Dose escalation of paclitaxel with high-dose cyclophosphamide, with analysis of progenitor-cell mobilization and hematologic support of advanced ovarian cancer patients receiving rapidly sequenced high-dose carboplatin/cyclophosphamide courses

Lessons learned from a decade of clinical trials of high-dose chemotherapy in ovarian cancer

Ovarian cancer is one of the most chemosensitive solid tumors and therefore a good example to explore high-dose chemotherapy (HDC). Interest in pursuing this treatment arose in the late 1980s following the success of HDC in treating hematological cancers and improvements in supportive care with peripheral blood stem cells. Experience from phase II trials and analysis of Bone Marrow Transplant Registry data led to the launch of several randomized phase III trials in the late 1990 s. Initial enthusiasm for this treatment was in part due to the preliminary positive data emerging from HDC in breast cancer. Five randomized trials of HDC in ovarian cancer have been conducted and all experienced difficulty in recruitment. Their different designs and results are reviewed, as well as some of the lessons that have been learned about HDC in solid tumors in the last decade.

Phase III Trial of High-Dose Sequential Chemotherapy With Peripheral Blood Stem Cell Support Compared With Standard Dose Chemotherapy for First-Line Treatment of Advanced Ovarian Cancer: Intergroup Trial of the AGO-Ovar/AIO and EBMT

Purpose

Although ovarian cancer is one of the most chemotherapy-sensitive solid tumors, cure after radical surgery and chemotherapy is uncommon. A randomized trial comparing high-dose sequential chemotherapy with peripheral blood stem cell (PBSC) support with platinum-based combination chemotherapy was conducted to investigate whether dose-intensification improves outcome.

Patients and Methods

One hundred forty-nine patients with untreated ovarian cancer were randomly assigned after debulking surgery to receive standard combination chemotherapy or sequential high-dose (HD) treatment with two cycles of cyclophosphamide and paclitaxel followed by three cycles of HD carboplatin and paclitaxel with PBSC support. HD melphalan was added to the final cycle. The median age was 50 years (range, 20 to 65 years) and International Federation of Gynecology and Obstetrics stage was IIb/IIc in 4%, III in 78%, and IV in 17%.

Results

Seventy-six percent of patients received all five cycles in the HD arm and the main toxicities were neuro-/ototoxicity, gastrointestinal toxicity, and infection and one death from hemorrhagic shock. After a median follow-up of 38 months, the progression-free survival was 20.5 months in the standard arm and 29.6 months in the HD arm (hazard ratio [HR], 0.84; 95% CI, 0.56 to 1.26; P, .40). Median overall survival (OS) was 62.8 months in the standard arm and 54.4 months in the HD arm (HR, 1.17; 95% CI, 0.71 to 1.94; P, .54).

Conclusion

This is the first randomized trial comparing sequential HD versus standard dose chemotherapy in first-line treatment of patients with advanced ovarian cancer. We observed no statistically significant difference in progression-free survival or OS and conclude that HD chemotherapy does not appear to be superior to conventional dose chemotherapy.

Phase I/II trial of multicycle high-dose chemotherapy with peripheral blood stem cell support for treatment of advanced ovarian cancer

Ovarian cancer is chemosensitive, but most patients with advanced disease die from tumor progression. As 25% of the patients can be cured by chemotherapy, it is reasonable to evaluate high-dose chemotherapy (HDCT). Forty-eight patients with untreated ovarian cancer were entered in a multicenter phase I/II trial of multicycle HDCT. Median age was 46 (19-59 years); International Federation of Gynecology and Obstetrics-stage was III in 79% and IV in 21%; 31% had residual disease >1 cm after surgery. Two courses of induction/mobilization therapy with cyclophosphamide (250 mg/m2) and paclitaxel (250 mg/m2) were used to collect peripheral blood stem cells. HDCT consisted of two courses of carboplatin (area under curve (AUC) 18-22) and paclitaxel followed by one course of carboplatin and melphalan (140 mg/m2) with or without etoposide (1600 mg/m2). Main toxicity was gastrointestinal. Limiting carboplatin to AUC 20 and eliminating etoposide resulted in manageable toxicity (69% without grade 3/4 toxicity). One patient died from treatment-related pneumonitis. At 8 years median follow-up, median progression-free-survival (PFS) and overall survival (OS) is 13.3 and 37.0 months. Five-years PFS and OS is 18 and 33%. Multicycle HDCT is feasible in a multicenter setting. A European phase III trial based on this regimen is evaluating the efficacy of HDCT.

