A Feasibility Study of Multiple Cycle Therapy with Melphalan, Thiotepa

Vol. 5, 3411–3418, November 1999 Clinical Cancer Research 3411

A Feasibility Study of Multiple Cycle Therapy with Melphalan, Thiotepa, and Paclitaxel followed by Mitoxantrone, Thiotepa, and Paclitaxel with Autologous Hematopoietic Cell Support for Metastatic Breast Cancer

Wendy W. Hu,1 Gwynn D. Long,2 PBPCs were performed on an outpatient basis. The first Keith E. Stockerl-Goldstein, Laura J. Johnston, seven patients were randomized to receive alternate cycle .G-CSF or placebo on day ؉1 of each cycle Nelson J. Chao,2 Robert S. Negrin, and Including the initial pulse of cyclophosphamide, 67 Karl G. Blume (84%) of a planned 80 total courses of chemotherapy were Division of Bone Marrow Transplantation, Department of Medicine, delivered. Of the planned 64 cycles of high-dose combination Stanford University Medical Center, Stanford, California 94305 chemotherapy, 52 cycles (81%) were delivered. Treatment was discontinued for progressive disease (one patient) or ABSTRACT morbidity (five patients). Twelve of 16 patients completed at least three cycles of therapy. Nine patients completed all Dose-intensive chemotherapy appears to be important four cycles. One death resulted from fungal sepsis. In 20 in the treatment of patients with recurrent solid tumors. cycles delivered to the first seven patients, day ؉1 G-CSF Expanding upon our prior experience, we report the results versus placebo was administered, with a median WBC re- of our most recent approach to administering dose-intensive in cycle 0.048 ؍ covery of 10 versus 13 days, respectively (P therapy using four cycles of moderately high-dose chemo- 1). The median duration of response was almost 9 months, therapy with hematopoietic cell support for patients with and the median survival was 18 months after therapy. With metastatic breast cancer. This outpatient therapy includes a median follow-up of 1.5 years and longest follow-up of 4.2 high-dose melphalan, thiotepa, and paclitaxel for two cycles years, two patients continue to be without evidence of dis- followed by mitoxantrone, thiotepa, and paclitaxel for two ease. The 3-year event-free survival, freedom from progres- cycles, with each cycle supported with autologous peripheral sion, and overall survival are 19%, 20%, and 31%, respec- blood progenitor cells (PBPCs). tively. Between December 1994 and June 1996, 16 patients This four-cycle regimen of high-dose combination ther- with recurrent or refractory breast cancer were enrolled in apy supported with hematopoietic progenitor cells is feasi- this prospective study. They had received a median of two ble, but it is associated with a range of posttransplant com- previous chemotherapy regimens, with a median of nine plications. The efficacy of such a treatment would have to be prior cycles of chemotherapy. For mobilization of autolo- substantially superior to that of other currently available gous PBPCs, patients received cyclophosphamide, 4 g/m2, therapies, including single autologous transplant proce- followed by granulocyte colony-stimulating factor (G-CSF). dures, to justify the prolonged period of treatment, multiple PBPCs were collected by apheresis. Each day’s collection episodes of pancytopenia, and associated toxicities, including was divided into four equal fractions, and each fraction was infectious risks. G-CSF administration after each PBPC infused after each cycle of combination therapy. Cycles 1 infusion appears to accelerate time to neutrophil recovery and 2 consisted of melphalan, 80 mg/m2, thiotepa, 300 mg/ but does not affect red cell or platelet engraftment. m2, and paclitaxel, 200 mg/m2. Cycles 3 and 4 were com- prised of mitoxantrone, 30 mg/m2, and thiotepa and paclitaxel at the same doses as in the first two cycles. The INTRODUCTION cyclophosphamide infusion was administered in the hospi- Much experience has been gleaned throughout decades of tal, whereas all subsequent infusions of chemotherapy and research into tumor growth kinetics and cytotoxic therapy. The observation of a specific log-kill curve for an individual che- motherapeutic drug led to the development of treatment schemes using combinations of agents, with each one potentially adding to the overall cell kill. Subsequently, the timing and Received 2/01/99; revised 7/21/99; accepted 8/6/99. sequence of chemotherapy, the method of drug delivery, dose The costs of publication of this article were defrayed in part by the escalation, and dose intensity have become important concepts payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to in the treatment of cancer. indicate this fact. Substantial data exist to support the importance of dose 1 To whom requests for reprints should be addressed, at Division of intensity (the amount of drug delivered per unit of time) in the Bone Marrow Transplantation, Stanford University Medical Center, 300 treatment of solid tumors (1–3). However, increasing dose in- Pasteur Drive, H1353, Stanford, CA 94305. Phone: (650) 723-0822; Fax: (650) 725-8950; E-mail: [email protected]. tensity to levels that require cytokine support has not been 2 Present address: Duke University Medical Center, 2400 Pratt Street unequivocally established as more efficacious than standard Suite 100, Box 3961, Durham, NC 27705. dose therapy in prolonging overall survival in the treatment of

