High Dose BCNU Followed by Autologous Bone Marrow Infusion in Glioblastoma Multiforme

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

The use of high-dose chemotherapy with stem cell rescue for malignant brain tumors is reviewed. Promising results have been reported in patients with medulloblastomas, supratentorial PNET's and high-grade astrocytomas. Results thus far have been disappointing for ependymomas and brain stem gliomas. The role of this treatment strategy for other chemotherapy-sensitive tumors such as oligodendrogliomas and central nervous system germ cell tumors has yet to be determined.

High-dose chemotherapy with bone marrow rescue for high-grade gliomas in adults

High-grade malignant gliomas are inevitably fatal, despite every effort to improve this prognosis, including various radiotherapeutic modalities, radio- and chemotherapeutic associations, and combinations of several drugs. High-dose chemotherapy and autologous bone-marrow transplantation (ABMT) have been increasingly used in the last 10 years for solid tumors, and several phase II studies in high-grade glioma patients have been conducted in the setting of both adjuvant treatment and recurrent disease. The most frequently used drug in the conditioning regimens in BCNU at doses higher than that employed by other regimens in other pathologies (800-1000 mg/m2). These dosages involve a high toxicity that is not balanced by a significant improvement in survival. New drugs and/or regimens must be tested in randomized trials.

High dose chemotherapy for the treatment of malignant brain tumors

Conventional treatment of malignant high grade gliomas includes maximal resection followed by external beam radiotherapy. The addition of adjuvant chemotherapy has provided little improvement in the median duration of survival for these patients, particularly those patients with glioblastoma multiforme. The failure of conventional dose chemotherapy to improve the outcome of patients with high grade brain tumors has led several investigators to utilize high dose chemotherapy in order to overcome the limited benefit seen with conventional dose therapy which is due to intrinsic drug resistance as well as the impermeability of blood brain barrier. The majority of published studies utilizing this approach suggest that the addition of high dose chemotherapy with bone marrow transplant is of marginal benefit. However, most of these trials include small numbers of patients with advanced, refractory disease. A few trials have been reported utilizing high dose therapy in an adjuvant setting and the data from these studies are somewhat more promising. This review will analyze these studies and also discuss possible modifications of this approach in order to improve this aggressive treatment for patients who otherwise would have a dismal prognosis.

Radiation therapy for malignant astrocytomas in adults

High grade (or malignant) astrocytomas remain a formidable therapeutic challenge. The main prognostic factors are patient age, patient performance status, tumor grade, the extent of surgical resection and the presence of fits. These factors could help to identify different groups of patients and should be an advantage in deciding on treatment strategies. Modern imaging techniques provide a more precise idea of tumor volume. The study of tumor recurrence shows that they occur in the immediate vicinity of the primary site. Surgery aside, radiotherapy remains the most important treatment modality. Currently, its standards concerning optimal dose and target volume appear to be accepted overall. There is no doubt that a dose-response relation exists; however, doses exceeding 60 Gy increase morbidity. Therefore 60 Gy is the dose most often cited in the literature. Furthermore, as whole brain irradiation does not decrease the risk of recurrence, a focal irradiation including a defined mean volume is generally used today. Radiosensitizers and heavy particles have not fulfilled their initial promise. Brachytherapy remains an interesting alternative for a limited number of patients. Nevertheless, it seems to increase recurrence at a distance from the primary site and to lead to severe focal lesions. Interstitial thermoradiotherapy may minimize local doses and thus help avoid serious local necrosis. Amongst the other therapeutic alternatives, intravenous chemotherapy using nitrosoureas provides a certain but modest benefit. Other administration modalities are currently undergoing evaluation. These include intra-arterial chemotherapy or high dose chemotherapy with auto-bone marrow transplantation. The interest of this latter is concerned mainly with anaplastic astrocytomas. Finally, among the future alternatives, gene therapy appears to hold the most promise. Intensive therapies, combined modality treatments, with the recent help of biological innovations, should be proposed to favorable groups of patients.

