High-dose combination alkylating agents with bone marrow support as initial treatment for metastatic breast cancer

Should we continue to study high-dose chemotherapy in metastatic breast cancer patients? A critical review of the published data

Data from eight randomised trials on high-dose chemotherapy (HDC) for metastatic breast cancer (MBC) have been published, but only seven studies are evaluable after the Bezwoda trial was discredited. Moreover, overall survival (OS) has been evaluated in only four out of seven studies since three had a crossover design. OS was similar for the HDC and standard-dose chemotherapy (SDC) group in the four evaluable trials, while disease-free survival (DFS) was improved in the HDC group in six of the seven trials. The delay in relapse for patients with metastatic disease represents an important clinical outcome; furthermore, since none of the reported studies randomised more than 220 patients, their statistical power may have been too limited to detect meaningful survival differences. Finally, preliminary experiences have shown that HDC seems to be the ideal platform upon which to build novel therapies. In conclusion, HDC remains an important field of clinical research for breast cancer patients with stage IV disease and, from the studies reported in this article, there is some evidence for offering this therapeutic modality to selected patients who are interested in a medically aggressive approach.

Economic analysis of conventional-dose chemotherapy compared with high-dose chemotherapy plus autologous hematopoietic stem-cell transplantation for metastatic breast cancer

We performed an economic analysis of data from 180 women in a clinical trial of conventional-dose chemotherapy vs high-dose chemotherapy plus stem-cell transplantation for metastatic breast cancer responding to first-line chemotherapy. Data on resource use, including hospitalizations, medical procedures, medications, and diagnostic tests, were abstracted from subjects' clinical trial records. Resources were valued using the Medicare Fee Schedule for inpatient costs at one academic medical center and average wholesale prices for medications. Monthly costs were calculated and stratified by treatment group and clinical phase. Mean follow-up was 690 days in the transplantation group and 758 days in the conventional-dose chemotherapy group. Subjects in the transplantation group were hospitalized for more days (28.6 vs 17.8, P=0.0041) and incurred higher costs (US dollars 84055 vs US dollars 28169) than subjects receiving conventional-dose chemotherapy, with a mean difference of US dollars 55886 (95% CI, US dollars 47298-US dollars 63666). Sensitivity analyses resulted in cost differences between the treatment groups from US dollars 36528 to US dollars 75531. High-dose chemotherapy plus stem-cell transplantation resulted in substantial additional morbidity and costs at no improvement in survival. Neither the survival results nor the economic findings support the use of this procedure outside of the clinical trial setting.

High dose chemotherapy and autologous bone marrow or stem cell transplantation versus conventional chemotherapy for women with early poor prognosis breast cancer

BACKGROUND

Overall survival rates are disappointing for women with early poor prognosis breast cancer. There is a hypothesis that high dose chemotherapy with autologous bone marrow or stem cell transplant (autograft) may improve survival rates by permitting higher doses of adjuvant chemotherapy to be given.

OBJECTIVES

To compare the effectiveness of high dose chemotherapy and autograft versus conventional chemotherapy for women with early poor prognosis breast cancer.

SEARCH STRATEGY

We searched the Cochrane Breast Cancer Group specialised register, The Cochrane Controlled Trials Register (Cochrane Library Issue 3, 2002), MEDLINE (1966 to Aug. 2002), EMBASE (1980 to Aug. 2002), PsycINFO (1984 to Aug. 2002), Cinahl (1982 to July 2002), the websites of co-operative research groups and ASCO (American Society of Clinical Oncologists) and reference lists of articles found.

SELECTION CRITERIA

Randomised controlled trials comparing the effectiveness of high dose chemotherapy and autograft versus conventional chemotherapy for women with early poor prognosis breast cancer.

DATA COLLECTION AND ANALYSIS

We identified nine trials that met the inclusion criteria. Three independent reviewers extracted data.

MAIN RESULTS

In total 1758 women were randomised to receive high dose chemotherapy with autograft and 1767 women were randomised to receive conventional chemotherapy. There were 48 non cancer-related deaths on the high dose arm and four on the conventional dose arm (RR 7.74, 95% CI (3.43, 17.50). Since many studies have not completed follow-up, overall survival rates were in most cases based on results to date. There was no statistically significant difference in overall survival between women who received high dose chemotherapy with autograft and women who received conventional chemotherapy, either at three years (RR 1.02, 95% CI (0.98, 1.06)), or at five years (RR 0.98, 95% CI (0.93, 1.05)). There was a statistically significant benefit in event-free survival at three years for the group who received high dose chemotherapy (RR 1.11, 95% CI (1.05, 1.18)). However at five years there was no statistically significant difference between the groups (RR 1.00, 95% CI (0.92, 1.08)). Side-effects were more common and more severe in the high dose group though most were reversible. Women in the high dose group reported significantly worse quality of life scores immediately after treatment but at one year there was no statistically significant difference between the groups in quality of life scores.

REVIEWER'S CONCLUSIONS

There is insufficient evidence to support the routine use of high dose chemotherapy with autograft for women with early poor prognosis breast cancer.

High dose chemotherapy and autologous bone marrow or stem cell transplantation versus conventional chemotherapy for women with metastatic breast cancer

BACKGROUND

There is a hypothesis that high dose chemotherapy with autologous bone marrow or stem cell transplantation (autograft) may improve survival for women with metastatic breast cancer.

OBJECTIVES

To compare the effectiveness of high dose chemotherapy and autologous bone marrow or stem cell transplantation with conventional chemotherapy for women with metastatic breast cancer.

SEARCH STRATEGY

We used the Cochrane Breast Cancer Group search strategy, adding these terms: bone marrow transplantation, stem cell transplantation, autologous stem cell support. The following databases were searched: MEDLINE (until August 2002), EMBASE (until July 2002), ASCO (American Society of Clinical Oncology) (1995-2002) and the COCHRANE LIBRARY (Issue 3 2002). We searched the Cochrane Breast Cancer Group database and cooperative research groups' websites for unpublished trials.

SELECTION CRITERIA

Randomised controlled trials comparing the effectiveness of high dose chemotherapy and autograft with conventional chemotherapy for women with metastatic breast cancer. Studies included one or more of the following outcomes: treatment related mortality, overall or progression-free survival at 1, 2, 3, 5 or 7 years, morbidity, quality of life measures, time to tumour progression, overall survival time.

DATA COLLECTION AND ANALYSIS

Five randomised controlled trials met the inclusion criteria. Two independent reviewers extracted data.

MAIN RESULTS

In total 382 women were randomised to receive high dose chemotherapy with autograft and 358 were randomised to receive conventional treatment. There were ten treatment related deaths among the high dose group and none reported in the control (conventional dose) group (RR 5.70, 95%CI (1.30, 25)). There was no statistically significant difference in overall survival between the high dose and control groups (at one year: RR 0.99, 95% CI (0.91, 1.08); three years: RR 1.16 95% CI (0.90, 1.51); five years: RR 1.28, 95% CI (0.72, 2.27)). At one and two years of follow up, a statistically significant difference in progression free survival was reported, favouring the high dose group (one year: RR 1.81, 95% CI (1.39,2.34); two years: RR 1.96, 95% CI (1.32, 2.90 ). However this difference was not evident at three or five years (three years: RR 1.44, 95% CI (0.85, 2.44); five years: RR 1.21, 95% CI (0.40, 3.69). Toxicity was more severe in the high dose group. None of the trials has completed follow up and further data are awaited.

REVIEWER'S CONCLUSIONS

Although there is evidence that high dose chemotherapy and autograft improves progression free survival at one and two years' follow up compared to conventional chemotherapy, there is no evidence of benefit in overall survival.

High-dose chemotherapy and stem cell support for breast cancer: where are we now?

To date, there is no definitive evidence that high-dose chemotherapy and haematopoietic stem cell support offers a survival advantage over conventional-dose chemotherapy for metastatic or high-risk primary breast cancer. Studies of metastatic disease discussed in this review have an adequate duration of follow-up given the short natural history of metastatic breast cancer. Thus, the results of these studies are unlikely to change with a longer observation period. On the other hand, studies of high-dose chemotherapy in the treatment of high-risk primary breast cancer need longer follow-up in light of the longer natural history of this type of disease. Results of unpublished studies and longer follow-up of available studies may still demonstrate a survival advantage for high-dose chemotherapy in patients with metastatic or high-risk primary breast cancer. We continue to encourage participation in innovative clinical studies.