Fig. 1 Schematic of chemotherapy administration. Days between administration of cycles were scheduled every 21 days.

metastatic breast cancer (4–9). Proposed reasons for these re- cyclophosphamide followed by G-CSF was used to mobilize sults include variable reporting of actual doses received and autologous PBPCs. Our present report describes this four-cycle insufficient dose escalation to achieve statistically significant regimen and treatment outcomes for women with metastatic improvements in survival. Bezwoda and colleagues (10) at- breast cancer. tempted to administer dose-intensive therapy in their randomized study demonstrating improvement in survival outcomes for patients with newly diagnosed metastatic breast cancer . How- MATERIALS AND METHODS ever, this somewhat controversial study was criticized for its Patient Eligibility. Sixteen patients with recurrent lack of high-dose cyclophosphamide in the standard dose arm, breast cancer were enrolled in this study between January the use of an unusual combination chemotherapy regimen in the 1995 and June 1996. Patient eligibility criteria included the standard dose arm, the unbalanced dispensing of tamoxifen following: age Ͻ65 years, Karnofsky performance status therapy, and the resulting surprisingly poor survivals therein. Ն80%, the absence of central nervous system metastasis, and Although this study suggested that the second course of high- demonstration of adequate organ function and HIV seroneg- dose therapy may have been necessary to achieve the superior ativity. Chemotherapy-responsive disease or minimal tumor results, the impact of this was not ascertained sufficiently. The volume was not criteria for eligibility. The risks and benefits phase III studies that have demonstrated improvement in out- of the therapy were explained to patients at the initial clinic come from high-dose therapy for patients with lymphoma (11) visit and again at enrollment when written consent was and multiple myeloma (12) have administered a peak dose of obtained. The clinical protocol was approved by the Admin- single course myeloablative therapy as consolidation after re- istrative Panel on Human Subjects in Medical Research at sponse to standard dose therapies. The role of sufficiently dose- Stanford University. The study schema is depicted in Fig. 1. intensive multiple-cycle therapy made possible by hematopoi- Patient characteristics are listed in Table 1. Patients were etic progenitor cell support has not yet been fully addressed assessed for toxicity and response after each cycle of high- (13–19), and the development of future clinical studies for this dose therapy. A patient could be taken off the study if she did question may depend upon the results of current randomized not demonstrate continued improvement of disease status studies using single courses of high-dose therapy. with each cycle of therapy based upon investigator discretion We have previously reported a pilot study that described and assessment of clinical status. administration of dose- intensive four-cycle therapy with hema- Collection of PBPCs. All patients underwent placement topoietic cell support (20). Patients received repetitive cycles of of a double-lumen tunnelled catheter (12 French Cook, Bloom- high-dose mitoxantrone, thiotepa, and cyclophosphamide. Each ington, IN) before the administration of high-dose cyclophos- cycle was supported with PBPCs3 that had been collected after phamide. Patients received cyclophosphamide at 4 g/m2 i.v. recovery from high-dose etoposide and G-CSF. We subse- over 2 h. They were discharged the following day and treated quently modified the regimen by escalating the doses of MTC with G-CSF (Amgen, Thousand Oaks, CA) at ϳ10 ␮g/kg be- and adding paclitaxel to the regimen (MTTC).4 However, 10 of ginning 24 h after the completion of cyclosphosphamide infu- 18 patients treated with MTTC experienced cyclophosphamide- sion. G-CSF was continued daily until the target number of related toxicity, including hemorrhagic cystitis, interstitial pneu- CD34ϩ cells or alternate target of mononuclear cells was col- monitis, and cardiac dysfunction. lected by apheresis. Prophylactic oral rifampin and ciprofloxa- We attempted to ameliorate the toxicity of MTTC by further modification of the regimen. Cyclophosphamide was cin were begun at the time of discharge and continued until eliminated from the repetitive cycle regimen, and melphalan recovery from neutropenia. The collection of autologous PBPCs (Alkeran) was substituted for mitoxantrone (ATT) in the first by apheresis was initiated after recovery from cyclophospha- Ͼ ␮ two treatment cycles (ATT ϫ2/MTT ϫ2). An initial pulse of mide the day after the leukocyte count was 1,000/ l and was continued daily until the target goal of 10 ϫ 106 CD34ϩ cells/kg or an alternate goal of 1 ϫ 109 mononuclear cells/kg was collected. Cells expressing the surface marker CD34 were 3 The abbreviations used are: PBPC, peripheral blood progenitor cell; identified by indirect immunofluorescence with the monoclonal G-CSF, granulocyte colony-stimulating factor; ANC, absolute neutro- antibody HPCA-2 (Becton Dickinson, Mountain View, CA) phil count; CR, complete response; VGPR, very good partial response; conjugated to phycoerythin using a FAC-STAR cell sorter (Bec- PR, partial response; SD, stable disease; PD, progressive disease; SPN, ton Dickinson). Bone marrow was not collected from any pa- Stanford patient number; PCP, Pneumocystis carinii pneumonia; ATT, Ͼ ␮ melphalan (Alkeran), thiotepa, paclitaxel (Taxol); MTT, mitroxantrone, tient. Platelet counts were maintained 10,000/ l with irradi- thiotepa, paclitaxel (Taxol). ated (2500 cGy) platelet concentrates. The PBPCs were 4 Unpublished data. processed and cryopreserved as described previously (20).

