High-dose cisplatin, etoposide, and cyclophosphamide with autologous stem cell reinfusion in patients with responsive metastatic or high-risk primary breast cancer

High-Dose Chemotherapy and Autologous Stem Cell Rescue for Metastatic Breast Cancer

During 1990-1999, we treated 60 patients with breast cancer who had distant metastases with high-dose chemotherapy and autologous stem cell rescue (HDC) after they had responded to induction chemotherapy. HDC regimens were MiTepa (60 mg/m2 mitoxantrone by continuous intravenous infusion over 3 days plus 300 mg/m2 thiotepa intravenously over 2 hours daily x 3 days) and ICE (12 g/m2 ifosfamide, 1800 mg/m2 carboplatin, 2 g/m2 etoposide; all 3 by continuous intravenous over 4 days). At a median follow up >8 years, the median failure-free survival (FFS) was 13.9 months, median overall survival (OS) 29.1 months, 5-year FFS 12%s and 5-year OS 25%. Thirty-three patients underwent tandem (T) transplants; 27 underwent a single (S) HDC. Median ages for these 2 groups were 45 and 48 years; bone and liver metastases were more prevalent in the T cohort, whereas lung metastases were more prevalent in the S cohort. At a median follow up of 6.5 years for the S group and >9 years for the T group, there were 52 deaths. FFS was better for T: median 15.7 versus 7.7 months (p2 = 0.010) as was OS: median 32.7 versus 17.7 months, 2-year survival 68% versus 41%, and 5-year survival 32% versus 15% (p2 = 0.010). As a group, patients with distant metastatic breast cancer who underwent tandem transplants had a better posttransplant survival than patients who underwent a single HDC.

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.

Predictors of long-term outcome following high-dose chemotherapy in high-risk primary breast cancer

We report on a predictive model of long-term outcome in 114 high-risk breast cancer patients treated with high-dose chemotherapy between 1989 and 1994. Paraffin-blocks from 90 of the 114 primaries were assessed for the presence of five risk factors: grade, mitotic index, protein expression of p53, HER2/neu, and oestrogen/progesterone receptor status; we could analyse the effect of risk factors in 84 of these 90 tumours. Seven-year relapse-free and overall survival was 58% (95% confidence interval 44-74%) and 82% (95% confidence interval 71-94%) vs 33% (95% confidence interval 21-52%) and 41% (95% confidence interval 28-60%) for patients whose primary tumours displayed > or =3 risk factors vs patients with < or =2 risk factors. For the entire group of 168 high-risk breast cancer patients, inflammatory stage IIIB disease and involved post-mastectomy margins were associated with decreased relapse-free survival and overall survival; patients treated with non-doxorubicin containing standard adjuvant therapy experienced worse overall survival (RR, 2.08; 95% confidence interval 1.04 to 4.16; P=0.04), while adjuvant tamoxifen improved overall survival (RR, 0.65; 95% confidence interval 0.41-1.01; P=0.054). Future trial designs and patient selection for studies specific for high-risk breast cancer patients should include appropriate prognostic models. Validation of such models could come from recently completed randomised, prospective trials.

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.

A phase I trial of high-dose paclitaxel, cyclophosphamide and mitoxantrone with autologous blood stem cell support for the treatment of metastatic breast cancer