Randomized Phase II trial of two high-dose chemotherapy regimens with stem cell transplantation for the treatment of advanced ovarian cancer in first remission or chemosensitive relapse: a Southwest Oncology Group study

OBJECTIVES

To evaluate response rates, progression-free survival (PFS), overall survival (OS), and toxicity of two high-dose chemotherapy regimens with stem cell rescue used to treat patients with recurrent or persistent stage III/IV ovarian cancer, with the goal of taking one forward into a Phase III comparison with conventional therapy.

METHODS

Patients under 65 with clinically or pathologically persistent disease after initial chemotherapy or those relapsing >6 months after a complete remission (CR) were randomized to CMC carboplatin (1500 mg/m(2)), mitoxantrone (75 mg/m(2)), and cyclophosphamide (120 mg/kg)], or CTC: [cisplatin (165 mg/m(2)), thiotepa (600 mg/m(2)), and cyclophosphamide (5625 mg/m(2))] with stem cell rescue.

RESULTS

Of 67 randomized, the 32 and 26 eligible in the CMC and CTC arms were matched including age (median 49), maximum tumor diameter, and disease status at transplant. Low-risk disease (maximum diameter disease <or= 0.5 cm and platinum sensitivity) was demonstrated in only approximately one-half of the patients. There were two treatment-related deaths in each arm. The median PFS was 13 and 8 months, respectively, for the CMC and CTC arms. The median OS was 29 and 22 months for the CMC and CTC arms. In a multivariate analysis of PFS, normal CA125 at transplant and CR to primary therapy were significant; for OS, normal CA125 and platinum sensitivity were significant.

CONCLUSIONS

The CMC regimen was the superior regimen. However, few patients were long-term progression-free survivors. A clinical CR to primary therapy and a normal CA125, seen in a minority of patients, were requirements for a favorable outcome.

Phenotypic and immunologic characteristics of docetaxel-mobilized peripheral blood stem cells in mice

Effective mobilization of peripheral blood stem cells is vital for transplantation of patients after high-dose chemotherapy and provides a convenient source of stem cells for genetic engineering and other studies, but optimal mobilization strategies have not been defined. Recent studies show that in the presence of recombinant human granulocyte colony-stimulating factor (rhG-CSF), docetaxel (DXT) is an effective mobilization agent. This study was performed to evaluate the phenotype and immunologic properties of DXT-mobilized stem cells. Administration of DXT + rhG-CSF to normal C57Bl/6 mice induced a 75-fold increase in blood hematopoietic progenitors and a significant increase in both CD3(+) (T cell) and DX5(+) [natural killer (NK)] cells when compared to untreated mice. The cytotoxicity of DXT + rhG-CSF-mobilized cell populations against YAC-1 and B16F10 cell lines was not significantly different from that of untreated mice. When compared to cyclophosphamide + rhG-CSF, DXT + rhG-CSF-mobilized cell populations yielded a greater number of T and NK cells, with significantly higher cytotoxic effector function. These results suggest that DXT + rhG-CSF-mobilized PBSCs retain potent immunologic capacity with a high number of the functional cellular subsets than those normally present in peripheral blood, which may be important in maintaining the antitumor immunity after transplantation.

