Cyclophosphamide, Thiotepa, And Carboplatin Research Articles

Relations between polymorphisms in drug-metabolising enzymes and toxicity of chemotherapy with cyclophosphamide, thiotepa and carboplatin

High-dose chemotherapy with cyclophosphamide, thiotepa and carboplatin (CTC) has been developed as a possible curative treatment modality in several solid tumours. However, a large interindividual variability in toxicity is encountered in high-dose chemotherapy. A priori identification of patients at risk for toxicity could be an attractive prospect. Genotyping of genes encoding drug-metabolising enzymes might provide such a tool. We assessed 16 selected polymorphisms in nine genes (CYP2B6, CYP2C9, CYP2C19, CYP3A4, CYP3A5, GSTA1, GSTP1, ALDH1A1 and ALDH3A1) of putative relevance in CTC metabolism using polymerase chain reaction and DNA sequencing in 113 patients who were treated with high-dose chemotherapy regimens based on CTC. Patients heterozygous for the ALDH3A1*2 allele (allelic frequency 21.2%) had an increased risk of haemorrhagic cystitis when compared with patients with wild-type alleles [5/38 vs. 1/70; odds ratio (OR): 11.95, 95% confidence interval (CI): 1.18-120.56; P=0.04]. Furthermore, patients heterozygous for the ALDH1A1*2 allele (allelic frequency 5.8%) had an increased risk of liver toxicity when compared with patients with wild-type alleles (6/13 vs. 19/99; OR: 5.13, 95% CI: 1.30-20.30; P=0.02). No other relations reached significance. Patients heterozygous for the ALDH3A1*2 and ALDH1A1*2 allele have an increased risk of haemorrhagic cystitis and liver toxicity, respectively, compared with patients with wild-type alleles when treated with a high-dose chemotherapy combination of CTC. Pharmacogenetic approaches can identify patients who are at risk of experiencing toxic side effects in high-dose chemotherapy.

Topoisomerase IIa gene amplification predicts favorable outcome of tailored and dose-escalated anthracycline-based adjuvant chemotherapy in HER-2 positive breast cancer. Results from the randomized trial SBG 9401

9518 Background: Amplification of the HER-2/neu and topoisomerase IIα (TOP2A) genes has been linked to the effects of anthracyclines. Their role in predicting outcome of anthracycline-based adjuvant chemotherapy for breast cancer patients has remained controversial. Methods: High-risk breast cancer patients (with 5 or more positive axillary lymph nodes) were included in the present substudy of the SBG 9401 study, comparing an epirubicin-based regimen (9 courses of tailored and dose-escalated 5-fluorouracil, epirubicin and cyclophosphamide; FEC) with 3–4 courses of standard FEC followed by marrow-supported high-dose chemotherapy with cyclophosphamide, thiotepa and carboplatin (CTCb). Amplification of HER-2/neu and TOP2A were determined retrospectively on paraffin-embedded tumor tissue sections by chromogenic in situ hybridization (CISH), tissue samples were available from 396/525 (75%) patients. The primary end-point was time to recurrence of breast cancer. Results: HER-2/neu amplification, present in 32.7% of the tumors, was a strong prognostic factor for short relapse-free survival (p=0.0034), but did not predict treatment outcome in either treatment group separately. TOP2A gene amplification, present in 37% of HER-2/neu positive tumors, was associated with a statistically significantly better relapse-free survival than TOP2A non-amplified tumors in patients treated with tailored and dose-escalated FEC (HR=0.44, p=0.049). There was no such correlation seen in patients treated with standard FEC followed by the marrow-supported CTCb regimen (HR=0.95; p=0.87). TOP2A amplification was not associated with tumor size, lymph node status or hormone receptor status. Conclusions: Topoisomerase IIa gene amplification defines a subgroup of HER-2 amplified tumors patients who benefit from the tailored and dose-escalated FEC regimen, indicating that epirubicin should be given with sufficient dose intensity and total dose for a better outcome for this small subgroup. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Bristol-Myers Squibb, Roche Finland Aventis, Bristol-Myers Squibb Hoffmann-La Roche Aventis, Lilly Oncology, Pierre Fabre, Roche

