Multiple Cycles Of High-dose Chemotherapy Research Articles

Use of high-dose chemotherapy in front-line therapy of childhood malignant glioma

Brain tumors are the second most common cancer in pediatric patients and the main cause from death of malignant tumors in this age group. High-grade or malignant glioma, among which anaplastic astrocytomas and glioblastoma are the most prevalent histotypes, represent 10% of pediatric brain tumors and, taken as a whole, are the second most frequent malignant histotype after medulloblastoma. Apart from complete excision followed by full-dose local radiotherapy, chemotherapy appears to provide some benefit to the final outcome. Different trials have explored the role of high-dose chemotherapy that, theoretically, could give an advantage to these patients by overcoming the blood–brain barrier, cell chemoresistance and inducing a wider number of responses. However, it is still doubtful if more responses translate into better outcome and it is not fully understood which patients can experience a true benefit from this treatment strategy. New protocols under evaluation include new agents with specific biological targets, multiple cycles of high-dose chemotherapy, and vaccination, as an immunotherapeutic approach.

Optimization of Conditions for Ex Vivo Expansion of CD34+ Cells From Patients With Stage IV Breast Cancer

Multiple cycles of high-dose chemotherapy can be hematologically supported by repeated administration of peripheral blood progenitors obtained after mobilization using cytokine alone or in combination with chemotherapy. We have explored the quality of such cells and their potential to undergo ex vivo expansion. Twenty-five leukapheresis samples from 19 patients who had received extensive prior chemotherapy for stage IV breast cancer were subjected to CD34+ cell selection using immunoaffinity columns of immunomagnetic bead separation. Cells were cultured in suspension in the presence of c-kit ligand, interleukin-3, interleukin-6, erythropoietin, and granulocyte colony-stimulating factor. Ten experiments were performed using weekly exchange of media and cytokines (Delta assay). Median myeloid and erythroid progenitors expanded 15-fold at 7 days (range, 7 to 43), 40-fold at 14 days (range, 18 to 470), 46-fold at 21 days (range, 0 to 118), and 21-fold at 28 days (range, 0 to 61). In a system using gas-permeable bags without exchange of media or cytokine, median progenitors expanded 13-fold at 7 days (range, 7 to 36), 14-fold at 10 days (range, 4 to 61), 14-fold at 12 days (range, 3 to 46), and 10-fold at 14 days (range, 1 to 35). Progenitor expansion less than 10-fold occurred in 8% of experiments at day 7, in 17% at day 10, in 43% at day 12, and in 50% at day 14. When autologous plasma, autologous plasma processed (removal of cryoprecipitate, centrifugation, then filtration), or human serum were substituted for 20% fetal calf serum, the ratio of progenitor expansion at 7 days relative to 20% fetal calf serum for 10% human serum, 20% human serum, and 1% autologous plasma processed was 1.01 (range, 0.62 to 1.33), 0.88 (range, 0.61 to 1.20), and 0.96 (range, 0.55 to 1.64), respectively. These findings support the feasibility of ex vivo expansion in a system free of nonhuman proteins of CD34(+)-derived progenitors obtained from the peripheral blood of patients who have received prior chemotherapy.

Optimization of conditions for ex vivo expansion of CD34+ cells from patients with stage IV breast cancer

Multiple cycles of high-dose chemotherapy can be hematologically supported by repeated administration of peripheral blood progenitors obtained after mobilization using cytokine alone or in combination with chemotherapy. We have explored the quality of such cells and their potential to undergo ex vivo expansion. Twenty-five leukapheresis samples from 19 patients who had received extensive prior chemotherapy for stage IV breast cancer were subjected to CD34+ cell selection using immunoaffinity columns of immunomagnetic bead separation. Cells were cultured in suspension in the presence of c-kit ligand, interleukin-3, interleukin-6, erythropoietin, and granulocyte colony-stimulating factor. Ten experiments were performed using weekly exchange of media and cytokines (Delta assay). Median myeloid and erythroid progenitors expanded 15-fold at 7 days (range, 7 to 43), 40-fold at 14 days (range, 18 to 470), 46-fold at 21 days (range, 0 to 118), and 21-fold at 28 days (range, 0 to 61). In a system using gas-permeable bags without exchange of media or cytokine, median progenitors expanded 13-fold at 7 days (range, 7 to 36), 14-fold at 10 days (range, 4 to 61), 14-fold at 12 days (range, 3 to 46), and 10-fold at 14 days (range, 1 to 35). Progenitor expansion less than 10-fold occurred in 8% of experiments at day 7, in 17% at day 10, in 43% at day 12, and in 50% at day 14. When autologous plasma, autologous plasma processed (removal of cryoprecipitate, centrifugation, then filtration), or human serum were substituted for 20% fetal calf serum, the ratio of progenitor expansion at 7 days relative to 20% fetal calf serum for 10% human serum, 20% human serum, and 1% autologous plasma processed was 1.01 (range, 0.62 to 1.33), 0.88 (range, 0.61 to 1.20), and 0.96 (range, 0.55 to 1.64), respectively. These findings support the feasibility of ex vivo expansion in a system free of nonhuman proteins of CD34(+)-derived progenitors obtained from the peripheral blood of patients who have received prior chemotherapy.

Reinfusion and serial measurements of carboplatin-mobilized peripheral-blood progenitor cells in patients receiving multiple cycles of high-dose chemotherapy.

