Use of peripheral-blood progenitor cells abrogates the myelotoxicity of repetitive outpatient high-dose carboplatin and cyclophosphamide chemotherapy

Evaluation of a biosimilar granulocyte colony-stimulating factor (filgrastim XM02) for peripheral blood stem cell mobilization and transplantation: a single center experience in Japan

Background

Biosimilar granulocyte colony-stimulating factor (G-CSF) has recently been introduced into clinical practice. G-CSFs are used to mobilize CD34⁺ cells and accelerate engraftment after transplantation. However, in Asia, particularly in Japan, data for peripheral blood stem cell (PBSC) mobilization by this biosimilar G-CSF are currently lacking. Therefore, the clinical efficacy and safety of biosimilar G-CSF for hematopoietic stem cell transplantation needs to be evaluated in a Japanese context.

Materials and methods

The subjects included two groups of patients with malignant lymphoma and multiple myeloma. All patients received chemotherapy priming for the mobilization of PBSCs. All patients were treated with chemotherapy followed by the administration of either the biosimilar G-CSF, filgrastim XM02 (FBNK), or the originators, filgrastim, or lenograstim.

Results

There were no significant differences among FBNK, filgrastim, and lenograstim treatments in the numbers of CD34⁺ cells in harvested PBSCs, the scores for granulocyte/macrophage colony forming units, or for malignant lymphoma and multiple myeloma patients evaluated as separate or combined cohorts. In addition, there were no significant differences in safety, side effects, complications, or the time to engraftment after autologous hematopoietic stem cell transplantation.

Conclusion

Biosimilar FBNK shows the same efficacy and safety as originator G-CSFs for facilitating bone marrow recovery in Japanese malignant lymphoma and multiple myeloma patients undergoing stem cell transplantation. In addition, it is less expensive than the originators, reducing hospitalization costs.

Platelet Procoagulant Activity During,Peripheral Blood Stem Cell Harvest

We used flow cytometry to measure platelet-derived microparticle levels in plasma obtained from 16 patients during peripheral blood stem cell harvest (PBSC) and in platelet concentrates prepared by apheresis from 10 normal controls. We also studied the binding of an anti-P-selectin antibody and annexin-V to platelets. When all 60 harvests were assessed, we noted a significant difference in microparticle levels between patients with a platelet count >10 x 104/μl and those with a platelet count <10 X 104/μl (12.3 ± 4.4 vs. 75 ± 3.9%). In both the first and total harvests, the percentage of platelets and microparticles positive for anti-P-selectin and annexin-V were significantly higher than the normal control levels. These results suggest that patients undergoing mobilization by granulocyte colony-stimulating factor (G-CSF) who have a platelet count >10 X 104/μl are at risk of increased procoagulant activity after retransfusion following PBSC harvest. Key Words: Platelet-derived microparticle— Peripheral blood stem cell harvest—Granulocyte colony-stimulating factor.

The use of autologous peripheral blood stem cells as a hemopoietic support during polychemotherapy of children with soft tissue sarcomas

Intensification of cycle polychemotherapy in disseminated tumors considerably improves the efficiency of complex treatment. Reinfusion of peripheral blood stem cells as a factor of replacement treatment during hemopoietic suppression or disorders is now becoming more and more promising.

Peripheral blood stem cell support for multiple cycles of dose intensive induction therapy is feasible with little risk of tumor contamination in advanced stage neuroblastoma: a report from the Childrens Oncology Group

BACKGROUND

Poor outcome in Stage 4 neuroblastoma may be improved with increased dose intensity of therapy. We investigated the feasibility of sequential collection and infusion of peripheral blood stem cells (PBSCs) as hematopoietic support for non-myeloablative dose intensive induction chemotherapy given every 21-28 days.

METHODS

Twenty-two children with Stage 4 neuroblastoma (>or=1 year of age) received two cycles of high-dose cyclophosphamide (4 g/m(2)), doxorubicin (75 mg/m(2)), and vincristine (2 mg/m(2)) followed by three cycles of interpatient dose escalating carboplatin (Dose Level 0 = 800 mg/m(2); Dose Level 1 = 1,000 mg/m(2)), high-dose cyclophosphamide (4 g/m(2)), and etoposide (600 mg/m(2)). PBSC were harvested following cycle 2, 3, and 4 in Cohort 1 and infused after each subsequent cycle. In Cohort 2, PBSC were harvested after cycle 2 and split into three aliquots for infusion. Dose limiting toxicity (DLT) and ability to administer cycles within 28 days was assessed.

RESULTS

Sufficient PBSC (>or=2 x 10(6) CD34 cells/kg per infusion) were collected from 17/21 eligible patients with minimal toxicity and no detectable neuroblastoma cells by immunocytology. Carboplatin at 1000 mg/m(2) resulted in DLT of delayed platelet recovery >28 days in 4/8 patients. Despite de-escalation to 800 mg/m(2), platelet DLT occurred in 4/7 Cohort 1 and 3/7 Cohort 2 patients.

CONCLUSION

As defined in this protocol, doses of carboplatin were not tolerable with the PBSC dose administered. However, it was feasible to collect sufficient PBSC from small neuroblastoma patients to use as hematopoietic support with minimal risk of tumor contamination and toxicity.

Leukapheresis after high-dose chemotherapy and autologous peripheral blood progenitor cell transplantation: a novel approach to harvest a second autograft

BACKGROUND

Autologous peripheral blood progenitor cells (PBPCs) are usually collected after the administration of conventional-dose chemotherapy (CDCT) and growth factors. However, there are no data available concerning the collection of PBPCs after high-dose chemotherapy (HDCT) and autologous hematopoietic transplantation in a larger series.

STUDY DESIGN AND METHODS

Patients (n = 30) underwent leukapheresis for PBPC harvest after CDCT. After HDCT and autografting, the collection of a second PBPC autograft was attempted.

RESULTS

Leukapheresis was performed after CDCT in all cases at a median of 118 CD34+ cells per microL (range, 18-589) and resulted in 6.4 x 10(6) CD34+ cells per kg (range, 1.7-29.0). After HDCT and autografting, 24 patients (80%) underwent secondary leukapheresis, although they had a significantly lower median of peripheral blood (PB) CD34+ cells (30/microL; range, 10-171; p < 0.001). In these patients a median of 3.6 x 10(6) CD34+ cells per kg (range, 1.6-10.1) was collected in the post-transplantation course. In the remaining six patients (20%) with PB CD34+ cells < 10 per microL, no PBPC harvesting was performed. These so-called poor mobilizers had received significantly less CD34+ cells for autologous transplantation than patients with successful post-HDCT mobilization (median, 2.5 x 10(6)/kg [range, 1.7-3.0] vs. 6.5 x 10(6)/kg [range, 3.2-19.6]; p < 0.001).

CONCLUSION

Collection of PBPCs is possible in most patients during the recovery phase of hematopoiesis after HDCT plus autografting, and the number of circulating PBPCs may be related to the CD34+ cell dose transfused by the preceding autograft.