Aprepitant inhibits cyclophosphamide bioactivation and thiotepa metabolism

Patients receiving the highly emetogenic high-dose chemotherapy regimen with cyclophosphamide, thiotepa and carboplatin (CTC) may benefit from the neurokin-1 receptor antagonist aprepitant in addition to standard anti-emetic therapy. As aprepitant has been shown to be a moderate inhibitor of the cytochrome P450 (CYP) 3A4 isoenzyme, its effect on the pharmacokinetics and metabolism of cyclophosphamide and thiotepa was evaluated. Moreover, preliminary results on the clinical efficacy of aprepitant in the CTC regimen are reported. Six patients were enrolled in a protocol that employed a 4-day course of CTC high-dose chemotherapy with cyclophosphamide (1,500 mg/m2/day), thiotepa (120 mg/m2/day) and carboplatin (AUC 5 mg min/ml/day). Two patients received the tCTC protocol, which comprises two-third of the dose of CTC. In addition to standard anti-emetic therapy, the patients received aprepitant from one day before the start of their course until 3 days after chemotherapy. Blood samples were collected on days one and three of the course and analyzed for cyclophosphamide and its activated metabolite 4-hydroxycyclophosphamide, thiotepa and its main active metabolite tepa. The influence of aprepitant on the pharmacokinetics of cyclophosphamide and thiotepa was analyzed using a population pharmacokinetic analysis including a reference population of 49 patients receiving the same chemotherapy regimen without aprepitant and sampled under the same conditions. The frequency of nausea and vomiting in the six patients receiving CTC was compared with those of the last 22 consecutive patients receiving CTC chemotherapy without aprepitant. Inhibitory activity of aprepitant on cyclophosphamide and thiotepa metabolism was also tested in human liver microsomes. In our patient population, the rate of autoinduction of cyclophosphamide (P=0.040) and the formation clearance of tepa (P<0.001) were reduced with 23% and 33% when aprepitant was co-administered, respectively. Exposures to the active metabolite 4-hydroxycyclophosphamide and tepa were therefore reduced (5% and 20%, respectively) in the presence of aprepitant. In human liver microsomes, the 50% inhibitory concentrations (IC50) of aprepitant for inhibition of cyclophosphamide (IC50=1.3 microg/ml) and thiotepa (IC50=0.27 microg/ml) metabolism were within the therapeutic range. Patients receiving aprepitant experienced less frequently CINV both during and after the CTC course compared with the reference population (nausea 3.7 days vs. 5.8 days, P=0.052; vomiting 0.5 days vs. 4.8 days, P<0.001). Aprepitant inhibited both cyclophosphamide and thiotepa metabolism, most probably due to inhibition of the CYP 3A4 and/or 2B6 isoenzymes. The effects of this interaction are, however, small compared to the total variability. Addition of aprepitant may provide superior protection against vomiting in patients receiving the highly emetogenic high-dose CTC chemotherapy.

High-Dose Chemotherapy of Cyclophosphamide, Thiotepa and Carboplatin (CTCb) followed by Autologous Stem-Cell Transplantation as a Consolidation for Breast Cancer Patients with 10 or more Positive Lymph Nodes: a 5-Year follow-Up Results

The benefit of consolidation high-dose chemotherapy (HDC) for high-risk primary breast cancer is controversial. We evaluated the efficacy and safety of consolidation HDC with cyclophosphamide, thiotepa and carboplatin (CTCb) followed by autologous stem-cell transplantation (ASCT) in resected breast cancer patients with 10 or more positive lymph nodes. Between December 1994 and April 2000, 22 patients were enrolled. All patients received 2 to 6 cycles of adjuvant chemotherapy after surgery for breast cancer. The HDC regimen consisted of cyclophosphamide 1,500 mg/m(2)/day, thiotepa 125 mg/m(2)/day and carboplatin 200 mg/m(2)/day intravenous for 4 consecutive days. With a median follow-up of 58 months, 11 patients recurred and died. The median disease-free survival (DFS) and median overall survival (OS) were 49 and 69 months, respectively. The 5-year DFS and OS rates were 50% and 58%, respectively. The 12 patients with 10 to 18 involved nodes had better 5-year DFS (67%) and OS (75%) than 10 patients with more than 18 involved nodes (30% and 38%, respectively). The most common grade 3 or 4 nonhematologic toxicity was diarrhea, which occurred in 5 patients (23%). No treatment-related death was observed. Consolidation HDC with CTCb followed by ASCT for resected breast cancer with more than 10 positive nodes had an acceptable toxicity but does not show promising survival.

