Cyclophosphamide and paclitaxel as initial or salvage regimen for the mobilization of peripheral blood progenitor cells

Transcription

1 Bone Marrow Transplantation, (1999) 24, Stockton Press All rights reserved /99 $ Cyclophosphamide and paclitaxel as initial or salvage regimen for the mobilization of peripheral blood progenitor cells JL Klein, PM Rey, R Dansey, C Karanes, E Abella, L Cassells, C Hamm, M Flowers, C Couwlier, WP Peters and RD Baynes Bone Marrow Transplantation, Division of Hematology and Oncology, Barbara Ann Karmanos Cancer Institute, and Wayne State University, Detroit, MI, USA Summary: Peripheral blood progenitor cells are now commonly used for hematologic reconstitution after myelosuppressive chemotherapy for hematologic and solid malignancies. The purpose of this study was to evaluate the activity of paclitaxel 170 mg/m 2 and cyclophosphamide 2 g/m 2 (CP) with filgrastim (human G-CSF) for mobilization of PBPCs as the first or second maneuver after failure with filgrastim alone. Sixty-four patients with stage II IV breast cancer received (CP) followed by filgrastim (10 g/kg/day). In 35 (55%) this was the first maneuver while it was for salvage in 29 (45%) patients. The median number of aphereses was two (range, 1 7). In 83% of the patients apheresis was initiated on days following chemotherapy. The median numbers of CD34 + cells/kg, CD34 + cells/apheresis/kg and total nucleated cells/kg collected were ( ), ( ) and (9 660), respectively. All the patients yielded at least CD34 + cells/kg. CP mobilization salvaged the 29 patients who failed mobilization with filgrastim alone. When used as first-line mobilization the yield of CD34 + cells 10 6 /kg was higher than in the salvage group (16.93 vs 3.94, P 0.001). Patients receiving CP as salvage reached the target of CD34 + cells/kg in only 45% (13/29) of cases vs 94.3% as first maneuver. CP followed by filgrastim is a safe and effective regimen for the mobilization of PBPCs in patients with breast cancer and shows significant activity in patients who failed to mobilize with filgrastim, suggesting a higher mobilization potential. Keywords: PBPC; mobilization; CD34 selection; Isolex 300i accelerate the tempo of engraftment compared to bone marrow cells, thereby reducing morbidity, mortality, support measures required and economic costs. 1 4 In addition, PBPCs can be collected in an outpatient setting with minimal morbidity avoiding the operative procedure of BM harvest. Hematopoietic growth factors alone can provide an adequate yield of stem cells to ensure hematological reconstitution after HDC. Collection of PBPCs after CT followed by cytokines takes advantage of the additional mobilizing effect of the myelosuppressive drugs. The use of chemotherapy has been recognized to increase PBPC yields compared to cytokines alone, therefore requiring fewer apheresis procedures. 5,6 In spite of the extensive experience acquired in this area, it is not known which is the best regimen to mobilize hematopoietic progenitor cells. Mobilization with disease-oriented chemotherapy together with cytokines may be also combine the advantage of antitumor activity with PBPC mobilization. 7,8 Paclitaxel and cyclophosphamide are both active in breast cancer and share a similar pattern of hematological recovery. The value of a combination of paclitaxel and cyclophosphamide as a mobilization regimen in patients with ovarian and breast cancer has already been described. 9,10 One of the problems associated with the use of PBPCs is the variability in the number of cells collected between patients, partly because of the amount of previous treatment Moreover, cytokines by themselves will fail to mobilize stem cells in 10% of patients. 5,11,15 Some of these patients still will be salvaged adding chemotherapy, higher doses of growth factors or both, but the ideal salvage regimen is controversial. 