Pilot evaluation of high-dose carboplatin and paclitaxel followed by high-dose melphalan supported by peripheral blood stem cells in previously untreated advanced ovarian cancer: a gynecologic oncology group study

OBJECTIVES

To evaluate the efficacy and safety of multiple cycles of high-dose carboplatin and paclitaxel and one consolidation cycle of high-dose melphalan with all cycles supported by hematopoietic stem cells and cytokine, in previously untreated patients with optimally debulked stage III epithelial ovarian cancer.

PATIENTS AND METHOD

Patients had histologically documented epithelial ovarian cancer and optimal initial cytoreductive surgery. No prior chemotherapy was permitted. Adequate performance status, bone marrow, hepatic, and renal function was required. After being mobilized with cyclophosphamide 3 g/m(2), paclitaxel 300 mg/m(2), and filgrastim 5 microg/kg/day, peripheral blood stem cells (PBSC) were collected by leukapheresis. Patients received three cycles of carboplatin AUC 15 mg. min/ml iv, paclitaxel 250 mg/m(2), and PBSC with filgrastim every 28 days, followed by one cycle of melphalan 140 mg/m(2) and hematopoietic support.

RESULTS

Nine patients entered the trial and received all planned cycles of chemotherapy. Of the eight patients who consented to surgical reassessment upon completing therapy, four had residual small-volume macroscopic disease, three had microscopic residual disease, and one had pathologic complete response. The estimated probability of a pathologic complete response was 12.5% (95% confidence interval: 0.3-52.7%). Hematologic toxicity was severe but manageable. Eleven of 45 cycles (24.4%) resulted in hospital admission for neutropenic fever, dehydration +/- diarrhea, syncope, or shortness of breath and pain secondary to tense ascites.

CONCLUSIONS

The low pathological complete response rate did not justify toxicity; thus, the study was closed. High-dose chemotherapy as first-line treatment for epithelial ovarian cancer remains experimental and should be restricted to clinical trials.

A dose escalation study for salvage chemotherapy in patients with refractory lymphoma prior to high-dose myeloablative therapy with stem cell transplantation

Chemosensitive response prior to transplantation has been shown to be most significant for survival post transplant. To estimate toxicity of a dose-intensive regimen that was to improve chemosensitive response rate, 15 patients with primary refractory lymphoma were enrolled in dose escalation of pre-transplant salvage chemotherapy. The first cycle had a fixed dose of ifosfamide 6 g/m2 and mitoxantrone 12 mg/m2, with arabinosyl cytosine (Ara-C) 2 g/m2, and methylprednisolone 2.0 g. Each cycle of the second and third had cisplatin 90 mg/m2, Ara-C 6 g/m2, methylprednisolone 2.0 g, and escalated doses of ifosfamide from 7.5 g/m2 to 15 g/m2 and mitoxantrone from 16 to 28 mg/m2. Blood stem cells were collected before the second cycle and > or = 3 x 10(6) CD34 cells/kg were infused 2 days after the second and third cycles, respectively. The maximum tolerated doses of ifosfamide and mitoxantrone were 11.25 g/m2 and 16 mg/m2, respectively. Acute renal failure and bacterial infection occurred as non-hematologic dose limiting toxicities. Eleven patients completed therapy. Five patients achieved complete remission and five had partial remission. Nine patients received autologous and four received allogeneic transplants. Currently, six are alive without evidence of disease, with a 3-year survival of 40%. Although preliminary, the regimen suggests acceptable toxicity and significant activity that warrants further study.

Phase II trial of high-dose intravenous doxorubicin, etoposide, and cyclophosphamide with autologous stem cell support in patients with residual or responding recurrent ovarian cancer

This study was performed in order to evaluate the toxicities, progression-free and overall survival of patients with responsive residual or recurrent ovarian cancer treated with high-dose chemotherapy. Twenty-seven patients were treated. Doxorubicin, 165 mg/m(2) over 96 h (days -12 to -8), etoposide 700 mg/m(2) every day x3 (days -6 to -4), and cyclophosphamide 4.2 g/m(2) on d -3 was followed by stem cells and granulocyte colony-stimulating factor. The median days of granulocyte count <500/microl was 14 (range 10-42) and platelets <20,000/microl was 13 (range 2-80). Median numbers of red cell and platelet transfusions were 15 (5-16) and 14 (4-103). Toxicity included mucositis requiring narcotic analgesia in all patients. Asymptomatic decreases in ejection fraction to values <50% were observed in four patients. No clinical congestive heart failure was observed. One death due to sepsis was observed. Median progression-free survival is 7.5 months (1.0-56 months); five patients remain alive, two of whom remain progression-free at 19.5 and 24.5 months post transplant. Median overall survival is 14.0 months (1-68 months). We conclude that high-dose anthracyclines may be safely administered to ovarian cancer patients. The short overall and progression-free survivals observed in our population suggest that this combination is not optimal.

A phase I dose escalation study of multicyclic, dose-intensive chemotherapy with peripheral blood stem cell support for small cell lung cancer

A phase I dose-escalation study of multicyclic, ifosfamide, carboplatin, and etoposide (ICE) with sequential reinfusion of peripheral blood stem cells (PBSCs) was conducted to determine the maximum-tolerated dose (MTD) of ICE. Twenty-four patients with SCLC (LD: 6, ED: 18) were treated with ifosfamide (3000-9000 mg/m2, 24-h infusion), carboplatin (300-400 mg/m2), and etoposide (300 mg/m2) followed by subcutaneous filgrastim (75 microg/day) from day 4 to the day of PBSC collection. PBSC were harvested when the WBC count reached >/=5 x 109/l. The leukapheresis product was cryopreserved and reinfused on day 4 of the next cycle, which was started 48 h after the last PBSC collection. The ifosfamide dose was escalated as follows: 3000 mg/m2 (level 1), 5000 mg/m2 (level 2), 7000 mg/m2 (level 3), 9000 mg/m2 (level 4). Patients with LD were treated with concurrent radiotherapy at 1.5 Gy twice daily for the initial 3 weeks to a total dose of 45 Gy and MTD, defined separately. Patients were evaluated for hematologic and non-hematologic toxicity, actual dose intensities, as well as response to therapy. The maximum-tolerated dose (MTD) was defined as the dose level at which more than 5 days of grade 4 myelo- suppression or non-hematologic toxicity greater than grade 3 developed in two thirds of the patients. For ED cases, MTD was level 4 and the recommended dose of ifosfamide was 7000 mg/m2. For LD cases, the recommended dose of ifosfamide was 5000 mg/m2. The dose limiting toxicity of multicyclic ICE was hemato- logic toxicity and CNS toxicity which manifested as ataxia. Tumor responses were seen in all patients, with 14 patients showing a complete response. The actual total dose-intensity at the recommended dose level was 2.2 and 1.74, for ED and LD, respectively, compared with previously reported ICE regimens. PBSC support for dose-intensive ICE regimen permitted dose escalation of ifosfamide with a mean interval of 16-17 days. We conclude that this regimen is well tolerated, with acceptable hematological and non-hematological toxicity. Bone Marrow Transplantation (2000) 25, 5-11.