Chemotherapy Regimen and PBPC Infusion. This schema called for administration of four cycles of high-dose F/U (days) therapy every 21 days on an outpatient basis. After the adequate collection of PBPCs, melphalan at 80 mg/m2 was infused i.v. over 20 min on day Ϫ4. Thiotepa, 300 mg/m2, was then delivered by continuous infusion pump over 48 h from day Ϫ4today Ϫ2. After completion of thiotepa, patients received paclitaxel, 200 mg/m2,over3hondayϪ2. On day 0, one quarter of the cryopreserved autologous PBPCs were thawed and infused. This to HDC Survival

Response therapy was repeated in cycle 2. In cycles 3 and 4, mitoxantrone, 30 mg/m2, and thiotepa were delivered by continuous infusion over 48 h from day Ϫ4todayϪ2. Paclitaxel and PBPCs were cycles

# HDC administered as in the first two cycles. Supportive Care. Patients were evaluated twice daily on an outpatient basis. Each morning, patients presented to the Day

Status Hospital for physician evaluation and infusions of medications at HDC or blood products, if necessary, as determined by the previous evening’s laboratories. In the evening, patients received home care nursing assessment, blood sampling for laboratory analysis, and infusion of medications. Continuous infusion of i.v. fluid containing low-dose heparin (10 units/kg/day) was administered by Cadd pump (Sims Deltech, St. Paul, MN) at the start of each chemotherapy and continued until recovery from neutropenia. With the first cycle of therapy, all patients received prophylactic trimethoprim-sulfamethoxazole (160 mg/800 mg IV bid) for 3 days on day Ϫ4todayϪ2. Inhaled pentamidine (300 mg) was substituted if patients were allergic to sulfa antibiotics. Except for the initial patient, all patients received either prophylactic trimethoprim-sulfamethoxazole or pentamidine at the beginning of each cycle. At the time of neutropenia, patients received prophylactic i.v. antibiotics starting with vancomycin (1 g bid). Ceftriaxone (2 g daily) was added for low-grade febrile episodes. Patients were admitted to the hospital when fever was Ͼ38.5°C. Antibiotics were continued until the ANC was Ͼ500/ ␮l. All patients received transfusions of irradiated packed RBCs or platelet concentrates to maintain a hematocrit Ͼ30% and Ͼ ␮ Patient characteristics, treatment history, and outcome data platelet count 10,000/ l. The first seven patients enrolled were also randomized to start day ϩ1 G-CSF in cycles 1 and 3 and placebo in cycles 2 and 4 versus placebo in cycles 1 and 3

