Repetitive cycles of cyclophosphamide, thiotepa, and carboplatin intensification with peripheral-blood progenitor cells and filgrastim in advanced breast cancer patients

Small Split Doses of CD34+ Peripheral Blood Stem Cells to Support Repeated Cycles of Nonmyeloablative Chemotherapy

Cumulative myelosuppression is the main limiting factor for administration of repeated cycles of chemotherapy. We present a case series of five pediatric patients with high-risk solid malignancies who received small split peripheral blood stem cells (PBSC) doses of less than 1 × 10⁶/kg CD34⁺ cells obtained after a single leukapheresis procedure and given after repeated cycles of ICE (ifosfamide, carboplatin, and etoposide) chemotherapy. Mean duration to absolute neutrophil count (ANC) recovery to >1000/mm³ and platelet recovery to >50 × 10³/mm³ was 17.1 and 24.3 days. Using split doses of PBSC prevented prolonged neutropenia after repeated cycles of submyeloablative chemotherapy.

Sulforaphane synergizes with quercetin to inhibit self-renewal capacity of pancreatic cancer stem cells

According to the cancer stem cell hypothesis, the aggressive growth and early metastasis of cancer may arise through dysregulation of self-renewal of stem cells. The objectives of this study were to examine the molecular mechanisms by which sulforaphane (SFN, an active compound in cruciferous vegetables) inhibits self-renewal capacity of pancreatic cancer stem cells (CSCs), and synergizes with quercetin, a major polyphenol and flavonoid commonly detected in many fruits and vegetables. Our data demonstrated that SFN inhibited self-renewal capacity of pancreatic CSCs. Inhibition of Nanog by lentiviral-mediated shRNA expression enhanced the inhibitory effects of sulforaphane on self-renewal capacity of CSCs. SFN induced apoptosis by inhibiting the expression of Bcl-2 and XIAP, phosphorylation of FKHR, and activating caspase-3. Moreover, SFN inhibited expression of proteins involved in the epithelial-mesenchymal transition (beta-catenin, vimentin, twist-1, and ZEB1), suggesting the blockade of signaling involved in early metastasis. Furthermore, the combination of quercetin with SFN had synergistic effects on self-renewal capacity of pancreatic CSCs. These data suggest that SFN either alone or in combination with quercetin can eliminate cancer stem cell-characteristics.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Feasibility of sequential high-dose chemotherapy in advanced pediatric solid tumors

The purpose of this study was to evaluate the feasibility and tumor response of 3 cycles of sequential high-dose chemotherapy (HDCT) in advanced pediatric solid tumor patients. Medical records of 11 children who underwent 2 consequent courses of reduced conditioning HDCT followed by final HDCT with autologous HSC infusion were reviewed in a retrospective manner. Each median time to an absolute neutrophil count > 0.5 x 10(9)/L was 12, 13, and 12 days. Major toxic reactions were fever, infection, and vomiting. One patient experienced transplantation-related mortality. Nine patients showed complete and partial responses to the therapy at 6 months follow-up after final HDCT. Finally, 6 patients are alive without evidence of disease at median follow-up of 24 months. Even though it is a preliminary result, the authors think that this treatment could be a feasible treatment option for advanced pediatric solid tumor patients.

A novel intensive induction therapy for high-risk neuroblastoma utilizing sequential peripheral blood stem cell collection and infusion as hematopoietic support

OBJECTIVE

To determine the feasibility, toxicities, and the response rate (RR) of a dose intensive, submyeloablative, induction chemotherapy protocol termed EPiC (etoposide, carboplatin, and intensive cyclophosphamide) utilizing sequential peripheral blood stem cell (PBSC) collection and infusion as hematopoietic support in children with newly diagnosed Stage 4 neuroblastoma.