Methodologic guidelines for the design of high-dose chemotherapy regimens

PURPOSE

The objective of this report is to review the research methods that have been used in the design, analysis, and reporting of Phase I dose-escalation studies of high-dose chemotherapy (HDCT) with bone marrow or stem cell support and to propose new guidelines for such studies that incorporate emerging principles of pharmacology, toxicity assessment, statistical design, and long-term follow-up.

METHODS

We performed a search of original, English-language, peer-reviewed full-length reports of HDCT (with or without radiotherapy) and unmanipulated hematopoietic precursor support (autologous bone marrow or stem cells or allogeneic bone marrow) in which one or more drug doses were escalated to identify dose-limiting toxicities needed for the design of subsequent Phase II trials. We reviewed the design, execution, analysis, and reporting of these trials to develop a coherent set of guidelines for the initiation of new HDCT regimens. The primary elements included in our analysis were the technique of dose escalation, the choice and application of toxicity grading scale, and the pharmacologic correlates of dose escalation. We also evaluated the methods employed to define dose-limiting toxicities and to select the maximum tolerated dose and the dose recommended for further study. We then examined whether subsequent Phase II trials based on these definitions corroborated the findings from the prior Phase I studies and summarized the findings from pharmacologic analyses that were reported from a subset of these investigations.

RESULTS

Thirty-five reports met the criteria for our literature review. Two standard methods of dose escalation (fixed increments or modified Fibonacci increments) were described in detail and were employed in the majority (30/35) of the studies. In 5 studies, the details of dose escalation were either not provided or not adequately referenced. There was marked heterogeneity among toxicity grading methods; scales used included the National Cancer Institute Common Toxicity Criteria (or similar scales such as the United States cooperative group or World Health Organization scales) as well as substantially modified versions of those instruments. Wide variations in the methods used to identify dose-limiting toxicities were observed. Statistical considerations, applied to the identification of the maximum tolerated or Phase II recommended dose, were similarly heterogeneous. Phase II trial designs varied from a simple expansion of the Phase I trial to separate, formally conducted studies. Nine Phase I trials featured pharmacologic analyses, and these ranged from simple pharmacokinetic evaluations to more complex analyses of the relationship between drug dose and the molecular targets of drug action.

CONCLUSIONS

Phase I clinical trials in the HDCT setting have been designed, analyzed, and reported using heterogeneous methods that limited their application to Phase II and II investigations. Moreover, correlative pharmacologic analyses have not been routinely undertaken during this critical Phase I stage. We propose guidelines for the design of new Phase I studies of HDCT based on 4 essential elements: (1) rational preclinical and clinical pharmacologic foundation for the regimen and for the agent selected for dose escalation; (2) incorporation of analytical pharmacology in the design and analysis of the regimen under investigation; (3) clear, prospective definitions of the dose- or exposure-limiting toxicities that can be distinguished from modality-dependent toxicities; selection of an appropriate toxicity grading scale, including an assessment of cumulative, delayed, and long-term effects of HDCT, particularly when designing tandem or repetitive cycle regimens; and (4) statistical input into the design, execution, analysis, interpretation, and reporting of these studies.

Use of capecitabine as first-line therapy in patients with metastatic breast cancer relapsing after high-dose chemotherapy and autologous stem cell support

High-dose chemotherapy with autologous stem cell support (HDC-ASCS) can produce high complete remission rates in patients with metastatic breast cancer (MBC). However, the majority of those so treated will relapse within 3 years. The ability of such patients to tolerate further myelosuppressive chemotherapy may be limited and the best therapy is undefined. In this retrospective study we assessed the role of capecitabine as initial therapy after relapse. Ten patients (median age = 47 years; oestrogen receptor-positive, n = 4; visceral disease, n = 6; prior anthracycline, n = 8, prior taxanes, n = 10), whose disease progressed at a median of 246 days (range 69-480) after HDC-ASCS and who were treated with capecitabine (2500 mg/m2 per day for 2 weeks of a 3-week cycle) as initial therapy for relapse, were assessed retrospectively for response and toxicity. They received a median of eight cycles (range 4-24) of capecitabine. The toxicities encountered while receiving capecitabine were: hand-foot syndrome (grade 1, n = 3; grade 2, n = 4; grade 3, n = 1); diarrhoea (grade 1, n = 1; grade 2, n = 3); nausea (n = 2) and fatigue (n = 5). Haematological toxicity was seen in only one patient. No patient required hospitalization for toxicity. Three achieved a complete remission, four a partial remission and three disease stabilization. After a median follow-up of 183 days from commencing capecitabine (range 97-540), all patients were alive and five were in remission. Five progressed after remissions that lasted between 63 and 252 days. Oral capecitabine is an active and well-tolerated agent when used alone as first-line therapy in patients who have relapsed after HDC-ASCS for MBC.

Stem cell dose and tumorbiologic parameters as prognostic markers for patients with metastatic breast cancer undergoing high-dose chemotherapy with autologous blood stem cell support

We report on the prognostic significance of tumorbiologic parameters and CD34(+) cell dose in 120 patients with metastatic breast cancer (MBC) who received high-dose chemotherapy (HDCT) with autologous blood stem cell transplantation as first-line treatment. Her2/neu, p53, Ki67, and bcl-2 protein expression were studied using immunohistochemical staining on formalin-fixed, paraffin-embedded primary tumor sections. DNA content of tumor cells (DNA-index) and tumor cell proliferation (S-phase fraction) were measured by DNA flow cytometry. The relationship between these parameters and the CD34(+) cell dose and progression free (PFS) and overall survival (OS) was analyzed. With a median follow-up period of 40 months (range, 7-89 months), no more than two metastatic sites (relative risk [RR] = 3.84 [95% confidence interval (CI) 1.49-10]; p =.005) and hyperploidy (RR = 2.58 [95% CI 1.26-5.26]; p =.009) were independent predictors of longer PFS according to multivariate analysis. Independent prognostic factors of longer OS included one or two metastatic sites (RR = 4.16 [95% CI 1.96-4.16]; p <.001), a positive combined hormone receptor status (RR = 2.45 [95% CI 1.45-4.14]; p =.001) and a high number of infused stem cells (>7.8 x 10(6) CD34(+) cells per kg body weight) (RR = 2.0 [95% CI 1.17-3.42]; p =.01). In conclusion, positive hormone receptors, < or =2 metastatic sites, high DNA-index and high CD34(+) cell dose (>7.8 x 10(6) CD34(+) cells per kg) are predictors for a favorable outcome after autotransplantation for MBC. Our observation might indicate a favorable effect of HDCT in MBC patients with overexpression of Her2/neu who might have a worse prognosis when treated with conventional chemotherapy.

A Phase II study of paclitaxel by 24-hour infusion and ifosfamide in anthracycline-resistant metastatic breast carcinoma

BACKGROUND

A Phase II study was performed to investigate the efficacy and tolerability of paclitaxel and ifosfamide chemotherapy for the treatment of anthracycline-resistant metastatic breast carcinoma (MBC).

METHODS

Recurrent or progressed MBC within 12 months after anthracycline-based chemotherapy was defined as anthracycline-resistant. A 24-hour infusion of paclitaxel (175 mg/m(2)) on Day 1 and subsequent infusions of ifosfamide (1.8 g/m(2)/day) with mesna (360 mg/m(2)/day) on Days 2- 4, were performed every 3 weeks. Twenty-one patients were eligible for toxicity analysis. Response rate and survival duration were evaluated in 21 patients. Frontline chemotherapy was the FAC (5-fluorouracil, doxorubicin, cyclophosphamide) regimen in all patients.

RESULTS

Objective response was found in 9 patients (42.9%), including complete response in 3 (13.4%). Median response duration and median survival duration were 10 months (range, 2-24+) and 19+ months (range, 2-32+), respectively. Sixteen (76%) experienced Grade 3/4 leukopenia controllable with granulocyte macrophage colony-stimulating factor. Other significant toxicities were peripheral neuropathy (n = 3), mucositis (n = 2), and liver dysfunction (n = 1). However, there was no chemotherapy-related death.

CONCLUSIONS

Paclitaxel by 24-hour infusion combined with ifosfamide is efficacious in the treatment of anthracycline-resistant MBC with tolerable toxicity. Further trials verifying the result of the authors' study are warranted.