Table 1 and G-CSF in cycles 2 and 4. All subsequent patients received G-CSF after each cycle starting day ϩ4. G-CSF was discontinued the day after the ANC was Ͼ1500/␮l. Engraftment Evaluation. The number of days to WBC and platelet engraftment was defined as the number of days after Initial therapy Predominant metastatic sites # Sites Visc Salvage therapy hematopoietic cell reinfusion (day 0) to ANC Ͼ500/␮l and platelets Ͼ20,000/␮l. The number of transfusion products (packed red cells or platelets) transfused was monitored after each cycle of chemotherapy. Toxicity Monitoring. Toxicity monitoring was graded using the Southwest Oncology Group common toxicity criteria. ER PGR Patients were removed from the trial for any grade III-IV

a nonhematological toxicity or for PD. Assessment of Response. Breast cancer lesions were assessed by physical examination and imaging studies at the start of high-dose therapy. Patients were evaluated before each

(yr) pre/post cycle of therapy with physical examination and chest X-ray. Age

pre/post, premenopausal or postmenopausal; ER, estrogen receptor; PGR, progesterone receptor; n, no; y, yes; p, positive; eq, equivocal; C, cyclophosphamide; A, doxorubicin; F,Computed 5-fluorouracil; tomographic reassessment, if applicable, was per- a formed after two cycles of therapy. CR, VGPR, and PR were 992 47 pre n eq CAF Sternum, soft tissue 2 n RT, TAM, Meg, CAF PR 3 VGPR CCR 1528 SPN 10031010 581016 451017 46 post1080 47 pre1094 38 pre p1170 33 pre1204 n 42 pre p1207 p 41 pre1211 eq p 39 pre RT, TAM1241 p p 43 pre CMF, RT1254 p n 36 pre CAF,1258 p p CMF 43 pre RT1319 n p 50 pre RT, Liver,1328 p n FAC adrenals 38 pre CAF, Chest n n CMF, wall 44 pre TAM Chest CMF, n p wall, RT pre cervical Liver, LN lungs CMF n n pre CAF eq p Chest wall, CAF, n p rib RT Spine, CAF, cervical RT p p LN Lungs, 2 liver, AC bone, p 2 ovary CMF, n TAM Omentum, CAF, n bone, CMF, LNs, TAM Supraclav, CW y cervical, 1 Supraclav, CMF, liver Axillary CW RT LN, 3 Bone, liver Taxol lung, 2 pleura, liver Lung, CAF 2 sternum, LN 2 5 n y Chest y 3 wall n AC Bone, paraspinal, n n BSO, liver, 4 TAM, None LNs Meg, CAF CAF, y Taxol RT, 2 RT, BSO, CAF, 2 TAM Taxol, 4 Surg, y 3 TAM Taxol, AC y NT n SD y MR y AT None CR AFM, AFM, C, RT, 1 Taxol, 3 FAC TAM 4 PR SD 4 n SD PR SD 1 CR PD Surg CR 4 MR PR 4 VGPR Deceased Alive* 4 4 VGPR 288 PD 3 CCR Deceased PR 2 977 CR PR Alive* 528 CR VGPR 4 PD 1500 PR PR Deceased 1370 4 Deceased Deceased Deceased 272 CR 1401 2 4 294 Alive* 272 PR PD Alive* CR 1016 VGPR Deceased Deceased 948 2 Deceased 238 586 96 n/a Deceased 55

M, methotrexate; T, paclitaxel; N,Visc, mitoxantrone; visceral; RT, Surg, radiotherapy; surgery; TAM, tamoxifen;HDC, Meg, high megace; dose BSO, chemotherapy; bilateral MR, salphingo-ophorectomy; Supraclav, minimal supraclavicular; response; LN,defined n/a, lymph not node; applicable; #, number CCR, of; continued complete response; Alive*, alive with disease; F/U, by follow-up. standard criteria: disappearance of all measurable