Phase II trial of induction high-dose chemotherapy followed by surgical resection and radiation therapy for patients with marginally resectable non-small cell carcinoma of the lung

The combination of carboplatin and paclitaxel is an active regimen in non-small cell lung cancer (NSCLC). Historically, patients with stage III disease have manifested higher response rates than patients with metastatic disease, and patients achieving a pathologic complete response to induction chemoradiation therapy prior to surgery have shown better long-term outcome. Based upon our pilot data using high-dose carboplatin and paclitaxel, we designed a phase II trial in patients with marginally resectable stage IIIA NSCLC. Ten patients, with bulky nodal stage IIIA disease, initially received etoposide (2 g/m2) and granulocyte colony-stimulating factor (G-CSF) to mobilize peripheral blood stem cells (PBSC). Two cycles, 28 days apart, of carboplatin (AUC 12 in seven patients; AUC 16 in three patients) and paclitaxel (250 mg/m2) were administered with filgrastim (5 microg/kg) and PBSC support. After re-evaluation, patients underwent a thoracotomy followed by radiotherapy (44-60 Gy) if deemed resectable, or radiotherapy alone (60 Gy) if not resectable. The median age was 58.5 years (48-66) with a median ECOG performance status of 0 (0-1). Histology was adenocarcinoma in seven patients; the remainder had either squamous cell, large cell or bronchoalveolar carcinoma. Based on CT radiography, the overall response rate was 40%. Eight of ten patients underwent resection with four right pneumonectomies, three right upper lobectomies and one wedge resection of the right upper lobe. Six patients had a complete resection. Of eight patients resected, four were downstaged by induction therapy, three remained unchanged and one was found to have more extensive disease. The remaining two patients developed metastatic disease while receiving chemotherapy. The median dose of postoperative radiotherapy was 54 Gy (35-66 Gy). Actual median follow-up for all patients was 89 weeks (25 to 136+). The actuarial median overall survival was 124 weeks (25 to 136+) and time to progression was 57 weeks (17 to 136+). The median dose of carboplatin delivered expressed as mg/m2 was 779 (615-1540). Neutropenic fever occurred in two patients during the initial mobilization cycle only. The median number of units of RBC and/or platelets transfused was 0 (0-2 and 0-6, respectively). There were no significant non-hematologic toxicities. High-dose induction chemotherapy with stem cell rescue is feasible and safe with an acceptable response rate. Thoracotomy, including pneumonectomy and postoperative radiotherapy, were well tolerated by patients after undergoing high-dose induction chemotherapy with no apparent increase in peri-operative morbidity. The pathologic complete response rate was low--one out of ten patients. These results indicate that dose escalation of induction chemotherapy does not improve response rates even in this highly selected patient population. Accordingly, the complexity and potential toxicity of high-dose chemotherapy, as delivered in this trial as neoadjuvant treatment of non-small cell lung cancer, is not warranted.

Hematopoietic stem cell transplantation for small cell lung cancer

Treatment for small cell lung cancer has not improved substantially in the past 15 years. Some advances are being made in supportive care and by use of more intense concurrent thoracic radiotherapy. New agents such as the taxanes and the topoisomerase I inhibitors hold promise and are currently in phase III evaluation. The question whether dose intensity can improve the outcome of patients with small cell lung cancer has been raised for many years. Improving supportive care enhances our ability to test this question more thoroughly. This paper reviews the historical and current experience using high-dose therapy with hematopoietic stem cell support for the treatment of small lung cancer. Future directions are identified.

Dose-intensive therapy for limited-stage small-cell lung cancer: long-term outcome

PURPOSE

To determine progression-free survival (PFS) and overall long-term survival for limited-stage small-cell lung cancer (SCLC) patients aged 60 years or younger who respond to first-line chemotherapy followed by high-dose combination alkylating agents (cyclophosphamide 5,625 mg/m(2), cisplatin 165 mg/m(2), and carmustine 480 mg/m(2)) with hematologic stem-cell support and chest and prophylactic cranial radiotherapy.

PATIENTS AND METHODS

Patients were selected on the basis of their continued response to first-line therapy, their relative lack of significant comorbidity, and their ability to obtain financial clearance.

RESULTS

Of 36 patients with stage III SCLC, nine patients (25%) had achieved a complete response (CR), 20 had achieved a near-CR, and seven had achieved a partial response before undergoing high-dose therapy. Toxicity included three deaths (8%). For all patients, the median PFS was 21 months. The 2- and 5-year survival rates after dose intensification were 53% (95% confidence interval [CI], 39% to 72%), and 41% (95% CI, 28% to 61%). Of the 29 patients who were in or near CR before undergoing high-dose therapy, 14 remain continuously progression-free a median of 61 months (range, 40 to 139 months) after high-dose therapy. Actuarial 2- and 5-year PFS rates were 57% (95% CI, 41% to 79%) and 53% (95% CI, 38% to 76%). By multivariate analysis, short intensive induction chemotherapy was associated with favorable outcome (P <.05).

CONCLUSION

Use of high-dose systemic therapy with intensive local-regional radiotherapy was associated with manageable treatment-related morbidity and mortality. Patients who were in or near CR before intensification are enjoying an unmaintained 5-year PFS rate of 53%. Late complications were infrequent, and most patients returned to full-time work and activity. A randomized comparison of this approach and conventional-dose therapy should define the use of dose intensification with hematopoietic support in patients with responding limited-stage SCLC.

Dose-Intensified Chemotherapy for Breast Cancer: Present and Future Prospects

With the trend to maximize chemotherapy in breast cancer, the use of peripheral blood stem cells in addition to hematopoietic growth factors to alleviate myelosuppression caused by dose-intensified chemotherapy has been shown to be beneficial. In treatment of metastatic breast cancer, response rates and complete response rates as high as 100%and nearly 80%, respectively, have been reported. Such treatments have shown even greater promise in an adjuvant setting for high-risk breast cancer. High-dose chemotherapy studies, however, involve highly-selected patient populations who are generally compared with unselected patients, and controversy still surrounds the question of whether it is substantially superior to conventional-dose chemotherapy. There are now more than sufficient data to justify ongoing randomized trials, and the most important overall recommedation is to encourage patients to participate in these clinical trials.

