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J P Krischer

Publications and source records attributed to J P Krischer.

At least 19 recordsLinked to original sources

Second malignancies in young children with primary brain tumors following treatment with prolonged postoperative chemotherapy and delayed irradiation: a Pediatric Oncology Group study.

Between 1986 and 1990, the Pediatric Oncology Group conducted a study in which 198 children younger than 3 years of age with malignant brain tumors were treated with prolonged postoperative chemotherapy in an effort to delay irradiation and reduce long-term neurotoxicity. Children younger than 2 years of age received 24 months of chemotherapy followed by irradiation, and those between 2 and 3 years of age received 12 months of chemotherapy plus irradiation. Chemotherapy was given in 28-day cycles (AAB, AAB), with cycle A = vincristine (0.065 mg/kg) intravenously on days 1 and 8 and cyclophosphamide (65 mg/kg) intravenously on day 1, and cycle B = cisplatinum (4 mg/kg) intravenously on day 1 and etoposide (6.5 mg/kg) intravenously on days 3 and 4. Five of the 198 children developed second malignancies, with a cumulative risk at 8 years of 11.3% (95% confidence interval [CI], 0-39%). Four of the five second malignancies occurred in children younger than 2 years of age at diagnosis, with a cumulative risk at 8 years of 18.9% (CI, 0-70%). Initial diagnoses were choroid plexus carcinoma (2 children), ependymoma (1 child), desmoplastic infantile ganglioglioma (2 children), and medulloblastoma (1 child). Duration from diagnosis of initial tumor to second malignancy was 33, 35, 57, 66, and 92 months. Three children younger than 2 years of age developed lymphoproliferative disease, that is, myelodysplastic syndrome (2 children), both with monosomy 7 deletions, and acute myelogenous leukemia (1 child), after 24 to 26 cycles of chemotherapy, including 8 cycles of etoposide. Two of 3 received craniospinal irradiation (2,560/3,840 cGy) and (3,520/5,320 cGy). Time to second malignancy was 7 years 8 months, 4 years 9 months, and 2 years 9 months. Two children developed solid tumors, at 5 years 6 months and 2 years 11 months, respectively, after initiation of treatment. A sarcoma developed after 26 cycles of chemotherapy and no irradiation, and a meningioma developed after 12 cycles of chemotherapy and local craniospinal irradiation. Potential causative factors for this high rate of secondary malignancies include prolonged use of alkylating agents and etoposide with or without irradiation.

Antineoplastic Combined Chemotherapy Protocols

Prognostic factors in infants and very young children with intracranial ependymomas.

The Pediatric Oncology Group (1986-1990) conducted a study in which 48 children <3 years of age with intracranial ependymomas were treated with prolonged postoperative chemotherapy (CT) and delayed RT. Thirty-one children, 0-23 months of age at diagnosis (Gp A) received 2 years of CT followed by RT; while 17 children, 24-36 months of age at diagnosis (Gp B) received CT for 1 year followed by radiation. One-year survivals were 87% (Gp A) and 94% (Gp B) and 2-year survivals were 67% (Gp A) and 82% (Gp B). In subsequent years a significant divergence in survivals according to age has been noted (p = 0.04). Five-year survivals were 25.7% (Gp A) vs. 63.3% (Gp B). The curves began to diverge 1 year following diagnosis. Other than age, the only significant prognostic factor was degree of surgical resection: 5-year survivals were 66% (total resection) vs. 25% (subtotal resection). Neither the presence of metastases, degree of anaplasia nor the degree of surgical resection varied significantly according to age at diagnosis. The most likely reason for the difference in survivals between the two age groups relates to the timing of radiation following CT, i.e., 1-year delay in children 24-36 months of age compared to a 2-year delay in children 0-23 months of age. An alternative but less likely hypothesis is that ependymomas in the younger children have a more aggressive biology. In contrast, survivals in the 24- to 36-month group are much better than previous reports in the literature suggesting that prolonged postoperative CT may allow both a delay in CRT as well as provide improved survivals. Based on these results, future treatment trials should emphasize maximal surgical resection and a delay in radiation of no more than 1 year.