tumor; a Ն90% reduction in measurable lesions; and Ն50% Table 2 Time to recovery of absolute neutrophil count Ͼ500/␮l and reduction in the product of the bidimensional measurements, platelet count Ͼ20,000/␮l following each cycle of therapy respectively, for 4 weeks duration. Definitions for minimal Median time to recovery response, SD, and PD included: Ͻ50% reduction in disease; no Ն Days to Days to change in tumor size; and a 25% increase in tumor size or the ANC PLTs Interval to appearance of new lesions, respectively. Ͼ 500 Ͼ 20 K next cycle Treatment Following Recovery From High Dose Ther- Cycle #a (range) (range) (days) apy. Hormonal therapy for patients with receptor-positive tu- 1 16 10 (9–15) 11 (8–23) 24 (21–42) mors and/or radiation therapy to sites of prior disease were 2 15 10 (8–13) 10 (6–19) 25 (21–31) administered after recovery from high-dose therapy. 3 12 11 (9–17) 10 (9–17) 25 (21–45) 4 9 10 (8–17) 11 (8–16) Total 52 10 10 RESULTS a #, number of patients; PLT, platelet. Patient Data. Patient characteristics and outcome data are listed in Table 1. The median age was 43 years (range, 33–58 years). All but one patient had premenopausal primary with PBPCs, time to neutrophil and platelet recovery remained breast cancer. Prior primary treatment included the following: constant throughout the four courses of therapy when G-CSF all but two patients had received primary adjuvant chemother- was initiated on day ϩ1 of each cycle (20). At the time this apy; seven patients had been initially treated with a doxorubicin- present study was proposed, the impact of G-CSF after autolo- containing regimen; seven patients had previously undergone gous PBPC transplant was unclear. Therefore, a secondary aim primary treatment with radiotherapy; and four patients had was to determine whether G-CSF was necessary to accelerate received hormonal therapy. In the development of recurrent time to neutrophil or platelet recovery following infusion of disease, eight patients demonstrated visceral metastases, and “primed” PBPCs collected after recovery from chemotherapy eight patients manifested bony disease, with none of them and G-CSF. Patients received either G-CSF or placebo in alter- associated with bone-only disease. Salvage chemotherapy was nate cycles starting day ϩ1. To avoid an effect from initial cycle administered to 13 patients for a median of one regimen (range, or prior cycle G-CSF, patients were randomized to G-CSF in 0–3). Four patients received radiotherapy, and five patients had cycles 1 and 3 and placebo in cycles 2 and 4 versus G-CSF in hormonal manipulation for relapsed disease. Before enrollment, cycles 2 and 4 and placebo in cycles 1 and 3. The first seven all patients had received a doxorubicin-containing regimen. patients agreed to randomization. However, because the sixth Seven patients also had treatment with a paclitaxel-containing and seventh patients both refused postinfusion blinded treatment salvage regimen. The median number of prior chemotherapy after cycle 2, they received G-CSF in cycles 3 and 4. Because of regimens at the time of high-dose therapy was two (range, 1–4), patient preference and reports of the utility of posttransplant with the number of prior cycles of therapy being nine (range, G-CSF (21), this aspect of the protocol was suspended, and the 4–15). nine subsequent patients enrolled received G-CSF in each cycle. Mobilization Data. Fifteen of sixteen patients received The median number of days to WBC recovery (with and cyclophosphamide and G-CSF for the mobilization of PBPCs. without G-CSF) and platelet recovery after each cycle of ther- The median time to WBC recovery and initiation of apheresis apy are listed in Table 2. As listed in Table 3, 20 cycles of was 10 days (range, 9–13). All patients achieved the apheresis G-CSF or placebo were administered to seven patients on day goal of 10 ϫ 106 CD34ϩ cells/kg patient weight or the alternate ϩ1. The median time to WBC recovery using G-CSF was 10 goal of 100 ϫ 109 mononuclear cells/kg. The median number of days compared to placebo at a median of 13 days. Because there aphereses was 3 (range, 1–7). A median of 2 units of packed red were so few patients evaluable for this part of the study, only cells (range, 0–3) and zero platelet products (range, 0–3) were cycle 1 demonstrated a statistically significant WBC recovery transfused around the time of cell collection. The median num- time with the use of G-CSF after autograft infusion (P ϭ 0.048). ber of days from high-dose cyclophosphamide to commence- The median time to platelet recovery and the median number of ment of the multicycle therapy was 27 (range, 24–56). transfusions of packed RBCs and platelets were not statistically One patient did not receive cyclophosphamide because her significant between the groups who received G-CSF versus PBPCs had been collected with G-CSF, as specified in another placebo. The median number of transfusions administered at protocol from which she became ineligible when her disease each cycle are listed in Table 4. progressed through standard dose chemotherapy. Toxicities. The toxicities associated with this treatment Hematological Recovery (with or without G-CSF). To (Table 5) were primarily related to infections rather than organ infuse equivalent numbers of PBPCs at each cycle, each day’s toxicity. There were no cases of hemorrhagic cystitis, veno- apheresis collection was split into four equal fractions. Each occlusive disease of the liver, nor documented cardiac dysfunc- day’s quarter fraction was subsequently thawed and reinfused tion. There was one mortality secondary to fungemia. on day 0 of each cycle. The median number of mononuclear Infections. Despite prophylaxis with i.v. sulfamethox- cells infused per cycle was 2.8 ϫ 108/kg (range, 0.64–11.47 ϫ azole/trimethoprim, the first study patient developed PCP and 108). Of 10 patients for whom numbers of CD34ϩ cells are diffuse alveolar hemorrhage on day ϩ13 of cycle 3. She recov- available, the median number of CD34ϩ cells infused per cycle ered fully; nonetheless, a fourth cycle of therapy was not ad- was 3.15 ϫ 106/kg (2.2–5.0 ϫ 106). ministered. Patient SPN 1254 developed Candida tropicalis In our previous report on multiple cycle therapy supported sepsis in cycle 2. She experienced multiorgan failure and ex-