The aim of this phase I study was to determine the dose limiting toxicity (DLT), maximum tolerated dose (MTD) and efficacy of a new combination of cyclophosphamide (6 g/m2), mitoxantrone (70 mg/m2), with dose escalation of paclitaxel (TaxolR) at a starting dose of 250 mg/m2 given intravenously over 3 h in a transplantation setting. Patients with metastatic breast cancer and chemosensitive disease were eligible. The autologous blood stem cell re-infusion and subsequent recovery occurred in an out-patient setting. 50 patients were enrolled, but 10 withdrew. 40 completed the entire protocol. At 400 mg/m2 paclitaxel administered over 3 h, 3 of 6 patients experienced serious adverse events: approximately 20-40 min after completion of infusion, diaphoresis, bradycardia mild hypotension and diarrhoea occurred; 2 patients lost consciousness for a few minutes. An extended infusion schedule delivering 400 mg/m2 paclitaxel over 6 h rather than 3 h was initiated at this level without patients experiencing this DLT. At the next dose of 450 mg/m2 paclitaxel over 6 h, the same DLT was seen as at 400 mg/m2 paclitaxel over 3 h and, therefore, MTD was reached. Time to recovery for the absolute neutrophil count > or = 0.5 x 10(9)/l was 10-19 days (median 12 days); and for platelets > or = 20 x 10(9)/l was 18-20 days (median 11.5 days). 21 patients developed neutropenic fever that required intravenous antibiotics and re-admission; the transfusion frequency for packed red blood cell was 0-5 units (median 2 units) and for platelets, 1-5 encounters (median 2). 13 complete responses, 1 patient with no evidence of disease and 19 partial remissions were documented. The dose of 400 mg/m2 at an infusion rate of 6 h will be used for the ongoing phase II study to evaluate efficacy and toxicity further.

Hematopoietic progenitor cell transplantation in breast cancer: current status and future directions

Breast cancer remains the second leading cause of cancer death despite numerous advances in medical science. In vitro, preclinical, and clinical trials have shown that chemotherapy dose intensity is an important component of therapy. Many clinical trials addressing the use of high-dose chemotherapy and hematopoietic cellular rescue have been conducted over the past decade. Early trials undertaken in heavily pretreated patients who had metastatic disease were associated with high treatment-related mortality rates; good response rates were noted but overall survivals were short. Subsequent technological advances, including the use of recombinant hematopoietic growth factors and peripheral blood progenitor cells as the source of cellular rescue, have dramatically lowered the morbidity and mortality of the procedure, as well as shortened hospital stay and markedly reduced cost. As a result, the high-dose chemotherapy approach has been used earlier in the disease course, both in patients with metastatic disease who were responding and in the adjuvant setting in patients at high risk for relapse. Results of many of these phase II trials are extremely encouraging, and phase III prospective, randomized trials comparing autotransplant to conventional approaches are currently under way. This review discusses past, current, and future initiatives of this modality. Included is a discussion of new preparative regimens, the addition of agents such as biochemical modifiers to enhance antitumor activity, and issues regarding timing of autotransplant, stem cell technology, use of allogeneic stem cells, and posttransplantation therapies.

Much ado about not...enough data: high-dose chemotherapy with autologous stem cell rescue for breast cancer

High-dose chemotherapy with autologous bone marrow or stem cell rescue (HDC/ASCR) has been proposed as a promising treatment strategy for breast cancer. Despite the frequency with which this procedure is performed, the role of HDC/ASCR in the treatment of breast cancer remains undefined. The purpose of this review is to examine the rationale for the procedure, the research progress to date, and the limitations of available data. A literature search of Medline from January 1966 through May 1997, CancerLit from January 1983 through May 1997, and Current Contents through May 1997 identified more than 600 English language papers or abstracts on this topic. Our review focuses on the preclinical and clinical data that explore the concept of chemotherapy dose intensity and the role of dose intensity in treating breast cancer. HDC/ASCR is based on the hypothesis that high-dose chemotherapy will overcome drug resistance, eradicate metastatic disease, and increase the proportion of women with breast cancer who are "cured." To date, results from only one phase 3 trial of HDC/ASCR compared with more conventional therapy have been published. Phase 2 and some phase 3 data on HDC/ASCR in the treatment of high-risk primary breast cancer and metastatic breast cancer are discussed. However, the results are inconclusive. The completion of national and international randomized trials is urgently needed to establish definitively the role of HDC/ASCR in the treatment of breast cancer.