Conditioning regimens before transplantation in patients with aggressive non-Hodgkin's lymphoma

Substantial progress has been made in understanding the role of autotransplantation in aggressive non-Hodgkin's lymphoma. At present, the clinical indications for high-dose therapy include patients with relapsed or poor prognosis disease. Hematopoietic reconstitution with peripheral stem cells has rendered transplantation less toxic but the optimal preparative regimen remains to be found. It should combine a high antitumor activity with acceptable toxicity to normal tissues. The literature, on combinations of drugs with or without total body irradiation, was reviewed with regard to this objective. BEAM, CBV and ICE, the most common chemotherapy regimens can be considered safe as they cause low transplant-related morbidity. The combination of fractionated TBI and etoposide or cyclophosphamide was not found to be superior. However, it must be kept in mind that comparisons were made on registry data or retrospectively. In every case, relapse of the residual primary disease argue for the need for more effective strategies such as tandem transplantation or sequential high-dose chemotherapy with stem-cell support. To obtain an objective evaluation, these new preparative regimens need to be tested in controlled trials with treatment groups stratified for known prognostic factors.

A proof of glutathione S-transferase-pi-related multidrug resistance by transfer of antisense gene to cancer cells and sense gene to bone marrow stem cell

In order to directly prove the involvement of GST-pi in drug resistance, it's antisense gene was transduced into human colorectal cancer cell line which has been shown to express high level of GST-pi and the sensitivity of this cell line to anticancer drugs were assessed. The transfectant showed higher sensitivity to adriamycin (3.3-fold), Cisplatnum (2.3-fold), Melphalan (2.2-fold), Etoposode (2.2-fold) than the parental cell, while the sensitivity to vincristine, mitomicin C, 5-fluorouracil was unchanged by transfection. When the transfectant and parental cells were innoculated in nude mice and treated with adriamycin, a significant suppression of tumor growth was observed with the transfectant as compared to the parental cell. On the basis of this observation, we then transduced sense GST-pi gene into human bone marrow stem cells (CD34+ cells) to protect them from toxicity of anticancer drug. The gene transduced CD34+ cells formed more CFU-GM than nontransduced CD34+ cell in the presence of adriamycin (30 ng/ml). Thus, the autotransplantation of GST-pi gene transduced cell into cancer patients to protect the bone marrow from subsequent highdose chemotherapy is considered to be a new strategy for cancer gene therapy.

Dose-intensive therapy in small cell lung cancer

Basic to curative treatment for small cell lung cancer (SCLC) are the principles of dose response, combination chemotherapy, and combined-modality therapy. Theory and experimental and clinical data suggest that solid tumors recur, despite initially responding to chemotherapy due to drug resistance. Resistance to chemotherapy is potentially overcome by using 5- to 10-fold higher doses. To decrease the emergence of drug resistance, combinations of active non-cross-resistant agents are used. Hematopoietic stem cell support provides the opportunity to test dose response to the limits of organ tolerance. Dose-intensive therapy for lung cancer patients is complicated by the fact that this disease most often occurs in an older-aged population (median, 60 to 65 years) with underlying smoking-related comorbid disease, early metastatic spread, and enhanced risk of secondary smoking-related malignancies. In a phase II feasibility trial just activated, patients younger than 60 years of age with limited-stage SCLC are being treated with four cycles of cisplatin and etoposide and concurrent twice-daily chest radiotherapy to 45 Gy (150-cGy fractions). Those patients achieving complete or near-complete response will receive high-dose cyclophosphamide/cisplatin/ carmustine with autologous stem cell support. Upon recovery, prophylactic cranial irradiation will be given. Results could lead to a phase III trial testing the concept of dose intensification. This article reviews evidence for the contribution of dose intensification to response and survival in the treatment of SCLC, the adequacy of the clinical trial's design to address these relationships, and suggestions for future directions. The strategies of dose-intensive induction therapy, multicycle dose-intensive combination therapies, chest radiography, and stem cell purging trials will be discussed.

Feasibility of sequential high-dose chemotherapy and peripheral blood stem cell support for pediatric central nervous system malignancies

BACKGROUND

The outlook for many brain tumors remains poor. Increased dose intensity has been correlated with response rate and survival in many solid tumors.

PATIENTS AND METHODS

Ten children with recurrent or newly diagnosed brain tumors were treated with four sequential courses of high-dose single agent chemotherapy with peripheral blood stem cell (PBSC) support. PBSC harvesting was undertaken prior to chemotherapy and following the first course of chemotherapy (3.6 g/m2 etoposide). Each course of chemotherapy consisted of a single drug followed 48 hours later by PBSC reinfusion. Three patients were treated on Regimen A: etoposide, carboplatinum 1.95 g/m2, cyclophosphamide 5 g/m2, and thiotepa 300 mg/m2; three patients were treated on Regimen A' with carmustine 600 mg/m2 replacing cyclophosphamide; four patients received Regimen B: etoposide, carboplatinum 1.95g/m2, cyclophosphamide 7 g/m2, and thiotepa 900 mg/m2.

RESULTS

No course of chemotherapy was complicated by >14 days of neutropenia. Platelet recovery was more prolonged, particularly in patients who had previously received craniospinal irradiation. Non-hematologic toxicity was severe with three toxic deaths including two patients who developed hemolytic-uremic syndrome and respiratory failure. Two of three patients with primitive neuroectodermal tumors had a partial response; no responses were observed in patients with high-grade gliomas.

CONCLUSIONS

Administration of multiple courses of high-dose chemotherapy with PBSC support is feasible in this patient population and successfully mitigates hematologic toxicity. Non-hematologic toxicity becomes prohibitive as chemotherapy doses are escalated.

Cycles of dose-intensive chemotherapy with peripheral stem cell support in persistent or recurrent platinum-sensitive ovarian cancer

OBJECTIVE

The objective was to determine the toxicity and surgically documented response rate of sequential high-dose chemotherapy with peripheral stem cell support in patients with persistent or recurrent cisplatin-sensitive ovarian cancer.

METHODS

Fourteen patients (average age, 45 years) were treated with cyclophosphamide (4.5 g/m2), followed by granulocyte colony-stimulating factor (G-CSF)-stimulated peripheral stem cell harvests. The subsequent regimen prescribed three courses of carboplatin (1 g/m2) and cyclophosphamide (1.5 g/m2 with 2-mercaptoethanesulfonate) every 2 weeks with stem cell support. This was followed by three courses of paclitaxel at 250 mg/m2 every 2 weeks with G-CSF support only. Six patients were entered on the basis of a positive second-look laparotomy and 8 patients had a first recurrence after at least a 6-month disease-free interval.

RESULTS

Fourteen patients were entered and 12 patients completed all planned courses of therapy (mean time, 13 weeks). Normal hematopoiesis was reestablished after each cycle. Hospitalization for neutropenic fever occurred in 11/93 cycles (11.8%). Thirteen patients required blood transfusions and in 12 patients platelet transfusions were given. One patient had grade 3 neurotoxicity. An initial elevated CA 125 returned to normal in 7/8 patients (88%) and 71% of patients with measurable disease responded to therapy. There were 2 pathologic complete responders (PCR), making the PCR rate 2/14 or 14% (0-35%).

CONCLUSION

Although this regimen was well tolerated and clinical response rates were high, the surgically documented response rate was not clearly superior to conventional salvage regimens in platinum-sensitive patients.