High-dose chemotherapy of cyclophosphamide, thiotepa, and carboplatin (CTCb) followed by autologous stem-cell transplantation for metastatic breast cancer patients: a 6-year follow-up result.

The benefit of high-dose chemotherapy (HDC) for metastatic breast cancer (MBC) is controversial. We evaluated the efficacy and safety of HDC with cyclophosphamide, thiotepa, and carboplatin (CTCb) followed by autologous stem-cell transplantation (ASCT) for MBC patients. From September 1994 to December 1999, 23 MBC patients were enrolled. All the patients received 2 to 10 cycles of induction chemotherapy. Before transplantation, 12 patients were in complete response (CR), nine were in partial response (PR), and two had progressive disease (PD). The HDC regimen consisted of cyclophosphamide 1,500 mg/m(2)/day, thiotepa 125 mg/m(2)/day and carboplatin 200 mg/m(2)/day intravenously for 4 consecutive days. After ASCT, 13 patients (56%) had a CR, five (22%) had a PR, three (13%) had no change, while two (9%) showed a PD. Seventeen patients relapsed or progressed during the median follow-up of 78 months. The median progression-free survival (PFS) time was 11 months and the median overall survival (OS) time was 23 months. The 5-year PFS and OS rates were 22% and 25%, respectively. On the multivariate analyses, less than 4 involved lymph nodes was predictive of a better PFS and OS. HDC with CTCb for MBC has acceptable toxicity; however, this treatment does not show a survival benefit.

Possible benefits of high-dose chemotherapy and autologous stem cell transplantation for adults with recurrent medulloblastoma.

In an attempt to improve the dismal prognosis of adults with recurrent medulloblastoma, six patients were treated with aggressive salvage therapy including high-dose chemotherapy (HDCT) and autologous stem cell transplantation (ASCT). At relapse, all patients underwent surgical debulking followed by HDCT/ASCT and then radiotherapy when possible. The treatment plan included two cycles of HDCT/ASCT; first with cyclophosphamide, etoposide and carboplatin (CECb) and then 2 months later with cyclophosphamide and thiotepa (CT). Three of the six patients received the planned therapy. One patient experienced severe toxicity requiring life-sustaining therapy. This patient developed multi-organ dysfunction including multiple enhancing lesions in both cerebral hemispheres that slowly resolved over several months. Two other patients did not mobilize sufficient stem cells for two ASCT procedures. They received one ASCT conditioned with cyclophosphamide, thiotepa and carboplatin (CTCb). Three of six patients had a complete response (CR); the other three had a partial response (PR). Following the first ASCT, median duration of response was 13.5 months (range 9-29 months) and median survival was 21.5 months (range 12-42 months). There was no treatment-related mortality. We conclude that HDCT/ASCT with CECb-CT or CTCb is active against recurrent medulloblastoma in adults and may be associated with prolonged remissions. Multiple enhancing cerebral lesions on brain MRI early post-HDCT/ASCT may be a consequence of the treatment rather than metastatic disease.

Relationship between irreversible alopecia and exposure to cyclophosphamide, thiotepa and carboplatin (CTC) in high-dose chemotherapy.