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

OBJECTIVES

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

PATIENTS AND METHOD

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

RESULTS

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

CONCLUSIONS

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

Intensive sequential dose dense chemotherapy with stem cell support as first-line treatment in advanced ovarian carcinoma: a phase II study

From August 1995 to December 1997, 15 patients with stage III-IV ovarian cancer were treated with outpatient intensive chemotherapy with G-CSF and stem cell support. The first cycle consisted of cyclophophamide IV 6 g/m(2); second, third, fourth and fifth paclitaxel 250 mg/m(2) and the sixth and seventh carboplatin AUC 18. CD34(+) cells were collected after the first cycle and reinfused after completion of cycles 6 and 7. Fourteen patients had stage IIIc and one patient had stage IV disease with liver metastases. All patients underwent laparotomy to maximize tumor debulking. This was optimal in eight patients and suboptimal in seven patients. Second-look surgery was performed in 14 patients. All patients had macroscopic complete responses and 10 patients had complete histologic response. Median follow-up was 48 months (range, 20 to 62). Twelve patients had further progression at a median of 27 months (range, 9 to 42) and nine are alive, three without evidence of disease progression. This pilot study shows that dose-dense chemotherapy with paclitaxel and carboplatin is associated with low toxicity and may improve the outcome of patients with poor prognosis ovarian cancer.

Mobilization of peripheral blood stem cells with paclitaxel and rhG-CSF in high-risk breast cancer patients

Preclinical studies have demonstrated the rapid and efficient mobilization of hematopoietic peripheral blood stem cells (PBSC) in a mouse model using the combination of paclitaxel with recombinant human granulocyte colony-stimulating factor (rhG-CSF). On the basis of these results, a clinical trial was initiated using rhG-CSF with paclitaxel for PBSC mobilization in high-risk breast cancer patients. The mobilized PBSC were evaluated for CD34(+) cell number, mononuclear cell content, and clonogenic potential. One-hundred and seventeen breast cancer patients received paclitaxel (300 mg/m(2)) administered as a 24-h continuous intravenous infusion. Forty-eight hours after completing paclitaxel, rhG-CSF (5 microg/kg) was initiated and continued until completion of PBSC collection. Leukapheresis was initiated once the white blood cell count reached 1.0 x 10(9)/L. Each collection was evaluated for the numbers of mononuclear cells (MNC) and CD34(+) cells. Clonogenic potential was enumerated using colony-forming units-granulocyte-macrophage (CFU-GM) and burst-forming units-erythroid (BFU-E). Patients receiving paclitaxel with rhG-CSF mobilized a large number of mononuclear cells/apheresis (mean, 3.7 x 10(8); range, 3.3-4.1) and CD34(+) cells/apheresis (mean, 7.2 x 10(6); range, 6.1-8.4). The average number of leukophereses needed was 1.8 (mean, range 1.6-2.0). Colony growth was normal with 178.9 x 10(5) and 214.8 x 10(5) colonies counted in CFU-GM and BFU-E assays, respectively. Patients engrafted platelets and neutrophils on day 10 following transplantation. In conclusion, PBSC mobilization with paclitaxel and rhG-CSF results in a large number of mononuclear cells and CD34(+) cells with normal clonogenic potential. The cells engraft normally following high-dose chemotherapy and autologous stem cell transplantation in high-risk breast cancer patients. These results demonstrate that paclitaxel with rhG-CSF is an efficient mobilizing agent in high-risk breast cancer patients.

Use of paclitaxel in patients with pre-existing cardiomyopathy: a review of our experience

Cardiac toxicity is frequently the indication for discontinuation of an anthracycline in patients with tumors which remain anthracycline-sensitive. During the 1990s, the most frequently used second-line agents at the Yale Cancer Center (YCC) were the taxanes. The goal of this retrospective analysis was to determine the effect of paclitaxel on cardiac function in patients with cardiomyopathy. YCC outpatient clinic pharmacy order forms were used to identify all patients who had received paclitaxel between December 1995 and November 1997. The clinic records of those patients with a left ventricular ejection fraction (LVEF) of < or = 50% were reviewed to determine the temporal relation between the decreased LVEF and paclitaxel therapy. In addition, clinic records were examined for evidence of prior doxorubicin therapy and history of prior cardiac disease. Between December 1995 and November 1997, 225 patients were treated with paclitaxel in the YCC outpatient clinic. Nine patients had LVEF < or = 50% (mean 37%) prior to initiation of paclitaxel therapy. Six of these patients had equilibrium radionuclide angiocardiographic (ERNA) scans following completion of paclitaxel. In these 6 patients, the mean change in LVEF was +6% (range -3% to +29%). Four patients had improved LVEF following paclitaxel (mean 11%, range 2% to 29%), while 2 patients experienced a decrease in LVEF following paclitaxel treatment (mean 2.5%). The 3 patients who did not have ERNA scans following paclitaxel therapy had no clinical evidence of congestive heart failure. Our experience confirms the results of prior studies that paclitaxel can be safely administered in patients with underlying cardiac dysfunction.