Peripheral blood stem cell transplantation

High dose chemo/radiotherapy requiring autologous haemopoietic stem cell support is increasingly used in a variety of malignant disorders. Mobilised peripheral blood stem cells (PBSC) have largely replaced the use of autologous bone marrow due to more rapid haemopoietic reconstitution with less resource use including blood and platelet transfusion requirements. PBSC graft adequacy is monitored by CD34+ cell and granulocyte-monocyte-colony-forming-cell measurements, and thresholds for rapid engraftment have been determined. Studies are in progress to determine the optimal mobilisation regimens that will permit the achievement of the necessary progenitor thresholds with only one or two aphereses. This will facilitate the use of multiple cycles of high dose therapy and possibly the use of PBSC collected by venesection rather than apheresis. PBSC are also increasingly used in the allogeneic setting where specific mobilisation protocols not using cytotoxic drugs are employed. These technical advances will aid the execution of large trials to determine the efficacy of high dose therapy.

Fibronectin fragment-facilitated retroviral transfer of the glutathione-S-transferase pi gene into CD34+ cells to protect them against alkylating agents

To protect bone marrow cells from the toxicity of chemotherapy, a multidrug resistant gene or a dihydrofolate reductase gene has been introduced into stem cells. These genes, however, are not capable of conferring refractoriness to alkylating agents (AA), which are some of the most commonly used agents in chemotherapy regimens. In the present study, an attempt was made to endow human stem cell (CD34+ cells) with resistance to cyclophosphamide, a well-known AA, and adriamycin (ADM) by transducing the glutathione-S-transferase pi (GST-pi) gene whose product is thought to detoxify AA by conjugating them with glutathione and to remove a toxic peroxide formed by ADM. The gene transduction was carried out retrovirally with a virus titer of 1 x 10(5) FFU/ml, employing a recombinant fibronectin fragment; transduction efficiency was extremely low without the fragment. Incubation with interleukin-6 and stem cell factor enhanced the expression of fibronectin ligands VLA4 and VLA5 on CD34+ cells. This enhanced expression of VLA4 and VLA5 was considered to facilitate a close contact of the CD34+ cell to the retroviral vector via fibronectin fragments and the subsequent transduction process. The GST-pi gene-transduced CD34+ cells formed almost 3- and 2.5-fold more CFU-GM than neo gene-transduced CD34+ cells in the presence of 2.5 microg/ml of 4-hydroperoxycyclophosphamide (4-HC), an active form of cyclophosphamide, and 30 ng/ml ADM, respectively. The transfectants formed an appreciable number of colonies, even at higher concentrations of these drugs (5.0 microg/ml of 4-HC, 50 ng/ml of ADM) whereas neo gene-transduced or nontransduced CD34+ cells formed no colonies at all, indicating the possibility of selecting out the transfectants by exposing them to these anticancer drugs. Thus, we were able to demonstrate that transduction of the GST-pi gene confers resistance to cyclophosphamide as well as to ADM, and therefore this approach can be applied clinically for high-dose chemotherapy.

High dose cyclophosphamide with carboplatin: a tolerable regimen suitable for dose intensification in children with solid tumors

PURPOSE

To determine the hematopoietic and nonhematopoietic toxicity of a novel dose-intensive chemotherapy regimen for the treatment of children with relapsed solid tumors.

PATIENTS AND METHODS

The time to hematopoietic recovery and toxicity experienced during 46 courses of high-dose cyclophosphamide (4.0 g/m2), MESNA, and carboplatin (400 mg/m2) with granulocyte colony stimulating factor (G-CSF) support in 14 children with recurrent solid tumors was reviewed.

RESULTS

All patients developed grade 4 neutropenia and thrombocytopenia. Recovery to an absolute neutrophil count (ANC) of 500/microliter and platelet count of 50,000/microliter occurred at a median of 15 days and 23 days respectively. Median time to ANC > 1,000/microliter and platelets > 100,000/microliter was 27 days. Hospitalization for fever and neutropenia occurred during 35 of 46 courses, with documented bacteremia in six courses. There was no grade II or greater nonhematopoietic organ toxicity. Responses (CR + PR) were observed in 6 of 11 evaluable patients.

CONCLUSIONS

These data suggest that this regimen is tolerable in heavily pretreated children with solid tumors with myelosuppression as the primary toxicity. Due to the lack of significant nonhematopoietic toxicity, this is a good candidate regimen for dose escalation using peripheral blood progenitor cell infusions and deserves further evaluation for efficacy in children with both recurrent and newly diagnosed high-risk solid tumors.

Prognostic parameters for survival of patients with malignant mesenchymal tumors of the uterus

BACKGROUND

Malignant mesenchymal uterine neoplasms are the most aggressive type of primary uterine tumors, with most patients dying within a few years of diagnosis. Thus, it would be very important to define prognostic factors for predicting the malignancy potential of at least some of their subtypes.

METHODS

Flow cytometric cell cycle analysis (proliferative activity, DNA ploidy, and DNA index) was performed on archival paraffin embedded blocks from 80 patients with malignant mesenchymal uterine neoplasms (endometrial stromal sarcomas, malignant smooth muscle tumors, and malignant Müllerian mixed tumors). The Cox proportional hazards regression model was used to assess relative effects of the following factors on patient survival: clinical stage, mode of therapy, DNA+proliferative activity, DNA index, histologic type, cellularity, degree of atypia, mitotic activity, and depth of myometrial invasion.

RESULTS

There were 9 low grade stromal sarcomas, 17 high grade stromal sarcomas, 8 smooth muscle neoplasms with uncertain malignant potential, 23 leiomyosarcomas, and 16 homologous and 7 heterologous malignant Müllerian mixed tumors. In univariate analysis for stromal sarcomas, statistical significance was found for DNA ploidy+proliferative activity (P < 0.001), histologic type (P = 0.005), and DNA index (P < 0.001). In multivariate analysis, DNA index appeared to be the only significant parameter influencing patient survival (P = 0.005). In univariate analysis for malignant smooth muscle neoplasms, statistical significance was detected for mitotic activity (P = 0.049) and International Federation of Gynecology and Obstetrics classification (P = 0.021), but in multivariate analysis, clinical stage appeared to be the only significant parameter influencing patient survival (P = 0.032). In univariate analysis for malignant Müllerian mixed tumors, statistical significance was found for the depth of myometrial invasion (P = 0.039), DNA index (P = 0.037), and clinical stage (P = 0.013), but in multivariate analysis, only the depth of myometrial invasion (P = 0.036) and clinical stage (P = 0.025) were of statistical significance.

CONCLUSIONS

The most powerful prognostic indicator for stromal sarcomas was the DNA index, for malignant smooth muscle neoplasms it was the clinical stage, and for malignant Müllerian mixed tumors it was the depth of myometrial invasion.