Standard-dose recombinant human granulocyte colony-stimulating factor (rhG-CSF) allows safe and repeated administration of high-dose cyclophosphamide, etoposide, and cisplatin (CEP)

High-dose chemotherapy often requires hematopoietic progenitor cell reinfusion, but drugs with extramedullary dose-limiting toxicity may be administered in the high-dose range by simple growth factor support. In this study, we evaluated the feasibility and toxicity of a three-drug high-dose regimen supported by recombinant human granulocyte colony-stimulating factor (rhG-CSF). Ten patients with histologically proven malignancy were enrolled. Eight had breast cancer, one non-Hodgkin's lymphoma, and one a mediastinal tumor of unknown origin. The regimen included cyclophosphamide (C) 5 g/m2, etoposide (E) 1.5 g/m2, and cisplatin (P) 150 mg/m2 (CEP), administered in a 3-day schedule followed by rhG-CSF, 300 micrograms once a day, beginning from day +5 (36 h after the end of chemotherapy). The cycle was repeated as clinically needed up to three times. After the first course, hematologic recovery was rapid and complete without documented infections, and no relevant extramyeloid toxicities were observed. Eight of 10 patients received a second course with comparably low toxicity, and three of them received a third course. We concluded that CEP therapy can be administered safely and even repeatedly, by simple growth factor support, in good performance status cancer patients.

Effect of CD34+ Selection and Various Schedules of Stem Cell Reinfusion and Granulocyte Colony-Stimulating Factor Priming on Hematopoietic Recovery After High-Dose Chemotherapy for Breast Cancer

We evaluated the effects of various schedules of peripheral blood stem cell (PBSC) reinfusion, granulocyte colony-stimulating factor (G-CSF ) priming, and CD34+ enrichment on hematopoietic recovery in 88 patients with advanced breast cancer treated with high-dose chemotherapy, consisting of cisplatin 250 mg/m2, etoposide 60 mg/kg, and cyclophosphamide 100 mg/kg. PBSC (≥7.5 × 108 nucleated cells/kg) were collected following priming with G-CSF and were either immediately cryopreserved (48 patients; cohorts A and B) or were first processed for CD34+ enrichment (40 patients; cohorts C and D). Patients in cohorts A and C received PBSC on day 0; patients in cohorts B and D received 25% of their nucleated cells on day −2 and 75% on day 0 (split reinfusion). Patients in cohorts A, B, and C were primed with G-CSF 10 μg/kg, subcutaneously (SC), once a day; patients in cohort D were primed with 5 μg/kg G-CSF, SC, twice daily (bid). Bid administration of G-CSF yielded 2.3 to 4.7 × higher numbers of CD34+ cells in the PBSC product than the same total dose given once a day (P = .002). Reinfusion of 25% of unselected PBSC on day −2 (median, 2.26 × 108/kg nucleated cells [range, 1.7 to 3.3 × 108/kg]) with the remaining cells reinfused on day 0 resulted in earlier granulocyte recovery to ≥500/μL when compared with reinfusion of all stem cells on day 0 (group B, median of 8 days [range, 7 to 11] v group A, 10 days [range, 8 to 11], P = .0003); no schedule-dependent difference was noted in reaching platelet independence (group B, 11.5 days [range, 5 to 21]; group A, 12 days [range, 8 to 24], P = not significant). Split schedule reinfusion of CD34+-selected PBSC did not accelerate granulocyte recovery. In groups D and C, the median number of days to granulocyte recovery was 12 (range, 8 to 22) and 11.5 (range, 9 to 13); patients became platelet independent by day 15 (range, 6 to 22) and 14 (range, 12 to 23), respectively. CD34+-selected PBSC rescue decreased the incidence of postreinfusion nausea, emesis, and oxygen desaturation in comparison to unselected PBSC reinfusion (P ≤ .005 for each). Hematopoietic recovery may be accelerated by earlier reinfusion of ≈ 2.26 × 108/kg unselected nucleated cells. Earlier recovery may be triggered by components other than the progenitors included in the CD34+ cell population. Sustained hematopoietic recovery can also be achieved with CD34+-selected PBSC alone. Dosing of G-CSF on a bid schedule generates higher CD34+ cell yield in the leukapheresis product. Whether even earlier “sacrificial” reinfusion of approximately 2 × 108/kg unselected nucleated cells concomitant with the administration of high-dose chemotherapy would reduce the duration of absolute granulocytopenia further while initiating sustained long-term hematopoietic recovery will require further investigation.