High-dose chemotherapy in advanced breast cancer

Based on in vitro and animals studies which assess dose effect relationship specially for alkylating agent, and on the importance on dose intensity in human protocols, high-dose chemotherapy with stem cell support has been widely evaluated in various tumours, particularly in breast cancer. Moreover, in the last few years, the utilization of hematopoietic growth factors and peripheral stem cells has permitted a large diffusion of this approach. However, there is not yet clear data on the place of such a treatment in breast cancer. Few randomized trials are available, with mature data. Only one shows an advantage for high-dose therapy in metastatic disease. In adjuvant setting, sample sizes are too small or follow-up not long enough to draw any definitive conclusion on the place of high-dose consolidation chemotherapy in breast cancer. In inflammatory breast cancer, which is a much more less frequent disease, encouraging results have been published in phase two studies, looking at pathological response, or in pilot studies. The next few years will give a mature date of randomized trials which evaluate high-dose chemotherapy given after conventional treatment in metastatic or high risk disease. Effort should be done to better evaluate this strategy in terms of cost and quality of life and to design new studies aimed to evaluate front line multiple intensification.

High-dose chemotherapy and CD34-selected peripheral blood progenitor cell transplantation for patients with breast cancer metastatic to bone and/or bone marrow

Fifty women with breast cancer metastatic to bone or bone marrow involvement on light microscopy at the time of initial evaluation were treated with high-dose chemotherapy (HDC) and peripheral blood progenitor cell (PBPC) transplantation with CD34(+) cell selection using the Isolex 300i system. All patients received induction chemotherapy. PBPC were mobilized with chemotherapy and granulocyte colony-stimulating factor. The median CD34(+) progenitor purity was 94.7% (range 72-98.7%) and recovery 38.4% (range 21-60%). Forty-eight hours after HDC with cyclophosphamide, cisplatin and carmustine, PBPC were reinfused. Median time to neutrophil count >0.5 x 10(9)/l was 9 (range 9-12) days and to platelet transfusion independence 11 (4-30) days. These data demonstrate that selected CD34(+) PBPCs allow rapid hematologic reconstitution after HDC. During follow-up, 23% of patients developed herpes zoster. Two patients developed cytomegalovirus infections. Three patients developed fungal infections. The development of these infections was not associated with steroid use but appeared more frequently in patients with diabetes mellitus. Seventy-four per cent of patients received steroids for pulmonary toxicity. Treatment-related mortality was 4%. Progression-free survival and overall survival at 35 months was 22.4% and 40.5%, with a median of 11.4 months and 15.4 months, respectively.

Maspin and mammaglobin genes are specific markers for RT-PCR detection of minimal residual disease in patients with breast cancer

BACKGROUND

This study evaluates the specificity of some reverse-transcriptase polymerase chain reaction (RT-PCR) assays for the detection of residual tumor cells in breast cancer patients. The following markers have been analysed: carcinoembryonic antigen (CEA), cytokeratins (CK19 and CK20), polymorphic epithelial mucin (MUC-1), epidermal growth factor receptor (EGFR), maspin, and mammaglobin. RT-PCR was employed to detect breast cancer cells in peripheral blood (PB), bone marrow (BM), and stem cell leukoaphereses (PBPC).

PATIENTS AND METHODS

We evaluated the specificity of our RT-PCR assays on a panel of breast cancer specimens (n = 30), on PBPC in patients undergoing high-dose chemotherapy (n = 38), on BM (n = 7) and PB (n = 5) samples obtained from patients with breast cancer. Marrow cells, PB, and PBPC from normal subjects or hematological tumor patients were tested as negative controls.

RESULTS

Only maspin and mammaglobin met the criteria of sensitivity and specificity required for the detection of residual disease; they were expressed in 80% and 97% of breast cancer specimens, respectively, and not expressed in normal controls. CK19, CK20. EGFR, MUC-1, and CEA were sometimes expressed in normal blood cells and/or hematological tumors.

CONCLUSIONS

Our data support the notion that maspin and mammaglobin are useful markers for RT-PCR detection of minimal residual disease (MRD) in breast cancer patients, and that perspective clinical studies are needed to determine wether RT-PCR assays will be useful in assessing prognosis, tailoring therapy, or developing new strategies for ex vivo purging.

An on-site audit of the South African trial of high-dose chemotherapy for metastatic breast cancer and associated publications

PURPOSE

The randomized study reported by Bezwoda et al of high-dose chemotherapy (HDC) for treatment of metastatic breast cancer was audited on site to verify the study results. Additional published studies were reviewed to determine whether they had been subject to the required institutional oversight.

PATIENTS AND METHODS

Ninety patients were reported to have been randomized and treated on this trial. A log of the names, hospital numbers, entry dates, and regimen received had been provided by the principal investigator. A search of more than 15,000 sets of medical records available from two Johannesburg hospitals was performed to locate records for as many of these 90 patients as possible. Standard auditing techniques were used. Additional clinical trials published by Bezwoda were compared against the minutes of the University of the Witwatersrand Committee for Research on Human Subjects to verify review and approval.

RESULTS

Records for only 61 of the 90 patients could be found. Of these 61, only 27 had sufficient records to verify eligibility for the trial by the published criteria. Of these 27, 18 did not meet one or more eligibility criteria. Only 25 patients appeared to have received their assigned therapy temporally associated with their enrollment date, and all but three of these 25 received HDC. The treatment details of individual patients were at great variance from the published data. Nine other trials reported by Bezwoda were not reviewed or approved by the appropriate institutional committee despite statements to the contrary in the publications.

CONCLUSION

The multiple publications of this study do not report verifiable data, and nine other publications coauthored by the principal investigator contain at least one major untrue statement.

High-Dose Chemotherapy with Autologous Stem Cell Rescue as a Treatment Modality for Breast Cancer

Retrospective analyses of clinical trials as well as several prospective randomized clinical trials designed to evaluate dose intensity have emphasized the importance of intensive chemotherapy in determining outcomes in breast cancer treatment. One strategy that can deliver a large increment in dose intensity is high-dose chemotherapy with autologous stem cell transplantation (HDC-ASCT), since it overcomes myelosuppression, a major dose-limiting toxicity of most chemotherapy regimens. Phase II data from HDC-ASCT trials have indicated improved complete remission rates and longer remission duration when compared to historical conventional-dose chemotherapy regimens. With declining treatment-related mortality (TRM) through improvements in supportive care and innovations in stem cell collection procedures, exploration of HDC-ASCT in prospective randomized trials has been made possible. Several prospective randomized trials have completed accrual and early results are now available, while other studies are still ongoing. Unfortunately the trial designs are quite varied, the characteristics of patients differ from study to study, the early data provide conflicting results, and the follow-up is quite short, making firm conclusions impossible at present. Of note, the comparison arms in several of the studies are performing better than historical nontransplant treatments, perhaps a result of an intermediate dose intensity employed in the nontransplant arm of these trials. These data suggest that dose intensity, whether supported by stem cells or hematopoietic growth factors, may be quite important in optimizing treatment outcomes, affirming earlier concepts of the importance of dose intensity. Further follow-up of the current clinical trials and analyses of ongoing studies not yet reported are necessary before firm conclusions are possible as to the optimal strategy of using dose intensity in the management of breast cancer.

Randomized trials of high dose chemotherapy for breast cancer

'Now is not the end. It is not even the beginning of the end. But it is, perhaps, the end of the beginning'Winston Churchill in a speech to the Canadian Senate and House of Commons, December 30, 1941. In laboratory models of cancer, dose of cytotoxic chemotherapy correlates with curative therapy, while cumulative dose is associated with longer survival for those who are not cured. These observations suggests a strategy of using high doses when cure is the objective but smaller doses over a prolonged period when palliation and survival are the goal. A strategy combining repetitive cycles of higher doses of cytotoxic therapy, followed by the optimal combination of hormonal and biological agents based on the tumor's receptors might contribute to both the highest possible cure rate and the longest survival. The development of bone marrow transplant (BMT) for leukemias, and its subsequent modification for support after high dose therapy for other malignancies, has a long, complex and emotional history in medicine. At least partly because of firmly held opinions and the way large randomized trials are funded in the United States, few American randomized trials of BMT or high dose therapy strategies have been completed. The vast majority of published randomized BMT and high dose studies are European. Interestingly, in contrast, two large American randomized trials of high dose chemotherapy for breast cancer had actually completed accrual. Accrual on a third was on target until the presentation of five very small or very early randomized trials at the American Society of Clinical Oncology meeting in May of 1999. Results from some of these trials, which were analyzed after a relatively brief follow-up, are too premature to allow definitive conclusions. Nevertheless, these data have been over and misinterpreted within the scientific and lay communities. The remaining studies included a limited number of patients, thus restricting the statistical power of the observations. The desire for quick answers impeded dispassionate analysis of the available data. The opportunity for collegial review of the data further deteriorated with another round of press coverage when the data from the South African adjuvant study were found to be unreliable. Rather than increasing commitment to accrual on randomized and appropriate pilot trials, accrual to the only large American study in existence at that time trickled to a halt. In response to press coverage, Susan Edmonds from the Fred Hutchinson Cancer Research Center observed that 'the NYT article tends to cast shadows generally on the therapy and those providing the therapy rather than pointing out early in the article (where the public will readily see it) that there are a number of very credible research institutions conducting research directed at breast cancer, some looking at high dose chemotherapy and stem cell transplantation.' Dr. Rodenhuis, presenting the large positive Dutch Randomized study (funded by the Dutch insurance industry) at ASCO in 2000, commented on the 'unreasonably high expectations until 1999' and 'unreasonably negative [opinion-ed] since 1999' for high dose adjuvant chemotherapy for breast cancer.