Table 3 The effect of G-CSF versus placebo on recovery of Table 4 Number of transfusions of packed RBCs and platelets with ANC Ͼ 500 by cycle on the seven patients randomized to each cycle of therapy posttransplant therapy Median number of transfusions Median time to recovery (range) (Days to ANC Ͼ 500) Cycle PRBCsa PLTs a ϩ ϩ b Cycle No. pts G-CSF No. pts Placebo P 1 4 (2–11) 3 (1–13) 1 3 10 4 13 0.048 2 5 (2–8) 3 (1–5) 2 4 8.5 2 12 0.10 3 4.5 (3–10) 2 (1–6) 3 2 14 2 14.5 1.00 4 6 (3–9) 2 (1–4) 4 2 11.5 1 17 0.54 a PRBC, packed RBC; PLT, platelet. Total 11 10 9 13 a No. pts, number of patients who received G-CSF or placebo by cycle. b Analysis performed by rank sum test. was 27% and at 3 years was 20%. Overall survival at 3 years was 31%. pired. Patient SPN 1094 developed cytomegalovirus pneumoni- DISCUSSION tis after completion of therapy. Three patients experienced re- Tumor response in the setting of recurrent disease may activation of dermatomal zoster. Overall, there were 10 episodes differ from that seen in the treatment of primary disease. Al- of bacteremia in eight patients and 1 episode of fungemia though the strategy of “high-dose sequential” or “dose-dense” throughout 52 cycles of high-dose combination therapy and 15 serial monotherapy over short intervals appears promising in the cycles of high-dose cyclophosphamide. Results of positive treatment of patients with newly diagnosed high-risk lymphoma blood cultures included Acinetobacter lwoffi, Enterobacter (22) and breast cancer (23, 24), its role in the treatment of cloace, Klebsiella pneumoniae, Streptococcus group D (entero- recurrent disease is unclear. Given the greater degree of tumor coccus), Bacillus, and Staphylococcus species. Only three pa- heterogeneity, administration of a single drug, even at a maxi- tients remained free of infectious complications at the conclu- mal dose, may kill only a small population of susceptible cells sion of therapy. Thirteen patients had at least one positive while allowing the remaining population of resistant cells to culture of blood, urine, stool, or bronchoalveolar lavage speci- proliferate. For patients with recurrent breast cancer, reports of mens for any infectious organism and/or developed dermatomal single-agent high-dose cyclophosphamide (60 mg/kg ϫ 2; Ref. zoster (three patients) before completion of therapy. 25) or melphalan (140–180 mg/m2; Ref. 26) used for cytore- Hospitalizations. All patients were hospitalized at least duction before myeloablative chemotherapy and autografting once during treatment, which included the initial high-dose have not demonstrated improvement in survival outcomes. Be- cyclophosphamide. There were 29 hospitalizations (range, 1–4 cause dose intensity and total dose appear to be important per patient), including four episodes of overnight (23 h) obser- factors in achieving CR and in the duration of response (27), vation during 67 courses (78%) of administered therapy. Dura- multiple-cycle high-dose combination therapy administered in tion of hospitalizations ranged from overnight to 42 days (20 relatively short intervals and supported with hematopoietic cells days in the intensive care unit). The diagnosis requiring hospi- may be the optimal treatment strategy for recurrent disease. talization in 25 cases was febrile neutropenia. In our previous report on four-cycle therapy supported with Treatment Outcome. Twelve patients completed at least PBPCs (20), we described the feasibility of repetitive cycles of three cycles of therapy (as shown in Table 1.) Three patients did high-dose mitoxantrone, 18 mg/m2, thiotepa, 150–200 mg/m2, not receive cycle 4: one developed PCP; one developed inter- and cyclophosphamide, 4500–5000 mg/m2. We subsequently stitial pneumonitis (treated with corticosteroids) and shingles; modified this regimen by adding paclitaxel at 150 mg/m2 and and a third was taken off the study for achievement of only SD escalating the thiotepa dose from 200 mg/m2 to 300 mg/m2 per after cycle 3. Four patients completed only one or two cycles of cycle.4 However, 10 of 18 patients experienced one or more therapy as follows: one expired after cycle 2; one patient was toxicities related to the cumulative dose of cyclophosphamide at removed from the study due to kinetically failing disease; one 18 g/m2. These included: hemorrhagic cystitis (four episodes), developed refractoriness to platelet transfusion support in cycle interstitial pneumonitis (five episodes), and cardiac dysfunction 1; and one had pneumonia and prolonged bacteremia associated (four episodes). Our present report resulted from the last mod- with venous thrombosis. Nine of 16 patients completed all four ification of multicycle treatment, which eliminated cyclophos- cycles of therapy. phamide from the repetitive cycle regimen, increased the mi- Including the initial course of cyclophosphamide, 67 (84%) toxantrone dose, increased the paclitaxel dose, and substituted of a planned total of 80 courses of chemotherapy and 52 (81%) melphalan (Alkeran) into the first two cycles (ATT). of a planned 64 cycles of high-dose combination therapy were The drugs included in our protocol have been used alone or delivered. As of March 31, 1999, the median follow-up was 1.5 in various combinations in the setting of high-dose therapy for years, with the longest follow-up of 4.2 years. Two patients stage IV or metastatic breast cancer. Melphalan and thiotepa are remained well without evidence of disease. Twelve patients alkylators with steep dose-response curves in breast cancer cell developed PD at 96–1358 days after high-dose therapy. The lines. In Antman’s initial review of intensive therapy with stem median duration of response was almost 9 months, and median cell support for breast cancer (28), a survey of clinical trials for survival was 18 months. Freedom from progression at 2 years advanced or refractory breast cancer using single agents yielded