16 Our report studies the efficacy of paclitaxel 170 mg/m 2 and cyclophosphamide 2 g/m 2 (CP) with filgrastim, and particularly analyzes its value as a salvage maneuver after failure to mobilization by filgrastim alone. Within the last decade mobilized peripheral blood progenitor or stem cells (PBPC) have emerged as the most common source of hematopoietic cells for support following highdose chemotherapy (HDC). Various combinations of cytokines or myelosuppressive chemotherapy (CT) and cytokines have been used to mobilize PBPCs. PBPC infusions Correspondence: Dr JL Klein, Karmanos Cancer Institute, 3990 John R, 4 Brush South, Detroit, Michigan 48201, USA Received 11 March 1999; accepted 23 June 1999 Patients and methods Patients Between November 1996 and January women with stage II IV breast cancer underwent PBPC collection after paclitaxel 170 mg/m 2 and CP 2 g/m 2 followed by subcutaneous filgrastim. Thirty-five (55%) patients were mobilized in this fashion as first maneuver, and 29 (45%) after a prior, unsuccessful attempt with filgrastim 10 g/kg alone

2 960 (45%) (Table 1). Thirty-two patients who had either bone marrow involvement or multiple skeletal metastasis were involved in a protocol for CD34 selection as a means of tumor purging and had CD34 positive enrichment of the PBPC production after collection using the Isolex 300i (Baxter Healthcare Corporation, Irvine, CA, USA). Patients could have received prior chemotherapy for metastatic disease. As part of this protocol, patients underwent initial PBPC mobilization with CP. Three additional patients with high risk primary breast cancer either stage II (one) or III (two) received CP as the initial mobilization regimen. These patients had mobilization with CP because of delays in obtaining insurance coverage and received chemotherapy because of the length of time since their last chemotherapy. Patients who were initially mobilized with filgrastim but did not produce CD34 + /kg underwent salvage mobilization. Patients given filagrastim had received 10 g/kg for 4 days. On the fifth day PB CD34 + cells were enumerated by FACS analysis. Patients with 10/ l were started on leukapheresis and continued for 3 days. If the PB CD34 + cell count was 10 l, patients were continued on filgrastim and PB CD34 + cells were again checked. If the PB CD34 + cells remained below 10/ l for 3 days they were considered mobilization failures and proceeded to CP mobilization. Patients who had 10 CD34 + cells/ l and started PBPC collection but did not yield CD34 + cell/kg within 3 days and had a falling PB CD34 + cell count were also considered mobilization failures and proceeded to CP mobilization. No patients received a second mobilization with filgrastim at either the same or an increased dose. Five of the women who received CP, as the second mobilization regimen had stage II disease and 24 (83%) had stage IV disease. The median number of chemotherapy cycles either adjuvantly and/or for metastatic disease was 10 (range, 3 26) and eight (range, 3 24), for patients undergoing mobilization as a first or salvage maneuver, respectively. Mobilization On day 1 paclitaxel 170 mg/m 2 was diluted in 500 cc D5W in a glass container with a polyethylene-line tubing and a 0.22 m in-line filter and infused over 24 h intravenously. Patients were premedicated with dexamethasone 20 mg orally 12 and 6 h before paclitaxel and dexamethasone 20 mg i.v., diphenhydramine 50 mg i.v. and cimetidine 300 mg i.v. 20 min before paclitaxel administration. Cyclophosphamide 2.0 g/m 2 was given intravenously 1 h after the completion of the paclitaxel. Cyclophosphamide was infused over 1 h. All patients received MESNA for the prevention of hemorrhagic cystitis. The MESNA dose was 2.0 g/m 2 as equally divided administrations prior to infusion of CP and 4 and 8 h after. Following chemotherapy patients received filgrastim 10 g/kg/day subcutaneously. Patients also received ciprofloxacin, 500 mg three times a day as bacterial prophylaxis. Collection and cryopreservation of PBPC Following the administration of the chemotherapy and filgrastim, patients had complete blood counts measured every other day and began apheresis when the WBC count was at least /ml. Daily apheresis procedures were performed using a Fenwall CS 3000 plus cell separator (Fenwall, Baxter Healthcare Corporation, Round Lake, IL, USA). Sixteen liters were processed per procedure, using continuous flow centrifugation at a flow rate of 70 ml/min. The target was to collect CD34 + cells/kg, but attempts were made to collect a minimum of cells/kg. The final product containing 10% DMSO