The contribution of animal models to the development of treatments for hematologic recovery following myeloablative therapy: a review

This review describes the role that animal models have played in the development of clinical procedures for growth factor and hematopoietic cell therapies following high-dose cancer chemotherapy, radiotherapy or both. Data are discussed describing animal models that add to the understanding of human hematopoiesis, including myeloid and lymphoid lineage localization and in vivo maturation. Finally, current animal models of cytokine and cell therapies are presented in the context of their contributions to early clinical trials and future therapies. These studies underscore the past and current contributions animal investigations have made to improving clinical therapies.

Impaired stem cell collection by consecutive courses of high-dose mobilizing chemotherapy using cyclophosphamide, etoposide, and G-CSF

Tandem cycles of myeloablative chemotherapy can increase dose intensity and total dose of chemotherapy, but sufficient numbers of progenitor cells must be collected to ensure hematologic recovery after each treatment. This study was undertaken to determine if two courses of mobilizing chemotherapy given 4 weeks apart using cyclophosphamide 4000 mg/m2 and etoposide 400 mg/m2, combined with G-CSF 5-10 mg/kg on days 3-16 could each provide sufficient numbers of peripheral blood progenitor cells to support tandem cycles of myeloablative chemotherapy in 20 patients with stage IV breast cancer. Leukapheresis of blood with WBC > 1000/mm3 was performed daily for up to five collections (days 12-16), and mononuclear cells, CFU-GM, and CD34+ cells were compared between the first and second collections. The second course of mobilizing treatment resulted in similar numbers of mononuclear cells collected but far fewer CFU-GM and CD34+ progenitor cells. This prevented using the second collection of progenitor cells as the sole source for the second transplant. The data suggest that a second course of cyclophosphamide, etoposide, and G-CSF given 4 weeks after the first leads to progenitor cell depletion, and efforts to increase the yield of blood-derived progenitors should focus on the initial mobilizing procedure.

Peripheral blood progenitor cell transplantation: a replacement for marrow auto- or allografts

Circulating hematopoietic progenitor cells include pluripotent stem cells expressing indefinite self-renewal capacity and, therefore, can be used for restoring hematopoiesis following myeloablative treatment. A transient shifting of progenitor cells from extravascular sites into the circulation by chemopriming and/or cytokine treatment enables the collection by apheresis of a sufficient number of progenitor cells to guarantee engraftment. The addition of new cytokines (e.g., thrombopoietin) and large volume apheresis will increase peripheral blood progenitor cell (PBPC) procurement efficiency, whereas the risk of concurrently mobilizing clonogenic tumor cells in patients with solid tumors and hematologic malignancies remains to be carefully evaluated. As compared with bone marrow (BM) progenitor cells, the use of PBPCs significantly shortens the recovery of WBC and platelets following transplantation. Most recently, successful allogeneic transplantation of PBPCs has been reported without increasing the incidence and severity of acute graft-versus-host-disease. Due to the more than one log higher number of lymphoid subsets contained in a PBPC allograft, one might expect a more pronounced graft-versus-leukemia effect in the transplant patient. Similar to BM cells, ex vivo manipulation of mobilized apheresis products is used or being developed (ultralight density percoll gradient, CD8 depletion, selection of graft facilitating cells, CD34+ cell purification and others). The transduction and long-term expression of marker genes and, most recently, therapeutic genes (e.g., MDR-1) in PBPCs have been successfully demonstrated by several groups in patients with hematologic malignancies and selected solid tumors. It is expected that, based on the easier procurement of hematopoietic stem cells and advantageous engraftment characteristics, PBPCs in both autologous and allogeneic transplant situations will eventually replace BM-derived progenitor cells.

Blood stem cell transplantation and gene therapy of cancer

Based on the concept of circulating hematopoietic stem cells with indefinite self-renewal capacity that gives rise to all three cell lineages, peripheral blood progenitor cells (PBPCs) have widely replaced the use of bone marrow (BM) progenitors for autologous transplantation purposes in patients with malignant hematological disorders and selected solid tumors. Ex vivo purification of normal CD34+ cell subsets contained in the patient's apheresis product possibly eliminates clonogenic tumor cells, but also serves as a target cell population for gene transduction. Genetic tagging of PBPC autografts has proven that: 1) NEOR gene expression is sustained for more than 18 months and 2) clonogenic tumor cells contaminating the autograft contribute to relapse. A second generation of gene transduction studies includes new treatment strategies such as the induction of chemoprotection (multidrug resistance gene-1), chemotherapy sensitization (p53), cancer vaccination and genetic chemosensitization. Most recently allogeneic PBPC transplantation has successfully been introduced with the intention of improving the graft-versus-leukemia effect without inducing a higher incidence or more severe graft-versus-host disease (GVHD) than what is expected after BM transplantation. Introducing the herpes virus thymidine kinase cDNA into activated donor T cells makes them susceptible to gangciclovir, thus allowing the in vivo inactivation of GVHD-inducing T cells. With the close interaction of molecular genetics and clinical oncology/hematology, genetic engineering of stem cell grafts will lead into a new stage of stem cell transplantation technology.

Very high-dose chemotherapy with autologous peripheral stem cell support in advanced ovarian cancer

20 patients with stage III-IV ovarian cancer were submitted to induction chemotherapy (ICT) (40 mg/m2 cisplatin, days 1-4; 1.5 g/m2 cyclophosphamide, day 4; every 4 weeks for 2 cycles) followed by intensified CT (100 mg/m2 cisplatin, day 1; 650 mg/m2 etoposide, day 2; 1.8 g/m2 carboplatin by 24 h infusion, day 3). Haematological support consisted of autologous peripheral stem cells (APSC) and bone marrow (ABM) transplant (T) in 16 and 4 patients, respectively. All patients were evaluable for toxicity and 19 for pathological response (PR), one patient dying of systemic mycosis after ABMT. Severe (grade 3-4) non-haematological toxic effects were gastrointestinal (100%), neurological (10%) and hepatic (10%). PR was observed in 84% of patients (complete response 37%, partial response with microscopic residual disease 26%, partial response with macroscopic residual disease 21%). Five year overall survival was 60% and progression-free survival was 51% with 9 patients still disease-free (DFS). APSCT significantly reduced the duration of aplasia compared with ABMT, and toxicity was acceptable in those patients undergoing APSCT. The prolonged DFS in patients showing PCR suggests that this new approach may have a therapeutic impact.