High-dose chemotherapy for ovarian carcinoma: long-term results from the Solid Tumour Registry of the European Group for Blood and Marrow Transplantation (EBMT)

PURPOSE

to determine the outcome of epithelial ovarian cancer in patients registered with the European Group for Blood and Marrow Transplantation (EBMT).

PATIENTS AND METHODS

A retrospective analysis was performed on 254 patients with advanced or recurrent disease, median age 46 years (14-63) from 39 centres treated between 1982 and 1996. Only 25% of patients were known to have no or microscopic disease after initial surgery; in approximately 20% the disease status was unknown, the remainder had macroscopic disease.

RESULTS

One hundred five patients received high-dose chemotherapy in complete or very good partial remission, twenty-seven in second remission and the remainder in the presence of residual disease. Most received melphalan or carboplatin, or a combination (86%) supported by autologous bone marrow or peripheral blood stem cells. The survival of patients treated in remission was significantly better than in other groups (median 33 vs. 14 months; P = 0.0001). The durability of remission was longer after transplantation in first remission than in second remission (median disease-free survival 18 vs. 9 months; P = 0.005). With a median follow-up of 76 months from diagnosis the median disease-free and overall survival in stage III disease transplanted in remission is 42 and 59 months and for stage IV disease 26 and 40 months.

CONCLUSIONS

High-dose chemotherapy has a potential benefit for patients in remission. The results support the conduct of randomised studies to determine whether there is a real value from this treatment.

Docetaxel-induced mobilization of hematopoietic stem cells in a murine model: kinetics, dose titration, and toxicity

OBJECTIVE

Docetaxel (DXT) is an anticancer agent that has demonstrated therapeutic efficacy against solid tumors, particularly breast cancer. Based on the use of hematopoietic stem cell (HSC) transplantation to restore hematopoietic reconstitution after myeloablative therapy, this study was performed to determine if DXT could mobilize HSCs in vivo.

MATERIALS AND METHODS

C57Bl/6 mice were injected intraperitoneally with varying doses of DXT (equivalent to human doses of 40 to 120 mg/m(2)). Spleens were harvested on days 2, 4, 6, 8, 10, and 12 after DXT administration for recovery of mononuclear cells (MNCs). The number of HSCs present within the MNCs was determined by clonogenic assay for colony-forming units in culture (CFU-C) and by FACS analysis for CD34(+) cells. Peripheral blood samples were obtained at the time of spleen harvest to determine the hematologic profile. Liver and renal function tests were performed to monitor toxicity.

RESULTS

DXT mobilize d HSCs in a dose- and time-dependent manner. When measured by the CFU-C assay, maximal mobilization of HSC (>10-fold increase in control; p<0.01) was observed at a dose of 30 mg/kg (equivalent to human dose of 75 mg/m(2)) on day 7. The number of mobilized HSCs peaked on days 6 to 8 at all doses of DXT tested. There was no evidence of weight loss, liver, or renal toxicity at any of the DXT doses tested.

CONCLUSION

These results indicate that DXT efficiently mobilizes HSCs in a murine model and provide the rationale for similar studies in a clinical trial.

