Results of treatment of children with recurrent medulloblastoma/primitive neuroectodermal tumors with lomustine, cisplatin, and vincristine

Role of Radiotherapy in Patients With Relapsed Medulloblastoma

During the last three decades, the management of medulloblastoma (MBL) has made enormous progress with a multidisciplinary approach, incorporating surgery, radiotherapy (RT), and chemotherapy. Despite this improvement, 20%-30% of patients with MBL remain at risk of disease recurrence, with its relapse being possibly fatal. To date, the salvage treatment for relapse remains challenging, and various approaches have been suggested for the retreatment. In this review, I have described the characteristics of patients with relapsed MBL, patterns of relapse and the most commonly prescribed treatment. Further, I have reviewed the studies on re-irradiation and its associated issues to conclusively suggest the RT recommendations for patients with relapsed MBL.

Local and Systemic Therapy of Recurrent Medulloblastomas in Children and Adolescents: Results of the P-HIT-REZ 2005 Study

Simple Summary

A medulloblastoma recurrence is usually associated with an unfavorable prognosis. The German P-HIT-REZ 2005 Study gathered data from patients with relapsed medulloblastomas treated in different, non-randomized therapy arms dependent on preconditions of the patients (previous treatment, comorbidities, relapse pattern), the decision of treating physicians, and the patients’/parents’ choice. A total of 93 evaluable patients with refractory or relapsed medulloblastoma were enrolled. The main aim of this study was to analyze the impact of patient and disease characteristics as well as local and systemic therapies on post-relapse progression-free (PFS) and overall survival (OS). In multivariate analysis, a short time until the first recurrence (<18 months) was the strongest predictor for a worse PFS and OS, which was mainly associated with molecular subgroup 3. Metastatic disease, at relapse, only had a significant impact on OS. Re-biopsy, at relapse, is highly recommended to investigate the histopathological and molecular genetic tumor characteristics and to exclude a secondary malignancy.

Abstract

Recurrent medulloblastomas are associated with survival rates <10%. Adequate multimodal therapy is being discussed as having a major impact on survival. In this study, 93 patients with recurrent medulloblastoma treated in the German P-HIT-REZ 2005 Study were analyzed for survival (PFS, OS) dependent on patient, disease, and treatment characteristics. The median age at the first recurrence was 10.1 years (IQR: 6.9–16.1). Median PFS and OS, at first recurrence, were 7.9 months (CI: 5.7–10.0) and 18.5 months (CI: 13.6–23.5), respectively. Early relapses/progressions (<18 months, n = 30/93) found mainly in molecular subgroup 3 were associated with markedly worse median PFS (HR: 2.34) and OS (HR: 3.26) in regression analyses. A significant survival advantage was found for the use of volume-reducing surgery as well as radiotherapy. Intravenous chemotherapy with carboplatin and etoposide (ivCHT, n = 28/93) showed improved PFS and OS data and the best objective response rate (ORR) was 66.7% compared to oral temozolomide (oCHT, n = 47/93) which was 34.8%. Intraventricular (n = 43) as well as high-dose chemotherapy (n = 17) at first relapse was not related to a significant survival benefit. Although the results are limited due to a non-randomized study design, they may serve as a basis for future treatment decisions in order to improve the patients’ survival.

Radiotherapy in Medulloblastoma-Evolution of Treatment, Current Concepts and Future Perspectives

Simple Summary

Craniospinal irradiation (CSI) is the backbone of medulloblastoma treatment and the first treatment to achieve a cure in many patients. Within the last decades, significant efforts have been made to enhance efficacy in combination with chemotherapy. With this approach, a majority of low- and standard-risk patients can be cured. In parallel, many clinical trials have dealt with CSI-dose reduction and reduction of boost volume in order to decrease long-term toxicity, particularly neurotoxicity. Within these trials, standardized quality assurance has helped to increase the accuracy of treatment and improve prognosis. More recently, advances of radiotherapy techniques such as proton treatment allowed for better sparing of healthy tissue in order to further diminish detrimental long-term effects. Major future challenges are the adaption of radiotherapy regimens to different molecularly defined disease groups alone or together with new targeted agents. Moreover, and even more importantly, innovative combinatorial treatments are needed in high- and very-high risk situations.

Abstract

Medulloblastoma is the most frequent malignant brain tumor in children. During the last decades, the therapeutic landscape has changed significantly with craniospinal irradiation as the backbone of treatment. Survival times have increased and treatments were stratified according to clinical and later molecular risk factors. In this review, current evidence regarding the efficacy and toxicity of radiotherapy in medulloblastoma is summarized and discussed mainly based on data of controlled trials. Current concepts and future perspectives based on current risk classification are outlined. With the introduction of CSI, medulloblastoma has become a curable disease. Due to combination with chemotherapy, survival rates have increased significantly, allowing for a reduction in radiation dose and a decrease of toxicity in low- and standard-risk patients. Furthermore, modern radiotherapy techniques are able to avoid side effects in a fragile patient population. However, high-risk patients remain with relevant mortality and many patients still suffer from treatment related toxicity. Treatment needs to be continually refined with regard to more efficacious combinatorial treatment in the future.

An efficient and novel treatment regimen including temozolomide for medulloblastoma: a case study

Background:

The central nervous system (CNS) embryonal tumour is a rare malignancy reported in adults and more commonly in children. The most available treatments may cause neurological dysfunctions requiring clinical attention.

Case presented:

A 29-year-old male was referred with ataxia and diplopia, and brain imaging revealed a posterior fossa lesion suggesting medulloblastoma. The tumour and related symptoms were notably alleviated following treatment with dexamethasone. Following the recurrence of tumour, a biopsy and pathology report, the diagnosis of desmoplastic/nodular medulloblastoma was confirmed. The patient underwent 18 fractions of 180 cGy spine and whole-brain radiation therapy (RT). In addition, 5400 cGy irradiation in 12 fractions was given to the posterior fossa together with 2 mg/m2 intravenous vincristine (VCR) weekly over 6 weeks. Following a 3-week break, the patient was scheduled to receive 150 mg/m2/day temozolomide for 5 days, 2 mg VCR and 65 mg/m2/day cisplatin every 3 weeks for 8 cycles.