Reversible alopecia is a commonly observed, important and distressing complication of chemotherapy. Permanent alopecia, however, is rare after standard-dose therapy, but has occasionally been observed after high-dose chemotherapy with cyclophosphamide, thiotepa and carboplatin (CTC). We evaluated the relationships between total exposure to these three compounds and their different metabolites in the high-dose CTC regimen, and the subsequent development of irreversible alopecia. Twenty-four patients received two or three courses of high-dose CTC, each followed by peripheral blood progenitor cell transplantation. Plasma levels of cyclophosphamide, its active metabolite 4-hydroxycyclophosphamide, thiotepa, its active metabolite tepa, and carboplatin were determined, and the area-under-the-plasma concentration-versus-time curves (AUC) of the compounds were calculated. Eight of the 24 patients included in the study developed permanent alopecia, while seven had normal hair regrowth and nine patients developed incomplete and/or thin hair regrowth. The carboplatin AUC and the summed AUC of thiotepa and tepa were both significantly associated with increasing irreversibility of hair loss. These results suggest that high exposure to carboplatin and the sum of the thiotepa and tepa exposure may lead to the development of permanent alopecia. This knowledge could guide therapeutic drug monitoring in order to prevent the occurrence of permanent alopecia and thereby improve the patients' quality of life.

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

Chemotherapy drug distribution varies greatly among individual patients. Therefore, we developed an individualised fluorouracil, epirubicin, cyclophosphamide (FEC) regimen to improve outcomes in patients with high-risk early breast cancer. We then did a randomised trial to compare this individually tailored FEC regimen with conventional adjuvant chemotherapy followed by consolidation with high-dose chemotherapy with stem-cell support. 525 women younger than 60 years of age with high-risk primary breast cancer were randomised after surgery to receive nine cycles of tailored FEC to haematological equitoxicity with granulocyte colony-stimulating factor (G-CSF) support (n=251), or three cycles of FEC at standard doses followed by high-dose chemotherapy with cyclophosphamide, thiotepa, and carboplatin (CTCb), and peripheral-blood stem-cell or bone-marrow support (n=274). Both groups received locoregional radiation therapy and tamoxifen for 5 years. The primary outcome measure was relapse-free survival, and analysis was by intention to treat. At a median follow-up of 34.3 months, there were 81 breast-cancer relapses in the tailored FEC group versus 113 in the CTCb group (double triangular method p=0.04). 60 deaths occurred in the tailored FEC group and 82 in the CTCb group (log-rank p=0.12). Patients in the CTCb group experienced more grade 3 or 4 acute toxicity compared with the tailored FEC group (p<0.0001). Two treatment-related deaths (0.7%) occurred in the CTCb group. Six patients in the tailored FEC group developed acute myeloid leukaemia and three developed myelodysplastic syndrome. Tailored FEC with G-CSF support resulted in a significantly improved relapse-free survival and fewer grade 3 and 4 toxicities compared with marrow-supported high-dose chemotherapy with CTCb as adjuvant therapy of women with high-risk primary breast cancer.

Adjuvant Dose-Intense Chemotherapy With Peripheral Blood Stem Cell Support in Stage II-III Breast Cancer With Five to Nine Involved Axillary Lymph Nodes

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

977 - A randomized single-institution study of high-dose chemotherapy with cyclophosphamide, thiotepa and carboplatin (CTC) in apical node-positive breast cancer

977 - A randomized single-institution study of high-dose chemotherapy with cyclophosphamide, thiotepa and carboplatin (CTC) in apical node-positive breast cancer