PATIENTS AND METHODS

Twenty-five children (age >1 year) with Stage 4 neuroblastoma were enrolled. First and third cycles consisted of cyclophosphamide (4 gm/m2) and carboplatin (400 mg/m2). Second and fourth cycles consisted of carboplatin (1 gm/m2), and etoposide (450 mg/m2). PBSC were collected following Cycles 1, 2, and 3 and reinfused in each subsequent cycle. Following EPiC and surgical resection of the primary tumor, patients proceeded to various consolidation therapies. RR was scored using the International Neuroblastoma Response Criteria.

RESULTS

Using PBSC infusion following EPiC chemotherapy resulted in a dose intensity averaging 85% of intended dose intensity; and in early neutrophil but not platelet recovery. PBSC were adequately collected in all, but one patient. The protocol had minimal non-hematological toxicities. There was one toxic death. The overall RR was 78%, which included PR (partial response) and VGPR (very good partial response). The 5-year event-free survival and overall survival were 44% and 54%, respectively at a median follow-up of 58.6 months.

CONCLUSION

EPiC is a feasible, well-tolerated, sub-myeloablative, induction chemotherapy protocol for children with high-risk neuroblastoma. RR is equivalent to prior published studies, however, with minimal toxicities. Sequential PBSC collection and infusion is feasible even in very young children.

Stem-cell transplantation for the treatment of advanced solid tumors

Over the past two decades, high-dose chemotherapy (HDC) with autologous stem-cell transplantation (ASCT) has been explored for a variety of solid tumors in adults, particularly breast cancer, ovarian cancer and non-seminomatous germ-cell tumors. The results of prospective phase II studies seemed superior in many cases to the outcome expected with standard-dose chemotherapy (SDC). The value of HDC for adult solid tumors remains, in most instances, a controversial issue, currently under the scrutiny of randomized phase III trial evaluation. ASCT pursuing an immune graft-versus-tumor effect has been evaluated in recent years for patients with advanced and refractory solid malignancies. This article reviews the results of the main phase II and III studies of HDC with ASCT, as well as the preliminary experience using allogeneic transplantation for solid tumors.

A phase I/II study of 4 monthly courses of high-dose cyclophosphamide and thiotepa for metastatic breast cancer patients

This pilot phase I/II study intended to determine the maximum tolerated dose of cyclophosphamide and thiotepa administered on four consecutive courses with peripheral blood progenitor cell and granulocyte-colony stimulating factor support, as first-line therapy for hormone-refractory metastatic breast cancer patients. Twenty-eight patients were entered in the study. After two courses of epirubicin (120 mg m(-2)) and cyclophosphamide (2 g m(-2)) followed by granulocyte-colony stimulating factor injection and leukaphereses, patients received four cycles of cyclophosphamide and thiotepa. Each cycle was followed by peripheral blood progenitor cell and granulocyte-colony stimulating factor supports, then repeated every 28 to 35 days. Six escalating dose levels of cyclophosphamide and thiotepa were planned, beginning at cyclophosphamide 1.5 g m(-2) and thiotepa 200 mg m(-2). At least three patients were enrolled for each dose level. Eighteen patients completed the study. The maximum tolerated dose was 3000 mg m(-2) cyclophosphamide and 400 mg m(-2) thiotepa per course. Haematological toxicity was manageable on an outpatient basis and did not increase significantly with dose escalation. Dose-limiting toxicity was chemotherapy-induced immunosuppression, which resulted in one toxic death and two life-threatening infections. Median times to treatment failure and survival were 11 and 26 months, respectively. Three patients were alive, free of disease 30 months after completion of the study. Such therapy allows for high-dose intensity and high cumulative doses on a short period of time with manageable toxicity.

Peripheral blood stem cell support reduces the toxicity of intensive chemotherapy for children and adolescents with metastatic sarcomas

BACKGROUND

To increase the dose intensity (DI) of chemotherapy for pediatric patients with metastatic sarcomas, including the Ewing sarcoma family of tumors (ESFT) and rhabdomyosarcoma (RMS), the authors tested the feasibility of an intensive regimen supported by granulocyte-colony stimulating factor (G-CSF) and peripheral blood stem cells (PBSC).