Conclusion:

The patient gained survival benefit to date (60 months since diagnosis) with favourable life quality. The promising response in this one exemplary case study proposes that a combined chemotherapy regimen including temozolomide, vincristine and cisplatin is an effective treatment choice for CNS embryonal tumours following RT; however, the further evaluation and a randomised clinical trial are needed.

Quality of life in long-term survivors treated for metastatic medulloblastoma with a hyperfractionated accelerated radiotherapy (HART) strategy

PURPOSE

An intensive therapeutic strategy for metastatic medulloblastoma was launched in 1998 in our Institution. The aim of this study was to examine the long-term quality of life (QoL) in survivor patients at least 3 years after the end of the treatment.

METHODS

Patients were asked to complete self-administered QoL questionnaires. An index of physical impairment (IPI) was scored (range 0-100; the lower the score the better) based on clinical objective observations. Patients were divided into two groups (lower IPI group, and higher IPI group) and descriptively compared accordingly.

RESULTS

The study was completed by 25/33 eligible patients. Despite patients with a higher IPI reported worse perceived health condition, they had better emotional and psychological scores than those with a lower IPI in all QoL questionnaires.

CONCLUSION

In our sample, patients with more severe objective and perceived physical impairments reported a better psychosocial QoL, possibly because the greater attention paid to them by society and family contributes to a better adjustment in long-term survivors. On this base, it should be recommended that all survivors receive a strong support as the most impaired patients.

Cerebrospinal Fluid Dissemination and Neoplastic Meningitis in Primary Brain Tumors

BACKGROUND

Neoplastic meningitis, also known as leptomeningeal disease, affects the entire neuraxis. The clinical manifestations of the disease may affect the cranial nerves, cerebral hemispheres, or the spine. Because of the extent of disease involvement, treatment options and disease staging should involve all compartments of the cerebrospinal fluid (CSF) and subarachnoid space. Few studies of patients with primary brain tumors have specifically addressed treatment for the secondary complication of neoplastic meningitis. Therapy for neoplastic meningitis is palliative in nature and, rarely, may have a curative intent.

METHODS

A review of the medical literature pertinent to neoplastic meningitis in primary brain tumors was performed. The complication of neoplastic meningitis is described in detail for the various types of primary brain tumors.

RESULTS

Treatment of neoplastic meningitis is complicated because determining who should receive aggressive, central nervous system (CNS)-directed therapy is difficult. In general, the therapeutic response of neoplastic meningitis is a function of CSF cytology and, secondarily, of the clinical improvement in neurological manifestations related to the disease. CSF cytology may manifest a rostrocaudal disassociation; thus, consecutive, negative findings require that both lumbar and ventricular cytological testing are performed to confirm the complete response. Based on data from several prospective, randomized trials extrapolated to primary brain tumors, the median rate of survival for neoplastic meningitis is several months. Oftentimes, therapy directed at palliation may improve quality of life by protecting patients from experiencing continued neurological deterioration.

CONCLUSIONS

Neoplastic meningitis is a complicated disease in which response to therapy varies by histology. Thus, survival rates after CNS-directed therapy will differ by the underlying primary tumor. Optimal therapy of neoplastic meningitis is poorly defined, and few guidelines exist to guide clinicians on the most appropriate choice of therapy.

Phase I study of temozolomide in combination with thiotepa and carboplatin with autologous hematopoietic cell rescue in patients with malignant brain tumors with minimal residual disease

Recurrence of malignant brain tumors results in a poor prognosis with limited treatment options. High-dose chemotherapy with autologous hematopoietic cell rescue (AHCR) has been used in patients with recurrent malignant brain tumors and has shown improved outcomes compared with standard chemotherapy. Temozolomide is standard therapy for glioblastoma and has also shown activity in patients with medulloblastoma/primitive neuro-ectodermal tumor (PNET), particularly those with recurrent disease. Temozolomide was administered twice daily on days -10 to -6, followed by thiotepa 300 mg/m(2) per day and carboplatin dosed using the Calvert formula or body surface area on days -5 to -3, with AHCR day 0. Twenty-seven patients aged 3-46 years were enrolled. Diagnoses included high-grade glioma (n=12); medulloblastoma/PNET (n=9); central nervous system (CNS) germ cell tumor (n=4); ependymoma (n=1) and spinal cord PNET (n=1). Temozolomide doses ranged from 100 mg/m(2) per day to 400 mg/m(2) per day. There were no toxic deaths. Prolonged survival was noted in several patients including those with recurrent high-grade glioma, medulloblastoma and CNS germ cell tumor. Increased doses of temozolomide are feasible with AHCR. A phase II study using temozolomide, carboplatin and thiotepa with AHCR for children with recurrent malignant brain tumors is being conducted through the Pediatric Blood and Marrow Transplant Consortium.

Treatment of recurrent primitive neuroectodermal tumors (PNET) in children and adolescents with high-dose chemotherapy (HDC) and stem cell support: results of the HITREZ 97 multicentre trial

Early studies with high-dose chemotherapy for treatment of relapsed cerebral PNET had shown modest efficacy but considerable toxicity. The HIT97 national trial tested a nonrandomized but stratified relapse protocol using either intensive chemotherapy, potentially high dose, or oral chemotherapy. 72 patients (59 disseminated) whose primary treatment had been surgery (97 %), radiotherapy (88 %), and/or chemotherapy (95 %) were enrolled in the intensive chemotherapy arm at diagnosis of relapse or resistance. As a window for this study they received two courses of a 96-hour infusion with carboplatin and etoposide. A response (complete or partial remission) was documented by MRI. Responders received two more cycles of this therapy and stem cell collection, before they received HDC (carboplatin, etoposide, thiotepa) and stem cell support. All possibilities of local therapy were to be explored and applied. After two courses of chemotherapy there was a 52 % response rate (41/72 patients). The median PFS and OS for all 72 patients were 11.6 and 21.1 months. Patients with medulloblastoma had a longer PFS and OS (12.6 and 22.6 months) than those with other PNETs (3.1 and 12.3 months). Favourable prognostic features were no new signs of clinical impairment and localised disease at relapse diagnosis. For the 27 patients who received HDC the median PFS and OS were 8.4 and 20.2 months, respectively. HDC did not benefit patients with resistant cerebral PNET and was associated with profound haematological and mucosal toxicity (90-100 % grade III, IV), infections (50 % grade III and IV) and severe ototoxicity (50 % grade III, 12.5 % grade IV). Treatment related mortality was 8 %. There was low long-term survival and only 2/72 patients are in continuous remission. Adding HDC in patients who responded to the initial courses of chemotherapy did not improve survival. Patients with relapsed cerebral PNET who respond to conventional chemotherapy do not profit from further augmentation to HDC.