Table 5 Regimen-related toxicities neuropathy were the most frequently noted side effects. How- ATT/MTT (No. of episodes) ever, two patients developed infections (PCP and cytomegalovirus pneumonitis) characteristic of T-cell immunodeficiency. a Toxicities CY (15 courses) HDT (52 courses) Although serious pulmonary infections may be found in T-cell- Fever (no source) 2 7 depleted autograft recipients (35), children undergoing au- TPN 1 tografting (36, 37), and those treated with immunosuppressive Hemorrhagic cystitis 0 Hospitalization 3 18 pretransplant therapies (38), we have not observed this morbid- Overnight Observation 4 ity with single-cycle autotransplants for breast cancer nor with Congestive heart failure 0 our prior multicycle regimens.4 Other centers have reported this Veno-occlusive disease of liver 0 rare complication in standard or high-dose chemotherapy, how- Interstitial pneumonitis 2 ever (39, 40). Review of both patients’ prior history and treat- Mortality 1 Infections ment did not yield information that would predict the develop- Herpes simplex virus 2 ment of these complications. Lymphocyte analysis was not Varicella zoster virus 3 performed at the time of these diagnoses; however, subsequent Bacteremia management included prolonged antimicrobial prophylaxis of Acinetobacter 1 Klebsiella 1 PCP. Because our prior regimens had included cyclophospha- Enterobacter 1 mide, thiotepa, mitoxantrone, and later paclitaxel, perhaps the Staphylococci 1 addition of melphalan to this high-dose combination regimen Streptococci 3 may have contributed to this type of immunocompromise. Micrococcus 1 The patients enrolled in this study generally had poor risk Bacillus 1 Catheter infection: Staph epi 1 features of disease. In our multivariate analysis of prognostic Fungemia variables associated with outcome after high-dose therapy for Candida albicans 1 patients with metastatic breast cancer (41), factors associated Urinary candidiasis 2 with poor outcome were identified and were similar to those for Pneumonia Pneumocystis carinii 1 women with breast cancer treated with standard therapies. These Cytomegalovirus 1 included hormone receptor-negative disease, the presence of visceral metastasis, two or more prior regimens, refractory dis- a CY, cyclophosphamide; HDT, high-dose therapy; TPN, total par- enteral nutrition. ease, and less than VGPR to high-dose therapy. Other groups have identified prior history of anthracycline exposure (42) as an additional adverse risk factor. In contrast, the achievement of CR to induction therapy and presence of metastasis to a single CRs only in patients treated with either high-dose melphalan site (43) are predictors of better outcome. In our study popula- (dose range, 120–180 mg/m2) or thiotepa (dose range, 180-1575 tion, all patients had received prior anthracycline therapy, with mg/m2.) In a dose-escalation study, melphalan, 100 mg/m2, and a median of two prior regimens. Eight patients demonstrated thiotepa, 500 mg/m2, were combined with busulfan at 12 mg/kg visceral metastases, and 13 patients had disease metastatic to in a single course of myeloablative therapy (29). Thiotepa (900 two or more sites. Only three patients had achieved minimal mg/m2) has been combined with mitoxantrone in dose escala- disease status before the time of high-dose therapy, all of whom tion to 50 mg/m2 (30, 31). Melphalan (180 mg/m2) with mitox- had metastasis to the chest wall that was resected. One of these antrone (60 mg/m2) constituted a myeloablative regimen that patients remains without evidence of disease, one patient died yielded promising results in patients treated to CR before high- from regimen-related toxicity, and the third progressed at 839 dose therapy (32). Paclitaxel has been escalated to 825 mg/m2 as days after high-dose therapy. Two other patients have done well; a single myeloablative dose (33) or in combination to 775 one continues without evidence of disease progression, and the mg/m2 with cyclophosphamide, 5625 mg/m2, and cisplatin, 165 other developed PD at 1358 days. Both patients had limited mg/m2 (34). Although the present study administered multidrug cycles of prior chemotherapy (one regimen each.) therapy over a 10-week span, the cumulative doses in this Another possible adverse determinant of outcome may be regimen (melphalan, 160 mg/m2, thiotepa, 1200 mg/m2, mitox- prior paclitaxel therapy. The development of drug resistance antrone, 60 mg/m2, and paclitaxel 800 mg/m2) exceed those mediated through the multidrug resistance model has been well- reported in studies of single-course high-dose therapies. documented for several drugs, including anthracyclines and Although the protocol aim was to administer chemotherapy taxanes, which are substrates for the p-glycoprotein receptor. In every 21 days, patients actually received treatment at a median this study, seven patients had also received paclitaxel treatment of 24-day intervals. Delays in therapy were usually due to slow before high-dose therapy. Of these patients, only one with chest WBC recovery or infectious complications. Cycles of therapy wall recurrence remains free of disease. All six other patients during which patients received placebo rather than G-CSF re- have since relapsed, with five having developed PD between sulted in a delay in WBC recovery (median, 13 days versus 10 147 and 270 days after high-dose therapy. The sixth patient days, respectively,) but not in red cell or platelet transfusion developed PD at 489 days after therapy. requirements. In conclusion, we have reported the results of a novel Regimen-related toxicity was moderate, with febrile neu- four-cycle regimen of high- dose melphalan, thiotepa, and pa- tropenia requiring hospitalization for all patients at some point clitaxel for two cycles followed by mitoxantrone, thiotepa, and during their treatment course. Otherwise, grade 1–2 diarrhea and paclitaxel for two cycles, with each cycle supported with hema-