The status of high-dose chemotherapy in breast cancer

High-dose chemotherapy in breast cancer is a subject of considerable controversy. Preliminary results from several randomized trials have shown that it is certainly not the breakthrough hoped for in the early 1990s. The available data are, however, compatible with a modest but potentially important effect on relapse-free survival in the adjuvant treatment of high-risk breast cancer. To prove such an effect, several more years of maturation are required for a number of randomized studies. At this point in time, there is no justification for the use of high-dose chemotherapy in breast cancer outside clinical studies.

Recombinant human thrombopoietin clinical development

Patients undergoing anticancer therapy are often at risk for developing severe and/or prolonged posttreatment thrombocytopenia. This can be associated with significant bleeding; currently, it is treated with supportive platelet transfusions. Frequent platelet transfusions can cause alloimmunization which requires HLA-matched donors and more frequent blood transfusions, and transmission of both viral and bacterial infections via platelet transfusions remains a concern. Furthermore, thrombocytopenia can mandate a decrease in the dose intensity of cytotoxic therapy by causing either delays or dose reductions in therapy administration. An intervention that reduces the risk or shortens the duration of severe thrombocytopenia would represent an important medical advance. Thrombopoietin (TPO), a naturally occurring, glycosylated polypeptide that was cloned by Genentech in 1994, is capable of inducing differentiation of stem cells into megakaryocytes and accelerating the maturation of megakaryocytes, thereby increasing the platelet count. Recombinant human TPO (rHuTPO) is currently undergoing testing in phase 1 and 2 studies in patients receiving myelosuppressive or myeloablative therapy. For the purposes of illustration, preliminary safety and activity data from one ongoing phase 1 myelosuppression trial (rHuTPO in women with advanced gynecologic malignancies receiving carboplatin) and one ongoing phase 1 myeloablation trial (rHuTPO for peripheral blood progenitor cell mobilization prior to myeloablative chemotherapy for high risk breast cancer) will be presented.

Pilot trial of interleukin-2 with granulocyte colony-stimulating factor for the mobilization of progenitor cells in advanced breast cancer patients undergoing high-dose chemotherapy: expansion of immune effectors within the stem-cell graft and post-stem-cell infusion

PURPOSE

To evaluate whether administration of interleukin-2 (IL-2) with granulocyte colony-stimulating factor (G-CSF) improves mobilization of immune effector cells into the stem-cell graft of patients undergoing high-dose chemotherapy and autografting.

PATIENTS AND METHODS

We performed a trial of stem-cell mobilization with IL-2 and G-CSF in advanced breast cancer patients receiving high-dose chemotherapy with cyclophosphamide, thiotepa, and carboplatin and stem cells followed by IL-2. The trial defined immune, hematologic, and clinical effects of IL-2 in this setting.

RESULTS

Of 32 patients enrolled, nine received G-CSF alone for mobilization. Twenty-one of 23 patients mobilized with IL-2 plus G-CSF had stem cells collected with more mononuclear cells than those receiving G-CSF (19.3 v 10.4 x 10(8)/kg; P =.006), but fewer CD34(+) progenitor cells (6.9 v 22.0 x 10(6)/kg; P =.049). The IL-2 plus G-CSF-mobilized patients had greater numbers of activated T (CD3(+)/CD25(+)) cells (P =.009), natural killer (NK; CD56(+)) cells (P =.007), and activated NK (CD56 bright(+)) cells (P: =.039) than those patients mobilized with G-CSF. NK (P =.042) and lymphokine-activated killer (LAK) (P =.016) activity was increased in those mobilized with IL-2 + G-CSF, whereas G-CSF-mobilized patients had a decline in cytolytic activity. In the third week posttransplantation, immune reconstitution was superior in those mobilized with IL-2 plus G-CSF based on greater numbers of activated T cells (P =.003), activated NK cells (P =.04), and greater LAK activity (P =.003). The 16 of 21 IL-2 + G-CSF-mobilized patients with adequate numbers of stem cells (> 1.5 x 10(6) CD34(+) cells/kg) collected engrafted rapidly posttransplantation.

CONCLUSION

The results demonstrate that G-CSF + IL-2 can enhance the number and function of antitumor effector cells in a mobilized autograft without impairing the hematologic engraftment, provided that CD34 cell counts are more than 1.5 x 10(6) cells/kg. Mobilization of CD34(+) stem cells does seem to be adversely affected. In those mobilized with IL-2 and G-CSF, post-stem-cell immune reconstitution of antitumor immune effector cells was enhanced.

A critique of the eleven randomised trials of high-dose chemotherapy for breast cancer

Data from 11 randomised studies on high-dose chemotherapy for breast cancer are currently available. Most investigators, patients and insurers would agree that the two discredited South African trials are uninterpretable, and that the Scandinavian trial (which compares one very high-dose cycle versus six escalated dose cycles) does not ask the question of high-dose therapy versus conventional-dose therapy. Only two of the eight remaining studies randomised more than 200 patients (783 patients for the Cancer and Leukaemia Group B (CALGB) and 885 for the Dutch study). Both of these studies have trends in relapse-free survival favouring high-dose therapy. In a planned analysis of the first 284 patients entered into the Dutch study, with a median follow-up approximately 7 years, both disease-free and overall survival were significantly improved in the high-dose therapy arm. These and the other trials are discussed in detail below.

Whither high-dose chemotherapy in breast cancer?

Four trials of high-dose chemotherapy with stem cell support in breast cancer in the adjuvant and metastatic settings have shown no long-term disease-free or overall survival gain. This relative failure of a single high-dose therapy we believe opens up the development of a dose-dense approach with block scheduling as the most promising way forward. This intensive chemotherapy can be more easily combined with the newer biological therapies and our prediction is that this will prove to be the most effective treatment in the future for women with poor risk breast cancer.

Ototoxicity after high-dose chemotherapy with cyclophosphamide, thiotepa and carboplatin followed by stem cell transplantation in patients with breast cancer

Our purpose was to determine the risk of ototoxicity in breast cancer patients receiving a myeloablative regimen consisting of cyclophosphamide 6000 mg/m2, thiotepa 500 mg/m2 and carboplatin 800 mg/m2 (CTCb) followed by stem cell transplantation. Fourteen consecutive patients with breast cancer were treated with high dose chemotherapy consisting of the CTCb regimen followed by stem cell transplantation. A pretransplant complete hearing study was obtained which consisted of hearing case history, audiometry and tympanometry. In addition, DPOAE (Distortion Product Otoaccoustic Emissions) was done to evaluate measurable changes in the cochlear (outer hair cell) functioning. Pre-transplant, all patients had no clinical evidence of hearing impairment and hearing studies were normal. Eleven patients had hearing studies and a telephone interview posttransplant. One patient was lost to follow-up and two patients died. One of the 11 patients tested had an abnormal post-transplant hearing study but none of them had clinically detectable hearing impairment. In our prospective study of breast cancer patients treated with the CTCb regimen, we did not observe clinically detectable hearing impairment in any of the patients tested.

Tailored fluorouracil, epirubicin, and cyclophosphamide compared with marrow-supported high-dose chemotherapy as adjuvant treatment for high-risk breast cancer: a randomised trial. Scandinavian Breast Group 9401 study

BACKGROUND

Chemotherapy drug distribution varies greatly among individual patients. Therefore, we developed an individualised fluorouracil, epirubicin, cyclophosphamide (FEC) regimen to improve outcomes in patients with high-risk early breast cancer. We then did a randomised trial to compare this individually tailored FEC regimen with conventional adjuvant chemotherapy followed by consolidation with high-dose chemotherapy with stem-cell support.