and autologous plasma was frozen in a liquid nitrogen controlled-rate freezer and was maintained in the liquid phase of liquid nitrogen. High-dose chemotherapy regimens All but three patients received cisplatin, CP and BCNU (STAMP I) followed by PBPC infusion. Cyclophosphamide, cisplatin and BCNU: Sixty-one patients received cyclophosphamide (1875 mg/m 2 /day) days 6 to 4, cisplatin (165 mg/m 2 ) continuous i.v. infusion days 6 to 4, and BCNU (600 mg/m 2 ) on day 3, as follows. Actual body weight was used to calculate the therapeutic doses of all agents unless the actual body weight was 20% greater than the ideal body weight. In the event that the actual body weight was 20% greater the average of the ideal and actual body weight was used to calculate the therapeutic doses. PBPCs were reinfused 3 days after the completion of the regimen. Patients received fil- Table 1 Patient characteristics Overall Initial maneuver Salvage regimen n (%) (55%) 29 (45%) Age (median and range) 47 (22 71) 45 (22 59) 48 (26 71) Stage II 6 (9.5%) 1 (3%) 5 (17%) III 2 (3%) 2 (6%) 0 IV 56 (87.5%) 32 (91%) 24 (83%) Prior radiotherapy 36 (56%) 16 (46%) 20 (69%) No. of prior cycles of chemotherapy 9.5 (3 26) 10 (3 26) 8 (3 24) No. of prior chemotherapy regimens 2 (1 3) 2 (1 3) 2 (1 3) Bone marrow involvement 14 (22%) 12 (34%) 2 (7%) Bone metastasis ( 3 sites) 35 (55%) 25 (71%) 10 (34%)

3 grastim 5 g/kg/day s.c. starting 3 h after the completion of the PBPC infusion. Patients were discharged from hospital after the PBPBC infusion and followed daily in the outpatient transplantation clinic. Ifosphamide, dacarbazine and melphalan: Three patients received ifosphamide (6000 mg/m 2 ), melphalan (120 mg/m 2 ) and dacarbazine (1000 mg/m 2 ). Measurement of CD34 + cells Peripheral blood was analyzed prior to apheresis for CD34 + cell counts using flow cytometry. An aliquot of each apheresis product was collected and the CD34 + cell content measured. CD34 + cell enumeration was performed as previously described. 17 Statistics Statistical comparisons were made with SPSS software. The Mann Whitney, Wilcoxon and Kruskal Wallis tests were used for non-parametric analyses. Proportions were compared using chi-square or Fisher s exact method, as appropriate. Multivariate associations were assessed using a multiple regression model. Factors were included in a stepwise manner. Time to collect at least 2.5 and CD34 + cells and time to initiate apheresis were estimated using the product-limit method according to Kaplan and Meier and comparisons made by Breslow test. Results PBPC collections PBPC collection was initiated when the WBC was /l. The median day for starting apheresis was day 10 after receiving the mobilizing chemotherapy (range, 7 17). The date of initiating leukapheresis following CP was very consistent, with more than 80% of patients starting the collections on days 10 or 11. There was no statistically significant difference in the day to start the apheresis between the two groups. On the first day of collection the median WBC and CD34 + cell counts were /ml ( ) and 23/ l (range, 1 340), respectively. Patients underwent a median of two (range, 1 8) apheresis procedures which provided a median yield per patient of total nucleated cells ( ) and ( ) CD34 + cells/kg. There was a strong correlation between the number of preleukapheresis circulating CD34 + cells/ l and the CD34 + cells per kilogram in the apheresis collection (r = 0.82, P 0.001). All patients reached a minimum collection of CD34 + cells/kg. Sixty-two per cent of patients collected and 52% CD34 + cells/kg with the first apheresis (Figures 1 and 2). The number of CD34 + cells collected on the first day of apheresis was superior to the second or subsequent days. Comparisons between the primary mobilization and salvage mobilization groups are shown in Table 2. There was a significant difference in the number of CD34 + cells collected between the group that had CP as % Patients Days of apheresis Overall First Salvage Figure 1 Probability of reaching a target of CD34 + cell/kg for patients undergoing first or salvage mobilization. % Patients Days of apheresis Overall First Salvage Figure 2 Probability of reaching a target of CD34 + cell/kg for patients