Reirradiation of recurrent medulloblastoma: does clinical benefit outweigh risk for toxicity?

BACKGROUND

Patients with recurrent medulloblastoma (MB) have a dismal prognosis. There has been a reluctance to use radiation in the salvage therapy regimens for these patients because of concerns about toxicity and unknown efficacy. Comparing survival outcomes and toxicities in relapsed patients treated with and without radiation may help to define its role.

METHODS

A retrospective review was conducted that included 38 patients with recurrent MB treated with similar risk-adapted therapy at initial diagnosis; reirradiation was a component of salvage therapy in 14. Overall survival (OS) and toxicity were evaluated according to the use of radiation, prior risk stratification, and other factors.

RESULTS

For relapsed standard-risk patients, the use of additional irradiation resulted in a statistically significant improvement in OS from initial diagnosis (P = .036), with 5- and 10-year OS rates of 55% ± 14% and 33% ± 16% versus 46% ± 14% and 0% for reirradiated patients versus others, respectively. Similar improvement was observed in high-risk patients (P = .003). There was an association between the use of additional irradiation and an increased rate of necrosis as determined by neuroimaging (P = .0468).

CONCLUSIONS

The use of irradiation as a component of salvage therapy for relapsed MB may prolong survival. The benefit appears to be greatest for relapsed standard-risk patients.

Cumulative cisplatin dose is not associated with event-free or overall survival in children with newly diagnosed average-risk medulloblastoma treated with cisplatin based adjuvant chemotherapy: report from the Children's Oncology Group

BACKGROUND

Survival rates for children with medulloblastoma have risen over the past decade, in part due to the addition of cisplatin-containing adjuvant chemotherapy. Total dose of cisplatin required for optimal treatment is unknown. The purpose of this study was to evaluate the survival outcomes based on cumulative cisplatin doses (CCD) in children with newly diagnosed average-risk medulloblastoma.

PROCEDURE

CCD data were reviewed for 363 patients in a prospective study evaluating patients between 3 and 21 years with a newly diagnosed average-risk medulloblastoma and treated with craniospinal radiation and post-radiation cisplatin based adjuvant chemotherapy.

RESULTS

Eight-year event-free survival (EFS) and overall survival (OS) estimates were 78.2 ± 2.6% and 83.9 ± 2.4%, respectively. Only 73 patients received the protocol specified CCD of 600 mg/m(2), primarily due to mandated cisplatin toxicity-related dose reductions. The median CCD given to those without relapse or death on treatment was 487.5 mg/m(2). CCD, as a time-dependent covariate, was not associated with EFS (P = 0.54) or OS (P = 0.11). The 343 patients who completed chemotherapy failure-free were categorized into four groups according to CCD (n = 10; 75-150 mg/m(2)), (n = 26; 151-300 mg/m(2)), (n = 113; 301-450 mg/m(2)), and (n = 194; 451-600 mg/m(2)). There were no statistically significant differences in distributions of EFS (P = 0.53) or OS (P = 0.49) among these four groups.

CONCLUSION

CCD is not associated with EFS or OS suggesting that lower doses of cisplatin may be incorporated into future medulloblastoma trials, thereby limiting its toxicity profile without affecting survival. If ototoxicity is encountered, more stringent cisplatin dose modification/cessation rules seem warranted.

The molecular classification of medulloblastoma: driving the next generation clinical trials

PURPOSE OF REVIEW

Most children diagnosed with cancer today are expected to be cured. Medulloblastoma, the most common pediatric malignant brain tumor, is an example of a disease that has benefitted from advances in diagnostic imaging, surgical techniques, radiation therapy and combination chemotherapy over the past decades. It was an incurable disease 50 years ago, but approximately 70% of children with medulloblastoma are now cured of their disease. However, the pace of increasing the cure rate has slowed over the past 2 decades, and we have likely reached the maximal benefit that can be achieved with cytotoxic therapy and clinical risk stratification. Long-term toxicity of therapy also remains significant. To increase cure rates and decrease long-term toxicity, there is great interest in incorporating biologic 'targeted' therapy into treatment of medulloblastoma, but this will require a paradigm shift in how we classify and study disease.

RECENT FINDINGS

Using genome-based high-throughput analytic techniques, several groups have independently reported methods of molecular classification of medulloblastoma within the past year. This has resulted in a working consensus to view medulloblastoma as four molecular subtypes, including wingless-type murine mammary tumor virus integration site (WNT) pathway subtype, Sonic Hedgehog pathway subtype and two less well defined subtypes (groups C and D).

SUMMARY

Novel classification and risk stratification based on biologic subtypes of disease will form the basis of further study in medulloblastoma and identify specific subtypes that warrant greater research focus.

Prognostic factors after extraneural metastasis of medulloblastoma

PURPOSE

To review the existing literature regarding the characteristics, prognostic factors, treatment, and survival of patients with medulloblastoma, who develop extraneural metastasis (ENM).

METHODS AND MATERIALS

A PubMed search of English language articles from 1961 to 2007 was performed, yielding 47 articles reporting on 119 patients. Factors analyzed included age, time interval to development of ENM, ENM location, central nervous system (CNS) involvement, treatment, and outcome.

RESULTS

Sites of ENM included bone in 84% of patients, bone marrow in 27% of patients, lymph nodes in 15% of patients, lung in 6% of patients, and liver in 6% of patients. Median survival was 8 months after diagnosis of ENM. The 1-, 2-, and 5-year overall survival (OS) rates after diagnosis of ENM were 41.9%, 31.0%, and 26.0%, respectively. The 1-, 2-, and 5-year progression-free survival (PFS) rates after diagnosis of ENM were 34.5%, 23.2%, and 13.4%, respectively. For patients without CNS involvement at the time of ENM diagnosis, the 1-, 2-, and 5-year OS rates for those treated with and without radiotherapy (RT) were 82.4%, 64.8%, and 64.8% vs. 51.0%, 36.6%, and 30.5%, respectively (p = 0.03, log-rank test). RT did not significantly improve OS or PFS rates for those with CNS involvement. Concurrent CNS involvement, ENM in the lung or liver, a time interval of <18 months to development of ENM, and a patient age of <16 years at ENM diagnosis were found to be negative prognostic factors for both OS and PFS.