METHODS

Twenty-three children and adolescents with metastatic sarcomas received vincristine, doxorubicin, cyclophosphamide, ifosfamide, sodium mercaptoethanesulfonate (mensa), and etoposide (VACIME) chemotherapy, consisting of 8 courses of vincristine 2 mg/m(2) on Day 0, doxorubicin 37.5 mg/m(2) per day on Days 0-1, cyclophosphamide 360 mg/m(2) per day on Days 0-4, ifosfamide 1800 mg/m(2) per day on Days 0-4, mesna 2400 mg/m(2) per day, and etoposide 100 mg/m(2) per day on Days 0-4. Doxorubicin was omitted in Courses 7 and 8. G-CSF was given after each course of therapy. Courses of therapy were repeated every 21 days or as soon as hematopoietic recovery permitted. PBSC were collected twice: first, after Course 2 (infused after Courses 3 and 4) and, second, after Course 4 (infused after Courses 5 and 6). Surgical resection followed Course 6, and radiotherapy followed Course 8.

RESULTS

PBSC collections were adequate in 91% of all harvests. The mean DI was 82% (standard deviation, 14%) of the intended DI, which was greater than historic data without PBSC support. Seventeen patients (74%) achieved a complete response (CR), 12 patients with chemotherapy alone and 5 more patients after undergoing surgical resection. Fifteen patients developed progressive disease, with a 2-year event free survival (EFS) rate of 39% (95% confidence interval, 19-59%). Hematopoietic toxicity was severe and cumulative, although it was less than that seen previously without PBSC support.

CONCLUSIONS

PBSC-supported multicycle chemotherapy is a feasible method to increase chemotherapy DI for pediatric patients with metastatic sarcomas. Although the CR rate compared favorably with previously reported response rates, the 2-year EFS rate was similar to that achieved with other intensive regimens.

High-dose sequential epirubicin and cyclophosphamide with peripheral blood stem cell support for advanced breast cancer: results of a phase II study

The aim of this study was to evaluate the feasibility of a high-dose intensity and high-dose density multicycle epirubicin and cyclophosphamide regimen with peripheral blood stem cells (PBSC) and haematopoietic growth factor (G-CSF) support in advanced breast cancer patients. From August 1994 to September 1999, 56 breast cancer patients (8 stage IIIB and 48 stage IV) received 205 courses of cyclophosphamide 3 g x m(-2) and epirubicin 100 mg x m(-2) every 14 days. G-CSF 5 microg x kg(-1) x day(-1) was administered from day 3 to neutrophil recovery. 4 courses were planned. PBSC were collected after course 1, and reinfused after courses 3 and 4, with > or = 2 x 10(6) CD34+ PBSC x kg(-1) required for each reinfusion. 48 patients (86%) received all 4 planned courses. Early withdrawal was consecutive to infectious complications (n = 4), severe asthenia (n = 3), haemorrhagic cystitis (n = 1). A median number of 10.8 x 10(6) CD34+ PBSC x kg(-1) (range, 3-80) was harvested with 1 or 2 apheresis in 48 patients (94%). Median relative dose intensity was 91.3% (range, 72-102%). Grade 4 neutrophil toxicity was observed in 100% of patients. Febrile neutropenia was observed in 40% of courses (median duration 2 days). Red blood cells and platelets had to be transfused in 54% and 27% of courses, respectively. There were no toxic deaths. Objective response rate was 69% in stage IV patients (31/45 evaluable pts), with a 16% complete response rate. Their median progression-free and overall survivals were 22.5 and 37 months, respectively. This epirubicine-containing high-dose regimen appeared feasible, albeit with high toxicity. Time-related progression parameters exceed commonly reported ones. Controlled studies of upfront sequential high-dose chemotherapy are still needed to evaluate its real benefit.