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

As an alternative to single-cycle cyclophosphamide, thiotepa, and carboplatin (CTCb) intensification, we evaluated the feasibility of administering one-quarter dose CTCb for four cycles with peripheral-blood progenitor-cell (PBPC) and filgrastim (granulocyte colony-stimulating factor [G-CSF]) in advanced-stage breast cancer patients. From June 1992 to August 1993, 20 stage IIIB (n = 7) and IV (n = 13) breast cancer patients received 78 cycles of induction with doxorubicin 90 mg/m2 by intravenous (IV) bolus with G-CSF 5 microg/kg/d by subcutaneous injection (SC) repeated every 14 to 21 days for four cycles. PBPC were collected by 2-hour single-blood volume leukapheresis on 2 consecutive days at the time of hematologic recovery from each cycle of doxorubicin. Eighteen patients received 61 cycles of intensification with cyclophosphamide 1,500 mg/m2, thiotepa 125 mg/m2, and carboplatin 200 mg/m2 by IV continuous infusion with G-CSF 10 microg/kg/d SC and PBPC support repeated every 21 to 42 days for four cycles. Twelve of 20 patients (60%) completed all four planned cycles of doxorubicin induction followed by four cycles of one-quarter dose CTCb intensification. Statistically significantly decreases in the yield of mononuclear cells (MNC) (median slope per day, -0.032; P = .03), granulocyte-macrophage colony-forming unit (CFU-GM) (median slope per day, -0.57; P = .0008), and burst-forming unit-erythroid (BFU-E) (median slope per day, -1.18; P = .006) were observed over the course of the eight leukaphereses. Of 18 patients who began CTCb, 12 (67%) completed four cycles. Six patients were removed from study during intensification: two for progressive disease (PD), one refused further treatment, and three for dose-limiting hematologic toxicity. A fourth patient fulfilled the criteria for dose-limiting hematologic toxicity after cycle 4. The toxicity of the multiple cycle CTCb intensification regimen consisted of grade IV leukopenia, grade IV thrombocytopenia, and febrile neutropenia in 100%, 100%, and 26% of cycles, respectively. The median duration of each CTCb cycle was 24 days (range, 18 to 63), and the median duration of an absolute neutrophil count (ANC) < or = 500/microL and platelet count < or = 20,000/microL during each cycle was 6 days (range, 2 to 15) and 4 days (range, 0 to 38), respectively. It is feasible to administer repetitive cycles of one-quarter dose CTCb intensification with PBPC and G-CSF. Additional studies are required to determine whether multiple cycles of CTCb intensification might offer a therapeutic advantage over a single high-dose cycle.

High-Dose Chemotherapy with Autologous Stem Cell Support for Breast Cancer: A Review of the Dana-Farber Cancer Institute/Beth Israel Hospital Experience

The overall median survival of women with advanced or high-risk primary breast cancer has not changed with conventional chemotherapy. Regimens employing high-dose chemotherapy with autologous stem cell support (ABMT) have been developed with the hope of optimizing tumor response and increasing survival. Early phase I studies in women with advanced refractory disease achieved high response rates of short duration. Second generation studies combined an induction phase followed by one high-dose intensification at time of maximum tumor response. The Dana-Farber Cancer Institute/Beth Israel Hospitals have developed the high-dose intensification regimen of cyclophosphamide, thiotepa, and carboplatin (CTCb) for use in women with metastatic and high-risk stage IIIB/inflammatory breast cancer. To date, approximately 19% of women with metastatic disease remain progression free using this approach, with median length of follow-up approaching 40 months. Although the median duration of follow-up for the stage IIIB women is much shorter (approximately 12 months), greater than 90% of these women are thus far disease free. With the advent of hematologic support, such as blood stem cells and colony-stimulating factors, the morbidity, mortality, and costs associated with this treatment have been substantially reduced, allowing for two or more cycles of high-dose intensification to be employed, to exploit the potential of dose-intensity to optimize response.

Cyclophosphamide pharmacokinetics: correlation with cardiac toxicity and tumor response.

Cyclophosphamide, which forms the nucleus for virtually all preparative regimens for autologous bone marrow transplantation (ABMT), is an alkylating agent of which cytotoxicity is not directly caused by the parent compound but by its biologically active metabolites. Its nonmyelosuppressive toxicity in the ABMT setting is cardiomyopathy. We attempted to determine any correlation between plasma levels of total cyclophosphamide and the subsequent development of cardiac dysfunction. Analyses of plasma levels and the derivation of plasma concentration-time curves (area under the curve [AUC]) were performed in 19 women with metastatic breast carcinoma, who received a continuous 96-hour infusion of cyclophosphamide, thiotepa, and carboplatin (CTCb) with ABMT. The assay for total cyclophosphamide measures the inactive parent compound; reliable assays of the active metabolites of cyclophosphamide are not yet available. Six of 19 women developed moderate, but transient, congestive heart failure (CHF) as assessed by clinical and radiologic criteria. These patients had a significantly lower AUC of total cyclophosphamide (median, 2,888 mumol/L/h) than patients who did not develop CHF (median, 6,121 mumol/L/h) (P less than .002). Median duration of tumor response in these patients was also more durable; at least 22 months in patients with lower AUCs versus a median of 5.25 months in those with higher AUCs (P = .008). These pharmacokinetic data support the premise that enhancement of cyclophosphamide activation may lead to both greater tumor cytotoxicity and increased but reversible end-organ toxicity. Early analysis of pharmacokinetic data may allow modulation of cyclophosphamide administration in an attempt to enhance therapeutic efficacy.