High dose chemotherapy with peripheral blood stem cell transplantation (PBSCT) in ovarian cancer

Ovarian cancer is a very chemosensitive tumor, but survival is poor due to the emergence of drug resistance. It may be possible to overcome resistance by using high dose chemotherapy supported by peripheral blood stem cell transplantation. A review of retrospective studies of dose-intensity and phase I/II high dose chemotherapy trials, and an analysis of the EBMT registry data is used as evidence to support the case for dose-intensification in ovarian cancer. As a result of this analysis there are now prospective randomized trials of high dose chemotherapy in ovarian cancer.

[Role of high-dose chemotherapy in hematology and internal medicine/ oncology]

BACKGROUND

High-dose chemotherapy (HDCT) with stem cell rescue is increasingly being used as a salvage or consolidation therapy for patients with a variety of malignant diseases. The authors give an overview of the current role of HDCT in lympho-hematopoietic malignancies and solid tumors.

METHODS

The use of allogenic or autologous hematopoietic stem cells allows an increase of the dose of chemotherapeutic drugs by a factor of between 4- and 30-fold compared to conventional chemotherapy protocols. In recent years mobilized peripheral blood stem cells (PBSC) have largely replaced the use of autologous bone marrow due to more rapid hematopoietic reconstitution and are increasingly used in the allogenic setting. This article reviews the data of high-dose chemotherapy in non-Hodgkin's lymphoma, Hodgkin's lymphoma, multiple myeloma, acute leukemias, chronic myelogenous leukemia, chronic lymphatic leukemia, myelodysplastic syndrome, breast cancer, ovarian cancer, germ cell cancer, and lung cancer. Current clinical trials further evaluating the role of HDCT are described.

RESULTS

Data on results of HDCT are available for a variety of malignancies showing the feasibility and efficacy of the procedure with tolerable toxicity. Although numerous clinical trials of HDCT have been performed, only few randomized trials have demonstrated that such strategies are statistically significantly better than conventional forms of therapy.

CONCLUSION

HDCT has been shown to be useful in the treatment of certain patients with lymphomas, leukemias, myeloma, breast cancer, and testicular cancer. Most of these findings still have to be confirmed by randomized clinical trials. Therefore, HDCT should only be given in controlled studies and at suitable centers.

Factors influencing mobilization and engraftment in patients with metastatic breast cancer undergoing PBSC transplantation

Factors influencing mobilization and engraftment of PBSC were analyzed in 38 patients with metastatic breast cancer who were undergoing PBSC transplantation. None of these patients had had previous chemotherapy for metastatic disease. PBSC were mobilized with cyclophosphamide (CY) and G-CSF (n = 21) or CY and etoposide (CY-etoposide) and G-CSF (n = 17). All received cyclophosphamide 6000 mg/m2, thiotepa 500 mg/m2, and carboplatin 800 mg/m2 (CTCb) as preparative regimen. PBSC infusion was followed by G-CSF at 5 microg/kg in 30 patients or 10 microg/kg in 8 patients. A median number of 27 x 10(6) CD34+ cells/kg was obtained with a median of four aphereses. Previous chemotherapy, radiation therapy, marrow disease, time from previous chemotherapy to mobilization, and type of mobilization regimen did not have a statistically significant effect on collection efficiency (CE). CE was defined as the total number of CD34+ collected/number of collections. Engraftment was rapid, with patients reaching a neutrophil count of 0.5 x 10(9)/L a median of 9 days (range 7-23) and a platelet count of 20 x 10(9)/L a median of 12 days (range 8-28) after transplantation. Shorter times to platelet recovery were associated with a higher number of CD34+ cells infused (p = 0.012), CY mobilization (p = 0.033), and a lower number of prior chemotherapy cycles (p = 0.022). When the number of CD34+ cells was included in the proportional hazard model, no other variables were found to be significant predictors of platelet engraftment. Time to neutrophil recovery was negatively associated with the dose of G-CSF used after transplantation (p = 0.036) CD34 cell dose is an important predictor of engraftment kinetics. A posttransplant dose of G-CSF improves neutrophil recovery. For patients with metastatic breast cancer and no previous chemotherapy for metastatic disease, we have no evidence for a difference between CY and CY-Etoposide as the mobilization regimen.