Effect of CD34+ Selection and Various Schedules of Stem Cell Reinfusion and Granulocyte Colony-Stimulating Factor Priming on Hematopoietic Recovery After High-Dose Chemotherapy for Breast Cancer

We evaluated the effects of various schedules of peripheral blood stem cell (PBSC) reinfusion, granulocyte colony-stimulating factor (G-CSF ) priming, and CD34+ enrichment on hematopoietic recovery in 88 patients with advanced breast cancer treated with high-dose chemotherapy, consisting of cisplatin 250 mg/m2, etoposide 60 mg/kg, and cyclophosphamide 100 mg/kg. PBSC (≥7.5 × 108 nucleated cells/kg) were collected following priming with G-CSF and were either immediately cryopreserved (48 patients; cohorts A and B) or were first processed for CD34+ enrichment (40 patients; cohorts C and D). Patients in cohorts A and C received PBSC on day 0; patients in cohorts B and D received 25% of their nucleated cells on day −2 and 75% on day 0 (split reinfusion). Patients in cohorts A, B, and C were primed with G-CSF 10 μg/kg, subcutaneously (SC), once a day; patients in cohort D were primed with 5 μg/kg G-CSF, SC, twice daily (bid). Bid administration of G-CSF yielded 2.3 to 4.7 × higher numbers of CD34+ cells in the PBSC product than the same total dose given once a day (P = .002). Reinfusion of 25% of unselected PBSC on day −2 (median, 2.26 × 108/kg nucleated cells [range, 1.7 to 3.3 × 108/kg]) with the remaining cells reinfused on day 0 resulted in earlier granulocyte recovery to ≥500/μL when compared with reinfusion of all stem cells on day 0 (group B, median of 8 days [range, 7 to 11] v group A, 10 days [range, 8 to 11], P = .0003); no schedule-dependent difference was noted in reaching platelet independence (group B, 11.5 days [range, 5 to 21]; group A, 12 days [range, 8 to 24], P = not significant). Split schedule reinfusion of CD34+-selected PBSC did not accelerate granulocyte recovery. In groups D and C, the median number of days to granulocyte recovery was 12 (range, 8 to 22) and 11.5 (range, 9 to 13); patients became platelet independent by day 15 (range, 6 to 22) and 14 (range, 12 to 23), respectively. CD34+-selected PBSC rescue decreased the incidence of postreinfusion nausea, emesis, and oxygen desaturation in comparison to unselected PBSC reinfusion (P ≤ .005 for each). Hematopoietic recovery may be accelerated by earlier reinfusion of ≈ 2.26 × 108/kg unselected nucleated cells. Earlier recovery may be triggered by components other than the progenitors included in the CD34+ cell population. Sustained hematopoietic recovery can also be achieved with CD34+-selected PBSC alone. Dosing of G-CSF on a bid schedule generates higher CD34+ cell yield in the leukapheresis product. Whether even earlier “sacrificial” reinfusion of approximately 2 × 108/kg unselected nucleated cells concomitant with the administration of high-dose chemotherapy would reduce the duration of absolute granulocytopenia further while initiating sustained long-term hematopoietic recovery will require further investigation.