METHODS

525 women younger than 60 years of age with high-risk primary breast cancer were randomised after surgery to receive nine cycles of tailored FEC to haematological equitoxicity with granulocyte colony-stimulating factor (G-CSF) support (n=251), or three cycles of FEC at standard doses followed by high-dose chemotherapy with cyclophosphamide, thiotepa, and carboplatin (CTCb), and peripheral-blood stem-cell or bone-marrow support (n=274). Both groups received locoregional radiation therapy and tamoxifen for 5 years. The primary outcome measure was relapse-free survival, and analysis was by intention to treat.

FINDINGS

At a median follow-up of 34.3 months, there were 81 breast-cancer relapses in the tailored FEC group versus 113 in the CTCb group (double triangular method p=0.04). 60 deaths occurred in the tailored FEC group and 82 in the CTCb group (log-rank p=0.12). Patients in the CTCb group experienced more grade 3 or 4 acute toxicity compared with the tailored FEC group (p<0.0001). Two treatment-related deaths (0.7%) occurred in the CTCb group. Six patients in the tailored FEC group developed acute myeloid leukaemia and three developed myelodysplastic syndrome.

INTERPRETATION

Tailored FEC with G-CSF support resulted in a significantly improved relapse-free survival and fewer grade 3 and 4 toxicities compared with marrow-supported high-dose chemotherapy with CTCb as adjuvant therapy of women with high-risk primary breast cancer.

High-dose chemotherapy (CTM) for breast cancer

We designed and implemented a new mitoxantrone-based high-dose chemotherapy regimen to minimize pulmonary injury (seen in carmustine-based regimens) in patients with breast cancer. One hundred and ninety-one breast cancer patients (99 stage II/IIIA; 27 stage IIIB; 65 stage IV responsive to conventional-dose chemotherapy) were treated with high-dose chemotherapy (CTM) delivered over 4 days (cyclophosphamide (6 g/m2), thiotepa (600 mg/m2), and mitoxantrone (24-60 mg/m2)) followed by autologous hematopoietic stem cell rescue. Stage II/III patients received chest wall radiation and tamoxifen (if hormone-receptor positive) after CTM. The 5-year event-free survival (EFS) for stage II/IIIA patients with 10 or more involved axillary lymph nodes (n = 80) was 62 +/- 12%. Hormone receptor-positive patients with 10 or more nodes did significantly better than negative patients. The EFS for stage IIIB patients at 5 years was 44 +/- 19%; for stage IV patients at 5 years was 17 +/- 10%. Stage IV patients achieving complete response in viscera and/or soft tissue prior to CTM did significantly better than those achieving a partial response. There were six (3%) treatment-related deaths including two due to diffuse alveolar hemorrhage. There were no episodes of delayed interstitial pneumonitis. There were six severe cardiac events in 91 patients (6.6%) but none after instituting mitoxantrone dose-adjustment in the final 100 patients. We conclude that CTM is associated with a low treatment-related mortality and little pulmonary toxicity. CTM produces excellent outcomes in stage II/IIIA patients with 10 or more involved axillary lymph nodes.

Inducible expression of herpes simplex virus thymidine kinase increases sensitivity to ganciclovir but does not enhance bystander effect in breast cancer cells

Delivery of cancer chemotherapy directly to the cancer cell has great appeal. Previous studies using adenoviral transfer of the herpes simplex virus thymidine kinase (HSV-tk) gene followed by ganciclovir (GCV) in an ascites model of breast cancer was successful in reducing tumor burden and prolonging life. However, increasing the viral dose resulted in increased toxicity and host mortality emphasizing the need for an improved therapeutic ratio. To test the hypothesis that enhancement of HSV-tk gene expression would lead to increased sensitivity to GCV and improved bystander effect, we created breast cancer cells expressing HSV-tk under the control of the inducible tetracycline promoter. Using this system, we could inducibly increase gene expression and biochemical activation of HSV-tk. These increased levels of HSV-tk decreased the IC50 to GCV nearly 50-fold. However, the bystander effect was not enhanced by increasing HSV-tk gene expression. We conclude that increased HSV-tk gene expression improves sensitivity to CCV. However, additional measures, such as increased gap junction communication, will likely be needed to enhance the bystander effect and the therapeutic efficacy of this strategy.

Recovery of lymphocyte and dendritic cell subsets after autologous CD34+ cell transplantation

Following high-dose chemotherapy (HDC) and peripheral blood progenitor cell transplantation (PBPCT), there are profound changes in leukocyte homeostasis and the immune system is compromised. Transplantation of purified CD34+ cells may further compromise immune recovery because the grafts are depleted of mature immune cells. However, a detailed monitoring of immune cell reconstitution has not been done. We monitored blood levels of antigen-presenting cells (APC) and of lymphocytes by multi-color flow cytometry at different times post CD34+ PBPCT. We found a rapid normalization of circulating levels of the antigen-presenting CD11c+ dendritic cells (defined as lineage- HLA-DR+ CD11c+ cells). There was a slight over-representation of lin- DR+ CD11c- cells at day 42 post transplantation suggesting that the composition of the APC population might be affected. Normal levels of total T, B and NK lymphocytes were rapidly achieved but the composition of the T cell population was abnormal. Patients had elevated levels of CD8+ T cells at early times and a persistent reduction in levels of naive CD8+ T cells (CD8+ CD4- CD45RA+ CD27+) and of naive CD4+ T cells (CD4+CD3+ CD8- CD45RA+). Thus, we found a rapid recovery of DC after CD34+ PBPCT but the specific numerical defects in naive T cells are likely to be a major cause of immune dysfunction in the patients. Bone Marrow Transplantation (2000) 25, 1249-1255.

Phase I/II trial of cyclophosphamide, mitoxantrone, and escalated doses of carboplatin supported by peripheral-blood stem cells in women with metastatic breast cancer

PURPOSE

To intensify a regimen of high-dose cyclophosphamide, mitoxantrone, and carboplatin that had previously produced high complete and overall response rates in metastatic breast cancer (MBC).

PATIENTS AND METHODS

Forty-four patients with a median age of 43 years (range, 25 to 57 years) and previously untreated MBC who were responding to anthracycline-based or single-agent taxane chemotherapy received cyclophosphamide 1.5 g/m(2)/d and mitoxantrone 16 mg/m(2)/d combined with escalating doses of carboplatin 200 to 500 mg/m(2)/d, each given daily from days -6 to -3. Hematopoiesis was supported by mobilized peripheral-blood stem cells infused on day 0 and by use of granulocyte-macrophage colony-stimulating factor 300 microg/d subcutaneously starting on day 1.

RESULTS

A total of six dose levels of carboplatin were examined. Grades 3 and 4 toxicity occurred in 10 patients and one patient, respectively, with grade 3 toxicity occurring in only five of 31 patients treated with < or = 400 mg/m(2) of carboplatin. Major dose-limiting toxicities were cardiac, pulmonary, and renal. Four patients developed congestive heart failure: two had persistently low ejection fraction 11 and 36 months after peripheral-blood stem-cell transplantation (PBSCT), and two recovered. Hematologic recovery to an absolute neutrophil count of greater than 0.5 x 10(9)/L occurred at a median of 11 days (range, 8 to 25 days) and to a platelet count of greater than 20 x 10(9)/L at a median of 10.5 days (range, 6 to 60 days). There were two toxic deaths from sepsis: one on day 27 (level 5) and one from cardiac arrest on day 42 (level 6).

CONCLUSION

The maximum-tolerated dose of carboplatin was 400 mg/m(2)/d in combination with mitoxantrone 16 mg/m(2)/d and cyclophosphamide 1,500 mg/m(2), all drugs given over 4 days. This regimen is being tested in a phase III trial of high-dose chemotherapy and PBSCT versus standard treatment.

High-dose chemotherapy and stem cell transplantation for patients with stage IV breast cancer without clinically evident disease: correlation of CD34+ selection to clinical outcome

Forty-five patients with metastatic breast cancer without clinically evident disease were treated with thiotepa 750 mg/m2, mitoxantrone 40 mg/m2 and carboplatin 1000 mg/m2 followed by stem cell transplantation to determine the safety and efficacy of CD34+ selection of peripheral blood stem cells. Of these, 15 patients' (group I) stem cells were processed through Baxter Isolex 300 device for CD34+ selection, whereas 30 patients (group II) received unmanipulated stem cells. Toxicity, progression-free survival and survival were compared between these two groups. There was no difference in transfusion requirements, white cell count and platelet recovery and non-hematologic toxicity between the two groups. The survival of patients in group I was 27 months compared to 38 months in group II (P = 0.8). The progression-free survival was 12 months and 13.5 months for group I and group II patients, respectively (P = 0.6). Our results indicate that while there is no adverse effect, there is also no significant advantage of CD34+ selection in terms of progression-free survival and survival in patients with metastatic breast cancer without clinically evident disease. Bone Marrow Transplantation (2000).