topoietic progenitor cells. This therapy is feasible, but it is 8. Brufman, G., Colajori, E., Ghilezan, N., Lassus, M., Martoni, A., associated with a range of toxicities, including infectious com- Perevodchikova, N., Tosello, C., Viaro, D., and Zielinski, C. Doubling 2 2 plications. G-CSF administration after each PBPC infusion ac- epirubicin dose intensity (100 mg/m versus 50 mg/m ) in the FEC regimen significantly increases response rates. An international random- celerates time to neutrophil recovery but appears to have no ised phase III study in metastatic breast cancer. The Epirubicin High effect on red cell or platelet engraftment. The outcomes of this Dose (HEPI, 010) Study Group. Ann. Oncol., 8: 155–162, 1997. approach appear comparable to those reported to the North 9. Fisher, B., Anderson, S., Wickerham, D. L., DeCillis, A., Diitrov, N., American Bone Marrow Transplant Registry for single courses Mamounas, E., Wolmark, N., Pugh, R., Atkins, J. N., Meyers, F. 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Downloaded from clincancerres.aacrjournals.org on September 26, 2021. © 1999 American Association for Cancer Research. A Feasibility Study of Multiple Cycle Therapy with Melphalan, Thiotepa, and Paclitaxel followed by Mitoxantrone, Thiotepa, and Paclitaxel with Autologous Hematopoietic Cell Support for Metastatic Breast Cancer

Wendy W. Hu, Gwynn D. Long, Keith E. Stockerl-Goldstein, et al.

Clin Cancer Res 1999;5:3411-3418.

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