Age Distribution

Clinical cardiotoxicity following anthracycline treatment for childhood cancer: the Pediatric Oncology Group experience.

PURPOSE: To determine the incidence of clinical cardiotoxicity from anthracycline chemotherapy in children with cancer and to identify associated risk factors. PATIENTS AND METHODS: The study population consisted of 6,493 children with cancer who had received anthracycline chemotherapy on Pediatric Oncology Group (POG) protocols from 1974 to 1990. Cardiotoxicity, defined as congestive heart failure not due to other causes, abnormal measurements of cardiac function that prompted discontinuation of therapy, or sudden death from presumed cardiac causes, was determined by a review of protocol records. RESULTS: Cardiotoxicity was confirmed in 106 patients (1.6%): 58 had congestive heart failure, 43 had changes in measures of cardiac function that prompted the discontinuation of therapy, and five died suddenly from presumed cardiac causes. In a multivariate analysis, factors that contributed to the relative risk (RR) of toxicity were a cumulative anthracycline dose > or = 550 mg/m2 of body-surface area (RR = 5.2), maximal dose > or = 50 mg/m2 (RR = 2.8), female sex (RR = 1.9), black race (RR = 1.7), presence of trisomy 21 (RR = 3.4), and exposure to amsacrine (RR = 2.6). Cardiotoxicity within 1 year after the completion of anthracycline treatment (early cardiotoxicity) represented 89.5% of all cases. CONCLUSION: Early clinical cardiotoxicity in children treated with anthracycline is rare. A high maximal dose, or cumulative dose of anthracycline, female sex, black race, presence of trisomy 21, and treatment with amsacrine increase the risk for anthracycline-associated cardiotoxicity.

Adolescent

High-dose chemotherapy with autologous stem-cell rescue in patients with recurrent and high-risk pediatric brain tumors.

PURPOSE: We treated 49 patients with recurrent or poor-prognosis CNS malignancies with high-dose chemotherapy regimens followed by autologous marrow rescue with or without peripheral-blood stem-cell augmentation to determine the toxicity of and event-free survival after these regimens. PATIENTS AND METHODS: Nineteen patients had medulloblastomas, 12 had glial tumors, seven had pineoblastomas, five had ependymomas, three had primitive neuroectodermal tumors, two had germ cell tumors, and one had fibrosarcoma. Thirty-seven received chemotherapy with cyclophosphamide 1.5 g/m2 daily x 4 and melphalan 25 to 60 mg/m2 daily x 3. Nine received busulfan 37.5 mg/m2 every 6 hours x 16 and melphalan 180 mg/m2 (n = 7) or 140 mg/m2 (n = 2). Three received carboplatin 700 mg/m2/d on days -7, -5, and -3 and etoposide 500 mg/m2/d on days -6, -4, and -2. All patients received standard supportive care. RESULTS: Eighteen of 49 patients survive event-free 22+ to 55+ months (median, 33+) after transplantation, including nine of 16 treated before recurrence and nine of 33 treated after recurrence. There was one transplant-related death from pulmonary aspergillosis. Of five patients assessable for disease response, one had a partial remission (2 months), one has had stable disease (55+ months), and three showed progression 2, 5, and 8 months after transplantation. CONCLUSION: The toxicity of these regimens was tolerable. Certain patients with high-risk CNS malignancies may benefit from such a treatment approach. Subsequent trials should attempt to determine which patients are most likely to benefit from high-dose chemotherapy with autologous stem-cell rescue.

Adolescent

Lack of efficacy of postoperative chemotherapy and delayed radiation in very young children with pineoblastoma. Pediatric Oncology Group.