Conventional-dose chemotherapy compared with high-dose chemotherapy plus autologous hematopoietic stem-cell transplantation for metastatic breast cancer. Philadelphia Bone Marrow Transplant Group

BACKGROUND

We conducted a randomized trial in which we compared high-dose chemotherapy plus hematopoietic stem-cell rescue with a prolonged course of monthly conventional-dose chemotherapy in women with metastatic breast cancer.

METHODS

Women 18 to 60 years of age who had metastatic breast cancer received four to six cycles of standard combination chemotherapy. Patients who had a complete or partial response to induction chemotherapy were then randomly assigned to receive either a single course of high doses of carboplatin, thiotepa, and cyclophosphamide plus transplantation of autologous hematopoietic stem cells or up to 24 cycles of cyclophosphamide, methotrexate, and fluorouracil in conventional doses. The primary end point was survival.

RESULTS

The median follow-up was 37 months. Of 553 patients who enrolled in the study, 58 had a complete response to induction chemotherapy and 252 had a partial response. Of these, 110 patients were assigned to receive high-dose chemotherapy plus hematopoietic stem cells and 89 were assigned to receive conventional-dose chemotherapy. In an intention-to-treat analysis, we found no significant difference in survival overall at three years between the two treatment groups (32 percent in the transplantation group and 38 percent in the conventional-chemotherapy group). There was no significant difference between the two treatments in the median time to progression of the disease (9.6 months for high-dose chemotherapy plus hematopoietic stem cells and 9.0 months for conventional-dose chemotherapy).

CONCLUSIONS

As compared with maintenance chemotherapy in conventional doses, high-dose chemotherapy plus autologous stem-cell transplantation soon after the induction of a complete or partial remission with conventional-dose chemotherapy does not improve survival in women with metastatic breast cancer.

A phase I dose escalation study of high-dose thiotepa, melphalan and carboplatin (TMCb) followed by autologous peripheral blood stem cell transplantation (PBSCT) in patients with solid tumors and hematologic malignancies

The purpose of this study was to determine the maximum tolerated dose of carboplatin administered with 500 mg/m2 thiotepa and 100 mg/m2 melphalan followed by autologous peripheral blood stem cell (PBSC) infusion in patients with refractory malignancies. Twenty-eight patients with refractory malignancies received high-dose thiotepa (500 mg/m2, melphalan (100 mg/m2) and escalating doses of carboplatin 900-1500 mg/m2) followed by infusion of cryopreserved autologous PBSCs. The maximum tolerated doses were determined to be 500 mg/m2 thiotepa, 100 mg/m2 melphalan and 1350 mg/m2 carboplatin. Two consecutive patients receiving 1500 mg/m2 carboplatin experienced grade 3 mucositis and colitis. Ten patients were enrolled at the maximum tolerated dose and none had grade 3-4 regimen-related toxicity and mortality. All patients at this level experienced grade 1-2 mucositis, 90% grade 1-2 gastrointestinal toxicity, 30% grade 1-2 cardiac and renal toxicity, and 10% experienced grade 1 hepatic toxicity. The median time to achieve a granulocyte count of 0.5x10(9)/l was 9 days (range 7-12 days) and platelet count of 20x10(9)/l was 10 days (range 7-15 days). Of eight patients with stage IV refractory breast cancer, even were evaluable for response, one patient on day 75 will be evaluated soon. Five of seven (71.5%) evaluable patients achieved a complete remission (CR) and two had no response. Of seven patients with non-Hodgkin's lymphoma (n = 4) or Hodgkin's disease (n = 3), five achieved a CR (71.5%). Thiotepa, melphalan and carboplatin can be administered in high doses with tolerable mucositis as the major side-effect. This combination has significant activity in patients with breast cancer, and phase II studies in patients with breast cancer and other chemotherapy-sensitive malignancies are warranted.

High-dose chemotherapy and peripheral blood progenitor cell transplantation in the treatment of breast cancer

Each year in the USA, 180,000 new cases of breast cancer are diagnosed and about 44,000 women die of the disease. Current primary treatment consists of adjuvant chemotherapy and hormone therapy, and statistics show that combination chemotherapy favorably influences the outcomes in both node-negative and node-positive primary disease. However, a significant number of breast cancer patients succumb to the disease, and nearly every patient diagnosed with metastatic breast cancer will be dead within five years. High-dose chemotherapy (HDC) and peripheral blood progenitor cell transplantation (PBPCT) are based upon laboratory and clinical observations of the ability to modify growth properties of quiescent and replicating cancer cells. A large number of HDC and PBPCT regimens have been evaluated for treatment of metastatic breast cancer, and recent autologous bone marrow transplantation data indicate that three HDC regimens (CPB, CTCb and cytoxan and thiotepa) predominate. Unfortunately, negative media coverage surrounding and subsequent to the presentation of preliminary findings reported at the May 1999 American Society of Clinical Oncologists, that were not allowed adequate follow-up time for full analysis of treatment results, has had a detrimental effect on the ability to conduct trials in this area. Several randomized trials have been conducted in both the metastatic and high risk primary disease settings. Thorough analysis of these studies indicates an evaluable improvement in favor of HDC and PBPCT in three of the four randomized studies performed in metastatic breast cancer and two of the four high risk primary studies. Also, initial evaluations found that quality of life appeared comparable in patients receiving either HDC or not. Each randomized trial studied asks a different question and, depending on the intensity of HDC regimen, the intensity and duration of the standard dose chemotherapy control and the schedule of events in relation to induction chemotherapy, the outcomes may be quite variable. Still, certain general trends are indentifiable. HDC alone will not completely cure breast cancer and should be considered as part of an overall therapeutic plan. In some of these studies, significantly longer follow-up is required before definitive analysis can be completed.

High-dose chemotherapy for high-risk primary breast cancer: an on-site review of the Bezwoda study

BACKGROUND

The efficacy of high-dose chemotherapy with progenitor-cell rescue for women with breast cancer is a controversial issue. Although historically controlled trials have suggested a survival advantage for high-dose chemotherapy, several randomised studies have yet to confirm this advantage. Two studies, however, by Bezwoda, of patients with high-risk and metastatic disease, seemed to show a significant survival advantage for high-dose compared with conventional-dose chemotherapy for metastatic and high-risk primary breast cancer.

METHODS

To corroborate the study results before starting a large international confirmatory study, a US team did an on-site review of records for patients in the high-risk study. Limited numbers of records were made available for review, all of which were for patients who received the high-dose-chemotherapy regimen.

FINDINGS

There was much disparity between the reviewed records and the data presented at two international meetings. In addition, the reviewers saw no signed informed consent, and the institutional review committee had no record of approval for the investigational therapy. After the site visit, Bezwoda admitted scientific misconduct by using a different control chemotherapy regimen from that described in presented data.

INTERPRETATION

The Bezwoda study should not be used as the basis for further trials to test the efficacy of the cyclophosphamide, mitoxantrone, etoposide regimen for high-dose chemotherapy in women with high-risk primary breast cancer. This review validates the essential nature of on-site audits, especially in single-institution studies.