High-dose multi-agent chemotherapy followed by bone marrow 'rescue' for malignant astrocytomas of childhood and adolescence

Between April 1986 and March 1989, ten patients under 21 years of age with histologically confirmed malignant astrocytoma, received marrow-ablative chemotherapy with either thiotepa and Etoposide (five patients) or thiotepa, Etoposide and BCNU (five patients), followed by bone marrow 'rescue'. Nine patients had glioblastoma multiforme (GBM), and one patient had an intrinsic brain stem anaplastic astrocytoma (AA). Seven patients were treated for recurrent tumor. Two patients who developed GBM as second malignancies were treated directly following surgical resection. One patient had received irradiation only for recently diagnosed cervical spinal cord GBM. Thiotepa was administered at a total dose of 600-900 mg/M2 over three days, Etoposide was administered at a total dose of 1500 mg/M2 over three days, and BCNU was administered at a total dose of 600 mg/M2 over four days. Non-hematopoietic toxicities have been mainly transient, predictable and acceptable, consisting of oropharyngeal mucositis, cutaneous hyperpigmentation, erythema and desquamation. Four patients achieved complete responses (CR), as determined by radiographic evaluation (CT and/or MRI) on day 28 post-marrow infusion. The mean remission duration of those with CR is 290+ days; two patients presently remain in remission. Two patients achieved partial responses (PR, greater than 50% tumor shrinkage) by day 28 post-marrow infusion; both developed disease progression, at day 61 and 94 post-marrow infusion, respectively. One patient, with a brain stem AA, had stable disease maintained for 13 months post-marrow infusion. With a total (CR + PR) response rate of 60%, these regimens merit evaluation in broader categories of recurrent brain tumor patients, as well as in patients with newly-diagnosed GBM.

Massive chemotherapy with non-frozen autologous bone marrow transplantation in 13 cases of refractory Hodgkin's disease

A group of 13 patients with advanced, diffuse Hodgkin's disease, poorly responding to the most widely employed primary chemotherapy regimens, were treated with massive chemotherapy (MCH) followed by rescue with non-frozen autologous bone marrow infusion (ABMT). Complete remission (CR) was obtained in 8/13 patients (61.5%) and partial remission in two. Hematopoietic recovery occurred in 12 cases. These preliminary results would seem to indicate that MCH with non-frozen ABMT may be successfully used in patients with resistant or relapsed Hodgkin's disease.

High-dose chemotherapy and non-frozen autologous bone marrow transplantation in relapsed advanced lymphomas or those resistant to conventional chemotherapy

Ten patients with advanced, diffuse Hodgkin's and non-Hodgkin's lymphomas responding poorly to the most widely employed primary chemotherapy regimens were treated with a high-dose chemotherapy (HDC) followed by rescue with non-frozen autologous bone marrow infusion (ABMT). Complete remission (CR) was obtained in seven of ten patients (70%) and partial remission in two. Hemopoietic recovery occurred in nine cases. These preliminary results appear to indicate that HDC and non-frozen ABMT may be successfully used in patients with resistant or relapsed lymphomas.

Autologous bone marrow transplantation (ABMT) in the treatment of cancer

Clinical trials in autologous BMT to date have indicated that significant salvage and potential cures can be obtained in patients with high grade non-Hodgkin's lymphoma (NHL) who have failed primary therapy and are treated with high dose chemoradiotherapy and autologous marrow rescue. The major need in NHL is to better define those patients who might benefit by autologous BMT and to reduce the relapse rate by improved pre- or post-transplant therapy. Similar results to those in NHL could be obtained in acute leukemia if occult tumor cells could be eliminated from autologous marrow. Animal model experiments have shown that it is feasible to eliminate low level contamination with tumor cells by in vitro immunologic or pharmacologic treatment. While it is too early to accurately assess the efficacy of ongoing clinical trials using those marrow purging techniques, a few patients have exhibited encouraging durations of CCR. Should these approaches prove to be effective in only a fraction of cases, combination in vitro treatment or the use of more efficient effector mechanisms for cell killing (e.g., ricin conjugated antibody) may very well clear occult tumor from the marrow of most patients. The encouraging results with autologous BMT in leukemia and lymphoma stand in sharp contrast to the disappointing results so far achieved with the non-hematologic solid tumors. It is, however, possible that those cancers have not been subjected to the most rigorous test for successful autologous BMT and that the search for newer agents which can produce operationally irreversible aplasia may provide a fairer test of this approach. It is to be hoped that future research will settle this point.