Multiple cycles of dose-intensive chemotherapy with repeated stem cell support as induction treatment in metastatic breast cancer: a feasibility study

The purpose of this trial was to study feasibility and tolerance of a dose-intensive multicyclic alternating induction chemotherapy with repeated stem cell support in a series of 43 metastatic breast cancer patients. Anthracycline-naive patients (n = 21) received cyclophosphamide 2.5 g/m(2) plus doxorubicin 80 mg/m(2) alternating every 14 days with paclitaxel 200-350 mg/m(2) plus cisplatin 120 mg/m(2). Patients who had previously received anthracyclines (n = 22) received cisplatin 120 mg/m(2) plus etoposide 600 mg/m(2) alternating with paclitaxel 200-350 mg/m(2) plus ifosfamide 8 g/m(2). Peripheral blood stem cells were infused after every course except the first, with a median CD34(+) dose of 2.1 x 10(6)/kg per cycle. Positive selection of CD34(+) cells was performed in good mobilizers. The median number of cycles administered was six (4-8), and the time interval between them was 17 days. Median summation dose intensities (SDI) actually administered for the CA-TP and PE-TI protocol were 4.95 and 4.69, respectively (87% of scheduled SDI). There were 15 complete (35%) and 21 partial responses (49%), for an overall response rate of 84% (95% CI, 73%-95%). Infection or neutropenic fever occurred in 50% of the cycles. There was one treatment-related death. After a median follow-up of 26 months, the median event-free-survival was 12 months (95% CI: 10-14) and overall survival was 31 months. These high dose-intensity induction treatments seem to be feasible with sequential stem cell support.

Thrombotic microangiopathy: a new dose-limiting toxicity of high-dose sequential chemotherapy

Ten patients with refractory (n = 8) or early relapsing (n = 2) aggressive non-Hodgkin's lymphoma were enrolled in a pilot study evaluating a high-dose sequential chemotherapy regimen with peripheral blood stem cell (PBSC) support. Five treatment phases were scheduled: phase I (cyclophosphamide + etoposide followed by lenograstim (G-CSF), and a PBSC harvest); phase II (cisplatinum + cytarabine + etoposide followed by lenograstim); phases III and IV (cyclophosphamide + cytarabine + etoposide followed by autologous PBSC infusion and lenograstim); and phase V (carmustine + cytarabine + etoposide + melphalan followed by autologous PBSC infusion and lenograstim). Ten, nine, eight, six and four of the 10 patients received one, two, three, four and five of the five scheduled phases of treatment, respectively. Four patients were withdrawn from the study due to progressive disease and two due to thrombotic microangiopathy (TM). Moreover, in the four patients who completed all treatment phases, an additional case of TM was seen. In all three patients with TM, laboratory studies showed evidence of Coombs negative hemolytic anemia, thrombocytopenia, renal dysfunction and in addition cardiac failure in two patients. TM may be a new dose-limiting toxicity of high-dose sequential chemotherapy followed by repeated PBSC transplantation.

Intensification of adjuvant chemotherapy: 5-year results of a randomized trial comparing conventional doxorubicin and cyclophosphamide with high-dose mitoxantrone and cyclophosphamide with filgrastim in operable breast cancer with 10 or more involved axillary nodes

PURPOSE

To determine whether intensifying the dose of adjuvant chemotherapy improves the outcome of women with primary breast cancer and 10 or more involved axillary nodes.

PATIENTS AND METHODS

Patients (n = 150) were randomized to receive either four cycles of standard doxorubicin 60 mg/m(2) plus cyclophosphamide 600 mg/m(2) every 3 weeks (arm A) or four courses of intensified mitoxantrone 23 mg/m(2) plus cyclophosphamide 600 mg/m(2), with filgrastim 5 g/kg/d from days 2 to 15, every 3 weeks (arm B). Disease-free survival (DFS), distant disease-free survival (DDFS), and overall survival (OS) were determined using life-table estimates.