A phase II study of two cycles of high-dose chemotherapy with autologous stem cell support in patients with metastatic breast cancer who meet eligibility criteria for a single cycle

Multi-cycle high-dose chemotherapy with autologous stem cell support (HDC-ASCS) may improve the results obtained with single-cycle HDC-ASCS in metastatic breast cancer (MBC). However, the tolerability and efficacy of additional cycles of HDC-ASCS in patients selected using standard eligibility criteria for single cycle HDC-ASCS is uncertain. Twenty-nine patients with MBC and a CR or PR to induction chemotherapy were selected by standard institutional eligibility criteria for single-cycle HDC-ASCS. Cycle 1 HDC-ASCS (cyclophosphamide 6 g/m2; mitoxantrone 70 mg/m2; carboplatin 800 mg/m2) was followed by a planned second cycle (etoposide 1.6 g/m2; thiotepa 800 mg/m2; carboplatin 800 mg/m2 modulated by tamoxifen 120 mg/m2/day x 5 days) with a median interval of 3.2 months. CR rate was 20% after induction chemotherapy and 33% and 54% after HDC cycles I and II, respectively. Sixteen patients (55%) failed to complete HDC cycle II within 200 days because of disease progression, toxicity, inadequate stem cell collection, insurance denials or patient choice. Median progression-free survival (PFS) for all 29 patients entered is 301 days from date of HDC cycle I and actuarial PFS at 2 years is 35%. For the 13 patients who received the two cycles of HDC-ASCS, actuarial PFS at 2 years was 54% (P = NS compared to those receiving only one cycle). These data show that a second cycle of full-dose intensity HDC-ASCS may increase the proportion of patients with MBC that achieve CR and may increase PFS. However, a large proportion of patients that complete HDC-ASCS cycle I may fail to proceed to cycle II in a timely fashion. Bone Marrow Transplantation (2000) 25, 519-524.

Posttransplant adoptive immunotherapy with activated natural killer cells in patients with metastatic breast cancer

Relapse after high-dose chemotherapy is the main cause of therapeutic failure in patients with metastatic breast cancer. Adoptive immunotherapy with interleukin-2 (IL-2) plus activated natural killer cells may eliminate residual disease without excessive toxicity. The authors sought to determine if immunotherapy immediately after transplantation would affect engraftment and the toxicity associated with transplantation. Fifteen consecutive patients with metastatic breast cancer were allocated to three cohorts. Cohort 1 (five patients) received high-dose cyclophosphamide, thiotepa, and carboplatin (CTCb) followed by peripheral blood stem cell infusion and granulocyte colony-stimulating factor at 10 micrograms/kg. Cohort 2 (five patients) received in addition rhIL-2 (2 x 10(6) IU/m2/day) for 4 days intravenously via continuous infusion after peripheral blood stem cell infusion. In cohort 3 (five patients), peripheral blood stem cell transplant was followed by infusion of autologous activated NK cells and rhIL-2 (2 x 10(6) IU/m2/day) for 4 days (via continuous intravenous infusion). Generation of activated NK cells was possible in all patients in cohort 3. All patients has successful engraftment. Median time to absolute neutrophil count more than 0.5 x 10(9)/L was 8 days (range, 8 to 11 days) in cohort 1, 9 days (range, 7 to 11 days) in cohort 2, and 9 days (range, 8 to 9 days) in cohort 3. Median time until the platelet count was more than 20 x 10(9)/L was 14 days (range, 9 to 22 days) in cohort 1, 11 days (range, 6 to 14 days) in cohort 2, and 12 days (range, 11 to 21 days) in cohort 3. All patients developed neutropenic fevers, but the overall toxicity associated with the infusion of IL-2 (cohort 2) or IL-2 plus activated NK cells (cohort 3) did not differ from that observed in cohort 1. Complete responses were achieved in one patient in cohort 1, in two patients in cohort 2, and in one patient in cohort 3. In conclusion, post-transplant adoptive immunotherapy with activated NK cells plus IL-2 is feasible, well tolerated, and does not adversely affect engraftment.

Is there a role for intensive therapy in breast cancer?

With reference to survival, polychemotherapy has been demonstrated to be statistically significantly more effective than monochemotherapy both in the adjuvant setting and in the metastatic situation. Breast cancer demonstrates a dose-response relationship. Chemotherapy used in the conventional dose range should be given with adequate dose-intensity both in the adjuvant setting and for metastatic patients. More dose-intensive combinations are almost always associated with a higher response rate in patients' metastatic disease, but these results have seldom been translated into an improved survival. For marrow requiring high-dose therapy, repeated phase II studies have demonstrated the possibility of a survival tail, which may be due to stage migration and patient selection. At present we have at least 13 ongoing phase III studies in the adjuvant setting and at least 5 ongoing studies in the metastatic situation. These studies will give a definite answer on whether marrow-supported high-dose therapy is better than conventional therapy or if alternative approaches using tailored therapy will result in an equivalent outcome. In the future we must make better use of the present arsenal of drugs and examine the marked inter-individual variations in pharmacokinetic profiles for the drugs. We have to tailor the therapy to the tumour biological profile, in both the primary tumour and metastases with appreciation of heterogeneity and tumour progression. Based on these prerequisites, therapy can be either dose-intensive or in some instances continuous using lower doses.

Stem-cell transplant preparative regimens

Owing to the relatively high probability of recurrent disease in patients receiving hematopoietic stem-cell transplantation (HSCT) for malignancies, further development of new preparative regimens is warranted. Based on the data presented, one can predict that it will continue to be difficult to identify HSCT regimens that are more effective. Incremental improvements are expected to be small, difficult to measure, and will require inclusion of very large numbers of patients. Controlled trials to evaluate the effectiveness of specific treatment regimens for specific groups of patients will require only centers with large numbers of patients or co-operative groups to successfully conduct these studies. Development of HSCT regimens with low mortality and a minimum of morbidity without compromising efficacy are needed. This may be accomplished through the use of agents to protect normal, non-hematopoietic tissues from regimen-related toxicity (RRT), further exploration and expansion of applications of targeted radiolabeled antibody approaches and mixed chimerism approaches. The future holds much work, but great promise, in the development of new HSCT regimens.

Autologous stem-cell transplantation for solid tumors in adults

Over the last decade, high-dose chemotherapy (HDC) with autologous stem-cell transplantation has been explored for a variety of solid tumors in adults, particularly breast cancer, ovarian cancer, and nonseminomatous germ-cell tumors. Response of phase II studies are encouraging in most cases, and, in certain settings, seem clearly superior to historical results of conventional-dose chemotherapy. The value of HDC for adult solid tumors is a highly controversial issue, currently being addressed in large randomized phase II trials. This article reviews the results of HDC in different diseases and depicts potential directions of future progress.

High-dose chemotherapy: is it standard management for any common solid tumor?

High-dose chemotherapy with stem-cell support had as its basis the observation of dose-response relationships for many chemotherapeutic agents in laboratory models. The rationale to explore high-dose treatment in the clinic was further enhanced by several retrospective reviews in the 1980s which suggested delivered dose intensity of treatment was an important determinant of patient outcome. The availability of hematopoietic growth factors and technologic advances in the efficiency of stem-cell collection and administration have made the evaluation of exploring high-dose therapy safe and feasible. However, real questions remain regarding the apparently superior results of this treatment in the management of solid tumors. This paper reviews the results of high-dose chemotherapy in breast, ovarian and small cell lung cancers. Firstly the evidence for a dose-response relationship to chemotherapeutic agents in the 'standard' dosage range is examined. Secondly results of non-randomized and, where available, randomized trials of high-dose chemotherapy (HDCT) with stem-cell support are summarized and finally conclusions regarding the weight of the evidence for use of HDCT as 'standard' treatment are given. In none of these tumors is there sufficient evidence from randomized trials to consider HDCT a standard to be offered to all patients with a given stage of disease. The apparent benefit of HDCT seen in phase II trials could well be explained by such phenomena as stage shifts and patient selection. Many randomized trials in ovary and breast cancer are either ongoing or presented only as abstracts so final results must be awaited to quantify the benefit, if any of HDCT. It is acknowledged, however, that some practitioners already utilize this treatment. We speculate about the differences in philosophical approaches to cancer treatment which might contribute to early acceptance of novel therapies in the absence of adequate randomized data.

Metastatic breast cancer

The unfortunate reality of metastatic breast cancer is that all treatment is palliative in nature. This is a disease that currently has no cure and for which therapy is directed towards accentuating survival and relieving symptoms. Current technology allows the prediction and detection of metastases earlier and with greater accuracy. These achievements need to be consolidated by the discovery of innovative therapies that can alter the inevitable outcome of this disease.

Outcomes of high-dose chemotherapy and autologous stem-cell transplantation in stage IIIB inflammatory breast cancer

PURPOSE

To evaluate the disease-free survival (DFS) and overall survival (OS), prognostic factors, and treatment-related mortality of women with stage IIIB inflammatory breast cancer (IBC) treated with combined modality therapy (CMT) and high-dose chemotherapy (HDCT) with autologous stem-cell transplantation.