Paclitaxel vs cyclophosphamide in peripheral blood stem cell mobilization: comparative studies in a murine model

Paclitaxel is a promising drug for the treatment of breast and ovarian cancer. It also may play a role in mobilization of peripheral blood stem cells (PBSC), as an alternative to cyclophosphamide (Cy). We investigated the PBSC-mobilizing potential of paclitaxel compared to Cy in a murine model. C57B1/6 mice were primed with intraperitoneal injections of Cy (200 mg/kg) or paclitaxel (60 mg/kg) and were sacrificed 4, 6, 8, or 10 days later. Spleens were harvested and processed to obtain low-density mononuclear cells that were used as PBSC. The number of hematopoietic progenitors (CFU-C) on day 4 was significantly higher in the paclitaxel group when compared to mice receiving Cy (72.0 +/- 1.8 vs 9.8 +/- 2.8, p < 0.001). By day 6, CFU-C became significantly higher in the Cy-treated group compared to the paclitaxel-treated group (195.6 +/- 31.9 vs 95.8 +/- 20.7, p < 0.05) and this trend was maintained. However, the total number of CFU-C recovered per spleen was greater in the paclitaxel-treated group (1.27 x 10(5) +/- 0.53 x 10(5) vs 1.06 x 10(5) +/- 0.36 x 10(5), NS). In contrast to paclitaxel, mobilization with Cy was associated with marked perturbation in the proportion of lymphoid cell subsets in the PBSC population along with functional impairment of lymphocytes. After 24 hours of in vitro IL-2 activation, the cytotoxic effector cell function of the Cy-mobilized PBSC population was lower than that of paclitaxel-mobilized cells when tested against three tumor cell lines (B16, melanoma; C1498, AML; and Yak-1, lymphoma). These results indicate that paclitaxel is an efficient mobilizer of PBSC, leading to early (day 4 to 6) mobilization of PBSC when compared to Cy (day 6 to 8). In addition, paclitaxel was associated with less perturbation of phenotypic and functional characteristics of cells contained within the mobilized PBSC population.

Paclitaxel plus high-dose cyclophosphamide with G-CSF support in patients with relapsed and refractory aggressive non-Hodgkin's lymphoma

Based on the single-agent activity of both paclitaxel and cyclophosphamide in the treatment of non-Hodgkin's lymphoma (NHL), we conducted a phase II study to evaluate the efficacy of the combination of the two drugs in patients with refractory and relapsed aggressive NHL. All patients received 900 mg/m2 bolus of cyclophosphamide intravenously daily for 3 consecutive days with a concurrent infusion of 150 mg/m2 of paclitaxel over 72 h (50 mg/m2/d). 24 h after the completion of chemotherapy, patients received subcutaneous injections of 5 microg/kg of granulocyte-colony stimulating factor (G-CSF) daily until white cell count recovery. Treatment was repeated every 3 weeks. Patients who had at least a partial response (PR) after two courses continued to receive a maximum of four courses. Patients with responding disease were allowed to undergo high-dose chemotherapy followed by stem-cell/bone marrow transplantation if they were eligible. Of the 77 patients who were eligible for the study, 74 (96%) were evaluable for toxicity and treatment response. The overall response rate was 45% (95% CI 33-57%). Patients who received treatment after their disease relapsed from a complete response (CR) had an 81% response rate (38% CRs), whereas those with primary refractory disease had a 22% response rate. Toxicities of > grade 2 included alopecia (100%) and stomatitis (25%). Neutropenic fever of grade > 2 occurred after 18% of the courses, and platelet count of < or = 20 x 10(9)/l developed after 20% of the courses. Thus, the combination of paclitaxel plus high-dose cyclophosphamide is an effective new regimen in the treatment of refractory and relapsed NHL.