CONCLUSIONS

Several prognostic factors were identified for patients with ENM from medulloblastoma. Patients without concurrent CNS involvement, who received RT after ENM diagnosis had an OS and PFS benefit compared to those who did not receive RT.

Boost radiosurgery as a strategy after failure of initial management of pediatric primitive neuroectodermal tumors

OBJECT

The aim in this study was to determine the outcomes of boost stereotactic radiosurgery, specifically Gamma Knife surgery (GKS), for recurrent primitive neuroectodermal tumors (PNETs) in children in whom initial multimodality management had failed.

METHODS

The authors performed a retrospective analysis of 7 patients who underwent a total of 15 GKS procedures for locally recurrent or metastatic PNETs. Nine procedures were directed at the primary site, whereas 6 were directed at distant brain sites. All patients received multimodality therapy, including resection, fractionated radiotherapy, and chemotherapy. The mean interval from diagnosis to first stereotactic radiosurgery was 25.8 months (range 11-35 months). The mean tumor volume was 3.9 cm(3) (range 1.1-13.1 cm(3)), and an average marginal dose of 14.5 Gy (range 9-20 Gy) was administered.

RESULTS

Following salvage GKS, 2 patients had early disease progression (median survival of 5 months after GKS). Five patients had late disease progression (complete response in 3, partial response in 1, and stable disease in 1) and a median survival of 30 months after GKS. Four of the 5 patients who had late progression underwent repeat GKS for marginal recurrence. No adverse radiation effects were observed in these 7 patients.

CONCLUSIONS

The GKS modality was a well-tolerated and useful boost strategy in pediatric patients with PNET and a poor prognosis in whom initial multimodality management had failed. However, local or distant disease progression or diffuse leptomeningeal spread ultimately proved fatal to these patients.

Medulloblastoma: what is the role of molecular genetics?

Among pediatric malignancies, medulloblastoma (MB) is one of the most common malignant tumors of the CNS. In the past few years, thanks to a multidisciplinary approach including surgery, chemo- and radiation therapy, survival has significantly improved. Despite that, a third of patients still have a low chance of being cured and long-term survivors experience severe treatment-related sequelae. MBs are usually classified according to a clinical risk stratification, based on histological features, age at diagnosis, extent of tumor resection and presence or absence of metastases. However, these clinical variables have recently been reported to be poor for defining risk-related disease. Retrospective studies have identified histological or biological factors that have distinct roles in prognosis. As several pathways have been discovered to be involved in MB pathogenesis, they should be taken into account to more accurately stratify patients and their treatment and to develop innovative therapies.

Changes mimicking new leptomeningeal disease after intensity-modulated radiotherapy for medulloblastoma

PURPOSE

Acute and late changes in magnetic resonance imaging of the pediatric brain have been described after radiotherapy (RT). We report the post-RT neuroimaging changes in the posterior fossa after intensity-modulated RT (IMRT) in children with medulloblastoma and contrast them with those of leptomeningeal disease.

METHODS AND MATERIALS

We performed a retrospective review of 53 consecutive children with medulloblastoma who were treated with craniospinal RT followed by IMRT to the posterior fossa and chemotherapy between 1997 and 2006.

RESULTS

After IMRT to the posterior fossa, 8 (15%) of 53 patients developed increased fluid-attenuated inversion-recovery signal changes in the brainstem or cerebellum and patchy, multifocal, nodular contrast enhancement at a median of 6 months. The enhancement superficially resembled leptomeningeal disease. However, the enhancement resolved without intervention at a median of 6 months later. The accompanying fluid-attenuated inversion-recovery signal changes occasionally preceded the enhancement, were often parenchymal in location, and resolved or persisted to a lesser degree. All 8 patients with transient magnetic resonance imaging changes in the posterior fossa were alive at last follow-up. In contrast, leptomeningeal disease occurred in 8 (15%) of our 53 patients at a median of 19.5 months after IMRT completion. Of these 8 patients, 7 demonstrated initial nodular enhancement outside the conformal field, and 7 patients died.

CONCLUSION

Magnetic resonance imaging changes can occur in the posterior fossa of children treated with IMRT for medulloblastoma. In our experience, these transient changes occur at a characteristic time and location after RT, allowing them to be distinguished from leptomeningeal disease.

Phase 1 trial of O6-benzylguanine and BCNU in children with CNS tumors: a Children's Oncology Group study

BACKGROUND

Efficacy of nitrosoureas is limited by host repair of drug-induced alkylation. O(6)-benzylguanine (O(6)-BG), an inhibitor of host alkylation repair, and BCNU were studied in children with refractory/untreatable central nervous system tumors to determine dose-limiting toxicities (DLTs) and maximum tolerated dose (MTD) of BCNU administered following O(6)-BG.

PROCEDURE

O(6)-BG (120 mg/m(2) IV over 1 hr) was followed by BCNU (IV over 1 hr). Cohorts of three to six patients were treated with escalating doses of BCNU. Courses were repeated every 6 weeks. Patients in Stage 1 were accrued irrespective of prior treatment. Once the MTD was exceeded, Stage II accrual was limited to less heavily pretreated patients (</= two prior chemotherapy regimens, no prior central axis radiation, no prior bone marrow transplant, and no bone marrow involvement).

RESULTS

Twelve patients in Stage I and 13 in Stage II (less heavily pretreated patients only) were evaluable for toxicity. The MTD of BCNU administered with O(6)-BG (120 mg/m(2) IV) was 58 mg/m(2) in less-heavily pretreated patients. Myelosuppression, which was cumulative in some patients receiving multiple cycles of therapy, was the predominate DLT. Twenty-four patients were evaluable for response: after two courses of therapy, 6 had stable disease, 17 had progressive disease, and 1 patient had a minor response but progressed after four courses of therapy.

CONCLUSIONS

Based on lack of activity of this combination in adult phase II studies, no further testing of O(6)-BG plus BCNU in children is planned. Strategies to decrease hematopoeitic toxicity of BCNU plus O(6)-BG are required.