Eleven infants with pineoblastomas were treated with prolonged postoperative chemotherapy in an attempt to delay radiation and reduce neurotoxicity. These infants were part of the Pediatric Oncology Group infant brain tumor study but the outcome of infants with pineoblastomas was not previously reported. Ages ranged from 1 month to 35 months, with eight of 11 < or = 12 months at diagnosis. Four had + cytology and three had + myelograms at diagnosis. The majority had partial surgical resection (25-75% reduction in tumor) and 10 had shunts. Chemotherapy consisted of two 28-day cycles of cyclophosphamide plus vincristine, followed by one 28-day cycle of cisplatin plus etoposide. Craniospinal radiation was planned following completion of either 2 years of chemotherapy (children less than 24 months at diagnosis) or following one year (children 24-36 months at diagnosis). Neuroimaging results following two cycles of cyclophosphamide and vincristine were one partial response, five stable disease, and five progressive disease. There were no responders in the leptomeninges. All children ultimately failed chemotherapy (2 months-11 months). Nine failed in the primary site. Of those eight children in whom a metastatic workup was performed at time of progression, all had evidence of leptomeningeal disease. Six received radiation following failure on chemotherapy. All failed either in the primary site, leptomeninges or extraneurally (peritoneal cavity). All children died. Survival following diagnosis ranged from 4 months to 13 months. This chemotherapy regimen was neither effective in controlling tumor in the primary site nor in treating or preventing leptomeningeal spread.

Antineoplastic Combined Chemotherapy Protocols

Prognostic implications of chromosome 17p deletions in human medulloblastomas.

DNA derived from medulloblastoma biopsies was analyzed to determine if deletions of the 17p region, mutations of the TP53 gene, or amplification of the c-myc, N-myc, EGFR (epidermal growth factor receptor), or MDM2 (murine double-minute-2) genes was indicative of a poor prognosis. Loss of heterozygosity for 17p, observed in 8/28 (29%) paired samples, was associated with a shortened survival period (p = 0.045 by the logrank test). TP53 mutations occurred in 2/46 (4.3%) tumor samples. c-myc Amplification was seen in 3/43 (6.9%) cases, while none of the tumors contained amplified N-myc, EGFR, or MDM2 genes. These results demonstrate that, while only rare medulloblastomas contain TP53 gene mutations or amplification of the c-myc gene, loss of heterozygosity on chromosome 17p is indicative of a significantly worse prognosis among patients with these tumors. Further, these results provide a strong impetus for a prospective analysis of loss of heterozygosity in a cooperative group setting, which would include tumor staging, a selection of treatment modalities, and multivariate analyses.

Adolescent

A phase II study of every other day high-dose ifosfamide in pediatric brain tumors: a Pediatric Oncology Group Study.

Despite reported activity in many other solid tumors, high-dose ifosfamide produces few objective responses in recurrent pediatric brain tumors. Alkylating agents such as cyclophosphamide (CYCLO) possess good activity in many of solid tumors, including brain tumors. Although Ifosfamide (IFOS), a structural congener of CYCLO, has been suggested to have greater activity in several tumors, its activity in brain tumors is uncertain. We conducted a phase II trial of every-other day IFOS (3 gm/M2/qod x 3) in 87 recurrent pediatric brain tumors. Responses were evaluable in 71 patients. Partial responses occurred in 1/6 patients with low grade astrocytoma, 1/16 with malignant glioma, 1/16 with medulloblastoma, 1/3 with pineoblastoma and 1/12 patients with ependymoma. No responses occurred among 10 patients with brain stem gliomas or 8 patients with other brain tumors. Despite the poor objective response rate, 23/71 patients were clinically and imaging stable for periods of 8-62 weeks. There was no relationship between prior CYCLO treatment and subsequent response or failure with IFOS. The predominant toxicity was myelosuppression. Although generally reversible, prolonged suppression and sepsis were responsible for the deaths of 3 heavily pretreated patients. Renal toxicity was uncommon; 2 patients had grade III, and one grade IV renal tubular dysfunction. One patient had grade IV hematuria. Neurotoxicity was less common than in studies of daily ifosfamide; only 1 patient had grade IV neurotoxicity. Three patients had grade III or IV IFOS related hyponatremia. Despite the good stable disease rate, the poor rate of objective response suggests that IFOS monotherapy possesses little clinically meaningful activity in brain tumors.