High-dose chemotherapy with stem cell reinfusion and growth factor support for solid tumors

With the help of stem cell reinfusion and hematopoietic growth factors, it is possible to get up to a ten-fold dose increase for certain chemotherapeutic drugs. A number of reasons may have made high-dose chemotherapy less dangerous and therefore more acceptable in a more upfront treatment setting. One of these is the addition of peripheral stem cell harvest obtained after mobilization with a hematopoietic growth factor alone or after chemotherapy followed by a hematopoietic growth factor, which seems to result in a faster recovery of neutrophils and platelets compared to bone marrow reinfusion alone. The combination of various hematopoietic growth factors could potentially improve hematopoietic recovery of the high-dose chemotherapy regimen. The relevance of tumor cells sometimes present in the reinfused hematopoietic stem cells is as yet unknown. High-dose chemotherapy may be interesting for a number of solid tumors such as nonseminomatous testicular carcinoma, breast carcinoma in the metastatic and adjuvant setting, ovarian carcinoma, tumors of young adults such as Ewing sarcoma and small cell lung carcinoma. In patients with refractory nonseminomatous testicular cancer there have been a number of studies performed with high-dose chemotherapy showing a 15% complete and prolonged remission. For other tumor types and settings it will be necessary to perform randomized studies before firm conclusions can be drawn. For example, this is especially important for patients with breast carcinoma with more than three positive axillary lymph nodes. Preliminary data from various groups compared to historical controls treated with standard adjuvant chemotherapy show favorable results of adjuvant chemotherapy containing high-dose chemotherapy. Many relatively small nonrandomized studies are performed in various stages of disease for ovarian carcinoma. Although there are long-term survivors reported it is currently difficult to draw firm conclusions. The potentially safer therapy of high-dose chemotherapy may reveal in the near future the role of high-dose chemotherapy in solid tumors.

The collection and evaluation of peripheral blood progenitor cells sufficient for repetitive cycles of high-dose chemotherapy support

BACKGROUND

The development of an optimized peripheral blood progenitor cell (PBPC) harvest protocol to provide support for repetitive chemotherapy cycles is described.

STUDY DESIGN AND METHODS

PBPCs mobilized by cyclophosphamide plus granulocyte-colony-stimulating factor (G-CSF) were studied in 163 leukapheresis harvests from 26 lymphoma patients. Harvested cells were transfused with two chemotherapy cycles and with an autologous bone marrow transplant. Progenitor cell content was examined in the context of hematopoietic engraftment.

RESULTS

Mobilization allowed the harvest of large numbers of PBPCs. Peak harvests tended to occur after the recovering white cell count exceeded 10 x 10(9) per L. CD34+ lymphomononuclear cell (MNC) and colony-forming units-granulocyte-macrophage (CFU-GM) counts correlated poorly, but both measures peaked within 24 hours of each other in 21 of 26 patients, which demonstrated PBPC mobilization. Engraftment of platelets (> 50 x 10(9)/L) and granulocytes (> 500 x 10(6)/L) was achieved in a median of 20.5 and 16 days, respectively. A minimum number of progenitors necessary to ensure engraftment could be derived.

CONCLUSION

Cyclophosphamide and G-CSF allowed the harvest of sufficient PBPCs to support multiple rounds of chemotherapy. Harvest should commence when the recovery white cell count exceeds 10 x 10(9) per L. PBPC harvest CD34+MNC counts are as useful as CFU-GM results in the assessment of PBPC content, and they may allow harvest protocols to be tailored to individual patients.

Expanding the role of blood progenitor cells

Five years ago the haemopoietic growth factors were introduced to clinical practice with the aim of reducing the depth and duration of chemotherapy induced neutropenia. Now, they have a wider remit, with important roles in supporting dose intensive treatments and mobilising BPC. Similarly, BPC themselves have until now been predominantly used in autologous transplantation following myeloablative treatments. In the next five years we can expect to see BPC from novel sources manipulated to feature in many new roles, including allogeneic transplantation, multicyclic dose-intensive chemotherapy and gene therapy.

Malignant mixed müllerian tumors of the ovary: experience with surgical cytoreduction and combination chemotherapy

BACKGROUND

The role of surgical cytoreduction and combination chemotherapy for malignant mixed müllerian tumors (MMMT) of the ovary was evaluated.

METHODS

A retrospective review of 27 women with ovarian MMMT treated from 1980 to 1990 was performed.

RESULTS

The International Federation of Gynecology and Obstetrics stages for the 27 women were 1 Stage I, 3 Stage II, 17 Stage III, and 6 Stage IV. Only 10 of the 23 patients with Stage III or IV disease were cytoreduced optimally. With respect to postoperative therapy, 3 women received no treatment, 6 were treated with whole abdomen radiotherapy, 1 received melphalan, and 17 received chemotherapy incorporating a platinum agent (3), doxorubicin (4), or both (10). The significant prognostic factors were stage (P < 0.001) and, for women with Stage III or IV disease, the feasibility of cytoreductive surgery (P = 0.03). The four patients in Stages I or II remained disease free after an interval of at least 5 years. The median and 5-year survival rates for patients with Stages III or IV disease was 18 months and 8%, respectively. Patients in Stage III or IV for whom optimal cytoreduction was not possible had a 2-year survival of 14%, whereas optimal cytoreduction was associated with a 52% 2-year survival. Median survival for the 14 women with Stage III or IV ovarian MMMT treated with combination chemotherapy was 25 months and nine women achieved progression free intervals of greater than 18 months.

CONCLUSIONS

Aggressive surgical cytoreduction followed by combination chemotherapy may result in improved progression free intervals for women with advanced ovarian MMMT. However, a major improvement in prognosis for this rare malignancy has not yet been achieved.

Multiple cycles of high dose chemotherapy supported by hematopoietic progenitor cells as treatment for patients with advanced malignancies

BACKGROUND

Retrospective studies suggest that dose intensity is an important determinant of outcome in the treatment of patients with a variety of malignant diseases such as breast cancer, ovarian cancer, and lymphoma. Unfortunately, these results have not been clearly substantiated in prospective randomized trials. One problem with these studies may be that the degree of dose escalation is not sufficient to result in an improved outcome because the chemotherapy doses are limited by hematopoietic toxicity. In an attempt to deliver more dose-intensive therapy, the feasibility of the administration of multiple cycles of high dose chemotherapy with hematopoietic progenitor cell and growth factor support was investigated in patients with advanced malignancies.

METHODS

Nineteen patients with metastatic breast cancer and six patients with refractory non-Hodgkin's lymphoma were initially treated with etoposide (VP-16) (2 gm/m2) and granulocyte-colony stimulating factor (G-CSF). Peripheral blood hematopoietic progenitor cells were collected by leukapheresis and cryopreserved as the patients' leukocyte counts recovered from the nadir induced by VP-16. Patients were then treated with four cycles of mitoxantrone (18 mg/m2), thiotepa (150-200 mg/m2) and cyclophosphamide (4500-5000 mg/m2) as a 48-72 hour continuous infusion followed by infusion of one-quarter of their progenitor cells 48 hours later. All patients also received G-CSF (5 micrograms/kg/day) until engraftment.