Vincristine and lomustine induce apoptosis and p21(WAF1) up-regulation in medulloblastoma and normal human epithelial and fibroblast cells

Medulloblastomas arise in the cerebellum and are the most common pediatric primary malignant brain tumors. Currently, medulloblastoma patients are best treated with surgical removal of the tumor, adjuvant radiation therapy and chemotherapy. The chemotherapeutic agents that showed efficiency against medulloblastomas include lomustine and vincristine. However, the effects of these drugs on medulloblastomas as well as on other cell types is still not well defined. In the present report we present evidence that the cytotoxic effect of these drugs is not specific for medulloblastoma cells but includes also normal fibroblast and epithelial cells. We have also shown that vincristine and lomustine trigger apoptosis in all these cells through the mitochondrial pathway via decrease in the level of the anti-apoptosis proteins Bcl-2 and Bcl-xl, respectively. Intriguingly, the proportion of apoptotic cells induced in medulloblastoma and normal epithelial and fibroblastic cells was similar. In addition, vincristine induced low proportion of necrosis in medulloblastoma and normal fibroblast cells. Interestingly, while vincristine induced cell cycle delay in G2/M phase in normal as well as medulloblastoma cells, lomustine effect on the cell cycle was specific for medulloblastoma cells. Furthermore, we have shown that vincristine and lomustine up-regulated p21 protein level in a p53-independent manner. These results shed more light on the biological effects of vincristine and lomustine and show that lomustine is a more specific and potent anti-medulloblastoma agent.

Phase II study of oxaliplatin in children with recurrent or refractory medulloblastoma, supratentorial primitive neuroectodermal tumors, and atypical teratoid rhabdoid tumors: a pediatric brain tumor consortium study

BACKGROUND

An open-label Phase II study of oxaliplatin was conducted to evaluate its safety and efficacy in children with recurrent or refractory medulloblastoma (MB), supratentorial primitive neuroectodermal tumors (SPNET), and atypical teratoid rhabdoid tumor (ATRT).

METHODS

Patients were stratified as follows: stratum IA, first recurrence MB with measurable disease; IB, recurrent MB with only cerebral spinal fluid (CSF) positivity or linear leptomeningeal disease (LLD); IC, MB > or =second recurrence; stratum II, recurrent SPNET; stratum III, recurrent ATRT. Patients received oxaliplatin, 130 mg/m(2) intravenously over 2 hours every 3 weeks. The primary objective was to estimate the sustained response rate in stratum 1A. Plasma ultrafiltrate platinum pharmacokinetics were evaluated.

RESULTS

A total of 43 patients with a median age of 8.5 years (range, 0.6-18.9 years) were enrolled. In stratum 1A, 2 of 15 had partial responses (PRs, 1 sustained PR). No responses were observed in other strata. The most frequent Grade 3 and 4 toxicities included thrombocytopenia (25.6%), neutropenia (16.3%), leukopenia (12%), increase in serum alanine transaminase (ALT) (7%), vomiting (4.7%), and sensory neuropathy (4.7%). No severe ototoxicity or nephrotoxicity was reported. Plasma ultrafiltrate platinum pharmacokinetic parameters were similar to adults, with a median clearance of 12.2 L/hr (range, 4.4-30 L/hr) and median area under the curve (AUC(0-infinity)) of 9.4 microg/mL/hr (range, 6.2-13.9 microg/mL/hr).

CONCLUSIONS

Oxaliplatin was well tolerated in children but has limited activity in children with recurrent CNS embryonal tumors previously treated with platinum compounds.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Harvesting blood stem cells from cranial bone at craniotomy--a preliminary study

Primary brain tumors seldom infiltrate into the cranium, even if they are invasive in the central nervous system. In this study, we examined whether blood stem cells can be harvested from cranial bone at craniotomy. Bone marrow cells in cranial bone were counted in 181 craniotomy specimens after staining with hematoxylin and eosin. Marrow volume was measured in 37 specimens using three-dimensional computed tomography (CT). In 10 cases, viable cells collected from very small bone pieces at craniotomy were cultured to examine granulocyte/macrophage colony-forming units (CFU-GM). In 2 cases, bone marrow cells were practically harvested from removed bone at surgery. The weight of bone flap at craniotomy was 35.0 +/- 18.0 g. Bone flap marrow contained 1.5 x 10(9) cells/ml. CT examination showed that bone flap volume was 35.0 +/- 9.0 ml and marrow ratio was 65.1 +/- 13.5%. Thus, at craniotomy, a typical bone flap contained about 3.4 x 10(10) cells. Bone marrow cell count gradually decreased as subject age increased. The bone pieces obtained at craniotomy contained 3.1 +/- 3.4 x 10(6) cells/g, and CFU-GM count was 0.4 x 10(5) cells/g. In one case, we collected 3.4 x 10(8) cells, including 1.8 x 10(6) CFU-GM colonies. In another case, we collected 9.7 x 10(8) cells, including 4.8 x 10(6) CFU-GM colonies. These findings indicate that, at craniotomy, the number of blood stem cells in a typical bone flap is sufficient for autologous blood stem cell rescue.

MYCC and MYCN oncogene amplification in medulloblastoma. A fluorescence in situ hybridization study on paraffin sections from the Children's Oncology Group

CONTEXT

Brain tumors are the most common solid tumor in childhood, and medulloblastoma is the most common malignant brain tumor in this age group. Cytogenetic abnormalities that have been described in childhood medulloblastoma include loss of 17p, amplification of MYCC (c-myc), amplification of MYCN (N-myc), and isochromosome 17q. Data on these tumors indicate that the frequency of MYCC amplification is 5% to 10%. Fluorescence in situ hybridization is a powerful tool for investigating these features on archival material.

OBJECTIVES

To determine if intratumoral heterogeneity exists for MYCC and MYCN in medulloblastomas and if tumors with amplified MYCC or MYCN exhibit consistent histologic patterns.

DESIGN

In this fluorescence in situ hybridization study, we investigated the frequency and prognostic significance of MYCC and MYCN amplification in 77 medulloblastomas derived from the Children's Oncology Group.