Optimising treatment outcomes: a review of current management strategies in first-line chemotherapy of metastatic breast cancer

Metastatic breast cancer remains an essentially incurable disease and chemotherapy, despite producing frequent and clinically useful responses, has had a disappointing impact on survival. Several highly promising lines of clinical research with new agents, combinations and dosages may yet produce an improved outcome. Of the new drugs that have been studied, the taxoids, docetaxel and paclitaxel appear to be the most active agents yet discovered in this setting; navelbine is also active. Investigations of high-dose chemotherapy have produced the highest rates of complete response achieved in patients with this condition. The results of recent randomised trials confirm the high activity of this modality and also suggest a survival advantage compared with more traditionally dosed treatment. Active research into biological therapy is also under way and vaccines, antibodies and inhibitors of growth factors are all being evaluated.

Dose-finding study of paclitaxel and cyclophosphamide in advanced breast cancer

BACKGROUND

The toxicity profile of prolonged infusions of paclitaxel in combination with cyclophosphamide in metastatic breast cancer has already been defined. The objective of this dose-finding study was to determine the maximum tolerable doses (MTDs) of shorter (three-hour) infusions of paclitaxel in combination with i.v. bolus cyclophosphamide in patients who had previously received a maximum of one chemotherapy for advanced breast carcinoma. The MTD of the same regimen with granulocyte colony-stimulating factor (G-CSF) support was then established.

PATIENTS AND METHODS

Eighty women with metastatic breast cancer received a total of 352 fully evaluable courses of therapy. The starting doses were paclitaxel 135 mg/m2 and cyclophosphamide 750 mg/m2 given every three weeks. At least three patients were treated at each dose level and if there were dose-limiting toxic effects during the first cycles three additional patients were entered. G-CSF support (5 micrograms/kg s.c.) was added to the second cycle if specific dose-limiting toxicities had occurred during the first cycle. The MTD was defined as the dose level at which more than two of six patients presented dose-limiting toxicities during the first cycle.

RESULT

Febrile neutropenia (n = 4) and severe thrombocytopenia (n = 1) defined the MTDs of paclitaxel as 200 mg/ m2 and of cyclophosphamide as 2,000 mg/m2 with or without G-CSF in patients with and, respectively, without prior chemotherapy for advanced disease. Non-hematologic toxicity was moderate. Recommended doses were 200 mg/m2 of paclitaxel and 1,750 mg/m2 of cyclophosphamide with or without G-CSF in patients with and, respectively, without prior chemotherapy. The overall response rate was 25% and 50%, respectively, in patients with and without prior chemotherapy for metastatic disease. Complete remissions (9%) were reported only in patients without prior chemotherapy; antitumour activity in women with anthracycline-resistant disease, with an 8% response rate (95% CI: 1%-26%), was poor.

CONCLUSIONS

Paclitaxel at 200 mg/m2 and cyclophosphamide at 1,750 mg/m2 can be safely administered every three weeks to women with advanced breast cancer. The moderate antitumour activity observed with the schedule tested argues against its use as initial therapy for advanced breast cancer.

Collection of circulating progenitor cells after epirubicin, paclitaxel and filgrastim in patients with metastatic breast cancer

The efficacy of high-dose chemotherapy (HDC) and circulating progenitor cell (CPC) transplantation in metastatic breast cancer (MBC) relies mainly on giving this treatment after a response to conventional induction chemotherapy has been achieved. For this reason an optimal mobilization regimen should be therapeutically effective while minimizing the number of leucaphereses required to support the myeloablative therapy. The combination of an anthracycline and paclitaxel in chemotherapy-untreated MBC has produced impressive response rates. We evaluated the CPC-mobilizing capacity of the combination epirubicin (90 mg m(-2)) and paclitaxel (135 mg m(-2)) followed by filgrastim (5 microg kg(-1) day(-1)) starting 48 h after chemotherapy administration in ten patients with MBC who were eligible for an HDC and CPC transplantation programme. Leucaphereses were performed by processing at least two blood volumes per procedure at recovery from neutrophil nadir when CD34+ cells in the peripheral blood exceeded 20 microl(-1). In most patients (six out of 10) more than 2.5 x 10(6) CD34+ cells kg(-1), a threshold considered to be sufficient for haematopoietic reconstitution, were collected with a single apheresis. In the remaining four patients an additional procedure, performed the following day, was enough to reach the required number of progenitors. These data suggest that the epirubicin-paclitaxel combination, besides being a very active regimen in MBC, is effective in releasing large amounts of progenitor cells into circulation.