RESULTS

A total of 88 of a planned 100 cycles of therapy were administered to these 25 patients. The median time to recovery of an absolute neutrophil count of 500/microliters or greater was 13-14 days (range, 7-18 days) and time to recovery of a platelet count of 20,000/microliters or greater was 13-14 days (range, 7-16 days) after the initiation of each cycle of chemotherapy. The median number of platelet transfusions required after each cycle was 2-3 (range, 0-18 transfusions) and the number of erythrocyte transfusions was 4 (range, 0-10). The most common toxicity was diarrhea. Prophylactic intravenous antibiotics were administered to avoid fever with neutropenia. Two patients developed interstitial pneumonitis and one patient died. One heavily pretreated patient failed to engraft after the first cycle. Reversible veno-occlusive disease of the liver developed in one patient after the fourth cycle of therapy. Four patients progressed while on therapy. Eight patients were disease free and 13 patients had a partial response or had a positive bone scan as the only evidence of disease at the completion of therapy. Seven patients, two with lymphoma and five with breast cancer (28%), remain progression free with a median follow-up of 24.7 months (range, 17-28 months).

CONCLUSIONS

Support with hematopoietic progenitor cells and growth factors allows the timely administration of repetitive cycles of high dose chemotherapy, resulting in a significant increase in dose intensity with acceptable toxicity.

Dose-intensive therapy for small cell lung cancer

Enhancement of dose and dose intensity increases tumor response and may enhance long-term progression-free survival in patients with small cell lung cancer. Several strategies are identified to intensify therapy safely: a traditional induction/intensification mode, in which high-dose therapy with hematopoietic stem cell support is used to treat patients responding to conventional-dose therapy; and multicycle dose-intensive approaches, in which higher-dose therapy is administered over multiple cycles at initiation of therapy. This paper reviews some of the recently completed and activated trials (particularly those developed at the Dana-Farber Cancer Institute) exploring these concepts.

A comparison of peripheral blood stem cell apheresis using the Fenwal CS3000 Plus and COBE Spectra

We have compared the leukapheresis products collected on the Fenwal CS3000 Plus and COBE Spectra in a well-controlled patient population. While statistically significant differences were found, i.e. in product hematocrit, volume, number of granulocytes and platelets collected, these are not felt to be physiologically important. Similar efficiency in collecting mononuclear cells and colony forming unit assay results indicate that each instrument is capable of harvesting hematopoietic progenitor cells from peripheral blood.

High-dose chemotherapy with autologous peripheral stem cell support in advanced ovarian cancer

Twenty patients with advanced (stage III-IV), previously untreated ovarian carcinoma were treated by: (a) induction chemotherapy (40 mg/m2 cisplatin, days 1-4; 1.5 g/m2 cyclophosphamide, day 4; every 4 weeks for two cycles) followed by (b) intensification chemotherapy (100 mg/m2 cisplatin, day 1; 650 mg/m2 etoposide, day 2; 1.8 g/m2 carboplatin, day 3). Eligibility criteria further included: age less than 55 years, moderately good to poor tumour grade, macroscopic (> 0.5 cm) residual tumour. Autologous peripheral stem cells were recruited after the induction cycles and, to ensure haematological support, autologous bone marrow harvesting was routinely performed in the first 14 cases. Haematological support consisted of autologous peripheral stem cells and autologous bone marrow transplant in 16 and four patients, respectively. All patients are evaluable for toxicity and 19 for pathological response, one being dead of systemic mycosis 35 days after the autologous bone marrow transplant. Severe extra-haematological toxicities were the following: gastrointestinal (100%), neurological (10%), hepatic (10%). Pathological response was detected in 84% of cases (CR 37%, microscopic PR 26%, macroscopic PR 21%). Median follow-up times of 48 and 41 months have been reached respectively from enrolment and second-look. Four-year 62% overall and 57% progression-free survivals have been reached. Ten patients are still alive with NED (six of seven with CR, three of five with microscopic PR, and one of four with macroscopic PR). Autologous peripheral stem cell transplant significantly reduced the duration of aplasia compared with autologous bone marrow transplant, and toxicity was proved to be manageable in those patients undergoing autologous peripheral stem cell transplant. The prolonged disease-free survival in patients showing CR and microscopic PR suggests that further investigation on this new approach is worthwhile.

Potential strategies for improving the results of high-dose chemotherapy in patients with metastatic breast cancer

High-dose chemotherapy (HDC) is the most effective approach for inducing complete remissions in patients with metastatic breast cancer, and although most patients will relapse, a small percentage (10%-15%) achieve durable remissions beyond five years. Additionally, HDC has produced five-year relapse-free survival rates in excess of 70% in patients with stage II breast cancer with > 10 nodes. The use of HDC in breast cancer remains controversial and randomised trials are required to assess the survival impact of this approach. The introduction of haematopoietic growth factors (HGF) and peripheral blood progenitor cells (PBPC) has advanced the use of HDC by reducing treatment-related mortality (from 20% to 5%) and by allowing the development of multiple cycles of intensive therapy. Based on tumour kinetic models we have hypothesised that multiple, rapidly cycled courses of high-dose therapy may improve the rate of durable remission in metastatic breast cancer. The feasibility of this approach has been shown in a series of pilot studies in which one or more courses of high-dose cyclophosphamide and recombinant granulocyte colony-stimulating factor (G-CSF) (filgrastim) were given to obtain PBPC which were then used to support one or more courses of HDC. In successive studies the HDC component consisted of: a single course of carboplatin, etoposide and cyclophosphamide; four courses of carboplatin; tandem courses of thiotepa; or a sequence of melphalan and thiotepa. Promising response rates have been produced in advanced breast and ovarian cancer with the later generation of regiments. These results justify the conduct of prospective randomised trials.

The evidence for increasing cytotoxic dose intensity in the treatment of advanced ovarian cancer

There is a body of conflicting evidence regarding the place of dose intense chemotherapy for advanced ovarian cancer. It remains unproven whether dose intensity is more important than total dose delivered, and measures of drug delivery to the tumour itself are absent or crude. There are various methods under evaluation for reducing the toxicity of chemotherapeutic drugs, thus enabling larger doses to be given. However, we must not lose sight of the fact that current treatment is palliative for the majority of women, making the quality of life an important issue. The place of dose intense cytotoxic chemotherapy, for the treatment of advanced ovarian cancer, must be evaluated in large, carefully designed, prospective trials which, if possible, should include a quality of life assessment.

Peripheral blood progenitor cells versus bone marrow

Transplantation of mobilized peripheral blood progenitor cells has generally produced shortening of the period of posttransplant aplasia that is characteristic of bone marrow grafts. However, there has been no large prospective randomized study to compare these two sources of hematopoietic cells or to determine their relative merits. This issue is explored in this review.

Efficacy of peripheral blood stem cell transplantation

With the advancement in apheresis technique and collection, the role of peripheral blood stem cell (PBSC) transplantation has emerged. PBSC are now being utilized either alone to reconstitute hematopoiesis following high-dose myeloablative therapy, or in combination with autologous bone marrow transplantation to enhance hematopoietic recovery, or as supportive therapy to allow dose-intensity of conventional chemotherapy. The role and efficacy of PBSC transplantation will be reviewed in the article.