RESULTS

There were no significant differences in DFS (P =.44), DDFS (P =.67), or OS (P =.99) between the two groups at 5 years; DDFS was 45% (arm A) versus 50% (arm B), and DFS was 41% versus 49%, respectively. Five-year survival was similar in both arms (61% v 60%, respectively). Failure to note an intergroup difference in outcome was unrelated to relative dose-intensity. Analysis of patients with 15 or more positive nodes revealed a significant difference in 5-year DDFS (19% v 49% in arm B; P =.01). Toxicity was generally mild in both groups, with no toxic death. The incidence of febrile neutropenia was low (0.3% v 3%). Alopecia was less frequent in arm B (P <.001).

CONCLUSION

This randomized trial confirms the feasibility of administering mitoxantrone 23 mg/m(2) with cyclophosphamide and filgrastim. Although there was no significant difference between conventional and intensified arms at 5 years, according to subgroup analysis, intensified treatment may decrease the risk of relapse in patients with 15 or more positive nodes compared with doxorubicin an cyclophosphamide.

Repetitive high-dose therapy with cyclophosphamide, thiotepa and docetaxel with peripheral blood progenitor cell and filgrastim support for metastatic and locally advanced breast cancer: results of a phase I study

This phase I study was designed to determine the optimal dosages of a novel repetitive high-dose therapy regimen for patients with metastatic breast cancer (MBC). The planned treatment was three cycles of high-dose cyclophosphamide, thiotepa and docetaxel delivered every 35 days with progressive dose-escalation in successive cohorts. Each cycle was supported by peripheral blood progenitor cells (PBPC) and filgrastim. Eighteen patients were entered into this trial. Of the planned 54 treatment cycles, 44 were delivered and 11 patients completed all three cycles. The dose-limiting toxicities were interstitial pneumonitis and mucositis with moderately severe diarrhea (n = 3) and rash (n = 3). There were no treatment-related deaths. Of the 17 patients with evaluable disease, 16 patients responded with six patients achieving a complete remission and an additional four patients achieving no detectable disease (negative restaging including PET scan) but a persistently abnormal bone scan. At a median follow-up of 12 months, median progression-free survival was 11 months with the median overall survival not reached. The recommended doses for phase II/III studies are cyclophosphamide (4 g/m2), thiotepa (300 mg/m2) and docetaxel (100 mg/m2).

Multiple courses of high-dose ifosfamide, carboplatin, and etoposide with peripheral-blood progenitor cells and filgrastim for small-cell lung cancer: A feasibility study by the European Group for Blood and Marrow Transplantation

PURPOSE

To determine the feasibility and safety of multiple sequential courses of high-dose chemotherapy and peripheral-blood progenitor cells (PBPCs) administered in a multicenter setting to patients with small-cell lung cancer.

PATIENTS AND METHODS

Sixty-nine patients (limited disease, n = 30; extensive disease, n = 39) treated at 15 European centers were scheduled to receive three courses of high-dose chemotherapy with ifosfamide 10 g/m(2), carboplatin 1200 mg/m(2), and etoposide 1200 mg/m(2) (ICE) divided over 4 days at 28-day intervals. PBPCs were harvested before treatment and mobilized with epirubicin 150 mg/m(2) administered via an intravenous bolus divided over 2 days and filgrastim 5 microg/kg/d administered subcutaneously.

RESULTS

The performed leukaphereses (one to five per patient) yielded a median of 16.6 x 10(6)/kg (range, 1.0 to 96.6 x 10(6)/kg) CD34(+) cells, which was sufficient for three reinfusions. Fifty patients (72%) completed the treatment according to schedule. Nine patients completed two courses, and six patients completed one course of treatment. The increase in dose-intensity was 290% that of a standard ICE regimen. The median duration of myelosuppression was similar between courses, namely 4 days (range, 1 to 12 days) for leukocytes less than 0.5 x 10(9)/L and 4 days (range, 0 to 22 days) for thrombocytes less than 20 x 10(9)/L. Febrile neutropenia developed in 66% of courses, severe diarrhea in 14%, mucositis in 10%, and nausea and vomiting in 21% of courses. There were six cases of toxic death (9%), most of which occurred in the first year of accrual and thus were attributable to the learning curve. The antitumor effect of the regimen was reflected in an 86% remission rate (95% confidence interval [CI], 74% to 93%), with 51% of patients achieving a complete response (95% CI, 38% to 63%). Median overall survival was 18 months for patients with limited disease and 11 months for patients with extensive disease.