PATIENTS AND METHODS

Between 1989 and 1997, 47 consecutive patients with stage IIIB IBC were treated with CMT and HDCT and were the subject of this retrospective analysis. Chemotherapy was administered to all patients before and/or after definitive surgery. Neoadjuvant and adjuvant chemotherapy was administered to 33 and 34 patients, respectively, and 20 patients received both. All patients received HDCT with autologous stem-cell transplantation, and 41 patients received locoregional radiation therapy. Tamoxifen was prescribed to patients with estrogen receptor (ER)-positive cancer.

RESULTS

The mean duration of follow-up from diagnosis was 30 months (range, 6 to 91 months) and from HDCT was 22 months (range, 0.5 to 82 months). At 30 months, the Kaplan-Meier estimates of DFS and OS from diagnosis were 57.7% and 59.1%, respectively. At 4 years, the Kaplan-Meier estimates of DFS and OS from diagnosis were 51.3% and 51.7%, respectively. In a multivariate analysis, the only factors associated with better survival were favorable response to neoadjuvant chemotherapy (P =.04) and receipt of tamoxifen (P =.06); however, the benefit of tamoxifen was only demonstrated in patients with ER-positive breast cancer. At last follow-up, 28 patients (59. 6%) were alive and disease-free. Seventeen patients (36.2%) developed recurrent breast cancer. Seventeen patients died: 15 from disease recurrence and two (4.2%) from treatment-related mortality due to HDCT.

CONCLUSION

In this analysis, the early results of treatment with CMT and HDCT compare favorably with other series of patients with stage IIIB IBC treated with CMT alone. These outcomes must be confirmed with longer follow-up and controlled studies.

FEC mobilized stem cells for high-dose therapy in breast cancer patients. SB6 9401 Study Group

The feasibility of mobilizing peripheral blood stem cells (PBSC) using anthracycline containing polychemotherapy and G-CSF on the first 50 patients randomized to the high-dose arm in the adjuvant SBG 9401 is investigated. The patients were treated with standard FEC (5-fluorouracil 600 mg/m2, epirubicin 60 mg/m2, cyclophosphamide 600 mg/m2) for two courses followed by a modified third FEC course with a C dose of 1200 mg/m2 supported with subcutaneous G-CSF (filgrastim) at 5 mg/kg followed by harvest around day 11. The mean yield of CD34+ cells per patient was 10.6x10(6)/kg (range 2.6-29.1). The side effects after the third course were low and only one patient developed an uncomplicated granulopenic fever. Our data indicated a correlation between number of transfused CD34+ cells and days to neutrophil and platelet recovery. In conclusion, the modified FEC regimen followed by G-CSF is a feasible method for PBSC mobilization in the adjuvant setting.

Single-agent paclitaxel in patients with metastatic breast cancer receiving high-dose chemotherapy with peripheral blood stem cell support

The purpose of this trial was to determine the effects of paclitaxel in patients with newly diagnosed metastatic breast cancer scheduled to receive high-dose chemotherapy with peripheral blood stem cell support. Eighty-four patients received anthracycline-based induction and two doses of paclitaxel at 170 mg/m2 (n = 52) or 250 mg/m2 (n = 32). Eighty-two (98%) received cyclophosphamide and etoposide (n = 50) or paclitaxel and cyclophosphamide (n = 32) with granulocyte colony-stimulating factor for mobilization of peripheral blood stem cells, and 79 (94%) received cyclophosphamide, thiotepa, and carboplatin with peripheral blood stem cell support. One patient (1%) died of infection and 56 (67%) died of progressive disease. For patients with measurable disease, the complete response rate was 21% after induction and 29% after paclitaxel (p = 0.54). Results were compared with those of 125 patients who received the same sequence of therapy without paclitaxel. The complete response rate after high-dose chemotherapy was 54% for patients receiving paclitaxel and 62% for those not receiving paclitaxel (p = 0.60). The probabilities of overall survival and event-free survival at 3 years for patients receiving paclitaxel were 46% and 24%, respectively, compared with 54% and 22%, respectively, for patients not receiving paclitaxel (p = 0.62). Further trials evaluating this dose and schedule of paclitaxel in patients with metastatic breast cancer receiving high-dose chemotherapy are not warranted.

Adjuvant dose-intense chemotherapy with peripheral blood stem cell support in stage II-III breast cancer with five to nine involved axillary lymph nodes

The purpose of this study is to determine outcomes for patients with high-risk nonmetastatic breast cancer undergoing high-dose chemotherapy with peripheral blood stem cell support. Forty-three patients with stage II-III disease, five to nine positive axillary lymph nodes, and a median age of 44 years (range, 27-60 years) were enrolled in a study that included: 1) standard dose doxorubicin, 5-fluorouracil, and methotrexate adjuvant therapy; 2) cyclophosphamide, etoposide, filgrastim, and peripheral blood stem cell harvest; and 3) high-dose cyclophosphamide, thiotepa, and carboplatin (CTCb) followed by peripheral blood stem cell infusion. All 43 patients received doxorubicin, 5-fluorouracil, and methotrexate, 42 (98%) received etoposide, and 41 (95%) received CTCb. Thirty-two patients (74%) are alive, 28 (65%) without relapse at a median of 55 months (range, 41-87 months). Two died (5%) of treatment-related causes, (subclavian catheter complication after etoposide and late radiation pneumonitis), and nine other deaths (21%) were associated with recurrent breast cancer. The probabilities of overall and event-free survival at 4 years were 0.77 and 0.67, respectively, compared with 0.82 and 0.69, respectively, for 72 similar patients with 10 or more positive axillary nodes receiving the same sequence of therapy. Thus, patients with five to nine positive axillary lymph nodes have a similar risk of failure after high-dose chemotherapy and peripheral blood stem cell support as patients with 10 or more positive axillary lymph nodes.

A pharmacokinetic and clinical evaluation of thio-TEPA in combination with cisplatin as first-line chemotherapy for advanced epithelial ovarian carcinoma

The purpose of the study was to explore the combination of thio-TEPA with cisplatin in first-line chemotherapy of epithelial ovarian cancer with special reference to pharmacokinetic and pharmacodynamic relationships. Ten women with advanced disease were included. Pharmacokinetics of thio-TEPA were similar to those in previous studies of single drug therapy with rapid first order elimination of the parent drug and substantial intra- and interindividual variation of the area under the concentration-time curve (AUC). No effects of the drug sequence or repeated treatments were seen on the pharmacokinetics of thio-TEPA, indicating no significant influence from the coadministration of cisplatin on the distribution, metabolism or excretion of thio-TEPA. Pharmacokinetic--pharmacodynamic relationships were less pronounced compared to previous studies, probably due to the influence from cisplatin. Prolongation of treatment intervals, dosage reduction, and withholding of thio-TEPA were required due to myelosuppression, which was the dominating toxicity. Non-hematological toxicity was moderate and easily manageable, cisplatin-related toxicity did not seem to be aggravated. Response rate based on CA 125 fluctuations was 80%, overall median survival was 18 months. In conclusion, the pharmacokinetics of thio-TEPA does not seem to be significantly influenced by concomitant administration of cisplatin in female patients. Manageable toxicity, largely restricted to myelosuppression, and high response rate justify further evaluation of the current regimen.

New developments in high-dose chemotherapy for breast cancer

High-dose chemotherapy with autologous stem cell support as applied to the treatment of breast cancer has shown promise for over 15 years. Three main approaches have been used: (1) standard-dose induction chemotherapy followed by one or two cycles of myeloablative therapy, (2) multicycle nonablative combination chemotherapy, and (3) high-dose sequential chemotherapy using single agents at the maximum tolerated doses in rapid sequence. Each of these approaches has a strong biological rationale and is being pursued in randomized trials. Unfortunately, comparative data are limited and there is only one fully published randomized trial of the use of high-dose chemotherapy in metastatic breast cancer. This small study from South Africa showed a significant improvement in response rate and survival for women receiving high-dose chemotherapy compared to those given standard dose treatment. It is anticipated that results from larger studies in the USA and Europe evaluating the use of high-dose chemotherapy in metastatic breast cancer and in adjuvant treatment of poor-prognosis early-stage disease will be available within the next 2-3 years. A potentially important and related issue is that of tumor contamination of bone marrow and apheresis collections. Current data suggest that finding epithelial tumor cells with sensitive techniques (such as immunohistochemistry or polymerase chain reaction) gives prognostic information. However, it is not clear whether reinfusion of these cells after high-dose chemotherapy contributes to relapse of breast cancer. Unfortunately, understanding of the data is marred by a lack of standardization of assay methodology. Further work is needed to develop a widely accepted method for the detection of circulating tumor cells before the clinical relevance of such a finding can be meaningfully interpreted.