High dose cyclophosphamide: stem cell mobilizing capacity in 21 patients

Initial Results of Peripheral-Blood Stem-Cell Mobilization, Collection, Cryopreservation, and Engraftment After Autologous Transplantation Confirm That the Capacity-Building Approach Offers Good Chances of Success in Critical Contexts: A Kurdish-Italian Cooperative Project at the Hiwa Cancer Hospital, Sulaymaniyah

Introduction

At Hiwa Cancer Hospital (Sulaymaniyah, Iraqi Kurdistan) after the center was started by a cooperative project in June 2016, autologous transplantation was developed.

Patients and Methods

To develop the project, the capacity-building approach was adopted, with on-site training and coaching of personnel, educational meetings, lectures, on-the-job training, and the implementation of quality management planning.

Results

Here, we report initial results of peripheral-blood stem-cell mobilization and collection of the first 27 patients (age 12 to 61 years; 19 males and 8 females; multiple myeloma, n = 10; plasma cell leukemia, n = 1; Hodgkin lymphoma, n = 12; non-Hodgkin lymphoma, n = 3; and acute myeloid leukemia, n = 1). Only three (11.5%) of 26 patients experienced a failure of mobilization. A median of 6.1 × 10⁶/kg CD34-positive cells per patient were collected (range, 2.4 to 20.8), with two apheretic runs. Twenty-four patients underwent autologous transplantation. All but one transplantation engrafted fully and steadily, with 0.5 and 1.0 × 10⁹/L polymorphonucleates on day 10.5 (range, 8 to 12) and day 11 (range, 9 to 15), respectively, and with 20 and 50 × 10⁹/L platelets on day 13 (range, 10 to 17) and day 17 (range, 2 to 44), respectively. More than 95% of patients are projected to survive 1 year after autograft.

Conclusion

These data are the result of an Italian effort to establish in Iraqi Kurdistan a leading center for hemopoietic stem-cell transplantation. The capacity building approach was used, with on-site training and coaching as instruments for the development of provider ability and problem solving. With future limitations for immigration, this method will be helpful, especially in the field of high-technology medicine.

Peripheral blood stem cell mobilization for high-dose chemotherapy

Several studies have clearly documented a more rapid hematopoietic recovery with growth factor-mobilized PBSC than with bone marrow. Time to engraftment for neutrophils and platelets average 8-12 days in contrast to 2-4 weeks after bone marrow. This rapid hematopoietic recovery with PBSC has decreased the duration of hospitalization, transfusion requirements, and costs. Although growth factors alone may mobilize enough PBSC for high-dose chemotherapy, administration of growth factor after submyeloablative chemotherapy increases the yield of CD34+ cells. Based on the current data, CD34+ cell content of PBSC appears to be the single most powerful predictor of hematopoietic recovery. Infusion of > or =5 x 10(6) CD34+ cells/kg is associated with a rapid engraftment of neutrophils and platelets, although successful engraftment has also been reported with infusion of 2.5-5 x 10(6) CD34+ cells/kg. Age, prior radiotherapy, marrow involvement, and prior chemotherapy regimens are important factors influencing the yield of stem cells. Therefore, using these pa-rameters, we may identify the patients who will fail to mobilize sufficient numbers of PBSC before collection and use new strategies for stem cell mobilization. Because of the ease of collection and rapid engraftment after myeloablative therapy, PBSC have replaced bone marrow for autologous transplantation and may supplant bone marrow for allogeneic transplantation in the near future.

A randomized trial of two doses of cyclophosphamide with etoposide and G-CSF for mobilization of peripheral blood stem cells in 318 patients with stage II-III breast cancer

The purpose of this study was to develop a less toxic outpatient chemotherapy regimen for mobilizing peripheral blood stem cells (PBSC). Three hundred eighteen patients with newly diagnosed stage II-III breast cancer who had received conventional dose adjuvant chemotherapy were randomized to receive intermediate-dose cyclophosphamide (2 g/m2), etoposide (600 mg/m2), and granulocyte colony-stimulating factor (G-CSF) 6 micrograms/kg/day (ID-Cy, n = 162) or high-dose cyclophosphamide (4 g/m2) and the same doses of etoposide and G-CSF (HD-Cy, n = 156) followed by collection of PBSC. Three hundred seventeen of 318 patients had apheresis performed, and 315 received high-dose chemotherapy (HDC) followed by PBSC support. The median numbers of CD34+ cells collected in a median of two apheresis following ID-Cy and HD-Cy were 19.9 and 22.2 x 10(6)/kg, respectively (p = 0.04). The fractions of patients achieving CD34+ cell doses > or = 2.5 or > or = 5.0 x 10(6)/kg were not different between the two regimens. More patients receiving HD-Cy had grade 3-4 nausea (p = 0.001), vomiting (p = 0.03), and mucositis (p = 0.04). The fractions of patients having a neutrophil nadir < 0.5 x 10(9)/L following ID-Cy and HD-Cy were 0.83 and 0.95, respectively (p = < 0.001). The fractions of patients having a platelet nadir < 25 x 10(9)/L following ID-Cy and HD-Cy were 0.13 and 0.51, respectively (p = < 0.001). More patients in the HD-Cy group received platelet (p < 0.001) and red blood cell (p < 0.001) transfusions and were admitted to the hospital more frequently (p = 0.03) than patients receiving ID-Cy. Three hundred fifteen patients received HDC followed by infusion of PBSC. There were no significant differences in the incidence of transplant-related death or early survival between patients receiving ID-Cy or HD-Cy followed by HDC. It was concluded that a regimen of Cy 2 g/m2 with etoposide and G-CSF was effective for mobilization of PBSC with low morbidity and resource utilization in patients with limited prior chemotherapy exposure.

Optimization of peripheral blood stem cell mobilization

Peripheral blood stem cells (PBSC) are increasingly utilized in lieu of marrow for hematopoietic support due to the ease of collection and the rapid kinetics of recovery relative to bone marrow (BM). Neutrophil and platelet recovery times after PBSC transplantation average less than 8-12 days after infusion in contrast to the usual two to four weeks experienced after BM transplantation. This has simplified autologous transplantation and made it safer because patients require fewer days of antibiotic and blood component support and are discharged earlier from the hospital. The administration of hematopoietic growth factors during recovery from high-dose chemotherapy increases the number of circulating hematopoietic progenitor cells to levels as much as 1,000-fold greater than levels normally found in blood and 10-50 times greater than with chemotherapy alone. More recently, it has been shown that adequate numbers of PBSC can be collected using growth factors alone without prior chemotherapy. Although not yet universally accepted, the CD34+ cells content of PBSC appears to be the single most powerful predictor of recovery kinetics in patients receiving myeloablative therapy and PBSC infusion. Infusion of > 5 x 10(6) CD34+ cells/kg is associated with a rapid engraftment of neutrophils and platelets, although successful engraftment has also been reported with the infusion of 2.5-5 x 10(6) CD34+ cells/kg. By measuring the CD34 or colony forming units-granulocyte-macrophage (CFU-GM) content of PBSC collections, mobilization chemotherapy and cytokine regimens, age, marrow disease, prior radiation and prior chemotherapy treatment have been found to be important factors influencing the numbers of stem cells collected. The current challenge for clinical investigators is to improve methods of identifying patients who will fail to mobilize sufficient numbers of PBSC prior to collection and to utilize new strategies for stem cell mobilization. The relative ease of collection and the rapid engraftment after myeloablative therapy suggest that PBSC will likely supplant marrow for both allogeneic and autologous transplantation in the next five years.