To examine the ability of carboplatin to mobilize peripheral-blood progenitor cells (PBPCs) and to examine the impact of infusing these cells on myelosuppression following multiple cycles of high-dose therapy. Fluctuations in circulating progenitor cell concentration following repeated cycles of this therapy were also measured. Eight patients received a total of 20 cycles of carboplatin 1,200 mg/m2 per course, granulocyte-macrophage colony-stimulating factor (GM-CSF) 5 micrograms/kg/d, and PBPC reinfusion every 28 days. PBPC were collected following 1 week of GM-CSF and following the first and second cycles of chemotherapy. Hematologic toxicity was correlated with the number of progenitor cells reinfused per cycle. The concentration of PBPC per milliliter of blood was measured at study entry, following GM-CSF priming, and after each cycle of chemotherapy. We observed a strong inverse correlation between the number of PBPCs (CD34 and colony-forming unit granulocyte-macrophage [CFU-GM]), but not mononuclear cells (MNCs) reinfused and the days with neutropenia less than 500/microL and platelets less than 20,000/microL. Compared with baseline levels, the circulating PBPC concentration increased up to 27-fold following the first course of chemotherapy, but decreased toward, and eventually below, baseline following the second and third cycles of carboplatin. PBPC reinfusion directly correlated with a reduction in myelosuppression following high-dose carboplatin chemotherapy. While high-dose carboplatin plus GM-CSF leads to a substantially greater mobilization of PBPC than GM-CSF alone, this effect is lost after multiple treatment cycles. These results emphasize the importance of early procurement and value of PBPC reinfusion in conjunction with multiple cycles of dose-intensive chemotherapy.

Persistent problems of neutropenia and thrombocytopenia with peripheral blood stem cell transplantation.

We describe potential problems that may limit the usefulness of peripheral blood stem cells (PBSC) to facilitate the delivery of multiple cycles of high-dose chemotherapy. These include (1) cumulative myelotoxicity and (2) recurrent episodes of febrile neutropenia and a requirement for frequent platelet transfusions as a result of the stubborn persistence of a minimum of 7-9 days of absolute neutropenia and even longer durations of severe thrombocytopenia, despite utilization of PBSC. However, some of these problems may be overcome by shortening the duration of administration of the high-dose regimen with subsequent earlier reinfusion of the stem cell product. The adverse consequences of severe neutropenia could be overcome by the development of prophylactic neutrophil transfusions. These concepts are discussed with presentation of some preliminary data.

High-intensity chemotherapy with hematopoietic support in breast cancer.

Chemotherapy can produce excellent palliation for many patients with metastatic breast cancer. Survival impact is, however, limited, and permanent remission is extremely rare. There is increasing evidence that dose and dose intensity may be important determinants of outcome in the chemotherapy of breast cancer. Single courses of chemotherapy in doses requiring autologous bone marrow support produce high rates of objective response in patients with metastatic disease that was refractory to prior standard-dose therapy. When used as first chemotherapy for metastases or as consolidation in patients whose disease is responding to lower-dose therapy, high-dose chemotherapy can result in prolonged disease-free survival for some patients. The major cause of treatment failure is relapse from a chemotherapy-induced complete response. Kinetic models suggest that multiple, rapidly cycled courses of high-dose chemotherapy might be superior to single applications or to multiple treatments that are widely spaced in time. Heretofore, the substantial toxicity of high-dose chemotherapy (up to 20% mortality in some early trials) has largely precluded the consideration of timely retreatment; however, the risk appears to have been reduced through the use of hematopoietic growth factors and peripheral blood progenitor cells. Our group has used these new technologies to develop regimens consisting of multiple cycles of high-dose chemotherapy that are rapidly administered. We are currently refining these regimens in preparation for phase II and III studies.

Effects of Recombinant Human Granulocyte-Macrophage Colony-Stimulating Factor on Myelosuppression induced by Multiple Cycles of High-Dose Chemotherapy in Patients With Advanced Breast Cancer

In this study, 18 patients with advanced breast cancer were treated with multiple cycles of doxorubicin (75 or 90 mg/m2) plus cyclophosphamide (750 or 1000 mg/m2) every 21 days. Granulocyte-macrophage colony-stimulating factor (GM-CSF) (250 micrograms/m2 per day) was administered by continuous infusion during 10 days (days 2-12), starting in the first or second cycle of chemotherapy. Sixteen (89%) of 18 patients (95% confidence interval, 65%-99%) achieved an objective remission, five (28%) of which were complete. The median duration of response was 7 months. When GM-CSF was used for the first time, it had an effect on the kinetics of all blood cells, including neutrophils, lymphocytes, thrombocytes, and reticulocytes. However, in subsequent cycles of chemotherapy, the stimulatory effect of GM-CSF on hematopoiesis was substantially diminished. World Health Organization grade 3 and 4 neutropenia and thrombocytopenia necessitated dose reductions of doxorubicin and cyclophosphamide from cycle 2 onward in all patients treated with the highest dose. Side effects of GM-CSF included fever, general weakness, and hypotension. These toxic effects mimicked sepsis, and hospital admission for treatment with intravenous antibiotics was required for 73 days in 61 cycles of chemotherapy that included GM-CSF. Dose-intensive chemotherapy produced a high response rate in patients with advanced breast cancer. However, GM-CSF administered from day 2 to day 12 at a dose of 250 micrograms/m2.