High-dose chemotherapy with autologous stem cell rescue in breast cancer

BACKGROUND

Because metastatic breast cancer is a lethal disease despite some responsiveness to systemic chemotherapy, high-dose chemotherapy with autologous stem cell rescue is being utilized with increasing frequency. This analysis was undertaken to determine the outcome for such patients treated with intensive chemotherapy between 1989-1994, at the Hoag Cancer Center in Newport Beach, CA.

METHODS

During 1989, only patients with metastatic disease who had failed more than two standard breast cancer chemotherapy regimens were considered eligible for such treatment. They received high-dose BCNU/cyclophosphamide/cisplatinum chemotherapy with autologous bone marrow rescue. After January 1990, patients with metastatic disease were eligible only if they had received limited prior chemotherapy and demonstrated responsiveness to induction chemotherapy. Beginning June 1990, patients with metastatic disease were to receive mitoxantrone and thiotepa (MiTepa) followed by peripheral blood stem cell rescue, then ifosfamide, carboplatin and etoposide (ICE) chemotherapy followed by peripheral blood stem cell rescue. High-risk adjuvant patients were to receive one course of ICE followed by rescue.

RESULTS

Between 1/89-12/94, 48 breast cancer patients underwent 65 intensive chemotherapy treatments followed by autologous stem cell rescue. During 1989, three of the eight patients with metastatic disease died within 60 days because of therapy-related complications. The longest failure-free survival (FFS) of these eight was 12.2 months, and the longest overall survival (OS) 20.5 months. Since 1/90, one physician has treated 24 patients with metastatic breast cancer, 17 of whom actually underwent two successive transplants with MiTepa/ICE. For the latter group, median FFS is 23.2 months; median OS is 39.7 months. There were no acute deaths, but two patients died > 60 days after initial transplant from therapy-related complications, veno-occlusive disease (5.2 months) and myelodysplastic syndrome (30.5 months), while five died of progressive disease at 22.5, 32.8, 39.4, 46.3, and 51.3 months. For the 24 metastatic patients treated 1990-1994, 1-, 2-, and 3-year FFS rates are 86%, 40%, and 17%, respectively, while OS rates are 91%, 80%, and 65%. Of 11 patients treated in the adjuvant setting, only one has relapsed (9.8 months) with follow-up from 3-61 months.

CONCLUSIONS

Modifications made in the program, including selection of patients responsive to induction chemotherapy, transfusion of peripheral blood stem cells, implementation of hematopoietic colony stimulating factors, and use of tandem intensive treatments has been associated with a low rate of acute morbidity and encouraging survival rates.

High-dose chemotherapy with autologous stem cell rescue for breast cancer: yesterday, today and tomorrow

Metastatic breast cancer remains incurable by conventional means and is the second leading cause of all cancer deaths in women in the United States. Laboratory and clinical studies have shown chemotherapy dose intensity may be important in breast cancer therapy, and therefore clinical trials have been investigating high-dose chemotherapy (HDC) with autologous stem cell rescue (ASCR) for the past decade. Initial Phase I trials in heavily pretreated patients demonstrated good response rates but short survival times. The next generation of trials used HDC as initial treatment for metastatic breast cancer and showed improved results. Most recently, patients receive HDC after "induction" chemotherapy to minimize tumor burden prior to HDC. Results from these most recent trials are encouraging, with complete remissions (CR) achievable in at least half of patients and long-term survivors noted. An ongoing randomized trial of HDC versus conventional chemotherapy should answer whether HDC is superior to conventional chemotherapy for metastatic breast cancer. Based on encouraging data from a preliminary trial, two ongoing randomized trials are comparing HDC versus conventional chemotherapy in high-risk primary breast cancer. Technological improvements, better supportive care and experience have all contributed to decrease the morbidity and mortality of this procedure. Additionally, hospitalizations have become shorter and costs may be decreasing. This review will discuss the issues pertinent to this modality in the past and present, including chemotherapy regimens, stem cell technology and related issues, outcomes, ongoing trials and future directions for consideration.