A phase II study of high-dose cyclophosphamide, thiotepa, and carboplatin with autologous marrow support in women with measurable advanced breast cancer responding to standard-dose therapy.

The study was designed to determine the duration of complete response (CR) for patients with unresectable or metastatic breast cancer treated with high-dose cyclophosphamide, thiotepa, and carboplatin (CTCb) while responding to conventional-dose therapy. Eligibility criteria included histologically documented metastatic or unresectable breast cancer, at least a partial response (PR) to conventional-dose therapy, no prior pelvic radiotherapy, cumulative doxorubicin of less than 500 mg/m3, and physiologic age between 18 and 55 years. Patients with inadequate renal, hepatic, pulmonary, and/or cardiac function or tumor involvement of marrow or CNS were excluded. Cyclophosphamide 6,000 mg/m2, thiotepa 500 mg/m2, and carboplatin 800 mg/m2 were given by continuous infusion over 4 days. After recovery, sites of prior bulk disease were to be radiated or resected if feasible. Of 29 registered patients, one died of toxicity (3%; hemorrhage). CRs and PRs continued a median of 16 and 5 months after transplant, respectively (26 and 9 months from initiation of chemotherapy for metastatic disease). Of 10 patients transplanted in CR, four have not progressed at 17 to 31 months after transplantation (25 to 43 months after beginning standard-dose therapy). One of four patients with uptake on bone scan as their only sites of residual disease before transplant and one of three who converted from PR to CR with transplant have not progressed at 27 and 29 months, respectively, after transplant. CTCb is an intensification regimen with a low mortality that delivers a significantly increased dose of agents with known activity at conventional doses in breast cancer. Although the duration of PR is short as expected, CRs appear to be durable.

A phase I-II study of cyclophosphamide, thiotepa, and carboplatin with autologous bone marrow transplantation in solid tumor patients.

The principles of dose-response and combination chemotherapy were basic to the design of the initial curative standard-dose treatment regimens for leukemias, lymphomas, and testis cancer. Agents were selected with different dose-limiting toxicities, resulting in subadditive toxicity in combination. A fourth principle in the design of curative regimens was to combine agents with different mechanisms of action to avoid cross-resistance. Based on these principles, combinations of the highest tolerated doses of active noncross-resistant agents are required to decrease the emergence of drug resistance and achieve optimum cytotoxicity. Hematopoietic stem-cell support provides a mechanism for significantly increasing the doses of active agents, a strategy that has resulted in the cure of 10% to 50% of selected patients with lymphoma who could not be cured with standard-dose therapy. The lack of sufficiently effective cytoreductive conditioning regimens remains the major impediment to improving the high-dose therapy of patients with solid tumors. In this study, 27 patients with solid tumors were treated with a combination of cyclophosphamide, thiotepa, and carboplatin (CTCb) in a phase I-II study. Severe mucositis and neurotoxicity were dose-limiting. The maximum-tolerated dose (MTD) of the combination was 6.0 g/m2 of cyclophosphamide, 500 mg/m2 of thiotepa, and 800 mg/m2 of carboplatin. There were two deaths (7%) of sepsis, and an overall response rate of 72% in refractory tumors (81% in breast cancer). CTCb is a combination with low morbidity and high cytoreductive efficacy designed to exploit the principles of curative cancer chemotherapy.