Adolescent

An automated patient registration and treatment randomization system.

Centralized patient registration and treatment randomization for multicenter clinical trials has many advantages over other approaches. Our Automated Patient Registration and Treatment Randomization system is a fully automated Interactive Voice Response, microcomputer-based application which can operate unattended and is continuously available to provide patient registration and treatment randomization. Several techniques are employed to ensure security of the system and validity and accuracy of the data. Several randomization methods were implemented to support different study designs including balanced block randomization, stratified permuted block scheme, and a sophisticated randomization design based on the minimization method and Zelen's adaptive randomization method for institution balancing.

Clinical Trials as Topic

Ifosfamide/carboplatin/etoposide (ICE) for recurrent malignant solid tumors of childhood: a Pediatric Oncology Group Phase I/II study.

PURPOSE: The combination of ifosfamide (I) and etoposide (E) was useful in salvaging patients with recurrent/resistant malignant solid tumors of childhood. Carboplatin (C), active against a number of pediatric cancers, was added to I and E to form a three-drug combination called ICE to improve the response rate. PATIENTS AND METHODS: ICE, consisting of I 1.5 g/m2 plus E 100 mg/m2 i.v.q.d. x 3 plus C i.v. on day 3 only, was given in 21-28-day intervals. C was started at 300 mg/m2, and the dose was escalated in 25% increments, with three evaluable patients treated at each level. RESULTS: Ninety-two patients were enrolled in this phase I/II study between July 1990 and April 1993. A total of 331 courses of ICE was administered. Median courses of ICE received were three (range, 1-16). The maximum tolerated dose (MTD) for C when used in combination was found to be 635 mg/m2. The response rate for ICE at the MTD for C was complete response (CR) 26% and CR + partial response (PR) 53%. The response was even better in those who received C at the MTD: 32% achieving a CR and 63% a CR + PR. Pancytopenia was the dose-limiting toxicity. Thirteen episodes of bacterial infection were reported, none fatal. Only one patient developed a Fanconi-like syndrome. CONCLUSION: The MTD of C when used with I and E was found to be 635 mg/m2. The overall CR + PR rate for all patients treated at all C dose levels was 53%. Best responses were seen in non-Hodgkin's lymphoma, neuroblastoma, soft tissue sarcomas, and Wilms' tumor.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

Postoperative chemotherapy and delayed radiation in infants and very young children with choroid plexus carcinomas. The Pediatric Oncology Group.

Eight infants with choroid plexus carcinomas were treated with surgery, prolonged postoperative chemotherapy and delayed radiation. The results suggest that some infants with choroid plexus carcinomas can be successfully treated with multimodality therapy, even allowing children with less than a gross total resection to have prolonged disease-free intervals.

Antineoplastic Combined Chemotherapy Protocols

Age and family relationship accentuate the risk of insulin-dependent diabetes mellitus (IDDM) in relatives of patients with IDDM.

The international community of diabetologists is rapidly becoming involved in intervention trials aimed at preventing insulin-dependent diabetes in high risk relatives. Whereas age and relationship to a proband with insulin-dependent diabetes mellitus interacting with detected islet cell autoantibodies (ICA) are risk factors, their independent contribution to that risk remains unclear. In a prospective study of 6851 nondiabetic relatives of 2742 probands conducted between 1979-1993, we found age, but not relationship, to be a dramatic risk variable in ICA-positive persons as estimated by the Cox regression model. The 5-yr risk of insulin-dependent diabetes mellitus was 66% for those found to have ICA detectable before age 10 yr, falling progressively to less than 16% for ICA-positive relatives over age 40 yr. In ICA-negative relatives, age and relationship are independent prognostic variables.

Adolescent

Desmoplastic infantile gangliogliomas: an approach to therapy.