RESULTS

MYCC amplification occurred in only 4 (5.2%) of 77 tumors. The 4 patients died of clinically aggressive neoplasms within 7 months of diagnosis. Similarly, 4 of 77 patients' tumors were found to exhibit MYCN amplification, but survival data are incomplete at present, therefore prognostic significance cannot be characterized.

CONCLUSIONS

These data establish the frequency of MYCC amplification in a large cohort of children with medulloblastoma and further suggest that MYCC amplification may be a marker of poor prognosis. Intratumoral heterogeneity was identified for these oncogenes in that 1 patient's tumor exhibited evidence of both MYCN and MYCC amplification, and this patient experienced a shortened survival time.

Role of radiotherapy in the treatment of supratentorial primitive neuroectodermal tumors in childhood: results of the prospective German brain tumor trials HIT 88/89 and 91

PURPOSE

To evaluate the outcome of children with supratentorial primitive neuroectodermal tumors after surgery, irradiation, and chemotherapy and to identify factors predictive for survival.

PATIENTS AND METHODS

Sixty-three children in the prospective trials HIT 88/89 and HIT 91 were eligible. Complete resection was performed in 21 patients. Patients were randomized for preirradiation chemotherapy, consisting of two cycles of ifosfamide, etoposide, methotrexate, cisplatin, and cytarabine (n = 40), or chemotherapy after irradiation, consisting of eight cycles with cisplatin, vincristine, and lomustine (n = 23). Irradiation volume was recommended to encompass the neuraxis with 35.2-Gy total dose followed by a boost (20.0 Gy) to the primary tumor site (n = 54). Seven patients were irradiated to the tumor region only with a total dose of 54.0 Gy.

RESULTS

Overall survival at 3 years was 48.4%. Progression occurred in 38 children, with local recurrences in 27 patients. The only significant prognostic factor was dose and volume of radiotherapy (progression-free survival after 3 years was 49.3% with correct treatment compared with 6.7% for 15 children with major violations of radiotherapy). Ten early progressions occurred during adjuvant therapy (eight before and two during radiotherapy), nine of them treated with preirradiation chemotherapy. There was a positive trend in outcome for nonmetastatic and pineal tumors.

CONCLUSION

Significant predictive factors were dose and volume of radiotherapy. Volume of irradiation should encompass the whole CNS with additional boost to the tumor region. Local doses of at least 54 Gy and a craniospinal dose of 35 Gy are necessary. Preirradiation chemotherapy seems to increase risk of early progression.

Review of the molecular genetics and chemotherapeutic treatment of adult and paediatric medulloblastoma

Medulloblastoma is the most common primary brain tumour in children and accounts for 25% of newly diagnosed cases. Recent advances in treatment have extended 5-year survival rates from 3 - > 70% during the past 50 years. These improvements in survival have resulted from a multi-modality approach that includes surgical resection, posterior fossa and craniospinal irradiation and chemotherapy for selected, high-risk patients. The literature regarding chemotherapy of adult and paediatric patients is reviewed in-depth. The most active agents include cisplatin, CCNU, cyclophosphamide, vincristine and carboplatin. Although patients are living longer with their disease, neurocognitive function and quality of life are often impaired following radiation therapy (RT) to the developing brain. To safely allow reductions in the dose of RT, the specificity and efficacy of chemotherapy must be improved. Recent advances in the molecular genetics of medulloblastoma transformation (e.g., myc, PTCH ) are reviewed and discussed. A thorough understanding of these pathways will be critical for the development of more specific, novel drugs. Further clinical trials will be needed to evaluate the activity of these new drugs and determine their role in the treatment plan of patients with medulloblastoma.

Prognostic factors and secondary malignancies in childhood medulloblastoma

PURPOSE

Little is known of the outcome of long-term survivors of childhood medulloblastoma, one of the most common pediatric malignancies. To determine the potential for secondary malignancies, a retrospective outcome evaluation in 88 consecutive cases of childhood medulloblastoma was performed.

PATIENTS AND METHODS

The records of all patients with childhood medulloblastoma diagnosed at Children's National Medical Center in Washington, DC from 1969 through 1997 were reviewed.

RESULTS

The median follow-up time was 92 months (range 6-257 months). Overall survival was 59% at 5 years and 52% at 10 years. Univariate analysis showed that age at diagnosis, extent of surgical resection, presence of metastatic disease (M stage), ventriculoperitoneal shunt placement within 30 days from diagnosis, posterior fossa radiation therapy dose, and adjuvant chemotherapy significantly affected survival. Although based on small numbers, the risk of second neoplasms was significantly increased in this cohort. Multiple basal cell carcinomas developed in the areas of radiation therapy in two patients; these patients also had nevoid basal cell carcinoma syndrome (NBCCS) diagnosed. One other patient died of glioblastoma multiforme 8 years after treatment of medulloblastoma. A meningioma developed in another patient 10 years after radiation therapy.

CONCLUSION

As survival of medulloblastoma patients improves, increased surveillance regarding secondary malignancies is required, especially because radiation-induced tumors may occur many years after treatment. These two cases of NBCCS also illustrate the importance of considering the concomitant diagnosis of NBCCS in young patients with medulloblastoma. In those patients, alternative therapy should be considered to minimize radiation therapy-related sequelae.

Chronic oral VP-16 for recurrent medulloblastoma

Chronic oral VP-16 (Etoposide) is a chemotherapy regimen with wide application in oncology and documented efficacy against germ cell tumors, lymphomas, Kaposi sarcoma, and glial brain tumors. Eight patients ranging in age from 4 to 36 years (median 7.5 years) with locally recurrent medulloblastoma were treated with VP-16. No patient displayed evidence of cerebrospinal fluid dissemination, distant brain or spine parenchymal metastases, or extraneural metastatic disease. All patients had previously been treated with surgery (gross total resection, 5; subtotal resection, 3), craniospinal radiotherapy, and platinum-based chemotherapy (adjuvant, 3; salvage, 8). Each cycle of therapy consisted of 21 days of VP-16 (50 mg/m2/day) followed by a 7 to 14 day rest followed by an additional 21 days of VP-16 (50 mg/m2/day). Complete blood counts were obtained weekly. Neurologic examination and brain magnetic resonance imaging scan with contrast were performed prior to each cycle of therapy. Treatment-related complications included: partial alopecia (5 patients); diarrhea (4); weight loss (3); anemia (2); neutropenia (4); and thrombocytopenia (4). Two patients required transfusion and 1 patient received antibiotics for neutropenic fever. All patients were evaluable for response: 3 demonstrated progressive disease after the first cycle of VP-16, 3 had stable disease (range 4 to 6 months) and 2 had partial neuroradiographic responses (8 and 10 months). Median duration of response and stable disease was 6 months (range: 4 to 10 months) in 5 of 8 (62.5%) patients. Chronic oral VP-16 is a well-tolerated and relatively non-toxic chemotherapeutic agent with demonstrated activity in locally recurrent medulloblastoma.