CONCLUSION

This multiple sequential high-dose ICE regimen could be safely administered on a multicenter basis to patients with small-cell lung cancer. The dose-intensity could be increased to 290% that of standard ICE regimen. The benefit of this approach is currently being tested in a randomized trial that aims to double the long-term rate of survival for patients with small-cell lung cancer.

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.

Repetitive high-dose therapy with ifosfamide, thiotepa and paclitaxel with peripheral blood progenitor cell and filgrastim support for metastatic and locally advanced breast cancer: results of a phase I study

BACKGROUND

This phase I study was designed to determine the optimal dosages of a novel repetitive high-dose therapy regimen for patients with metastatic breast cancer (MBC).

PATIENTS AND METHODS

The planned treatment was three cycles of high-dose ifosfamide, thiotepa and conventional-dose paclitaxel delivered every 28 days with progressive dose-escalation in successive cohorts. Each cycle was supported by peripheral blood progenitor cells (PBPC) and filgrastim.

RESULTS

Twenty-three patients were entered into this trial. Of the planned 69 treatment cycles, 59 were delivered and fifteen patients completed all three cycles. The dose-limiting toxicities were renal tubular acidosis, encephalopathy, mucositis and enterocolitis. There was one treatment-related hemorrhagic death.

CONCLUSIONS

The recommended doses for phase II or III studies are ifosfamide (10 g/m2), thiotepa (350 mg/m2) and paclitaxel (175 mg/m2).

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

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

High-dose therapy with peripheral blood stem cell (PBSC) support using an innovative mobilization regimen in patients with high-risk primary or chemoresponsive metastatic breast cancers

High-dose therapy followed by peripheral blood stem cell (PBSC) support was performed in 29 patients with primary high-risk (Group I) or chemoresponsive metastatic (Group II) breast cancer patients. Group I patients had received PBSC mobilization within 4 weeks of modified radical mastectomy. Group II patients had to achieve minimal residual disease (MRD) by induction chemotherapy before being considered eligible for PBSC mobilization and high-dose therapy. An innovative FE120C regimen (5-FU 600 mg/m2, i.v., day 1; epirubicin 120 mg/m2, i.v., day 1; cyclophosphamide 600 mg/m2, i.v., day 1) plus G-CSF (300 microg/day, subcutaneous injection for 9 days, from day 4 post-FE120C) was used to mobilize PBSCs. After high-dose CTCb (cyclophosphamide 6,000 mg/m2, thiothepa 500 mg/m2, carboplatin 800 mg/m2, in 4 days), patients received PBSC infusion and daily C-CSF 300 microg subcutaneous injection. There were 19 and 16 patients enrolled into Group I and Group II, respectively. Ten of the Group II patients had achieved minimal residual disease (MRD) after induction chemotherapy. The median numbers of mobilized total CD34 + cells for Group I and Group II patients were 27.3 (9.2 to 114.1) x 10(6)/kg and 17.1 (5.9 to 69.1) x 10(6)/kg respectively. The median time to neutrophil recovery (ANC > or = 500/microL) was 8 and 9 days in Group I and II, respectively. The median time to platelet recovery (> or = 50,000/microL) was 10 and 15 days in Group I and II, respectively. No major treatment-related toxicities were noted. In Group I, 13 out of 19 patients (68.4%; 43-87%, 95% C.I.) remained recurrence-free with a median follow-up of 31 months (6 + to 55 + months). In Group II, 3 out of 10 patients (30%; 7-65%, 95% C.I.) remained progression-free at 33 +, 35 +, 39 + months from induction therapy. We suggest that the FE120C plus G-CSF is an effective and innovative regimen for PBSC mobilization in breast cancer patients, and high-dose CTCb therapy with PBSC support is a safe and well-tolerated treatment modality.