Desmoplastic infantile gangliogliomas are massive cystic tumors, typically occurring in the cerebral hemispheres of infants. They are remarkable pathologically for a prominent desmoplasia and, in some cases, for a cellular mitotically active component that can be readily interpreted as a malignant neoplasm. Four children less than 1 year of age were diagnosed with desmoplastic infantile gangliogliomas in the Pediatric Oncology Group infant brain tumor study (Protocol number 8633). All had been diagnosed by their respective institutions as having malignant tumors, i.e., Grade III astrocytoma, malignant meningioma, leptomeningeal fibrosarcoma, and gliosarcoma. All had increased intracranial pressure, and two had seizures. The tumors were extremely large, with one measuring 12 x 9 x 9 cm. None had evidence of metastatic disease. One patient had a gross total resection, and the other three had debulking procedures. All four children were treated with chemotherapy (cyclophosphamide, vincristine, cisplatinum, etoposide) for periods ranging from 12 to 24 months. Of those with postoperative measurable disease, one child had a complete response, one a partial response, and one had stable disease at the conclusion of chemotherapy. No child received radiation therapy. All children are alive with progression-free survivals after diagnosis of more than 36, 42, 48, and 60 months, respectively. Although desmoplastic infantile gangliomas are rare, recognition of this tumor type is essential because, despite their massive size and pathologically malignant appearance, they may have a relatively benign clinical course. If total surgical resection can be achieved, further therapy may not be indicated. In those patients in whom residual disease is present, chemotherapy appears to be an effective form of therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Antineoplastic Combined Chemotherapy Protocols

Monitoring for anthracycline cardiotoxicity.

OBJECTIVE: To review the basis for recommendations of the Cardiology Committee of the Children's Cancer Study Group, published in Pediatrics, for serial cardiac monitoring of cancer patients during anthracycline therapy and reduction of therapy should cardiac studies show abnormalities. DESIGN: Because the effects of overall morbidity and mortality should be considered when a recommendation is made to withhold potentially lifesaving chemotherapy based on abnormal cardiac findings of patients without clinical evidence of cardiac dysfunction, supporting studies referenced in the published recommendations were reviewed. Specifically, studies were evaluated to determine whether a reduction in anthracycline dose, as a result of abnormal cardiac findings by monitoring, reduced cardiac morbidity and related mortality compared with a prospectively followed control population without dose modification. In addition, the effects of cardiac monitoring and subsequent anthracycline dose modification on oncologic morbidity and mortality were reviewed in these studies. Finally, the contributions of the cardiac and oncologic effects of dose modification were examined to determine the effect of this change in therapy on overall morbidity and mortality. RESULTS: None of the studies cited in developing these recommendations prospectively determined, with controls, the effects of cardiac monitoring and anthracycline dose modification on cardiac, oncologic, or overall morbidity and mortality. Therefore, none of the studies cited in support of cardiac monitoring and subsequent dose reduction demonstrated the efficacy of such an approach. In the absence of such data, concerns are raised as to whether such a monitoring program with subsequent dose modification might do more harm than good. In addition, none of the methods of screening for anthracycline cardiotoxicity has been shown to be adequately predictive of early or late cardiac outcomes. Finally, adoption of these recommendations would inhibit the investigation of the efficacy of the proposed plan. CONCLUSION: Given the absence of supportive data and the potential to do harm, no recommendation for dose modification based on abnormal cardiac findings in patients without clinical evidence of cardiotoxicity can be endorsed, including those of the Cardiology Committee of the Children's Cancer Study Group. When clinical evidence of cardiotoxicity is present, anthracycline dose modification is recommended. A prospective controlled study to determine the effects of dose modification based on cardiac test results is indicated.

Antibiotics, Antineoplastic

Preradiation chemotherapy in advanced medulloblastoma. A Pediatric Oncology Group pilot study.