undergoing first or salvage mobilization. the first mobilization procedure and patients who received CP as a salvage procedure after failing PBPC collection with filgrastim alone. The median collection was CD34 + cells/kg in patients receiving CP as salvage, compared with CD34 + cells/kg when CP was used as first mobilization (P 0.001). Four patients in the salvage group (13.7%) did not achieve the target number of and 16 did not collect , vs 0 and 2, respectively, in the initial mobilization group (P 0.001). Analysis of prognostic factors of mobilization Patients characteristics were analyzed for factors that influenced CD34 + cell collection including age, stage of disease at the time of HDC, bone marrow involvement, number of prior regimens and chemotherapy cycles, prior radiotherapy, and order of mobilization. Only the last was associated with worse PBPC yields and was a predictive factor for failure to collect at least CD34 + cells (Table 3). Engraftment kinetics after PBPCT All but one patient who progressed during induction proceeded to high-dose chemotherapy and PBPCT. In 25 patients who received the selected CD34 + PBPC, the median day to reach an absolute neutrophil count of /l and unsustained platelet count of /l were 961

4 962 Table 2 Collection results by order of mobilization Overall Initial mobilization Salvage mobilization No. aphereses 2 (1 8) 2 (1 5) 2 (1 8) CD /kg 8.72 ( ) ( ) 3.94 ( ) CD /kg/apheresis 3.97 ( ) 7.37 ( ) 1.65 ( ) First apheresis CD34 + cells 10 6 /kg 3.16 ( ) 7.35 ( ) 1.05 ( ) Collection of CD34 + cells/kg 60/64 (93%) 35/35 (100%) 24/29 (83%) Collection of CD34 + cells/kg 46/64 (72%) 33/35 (94.3%) 13/29 (45%) Table 3 Regression analysis of prognostic factors influencing the total number of CD34 + cells/kg collected Factor r P Timing (first or salvage mobilization) Age Bone marrow invasion No. of prior CT cycles (range, 8 11) and 17 (range, 13 29), respectively, after the PBPC infusion. For patients receiving the unselected PBPC infusion the median days to reach an absolute neutrophil count of /l and platelet count of /l were 9 (range, 8 11) and 16 (range, 11 60), respectively, after the PBPC infusion. Toxicity of the regimen Nine patients (14%) required admission because of febrile neutropenia (two catheter infections caused by S. epidermidis and by S. aureus, one patient presented with sinusitis and bronchitis and six patients had no documented bacteriological or clinical infection). No differences were observed between first and salvage mobilizations. No procedurerelated deaths occurred. Discussion Paclitaxel is now a well-established agent in the treatment of breast cancer, with significant activity even in doxorubicin-resistant tumors. 18 Paclitaxel causes less thrombocytopenia, does not have cumulative hematological toxicity and seems to spare the pool of primitive stem cells. 19 These factors make it an optimal tool to mobilize PBPCs in breast cancer patients. Paclitaxel has been used alone 20 or combined with either CP 9,10,21 23 or epirubicin 24,25 for PBPC mobilization. CP has been tested with different schedules and doses, ranging for paclitaxel between mg/m 2 and 2 4 g/m 2 for CP. Paclitaxel in combination with CP improves the mobilization of PBPCs vs CP alone, without a major increase in toxicity, particularly febrile neutropenia. We have used a lower dose of CP (2 g/m 2 ) in order to diminish the associated toxicity without compromising the efficacy. The resulting combination provided successful mobilizations in all of the patients to reach a dose of CD34 + cells/kg, as our results and others confirm. 10 CP also fulfilled another important requirement of a mobilization protocol, namely, predictable timing eliminating one of the criticisms of the use of chemotherapy as mobilization. This is influenced by the amount of previous chemotherapy and radiation treatment. CP accomplishes both safe and predictable mobilization in our poor prognostic group for mobilization. In addition, leukapheresis could be started on day 10 or 11 in 90% of patients as first attempt. There is increasing evidence for faster recovery with higher doses of PBPCs infused. 15,26,27 This emphasizes the practical importance of effective mobilization in breast cancer patients in order to improve the CD34 + cell yields. 