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Tandem autotransplants are used to treat advanced testis cancer patients but their value compared to a single autotransplant is unknown. To evaluate the results of autotransplant in relapsed testicular/germ cell cancer, data from 300 patients undergoing autotransplants 1989-2002 were reported to the Center for International Blood and Marrow Transplant Research. We compared results for those patients intended to undergo tandem autotransplant procedures (N = 102) versus patients in whom a second autotransplant was not planned (N = 198). Five-year survival probability was 35% (95% confidence interval = 25%-46%) in the planned tandem transplant cohort compared to 42% (35%-49%) in the group not planned to have a second transplant (P = .29). Probability of progression-free survival at 5 years for these cohorts was 34% (25%-44%) and 38% (31%-45%), respectively (P = .50). The planned tandem autotransplant cohort had significantly more advanced disease at diagnosis and greater likelihood of cisplatin resistance. Patients intended to receive tandem transplants had a lower treatment-related mortality at 1 year (3% versus 10%, P = .02). Using propensity score analysis the planned tandem autotransplant cohort had significantly lower treatment-related mortality (P = .044) but no different risk of relapse (P = .541) compared to the planned single transplant cohort. Tandem autotransplants for testicular cancer are associated with less treatment-related mortality than a planned single transplant, with no differences in disease-related outcomes or overall survival at 3 years. Patient selection bias for either transplant approach, however, may affect the results of this observational study; a randomized trial is needed to determine which approach, if either, is better.

Blood-derived progenitor cells obtained following mobilization with granulocyte colony-stimulating factor (MoPBSC) are increasingly being used as an alternative to bone marrow (BM) in allogeneic stem cell transplantation. The higher numbers of mature T lymphocytes in MoPBSC grafts may increase the risk of (chronic) graft-vs.-host disease. Counterflow centrifugal elutriation (CCE) is an effective method for T-cell depletion of BM grafts. The elutriation characteristics of steady-state BM and MoPBSC were compared using a CCE procedure in which fractions were obtained after small incremental increases in flow rate with constant centrifugal force. Counterflow centrifugal elutriation experiments with MoPBSC from six healthy volunteers showed that 54% of all cells collected were recovered in the < or = 15 mL/minute fractions, whereas experiments with mononuclear BM cells from five healthy volunteers resulted in recovery of 52% of collected cells from the > or = 19 mL/minute fractions. The peak concentrations of CD34+ cells were found in the same fraction (18 mL/minute), but more CD34+ cells from MoPBSC were recovered from the small (< or = 16 mL/minute) fractions (54% for MoPBSC, 26% for BM; p = 0.08). The small CD34+ cells from BM were more frequently lacking CD38 and human leucocyte antigen-DR expression than the small CD34+ cells from MoPBSC. Mature T-cells (CD3+) in BM and MoPBSC samples had similar CCE features, as did early (long-term culture initiating cells, high-proliferative potential colony-forming cells) and more mature (colony-forming units granulocyte/macrophage, BFU-e) hematopoietic progenitor cells. The results of this study suggest that T-cell depletion by CCE of MoPBSC as compared to BM products, may lead to a greater loss of CD34+ cells, but not of immature hematopoietic progenitor cells.

Using matched-pair analysis, we compared two popular methods of stem cell mobilization in 24 advanced-stage breast cancer patients who underwent two consecutive mobilizing procedures as part of a tandem transplant protocol. For the first cycle, 10 microg/kg/day granulocyte colony-stimulating factor (G-CSF) was given and apheresis commenced on day 4 and continued for < or =5 days (median 3 days). One week after the first cycle of apheresis, 4000 mg/m2 cyclophosphamide, 400 mg/m2 etoposide, and 10 microg/kg G-CSF were administered for < or =16 days (cycle 2). Apheresis was initiated when the white blood cell (WBC) count exceeded 5000 cells/microL and continued for < or =5 days (median 3 days). Mean values of peripheral blood WBC (31,700+/-3200 vs. 30,700+/-3300/microL) were not significantly different between cycles 1 and 2. Mean number of mononuclear cells (MNC) collected per day was slightly greater with G-CSF mobilization than with the combination of chemotherapy and G-CSF (2.5+/-0.21x10(8) vs. 1.8+/-0.19x10(8) cells/kg). Mean daily CD34+ cell yield, however, was nearly six times higher (12.9+/-4.4 vs. 2.2+/-0.5x10(6)/kg; p = 0.01) with chemotherapy plus G-CSF. With G-CSF alone, 13% of aphereses reached the target dose of 5x10(6) CD34+ cells/kg in one collection vs. 57% with chemotherapy plus G-CSF. Transfusions of red blood cells or platelets were necessary in 18 of 24 patients in cycle 2. Three patients were hospitalized with fever for a median of 3 days after cycle 2. No patients received transfusions or required hospitalization during mobilization with G-CSF alone. Resource utilization (cost of drugs, aphereses, cryopreservation, transfusions, hospitalization) was calculated comparing the median number of collections to obtain a target CD34+ cell dose of 5x10(6) cells/kg: four using G-CSF vs. one using the combination in this data set. Resources for G-CSF mobilization cost $7326 vs. $8693 for the combination, even though more apheresis procedures were performed using G-CSF mobilization. The cost of chemotherapy administration, more doses of G-CSF, transfusions, and hospitalizations caused cyclophosphamide, etoposide, and G-CSF to be more expensive than G-CSF alone. A less toxic and less expensive treatment than cyclophosphamide, etoposide, and G-CSF is needed to be more cost-effective than G-CSF alone for peripheral blood progenitor cell mobilization.