions. The overall organizing construct induced from these components was labeled "coming to terms." This construct represents the parents' efforts to overcome shock and despair to make wise decisions about treatment while accepting that the outcome if beyond their control, and to help their child have the optimal chance for cure while preparing for the child's possible death.

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.

Psychological effects of bone marrow transplantation on children and adolescents: preliminary report of a longitudinal study

The number of pediatric bone marrow transplantation (BMT) survivors is growing rapidly, yet little is known about the long-term neuropsychologic and psychosocial sequelae of this procedure. Using a prospective, longitudinal design, 64 pediatric patients undergoing BMT were evaluated with standardized measures of global intelligence, academic achievement and selected tests of neuropsychologic function. In addition, adjustment was assessed with parent and patient report measures of social competence, behavior problems and self-esteem. Patients were evaluated prior to admission for BMT, and again in the period 6-12 months after BMT. Longitudinal findings are reported on an initial cohort of 25 survivors. Cognitive and neuropsychologic function remained stable during the study period. The few significant changes from baseline which were observed were in the direction of improvement, and may be attributed to practice effects. In contrast, declines were observed in patient social competence, self-esteem and general emotional well-being. BMT conditioning regimens appear not to be associated with significant neuropsychologic impairment in the first year after transplant. However, a longer period of follow-up is necessary before neuropsychologic late-effects can be ruled out. The first year after BMT is characterized by significant psychosocial difficulties for survivors. Adjustment issues may provide a more salient focus of study during this time frame.

High-activity 125I interstitial irradiation in the treatment of pediatric central nervous system tumors: a pilot study

Malignant pediatric tumors of the central nervous system (CNS) have a poor prognosis, with local failure rates as high as 50%. In an attempt to improve local tumor control, we used stereotactic interstitial therapy with 125I implants in patients with recurrent/secondary or newly diagnosed CNS malignancies. Catheters were placed using computed tomography (CT) guidance; computerized dosimetry was completed with the aid of orthogonal films. Implants delivered 1,000 cGy/day to the tumor periphery (0.5 cm beyond the boundary of enhancement on CT scans), to a total dose of 60 Gy. Hyperfractionated external beam irradiation (HEBI), started 2-4 weeks after removal of implants, delivered total doses of 66-70.4 Gy in 110-cGy fractions twice daily to a 3-cm margin around the implant volume. Eight of the 11 patients with newly diagnosed tumors also received 48.4 Gy HEBI to the craniospinal axis. Tumor regression was noted at 2 months after implantation in the 4 patients treated for recurrent/secondary tumors; local progression was subsequently documented in 2 cases at 6 and 20 months after implantation, while a third patient died 6 months after implantation with no evidence of local recurrence. The remaining recurrent/secondary tumor patient has no evidence of active recurrence 15 months after implantation. Local control was maintained in 9 of the 11 patients treated for primary tumors for a median of 27 months (range 15 to 48+ months). The two local failures occurred at 5 and 7 months after implantation. Six patients are alive without evidence of progressive disease (median = 23 months after implantation). There were no severe acute toxicities, but 7 patients later developed histologically confirmed tumor necrosis. Quality of life assessment (QLA) following initial primary therapy with implantation was evaluated utilizing an established criteria and found to be excellent with only one child showing marked QLA score decrease which was related to neurosurgical intervention for radiation-induced necrosis and dysfunctional family social situation. This small series suggests that stereotactic 125I implantation followed by HEBI merits further evaluation in selected children with supratentorial malignant lesions.

Long-term sequelae of therapy for childhood acute lymphoblastic leukaemia

Childhood ALL has provided the model for basic therapeutic principles in the past and now provides the model for late effects studies. Common threads which run throughout the literature in this area of clinical research are the importance of young age with increased vulnerability to long-term treatment induced sequelae and the relatively large contribution of radiation as compared with chemotherapy in the pathogenesis of adverse sequelae. Previous retrospective studies of long-term childhood ALL survivors focused on neuropsychologic changes and anatomic changes in the CNS after cranial irradiation. More recent retrospective studies have made the following new observations: (i) the high frequency of significant short adult stature in those less than 6 years of age at diagnosis who received 24 Gy cranial irradiation; (ii) actuarial risk of 2.5% of developing a second malignancy with approximately one-half of secondary malignancies occurring in the CNS in children 5 years of age or less who received cranial irradiation; (iii) the association of secondary ANLL with epipodophyllo-toxin use, and (iv) delayed cardiac toxicity despite anthracycline dosage reduction. Current therapy regimens, especially in high-risk patients, are both more successful and more intensive than those used in the past. While it will be another decade before many of the long-term sequelae begin to emerge, one can anticipate, based on current experience, some of the problems that will occur.

Comparison of neuropsychologic functioning and clinical indicators of neurotoxicity in long-term survivors of childhood leukemia given cranial radiation or parenteral methotrexate: a prospective study

We prospectively compared neuropsychologic functioning and clinical indicators of neurotoxicity in 49 consecutive childhood leukemia patients in long-term continuous complete remission (CR) who had received two different regimens of CNS prophylaxis by random assignment. Twenty-three patients were treated with 1,800 cGy cranial radiation and intrathecal methotrexate (RT group) and 26 with parenteral methotrexate only (MTX group). Over half of the RT group had somnolence syndrome, and four developed cerebral calcifications late in their clinical course. Abnormal electroencephalograms (EEGs) were seen in 15 patients in the MTX group, and six had early, transient white-matter hypodensities apparent on computed tomographic (CT) scans. Mean scores on standard tests of intelligence and academic achievement, administered after remission induction and again at a median of 6 years after treatment cessation, did not differ significantly between the two groups. However, statistically significant decreases in overall and verbal intelligence quotients (IQs) and in arithmetic achievement were found within both treatment groups. Sixteen of 26 in the MTX group and 14 of the 23 in the RT group had clinically important decreases (greater than or equal to 15 points) on one or more neuropsychologic measures. These changes did not correlate with findings on CT scans, EEGs, or other clinical signs of neurotoxicity. We conclude that 1,800 cGy cranial radiation and parenteral methotrexate, as used in this study, are associated with comparable decreases in neuropsychologic function.

Treatment of meningeal relapse in childhood acute lymphoblastic leukemia: II. A prospective study of intellectual loss specific to CNS relapse and therapy

Changes in intellectual function during the course of treatment for acute lymphocytic leukemia were studied. Twenty-four children had baseline psychological evaluations and annual reevaluations for 3-6 years postdiagnosis. Treatment in all patients included combination chemotherapy, 2,400 cGy prophylactic cranial irradiation, and intrathecal methotrexate. Central Nervous System (CNS) relapse occurred in eight of these children. It was then treated with 3,000 cGy cranial plus 1,800 cGy spinal irradiation. Patients who remained in continuous complete remission showed no decline in global intelligence quotient (IQ). Patients who experienced CNS relapse had a mean decline of 16 IQ points by 3 years postdiagnosis and the long-term survivors displayed a mean loss of 25 IQ points 5-6 years postdiagnosis. Three of the five long-term survivors of CNS relapse function within the retarded range of mental ability and require special education. The other two have learning problems and display poor academic performance relative to same-age peers. There was no association noted between age at diagnosis and ultimate loss of IQ points. This prospective study suggests that children who receive a second course of cranial irradiation for treatment of CNS relapse are at high risk for significant and progressive intellectual loss.