Cure of recurrent medulloblastoma: the contribution of surgical resection at relapse

BACKGROUND

Recurrent medulloblastoma has long been considered universally fatal. In spite of attempts to improve its treatment, only rarely have long term survivors been documented in the world's medical literature. Although the treatment of primary medulloblastoma is well established and includes surgical excision, postsurgical irradiation, and, more recently, chemotherapy, there is no established treatment for its recurrence. Current guidelines dictate the experimental use of chemotherapy, and there have been some encouraging results; yet no increase in long term survival has been documented.

METHODS

This article presents a case of cured recurrent medulloblastoma in which the only intervention at the time of recurrence was surgical excision. In addition, a review of the literature is presented, which evaluates chemotherapeutic trials involving cases of recurrent medulloblastoma.

RESULTS

The authors were surprised to find that the longest survivors of multiple trials had undergone reoperation at the time of recurrence. The authors' case, as well as cases described in the literature, point to a valid treatment alternative largely ignored in the management of recurrent medulloblastoma.

CONCLUSIONS

Reoperation of recurrent brain tumors has received surprisingly little attention in the medical literature. Yet, as this case and a review of the literature demonstrate, this is a useful intervention.

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.

Cyclophosphamide in combination with sargramostim for treatment of recurrent medulloblastoma

Thirteen patients with recurrent medulloblastoma were treated with cyclophosphamide in association with Sargramostim. Cyclophosphamide was given at doses ranging between 1.0-2.5 g/m2 daily for two doses. Sargramostim was given at a fixed dose of 250 micrograms/m2 subcutaneously twice a day beginning 24 hours after the second cyclophosphamide dose and continuing through the leukocyte nadir until the ANC was more than 1,000 cells/microliters for two consecutive days. A total of 33 courses were given with toxicity consisting of grade 4 neutropenia in all courses and grade 3-4 thrombocytopenia in 10 of 13 patients. There were no deaths related to infection or bleeding. Four patients were taken off study because of prolonged myelosuppression. Three of these patients were at the 2.5 g/m2 level, and of these three, two developed lung toxicity (grades 2 and 4, respectively). One patient developed an allergic reaction following the first injection of Sargramostim and was also taken off study. Of 10 evaluable patients, there were 9 PR and 1 SD. We conclude that cyclophosphamide at a dose of 2.0 g/m2/day x 2 days q 4 weeks in association with Sargramostim demonstrates marked activity with acceptable toxicity in patients with recurrent medulloblastoma.

Medulloblastoma and Collins' law: a critical review of the concept of a period of risk for tumor recurrence and patient survival

Collins' law (CL) states that the period of risk for recurrence for a tumor is the age of the patient plus 9 months. Originally a clinical observation in Wilms' tumor, CL has been applied to other tumors such as medulloblastoma (MB). Although CL does not apply to all childhood tumors, it seems to be a valid observation for childhood MB, despite several reports of violations or exceptions to CL in the literature. We sought to test CL in a large population of children with MB from the Childhood Brain Tumor Consortium (CBTC). We analyzed data from 602 children with MB, of whom 421 died and 181 were censored but alive at the last follow-up. We found 16 additional CL exceptions to supplement the 22 already present in the literature. This is both the greatest number of exceptions and the largest MB study population for CL reported to date. We provide clinical data on our 16 uncensored exceptions to CL and critically review those 22 cases cited previously in the literature. All of the CBTC exceptions were under 6 years of age at the time of initial diagnosis and were followed for an average of 7.5 years. All 16 CBTC exceptions died. Children older than 8 years of age could not be followed for a sufficient period of time to be able to state whether CL applies; as age at initial diagnosis increases, the period of observation required to determine CL validity becomes impractically long. Exceptions to CL are rare and amounted to 3.8% of 405 uncensored CBTC patients who died.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Surveillance scanning of children with medulloblastoma

BACKGROUND

The standard follow-up care for children with medulloblastoma includes regular clinical evaluations and surveillance scanning of the central nervous system with computed tomography or magnetic resonance imaging. The evaluations and scanning assess the response of the tumor to treatment, detect any recurrence of disease, and monitor any complications of treatment. We compared the effectiveness of a periodic history taking and physical examination with that of surveillance scanning in detecting recurrent tumors.

METHODS

We reviewed the medical records, including 794 scanning reports or scans, of 86 children with posterior fossa medulloblastoma who were followed regularly between 1980 and 1991. Recurrent tumors were classified as symptomatic if neuroimaging studies had been prompted by clinical symptoms or signs and as radiographic if the tumor had been detected by imaging in an asymptomatic patient.

RESULTS

Twenty-three of the 86 children (27 percent) had a recurrence of tumor. Four recurrences (17 percent) were detected on scanning only, and 19 (83 percent) were associated with symptoms arising a median of four months after the previous scan. The median and range of survival after a recurrence of the tumor were 5 months and < 1 to 38 months, respectively, for a symptomatic recurrence and 20 months and 10 to 32 months, respectively, for a radiographic recurrence (P = 0.03). No patient survived after a recurrence. The longer survival of patients with recurrent tumors detected by scanning most likely reflects the small number of patients and lead-time and length biases associated with screening.

CONCLUSIONS

Among children with medulloblastoma, surveillance scanning is of little clinical value. Scanning detected a minority of recurrences, and no patient who had a recurrence survived.