5,11 14 However, even with no or limited prior antineoplastic treatment, the number of PBPCs collected is variable among patients and 10% of them will fail to mobilize successfully. There is no agreement on the best regimen after initial failure to mobilize PBPCs by cytokines. Higher doses of filgrastim, cocktails of growth factors or chemotherapy and growth factors provided mobilization rates below 50%. 16 In our series, CP successfully salvaged the 29 patients who failed a first mobilization with filgrastim alone. These results are more important if we consider the adverse prognostic factors for mobilization exhibited in our series, such as a large amount of prior chemotherapy extensive bone disease, marrow involvement and prior radiotherapy. 5,11 14,23 Interestingly, none of these factors were significantly worse in salvage mobilizations than in patients mobilized as first attempt. With initial CP in the current study, all but two patients reached the target of CD34 + cells/kg with a median of two (1 7) collections, as compared with 13/29 patients who received salvage CP. The yield of CD34 + cells and average CD34 + cells/kg/apheresis collected were significantly lower (P 0.001) in the salvage patients. Moreover, the only prognostic factor associated with the number of CD34 + cells collected per apheresis after CP was the failure to mobilize adequate PBPCs with filgrastim alone. This information suggests that various factors affect the mobilization of PBPC whether the patients received growth factor alone or CP plus growth factor. Because of the success of this regimen for patients on our CD34 + cell selection protocol we elected to use the CP mobilization rather than a second course of higher dose filgrastim. We were successful in collecting an adequate PBPC product in all patients salvaged with this regimen. The PBPC product was able to provide a rapid hematological recovery after transplant in all patients. We have used a lower dose of CP than was originally reported for mobilization with paclitaxel and CP. 5 There were no episodes of hematuria associated with our regimen

5 and the incidence of febrile neutropenia (14%) was lower than reported with CP (4 g/m 2 ) and paclitaxel (170 mg/m 2 ), 5 although this may have been related to the use of MESNA and prophylactic antibiotics during the neutropenic period. In summary, CP is a highly effective method for mobilizing PBPCs, both as initial approach and as a salvage maneuver after failure to yield adequate PBPC product with filgrastim alone. It provided a sufficient number of hematopoietic progenitor cells to support HDC in all patients, suggesting a higher efficacy of CP plus filgrastim over filgrastim alone. References 1 Henon R, Liang H, Beck-Wirth G et al. Comparison of hematopoietic and immune recovery after autologous bone marrow or blood stem cell transplants. Bone Marrow Transplant 1992; 9: To LB, Roberts MM, Haylock DN et al. Comparison of haematological recovery times and supportive care requirements of autologous recovery phase peripheral blood stem cell transplants, autologous bone marrow transplants and allogeneic bone marrow transplants. Bone Marrow Transplant 1992; 9: López M, Mortel O, Pouillart P et al. Acceleration of hematopoietic recovery after autologous bone marrow transplantation by low doses of peripheral blood stem cells. Bone Marrow Transplant 1991; 7: Peters WP, Rosner G, Ross M et al. Comparative effects of GM-CSF and G-CSF on priming peripheral blood progenitor cells for use with autologous bone marrow after high dose chemotherapy. Blood 1993; 81: Bensinger W, Appelbaum F, Rowley S et al. Factors that influence collection and engraftment of autologous peripheralblood stem cells. J Clin Oncol 1995; 13: Alegre A, Tomas JF, Martinez-Chamorro C et al. Comparison of peripheral blood progenitor cell mobilization in patients with multiple myeloma: high-dose cyclophophamide plus GM-CSF vs G-CSF alone. Bone Marrow Transplant 1997; 20: Venturini M, DelMartro L, Melioli G. Release of peripheral blood progenitor cells during standard dose cyclophosphamide, epidoxorubicin, 5-fluorouracil regimen plus granulocyte colony stimulating factor for breast cancer therapy. Cancer 