BACKGROUND: Children diagnosed with medulloblastoma whose tumor involves the brain stem or has spread through the cerebrospinal fluid pathways to other areas of the brain or spinal cord have a poor prognosis despite therapy with surgery, craniospinal irradiation (CSI), and chemotherapy. Preradiation chemotherapy may improve the outlook for these patients. METHODS: To further study the role and feasibility of preradiation chemotherapy, children between the ages of 4 and 21 years diagnosed with advanced medulloblastoma and measurable disease were enrolled in the Pediatric Oncology Group 8695 study. Patients were treated with a 9-week course of vincristine, cisplatin, and cyclophosphamide followed by CSI. Imaging films were reviewed centrally for eligibility and response to chemotherapy. Toxicity to chemotherapy and radiation as well as delays and modifications in subsequent CSI were recorded. RESULTS: Thirteen of 30 fully evaluable patients achieved complete or partial response (43%) to chemotherapy. Toxicity was mostly fever and neutropenia after cyclophosphamide, which is predictable and tolerable. Radiation therapy was delivered in full doses and volumes in most patients but was delayed in its start in most patients. Central review of films revealed frequent use of different imaging modalities at baseline and after therapy, making accurate assessment of tumor response difficult. CONCLUSION: Preradiation chemotherapy with vincristine, cisplatin, and cyclophosphamide is active in patients with advanced medulloblastoma but should be modified to minimize the risk of progressive disease while on therapy and to avoid delays in starting radiation therapy. Consistent use of the same neuroimaging modality is essential in documenting response.

Adolescent

Final results of a study of escalating doses of hyperfractionated radiotherapy in brain stem tumors in children: a Pediatric Oncology Group study.

PURPOSE: In September 1984, the Pediatric Oncology Group began accrual to a Phase I/II study designed to assess the efficacy and toxicity of sequentially escalated doses of hyperfractionated (twice daily) radiotherapy in children with poor-prognosis brain stem tumors. Pediatric Oncology Group Study #8495 closed in June 1990 with a total of 136 patients on study. We report here the outcome of patients treated at the third and final dose level (75.6 Gy), and compare the results to those obtained at the 66 and 70.2 Gy dose levels. METHODS AND MATERIALS: Patients eligible for study were those between 3 and 21 years of age with previously untreated tumors arising in the midbrain, pons or medulla. Histological confirmation of diagnosis was not mandatory provided that the clinical and radiological findings were typical for brain stem glioma. Treatment consisted of radiotherapy delivered to local fields. At the third dose level, fraction sizes of 1.26 Gy were given twice daily, with a minimum interfraction interval of 6 hr to a dose of 75.6 Gy in 60 fractions over 6 weeks. Between 5/89 and 6/90, 41 patients were accrued to the study. Two were excluded from analysis leaving 39 evaluable patients, 21 male and 19 female, whose ages ranged from 3 to 15 years (median 7.5 years). RESULTS: Following treatment, neurological improvement was reported in 30/39 (77%) of the patients. On central review of imaging studies in 29 patients, one patient was found to have had a complete response to radiotherapy, five a partial (> 50% response), and only three had non-responding or progressive disease. The median time to disease progression was 7 months; median survival time was 10 months; survival at 1 year was 39.9% (SE 8.3%) and at 2 years, 7% (SE 4.8%). The pattern of failure was local in all patients; in addition six had evidence of leptomeningeal seeding. Morbidity of treatment included an enhanced skin reaction (21%), otitis media and/or externa (26%), and steroid use > 3 months (62%). Intralesional necrosis was a frequent finding (45%) on imaging studies performed at a median time of 6 weeks post treatment. CONCLUSION: The results of treatment in terms of progression-free survival and overall survival are not significantly different (at p = .55 and p = .46, respectively) from those obtained at the two previous dose levels. There is no evidence that higher doses of hyperfractionated radiotherapy given as in this study improve the outlook of patients with poor-risk brain stem gliomas.

Adolescent

Pre-irradiation chemotherapy and hyperfractionated radiation therapy 66 Gy for children with brain stem tumors. A phase II study of the Pediatric Oncology Group, Protocol 8833.

BACKGROUND: Fewer than 20% of children with intrinsic brain stem tumors survive longer than 2 years. Although some improvement has been noted in recent trials using higher doses of hyperfractionated radiation therapy (HRT), the feasibility of pre-irradiation chemotherapy has not been explored in these patients with poor prognosis. METHODS: Between February 1988 and March 1989, 37 patients were entered onto a Phase II Pediatric Oncology Group study for evaluating the feasibility, response, and toxicity of treating children with high-risk brain stem tumors with chemotherapy followed by HRT (66 Gy). Chemotherapy consisted of four cycles of cisplatin (100 mg/m2) plus cyclophosphamide (3 g/m2). RESULTS: Of 32 eligible patients, 65% improved clinically during the first 2-3 cycles of chemotherapy; 75% of those improving were weaned from steroids. On neuroradiology review of scans before and after chemotherapy, 3 patients had partial responses (PR, > 50% shrinkage), 23 had stable disease (SD), and 6 had progressive disease (PD). The median survival was 9 months. The three patients who attained a PR on chemotherapy were among the longest survivors at 38 plus, 44 plus, and 40 months. Toxicities included profound but brief marrow suppression, transient electrolyte-renal dysfunction, and ototoxicity. Brain stem swelling from intravenous fluids caused transient deterioration in two patients. Six patients developed an unusual syndrome of transient marrow suppression after HRT. CONCLUSIONS: This study suggests that pre-irradiation chemotherapy can be successfully added to the treatment of patients with brain stem tumors with both clinical and objective responses noted, but that other agents must be identified to overcome the apparent development of drug resistance and to improve survival.

Adolescent

Postoperative chemotherapy and delayed radiation in children less than three years of age with malignant brain tumors.

BACKGROUND: Among patients with malignant brain tumors, infants and very young children have the worst prognosis and the most severe treatment-related neurotoxic effects. Therefore, in 1986, the Pediatric Oncology Group began a study in which postoperative chemotherapy was given in order to permit a delay in the delivery of radiation to the developing brain. METHODS: Children under 36 months of age with biopsy-proved malignant brain tumors were treated postoperatively with two 28-day cycles of cyclophosphamide plus vincristine, followed by one 28-day cycle of cisplatin plus etoposide. This sequence was repeated until the disease progressed or for two years in 132 children 24 months of age at diagnosis and for one year in 66 children 24 to 36 months of age at diagnosis. After this, the patients received radiation therapy. The response to the first two cycles of chemotherapy was measured in 102 patients with residual postoperative disease. RESULTS: The first two cycles of cyclophosphamide and vincristine produced complete or partial responses in 39 percent of the 102 patients who could be evaluated. The response rates were highest among patients with medulloblastomas, malignant gliomas, or ependymomas. Patients with brain-stem gliomas or embryonal tumors (primitive neuroectodermal tumors) had little or no response. The progression-free survival rate was 41 percent at one year for children who were 24 to 36 months old at diagnosis and 39 percent at two years for those under 24 months of age at diagnosis. Multivariate analysis identified embryonal tumors as a significant adverse prognostic feature (relative risk, 2.2; 95 percent confidence interval, 1.4 to 3.4) and complete resection as a favorable feature (relative risk, 0.33; 95 percent confidence interval, 0.20 to 0.54). Complete responses to chemotherapy were associated with a progression-free survival rate approaching that achieved with gross total resection. A comparison of cognitive evaluations obtained at base line and after one year of chemotherapy revealed no evidence of deterioration in cognitive function. CONCLUSIONS: Chemotherapy appears to be an effective primary postoperative treatment for many malignant brain tumors in young children. Disease control for one or two years in a large minority of patients permitted a delay in the delivery of radiation and, on the basis of preliminary results, a reduction in neurotoxicity. For patients who had undergone total surgical resection or who had a complete response to chemotherapy, the results are sufficiently encouraging to suggest that radiation therapy may not be needed in this subgroup of children after at least one year of chemotherapy.

Antineoplastic Combined Chemotherapy Protocols