Carboplatin and VP 16 in medulloblastoma: a phase II Study of the French Society of Pediatric Oncology (SFOP)

The purpose of this study is to evaluate the antitumor activity of combination carboplatin and etoposide in measurable medulloblastoma. From January '89 to January '92, 26 patients with medulloblastoma were included in a multicentric phase II study of 2 courses of carboplatin 160 mg/m2/d day 1 to day 5 and VP16 100 mg/m2/d day 1 to day 5. Median age was 10 years (19 months-14.5 years). First treatment was surgery alone in 1 patient, surgery + radiotherapy in 4 patients, surgery + chemotherapy in 2 patients less than 3 years old, surgery + radiotherapy + chemotherapy in 19 patients ("8 drugs in 1 day" based:17, SIOP I:1, SIOP II:1). Previous treatment included cisplatin (20 cases), carboplatin (1 case), and VP16 (7 cases). Measurable disease was evaluated by CT scan, MRI or myelogram and CSF. Response rate (RR) was 72 +/- 10%:8 complete responses (CR), 10 partial responses (PR), 1 objective effect (OE), 6 progressive disease (PD), 1 non-evaluable. Thirty-six courses were evaluated for toxicity. Median duration of WHO grade 4 neutropenia was 8 days (0-23). One patient died at day 18 after the first course because of diffuse haemorrhage during septic aplasia. Five other non-life-threatening septicemias were recorded. Median number of platelet transfusions was 1 (0-4). One child who had achieved a PR after two courses died from CNS bleeding after the third course. This drug combination achieves a high response rate in childhood medulloblastoma. Severe toxicity has been mainly encountered in previously heavily treated patients. Tolerance may be acceptable in newly diagnosed children, but careful hematological follow-up and platelet transfusional support are definitely mandatory.

Fatal brain stem necrosis after standard posterior fossa radiation and aggressive chemotherapy for metastatic medulloblastoma

A 3-year-old girl received conventional-dose external beam posterior fossa irradiation (5400 cGy in 30 fractions over 40 days) for good-risk medulloblastoma. Soon thereafter, she experienced an extraneural (occipital scar, cervical lymph nodes) and central nervous system (CNS) recurrence. Intensive cisplatin and cyclophosphamide chemotherapy led to rapid disappearance of the extraneural disease. Methotrexate was administered via a ventricular reservoir. After 2 months of chemotherapy, CNS toxicity progressed rapidly from ataxia to paraplegia to quadriplegia to central respiratory failure. Radiographic scans and autopsy material revealed brain stem necrosis. This unusual toxicity raises concern about the safety of aggressive systemic chemotherapy and intrathecal therapy, when given after conventional radiotherapy.

Treatment of early recurrent medulloblastoma in children with cisplatin and etoposide: a preliminary report

The prognosis of recurrent medulloblastoma remains extremely poor. Combination chemotherapy with cisplatin (CDDP) and etoposide (VP-16) was given to five children with early recurrent medulloblastoma. As a rule, CDDP 20 mg/m2 per day and VP-16 60 mg/m2 per day were administered intravenously for 5 days. This cycle was repeated three times at 4-week intervals. After this therapy, cerebellar signs improved in one case and were unchanged in four cases. Weakness and sensory disturbance, however, improved in three of four patients. Moreover, neck and/or back pain resolved in all these four. Radiological findings improved in three cases. Myelosuppression appeared in all patients, but receded rapidly. No other significant complications were noticed. Two patients died 5 and 6 months after this therapy. These results seem to suggest that this therapy has a use in improving neurological symptoms, particularly neck and/or back pain, although its efficacy is limited.

The clinical pharmacology and use of antimicrotubule agents in cancer chemotherapeutics

Although there has been a rapid expansion of the number of classes of compounds with antineoplastic activity, few have played a more vital role in the curative and palliative treatment of cancers than the antimicrotubule agents. Although the vinca alkaloids have been the only subclass of antimicrotubule agents that have had broad experimental and clinical applications in oncologic therapeutics over the last several decades, the taxanes, led by the prototypic agent taxol, are emerging as another very active class of antimicrotubule agents. After briefly reviewing the mechanisms of antineoplastic action and resistance, this article comprehensively reviews the clinical pharmacology, therapeutic applications, and clinical toxicities of selected antimicrotubule agents.

Improved survival with the use of adjuvant chemotherapy in the treatment of medulloblastoma

Between 1975 and 1989, 108 children with newly diagnosed medulloblastoma/primitive neuroectodermal tumor (MB/PNET) of the posterior fossa were treated at the authors' institution. The patients were managed uniformly, and treatment included aggressive surgical resections, postoperative staging evaluations for extent of disease, and craniospinal radiation therapy with a local boost. Beginning in 1983, children with MB/PNET were prospectively assigned to risk groups; those with "standard-risk" MB/PNET were treated with radiation therapy alone, while those in the "poor-risk" group received similar radiation therapy plus adjuvant chemotherapy with 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU), vincristine, and cisplatin. The 5-year actuarial disease-free survival rate for all patients treated between 1975 and 1982 was 68%, and 73% when patients who died within 2 weeks after operation were excluded. This survival rate was statistically better for patients treated after 1982 (82%) compared to those treated between 1975 and 1982 (49%) (p less than 0.004). There was no difference in disease-free survival rates over time for children with standard-risk factors; however, there was a significant difference in the 5-year survival rate for poor-risk patients treated prior to 1982 (35%) compared to those treated later (87%) (p less than 0.001). For the group as a whole, a younger age at diagnosis correlated with a poorer survival rate; however, this relationship between age and outcome was significant only for children treated before 1983 (p less than 0.001). These results demonstrated an encouraging survival rate for children with MB/PNET, especially those treated with aggressive surgical resection followed by both radiation therapy and chemotherapy. The results strongly suggest that chemotherapy has a role for some, and possibly all, children with MB/PNET.

Chemotherapy for medulloblastoma/primitive neuroectodermal tumors of the posterior fossa

Chemotherapy has only marginal efficacy in adult malignant brain tumors. In contrast, drug therapy is considerably more effective in medulloblastoma/primitive neuroectodermal tumors (MB/PNET) of the posterior fossa, the most common childhood primary central nervous system tumor. At the time of disease recurrence, a variety of different single agents and drug combinations result in tumor shrinkage and increased survival. The addition of chemotherapy to standard radiotherapy improves the rate and length of disease-free survival for those children with MB/PNET who have the most extensive tumors at diagnosis. It remains to be determined which drug or drug combinations are the most effective in MB/PNET, and which patients are most likely to benefit from chemotherapy. Chemotherapy may be useful to reduce or, in selected cases, obviate the need for radiotherapy and reduce treatment-related sequelae.