Tandem high-dose chemotherapy with ifosfamide, carboplatin, and teniposide with autologous bone marrow transplantation for the treatment of poor prognosis common epithelial ovarian carcinoma

BACKGROUND

A phase I or II trial was conducted to assess the toxicity and the efficacy of a tandem high dose chemotherapy combining ifosfamide, carboplatin, and teniposide in patients with poor prognosis ovarian carcinoma.

METHODS

Thirty-seven patients were scheduled to receive tandem high dose therapy combining ifosfamide 7500 to 11250 mg/m2, carboplatin 875 ot 1000 mg/m2 and teniposide 750 to 1000 mg/m2, followed by autologous bone marrow transplantation (ABMT). Eight patients were refractory to the platin-based regimen, 7 were treated in chemosensitive relapse, and 22 in partial or complete response (PR/CR) were treated. Sixty-six cycles were administered. Sixteen patients were evaluated for response.

RESULTS

The overall response rate was 56% (CR rate: 12%). Toxic effects consisted of mainly renal toxicity, esophagitis, and enterocolitis. Three patients died of therapy-related complications. Since the time of ABMT, the median overall survival (OS) duration of the whole population was 18 months and the survival rate was 14% at 60 months. For the 22 patients treated after PR or CR, the median OS duration was 24 months and the survival rate was 32% at 60 months. Tandem high dose therapy with ABMT was unable to circumvent resistance to conventional chemotherapy or to prolong the duration of survival for patients treated in chemosensitive relapse. For patients treated after CR or PR, the survival results were similar to that achieved with conventional therapy.

CONCLUSIONS

Prospective, randomized studies, including patients only after CR or with minimal residual disease, are urgently required to evaluate the activity of high dose therapy in the treatment of advanced ovarian carcinoma.

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

Since 1981, over 300 patients reported with advanced or refractory ovarian cancer have been treated with high-dose chemotherapy supported by autologous bone marrow or peripheral blood stem cell transplantation. Partial or complete clinical response has been reported in 54-100% of the cases, but the median duration of the response in the majority of patients has been only a few months. It is obvious from the available data that high-dose regimens supported by autologous stem cell transplantation (ASCT) are not capable of inducing long-term survival in patients with heavy tumour burden or chemoresistant ovarian cancer. Recent reports on nearly 100 patients have described results of the use of high-dose chemotherapy as first-line treatment for patients with optimally debulked disease or negative second-look laparotomy. Response rates and survival have been better when compared to historical controls, but the efficacy of this treatment modality in inducing durable remission has not been tested in randomized trials. Most of the ongoing trials presented briefly in this review have been designed to evaluate the potential of high-dose therapy as first-line treatment in preventing the development of resistant tumour clones and recurrence. The role of sequential high-dose chemotherapy with ASCT as a part of primary treatment or as salvage therapy for chemosensitive recurrent disease is also under investigation.

Incidence and prevention of nonhaematological toxicity of high-dose chemotherapy

The introduction of the haematopoietic growth factors (HGFs), together with the evolution of techniques to harvest haematopoietic stem cells from the peripheral blood, have greatly facilitated the use of high-dose chemotherapy (HDC). While haematological toxicity of HDC is no longer dose-limiting, damage to other tissues has become more pronounced. In fact, nonhaematological toxicity (NHTOX) is now often dose-limiting in HDC regimens. NHTOX associated with HDC regimens depends on the type and dose of the drugs used, the physical condition and the characteristics of the patients treated and the given comedication. We describe the most important toxic effects of commonly used HDC programmes, such as nausea, vomiting, and mucositis, neutropaenic fever and sepsis, various major organ toxicities, catheter-associated problems and long-term complications. In addition, we discuss the possibilities of preventing these side-effects and what action to take if they occur.

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

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