1994; 74: Olivieri A, Offidani M, Ciniero L et al. DHAP regimen plus G-CSF as salvage therapy and priming for blood progenitor cell collection in patients with poor prognosis lymphoma. Bone Marrow Transplant 1995; 16: Demirer T, Rowley S, Buckner CD et al. Peripheral-blood stem-cell collections after paclitaxel, cyclophosphamide, and recombinant human granulocyte colony-stimulating factor in patients with breast and ovarian cancer. J Clin Oncol 1995; 13: Weaver CH, Schwartzberg LS, Birch R et al. Collection of peripheral blood stem cells following administration of paclitaxel, cyclophosphamide and G-CSF in patients with breast and ovarian cancer. Biol Blood Marrow Transplant 1997; 3: Bensinger WI, Longin K, Appelbaum F et al. Peripheral blood stem cells collected after recombinant granulocyte colony stimulating factor: an analysis of factors correlating with the tempo of engraftment after transplantation. Br J Haematol 1994; 87: Haas R, Möhle R, Früehauf S. Patient characteristics associated with successful mobilizing and autografting of peripheral blood progenitor cells in malignant lymphoma. Blood 1994; 83: Kotasek D, Shepherd KM, Sage RE et al. Factors affecting blood stem cell collections following high-dose cyclophosphamide mobilization in lymphoma, myeloma and solid tumors. Bone Marrow Transplant 1992; 9: Schwartzberg LS, Birch R, Hazelten B et al. Peripheral blood stem cell mobilization by chemotherapy with and without r- h-filgrastim. J Hematother 1992; 1: Weaver CH, Hazelton B, Birch R et al. An analysis of engraftment kinetics as a function of the CD34 content of peripheral blood progenitor cell collections in 692 patients after the administration of myeloablative chemotherapy. Blood 1995; 86: Weaver CH, Tauer K, Zhen B et al. Second attempts at mobilization of peripheral blood stem cells in patients with initial low CD34+ cell yields. J Hematother 1998; 7: Sutherland DR, Anderson L, Keeney M et al. The ISHAGE guidelines for CD34+ cell determination by flow cytometry. J Hematother 1996; 5: Seidman AD, Crown JPA, Reichman B et al. Lack of clinical cross resistance of paclitaxel with anthracycline in the treatment of metastatic breast cancer. Proc Am Soc Clin Oncol 1993; 12: 63 (Abstr. 53). 19 Shea TC. Mobilization of peripheral blood progenitor cells with paclitaxel-based chemotherapy. Semin Oncol 1997; 107 (Suppl. 2): Holmberg LA, Demirer T, Rowley S et al. High-dose busulfan, melphalan and thiotepa followed by autologous peripheral blood stem cell (PBSC) rescue in patients with advanced stage III/IV ovarian cancer. Bone Marrow Transplant 1998; 22: Raptis G, Tiersten A, Fennelly D et al. The addition of paclitaxel to high dose cyclophosphamide + G-CSF markedly enhances the mobilization of CD34+ peripheral blood progenitor cells in patients with responding metastatic breast cancer undergoing high dose chemotherapy. Proc Am Soc Clin Oncol 1995; 14: 313 (Abstr.). 22 Pedrazzoli P, Perotti C, Da Prada GA et al. Collection of circulating progenitor cells after epirubicin, paclitaxel and G- CSF in patients with metastatic breast cancer. Br J Cancer 1997; 75: Demirer T, Buckner D, Storer B et al. Effect of different chemotherapy regimens on peripheral-blood stem-cell collections in patients with breast cancer receiving granulocyte colony-stimulating factor. J Clin Oncol 1997; 15: Conte PF, Gennari A, Salvadori B et al. Paclitaxel plus epirubicin in advanced breast cancer. Oncology 1998; 12 (Suppl. 1): Bengala C, Pazzagli I, Tibaldi C et al. Mobilization, collection, and characterization of peripheral blood hemopoietic progenitors after chemotherapy with epirubicin, paclitaxel, and granulocyte-colony stimulating factors administered to patients with metastatic breast carcinoma. Cancer 1998; 82: Watts MJ, Sullivan AM, Jamieson E et al. Progenitor-cell mobilization after low-dose cyclophosphamide and granulocyte colony-stimulating factor: an analysis of progenitor-cell quantity and quality and factors predicting for these parameters in 101 pretreated patients with malignant lymphoma. J Clin Oncol 1997; 15: Pecora AL, Preti RA, Gleim GW et al. CD34+CD33 cells influence days to engraftment and transfusion requirements in autologous blood stem-cell recipients. J Clin Oncol 1998; 16: