The CD34+90+ cell dose does not predict early engraftment of autologous blood stem cells as well as the total CD34+ cell dose

CD90 or Thy-1 is an antigen co-expressed with CD34+ on putative immature hematopoietic stem cells. Peak mobilization of CD34+90+ cells into the blood occurs a few days earlier than peak mobilization of total CD34+ cells. Because it is not known which cell type best correlates with engraftment, the optimal timing of apheresis remains unclear. The purpose of the study was to determine if the CD34+90+ cell dose predicts engraftment of autologous blood stem cells independent of the total CD34+ cell dose/kg, the dose of other CD34+ cell subsets (CD34+33-, CD34+38-, CD34+41+), or various clinical factors. Data were analyzed on 125 consecutive patients ranging in age from 19 to 66 years (median 46) who underwent autologous blood stem cell transplantation (ABSCT) for breast cancer (54), lymphoma (59), or other malignancies (12). By univariate analysis, neutrophil (> or = 0.5 x 10(9)/l) and platelet (> or = 20 x 10(9)/l or > or = 100 x 10(9)/l) engraftment correlated better with the total CD34+ cell dose than with the CD34+90+ cell subset. Using Cox proportional hazards models, factors independently associated with both neutrophil engraftment (> or = 0.5 x 10(9)/l) and platelet engraftment (> or = 20 x 10(9)/l and > or = 100 x 10(9)/l) were higher total CD34+ dose/kg and high-dose regimen (melphalan-containing slower than other regimens). In conclusion, the total CD34+ dose/kg was a better predictor of hematopoietic engraftment following ABSCT than the dose of any CD34+ subset, including CD34+90+ cells. Apheresis should continue to be timed according to peak CD34+ levels.     

Transplantation of umbilical cord blood after myeloablative therapy: analysis of engraftment.

The possibility that umbilical cord and placental blood from an HLA-identical sibling might produce stable donor-derived lymphohematopoietic engraftment was tested in a patient with juvenile chronic myelogenous leukemia (JCML). After conditioning with high-dose busulfan and cyclophosphamide, cryopreserved umbilical cord blood, containing 0.5 x 10(8) nucleated cells/kg and 2.7 x 10(4) colony forming units-granulocyte, macrophage (CFU-GM)/kg, was infused. A leukocyte count greater than 1,000/microL, absolute neutrophil count (ANC) greater than 500/microL, and platelet count greater than 20,000/microL (untransfused) were observed on days 39, 39, and 47 after transplantation, respectively. Donor cell engraftment was documented in the peripheral blood and bone marrow by cytogenetic analysis, restriction fragment length polymorphism (RFLP), and polymerase chain reaction (PCR) as early as day 21. Furthermore, the donor origin of each lymphohematopoietic lineage (ie, CD5+ T cells, CD19/20+ B cells, CFU-GM, and burst-forming unit-erythrocyte [BFU-E]) was confirmed. On day 200, assays of the peripheral blood and bone marrow showed an abnormal proliferation of CFU-GM at low seeding densities in the absence of exogenous growth factors, as well as a hypersensitivity to granulocyte-macrophage colony-stimulating factor (GM-CSF), both pathophysiologic characteristics of JCML. Recurrent disease was confirmed histologically on day 225. Together, these results demonstrate that umbilical cord blood contains sufficient numbers of hematopoietic stem cells necessary for the engraftment of leukemia patients treated with myeloablative therapy and that the detection of "spontaneous" CFU-GM and hypersensitivity to GM-CSF after treatment is a marker of residual or recurrent disease in patients with JCML.     

Multidisciplinary therapy including high-dose chemotherapy followed by peripheral blood stem cell transplantation for invasive thymoma

We describe two patients with invasive thymomas who responded to high-dose chemotherapy followed by peripheral blood stem cell transplantation (PBSCT) combined with surgery and radiotherapy. The first patient was a 42-year-old man admitted to the hospital with chest pain, and the second patient was a 45-year-old man admitted with myasthenia gravis. Both patients had nonresectable thymomas (stage IVa) because of invasion of the aorta, pulmonary artery, or both, and dissemination to the pericardium. They initially received two cycles of chemotherapy consisting of adriamycin (40 mg/m(2), day 1), cisplatin (50 mg/m(2), day 1), vincristine (0.6 mg/m(2), day 3), and cyclophosphamide (700 mg/m(2), day 4) at 3-week intervals. Four weeks later, they were administered high-dose etoposide (300 mg/m(2), days 1 to 5) followed by granulocyte colony-stimulating factor (G-CSF) [50 micro g/m(2)/d] subcutaneously to mobilize stem cells into the blood. After two additional cycles of adriamycin, cisplatin, vincristine, and cyclophosphamide (ADOC), the patients received high-dose ifosfamide (1.5 g/m(2), days 1 to 4), carboplatin (400 mg/m(2), days 3 to 5), and etoposide (200 mg/m(2), days 1 to 5) followed by PBSCT. They were administered G-CSF (50 micro g/m(2)/d) after PBSCT, with subsequent rapid recovery of neutrophil and platelet level. The tumors shrank remarkably, and could be excised completely in both patients. Postoperatively, 50 Gy of irradiation was administered. Disease-free status has been maintained for 5 years in the first patient and 2 years in the second patient. Our findings suggest that high-dose ifosfamide, carboplatin, and etoposide followed by PBSCT in combination with an ADOC regimen, surgery, and radiotherapy is very effective and well tolerated in patients with advanced nonresectable thymoma.     

Cytotoxic drug and cytotoxic drug/G-CSF mobilization of peripheral blood stem cells and their use for autografting.

We analysed 99 courses of leukapheresis after the use of cytotoxic drugs or cytotoxic drugs plus G-CSF (cytotoxic/G-CSF) to mobilize peripheral blood stem cells (PBSC) in 68 patients with hematologic or solid malignancies. Mean yields of granulocyte-macrophage progenitor cells (CFU-GM) with cytotoxic/G-CSF mobilization were significantly higher than those with cytotoxic mobilization (18.6 vs 8.40 x 10(4)/kg). The optimal timing of collection was different between these two mobilizations; the mean number of days to a peak level of circulating CFU-GM after cytotoxic/G-CSF mobilization was less than that after cytotoxic mobilization (24.2 vs 27.7 days). The leukocyte level on the day of peak CFU-GM was significantly higher in cytotoxic/G-CSF mobilization than that in cytotoxic mobilization (mean 12.8 vs 2.7 x 10(9)/l), whereas the platelet level was not different (mean 132 vs 125 x 10(9)/l). Increasing patient age was not a major adverse factor for PBSC collection. Synchronous recovery of both leukocytes and platelets was critical for achieving a high CFU-GM yield in these two mobilizations. Following PBSC autotransplantation, the rate of trilineage hematologic reconstitution showed a significant correlation with the infused dose of CFU-GM, whether they were collected with cytotoxic or cytotoxic/G-CSF mobilization. These results suggest that G-CSF can expand the PBSC pool and that CFU-GM yield after cytotoxic/G-CSF mobilization may predict trilineage hemopoietic reconstitution after ABSCT, as well as cytotoxic mobilization.     

Plastic-adherent progenitor cells in mobilized peripheral blood progenitor cell collections

The use of peripheral blood progenitor cells (PBPC) to reconstitute hematopoiesis after high-dose chemoradiotherapy is now commonplace in the treatment of malignancies. Attempts to characterize these cells have concentrated primarily on their phenotype and their content of clonogenic colony-forming cells (CFC). We have used a plastic-adherent delta (P delta) assay system to evaluate the quantity and quality of more primitive cells in addition to the conventional measurements of CFC and CD34-positive cells. The leukapheresis products from 20 patients mobilized using cyclophosphamide (Cy) and granulocyte colony- stimulating factor (G-CSF) were examined for progenitor cell content. The mean number of mononuclear cells (MNC), colony-forming units- granulocyte/macrophage (CFU-GM), and CD34-positive cells from two leukaphereses per patients were 7.9 x 10(8)/kg, 47.3 x 10(4)/kg, and 10.5 x 10(6)/kg, respectively. The mean number of P delta progenitors was 9.3 x 10(4)/kg. Limiting dilution analyses showed the frequency of P delta progenitors in PBPC to be between 1 and 5.3 per 10(5) MNC and that each P delta progenitor has the proliferative capability to generate an overall mean of 4.5 CFU-GM. Of the 20 patients, 16 underwent autografting with PBPC alone. Fifteen patients engrafted neutrophils and platelets within 16 days. One patient had delayed engraftment associated with inadequate etoposide clearance. Statistical analysis showed a strong correlation between numbers of CFU-GM and CD34 positivity. The numbers of plastic-adherent P delta progenitor cells did not correlate with CFU-GM or CD34-positive cells. We conclude that the plastic-adherent P delta progenitor cell assay is capable of measuring primitive hematopoietic cells and that it may be useful for the investigation of primitive progenitors in PBPC harvests.     

Collection of peripheral blood stem cells mobilized by high-dose Ara-C plus VP-16 or aclarubicin followed by recombinant human granulocyte-colony stimulating factor.

We developed an effective method for harvesting large numbers of peripheral blood stem cells (PBSC) for use in autotransplantation. Twenty patients with hematological malignancies were treated with high doses of Ara-C (12 g/m2) and VP-16/aclarubicin followed by administration of rhG-CSF (50 micrograms/m2). The optimal time for starting PBSC collection was determined by monitoring the CD34-positive stem cells in blood using immunomagnetic beads. PBSC were collected with a CS-3000 blood cell separator. A total blood volume between 7000 and 9000 ml was processed in each apheresis. Under these conditions, a total of 64 apheresis procedures was performed in the 20 patients. The mean numbers of mononuclear cells and of CFU-GM harvested per apheresis were 4.1 x 10(8)/kg and 110 x 10(4)/kg, respectively. A number of CFU-GM sufficient for engraftment (> 30 x 10(4)/kg) could be harvested by a single apheresis in 15 of the 20 patients. So far, 11 patients have been transplanted with PBSC and obtained rapid hematopoietic recovery. The median time to recover neutrophils more than 0.5 x 10(9)/l was 10 days, and that for platelets 50 x 10(9)/l was 11 days. This method for harvesting large numbers of PBSC allows safer autotransplantation in patients with chemoradiosensitive tumors, and is applicable to older patients.     

Factors affecting blood stem cell collections following high-dose cyclophosphamide mobilization in lymphoma, myeloma and solid tumors.

Sixty patients with malignancy were enrolled in a study of high-dose chemotherapy and peripheral blood stem cell transplantation (PBSCT). Stem cells were harvested prior to PBSCT using high-dose cyclophosphamide (CY) mobilization (4 or 7 g/m2) with collection of a median of 4.6 x 10(8)/kg mononuclear cells (range 0.2-9.5) and 21.6 x 10(4)/kg colony forming unit-granulocyte/macrophage (CFU-GM) (range 0.1-220). Forty-seven patients were mobilized once, 11 required two cycles and two required three cycles. Eight patients (13%) failed to reach the optimum CFU-GM target (greater than 15 x 10(4)/kg) following CY mobilization. A number of factors identified those patients who were likely to achieve optimum CFU-GM collections with CY mobilization. These included the use of the higher CY mobilization dose, a longer interval from last chemotherapy cycle to mobilization, and a higher premobilization bone marrow CFU-GM level. Patient's age, the degree of bone marrow infiltration, the nature of disease or the number of pre-mobilization chemotherapeutic cycles did not affect the ability to collect optimum CFU-GM numbers. Whilst the mobilization procedure was associated with moderate non-hematologic toxicity, significant hematological morbidity was observed primarily in patients mobilized using the 7 g/m2 dose. Refinements to the protocol, in particular the use of hematopoietic growth factors, are currently under investigation.     

Cyclophosphamide, etoposide and carboplatine plus non-cryopreserved autologous peripheral blood stem cell transplantation rescue for patients with refractory or relapsed non-Hodgkin's lymphomas

A simplified schedule of high-dose chemotherapy consisting of cyclophosphamide (60 mg/kg/day for 2 days), etoposide (15 mg/kg/day for 2 days) and carboplatine (400 mg/m(2)/day for 2 days), together with autologous non-cryopreserved peripheral blood stem cells was used for treatment of relapsed (29 patients) and refractory (three patients) patients with non-Hodgkin's lymphoma (NHL). The use of such granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood stem cells (PBSC) after high-dose myeloablative therapy resulted in a rapid, complete and sustained hematopoietic recovery. The median time to achieve an absolute neutrophil count greater than 0.5 x 10(9)/l was 12 days (range 8-17 days). The median time to self-sustained platelet count greater than 20 x 10(9)/l was 14 days (range 7-19 days). Fifteen of the 32 patients (49%) were alive and disease free at a median follow-up of 18 months (range 10-96 months) for all surviving patients. The estimated 2-year overall survival (OS) and disease free survival (DFS) for all patients were 50 and 43%, respectively. Twelve patients died of relapse or progressive disease, two patients died of infection and one patient died of cardiac cause. The median time to relapse was 12 months (5-27) from PBSC infusion. High-dose chemotherapy with short-duration chemotherapy and non-cryopreserved bone marrow (BM) is an effective and safe treatment modality for patients with relapsed or resistant NHL.     

Escalating sequential high-dose carboplatin and etoposide with autologous marrow support in children with relapsed solid tumors.

Thirty patients with relapsed pediatric solid tumors received high-dose carboplatin and etoposide with autologous marrow support in a dose-escalation trial. These patients had received extensive prior treatment, which included both cisplatin and etoposide in 25 cases. Six patient cohorts received carboplatin in doses of 1200-2100 mg/m2 and etoposide in doses of 960-1500 mg/m2. All courses were associated with severe neutropenia and thrombocytopenia. The median times from bone marrow infusion to granulocyte recovery (> 0.5 x 10(9)/l) and platelet recovery (> 50 x 10(9)/l) were 33 and 28 days, respectively, with similar findings for all dosage levels. The frequency of non-hematologic toxicities was generally low, although hyponatremia (Na+ < 129 mEq/l) was seen in one-third of the courses. Hepatoxicity was dose-limiting and was significantly associated with the cumulative prior cisplatin dose (p = 0.006). There were four toxic deaths (CNS hemorrhage, alfa-streptococcal sepsis, Candida sepsis, and enterocolitis). Eleven patients received a second course of therapy; toxicity profiles and times to hematologic recovery were similar for the two courses. Clinical responses were observed at all dosage levels. Eleven of 26 evaluable patients achieved a clinical response (one complete, 10 partial). The majority of responses were in patients with neuroblastoma (six of 16) or Hodgkin's disease (two of three). For phase II clinical trials, we recommend dosages of 2100 mg/m2 of carboplatin and 1500 mg/m2 of etoposide for children with prior cumulative cisplatin exposure < 960 mg/m2. This carboplatin dose represents a three- to four-fold increase over pediatric doses tolerated without bone marrow support.     

Factors influencing hematopoietic recovery after autologous blood stem cell transplantation in patients with acute myeloblastic leukemia and with non-myeloid malignancies

Factors influencing hematopoietic recovery (HR) after autologous blood stem cell transplantation (ABSCT) were analyzed in 73 patients with various non-myeloid malignancies (NMM), and in 58 patients with acute myeloblastic leukemia (AML). Peripheral blood stem cells were collected following mobilization with chemotherapy, granulocyte colony-stimulating factor (G-CSF), or chemotherapy plus G-CSF. The conditioning regimen used consisted of either chemotherapy alone (112 cases) or chemotherapy plus total body irradiation (19 cases). The median number of colony-forming units granulocyte-macrophage (CFU-GM) was similar in both groups of patients, with the median number of CD34(+) cells infused being higher in the AML group (5.4 vs 4 x 10(6)/kg; P = 0.03). Median time neutrophils >0.5 x 10(9)/l was 13 days in both groups, and median time to a platelet count >20 x 10(9)/l was longer in AML patients (14 vs 12 days; P = 0.01). In multivariate analysis, the only factors affecting neutrophil recovery in the NMM group were the CD34+ cell number (continuous model) and the CFU-GM dose (categorized model) infused, whereas for platelet recovery, previous chemotherapy also remained significant. In the AML group, the only factors significantly affecting the speed of neutrophil recovery were dose of CD34+ cells administered and the patient's age. As for platelet recovery, only the progenitor dose administered remained significant. In the NMM group, the most discriminating cut-off values for a rapid neutrophil and platelet recovery were 1.5 x 10(6) and 2.5 x 10(6) CD34+ cells/kg, respectively, and for AML patients these figures were 1.5 x 10(6) and 4 x 10(6) CD34+ cells/kg, respectively. Our results confirm the slower HR after ABSCT in AML, and highlight the importance of progenitor cell dose in accelerating HR after ABSCT.     

Ideal body weight correlates better with engraftment after PBSC autograft than actual body weight, but is under-estimated in myeloma patients possibly due to disease-related height loss

Stem cell dose is important in determining rate of engraftment following autograft. We show closer correlation with haematopoietic reconstitution when the CD34+ cell dose is calculated using ideal (IBW) rather than actual (ABW) body weight in 218 patients receiving peripheral blood stem cell (PBSC) autograft for haematological malignancy. ABW was 21% greater than IBW thus the median CD34+ dose of 5.0 x 10(6)/kg (ABW) rose to 6.1 x 10(6)/kg when calculated by IBW. Neutrophils reached 0.5 x 10(9)/l in 11 days (range 8-21), while platelets reached 20 x 10(9)/l unsupported in 12 days (range 7-38). For both neutrophil and platelet engraftment, a greater inverse correlation was seen when IBW was used to calculate stem cell dose (r2=0.082 vs r2=0.104 for neutrophils and r2=0.085 vs r2=0.135 for platelets). Those non-myeloma patients who failed to achieve a CD34+ dose of 4 x 10(6) cells/kg by ABW but did so by IBW achieved neutrophil and platelet engraftment not significantly different from those who achieved that stem cell dose by both methods. This was not confirmed in patients treated for myeloma, possibly owing to inaccurate IBW in patients with skeletal height loss. We confirm that calculation of CD34+ cell dose by IBW safely predicts engraftment for patients with haematological malignancies other than myeloma undergoing PBSC autograft.     

ESHAP plus G-CSF as an effective peripheral blood progenitor cell mobilization regimen in pretreated non-Hodgkin's lymphoma: comparison with high-dose cyclophosphamide plus G-CSF

The ESHAP (etoposide, methylprednisolone, high-dose cytarabine, and cisplatin) regimen has been shown to be effective as an active salvage therapy for lymphoma. Mobilizing stem cells following ESHAP should decrease time to transplantation by making separate mobilizing chemotherapy (MC) unnecessary, while controlling a patient's lymphoma. We therefore assessed the mobilization potential of ESHAP plus G-CSF in 26 patients (ESHAP group) with non-Hodgkin's lymphoma (NHL) and compared these results with those of 24 patients with NHL who received high-dose (4 g/m2l) cyclophosphamide (HDCY) as MC (HDCY group). The age, sex, and radiotherapy to the axial skeleton were well matched between groups, but the number of patients with poor mobilization predictors was higher in the ESHAP group. Significantly higher numbers of CD34+ cells (x 10(6)/kg) (17.1+/-18.8 vs 5.8+/-5.0, P=0.03) and apheresis day 1 CD34+ cells (x 10(6)/kg) (5.5+/-6.6 vs 1.7+/-2.0, P=0.014) were collected from the ESHAP group than from the HDCY group, and the number of patients who achieved an optimal CD34+ cell target of 5 x 10(6)/kg was higher in the ESHAP group (81 vs 50%, P=0.022). Log-rank test revealed that time to target peripheral blood progenitor cell collection (> or =5 x 10(6)/kg) was shorter in the ESHAP group (P=0.007). These results indicate that ESHAP plus G-CSF is an excellent mobilization regimen in patients with relapsed and poor-risk aggressive NHL.     

Very large amounts of peripheral blood progenitor cells eliminate severe thrombocytopenia after high-dose melphalan in advanced breast cancer patients

We analyzed the relationship between the reinfusion of large or very large amounts of peripheral blood progenitor cells (PBPC) and hematologic toxicity in twenty-one advanced breast cancer patients subjected to a myeloablative dose of melphalan at the end of a high-dose sequential chemotherapy (HDSC) program. We also evaluated the influence of the white blood cell (WBC) count to predict an optimal PBPC harvest after high-dose chemotherapy and growth factor priming. Twenty-one patients with high-risk or metastatic breast cancer sequentially received: high-dose cyclophosphamide (HD-Cy) and G-CSF followed by PBPC harvest, HD-methotrexate plus vincristine, HD-doxorubicin, cisplatin and finally HD-melphalan 200 mg/m2 (HD-L-PAM) followed by PBPC reinfusion. No growth factor was administered after HD-L-PAM. CD34+ cytofluorimetric analysis, WBC count and clonogenic assays were employed to monitor circulating cells and to analyze the PBPC harvest. Correlation between different PBPC doses and hematologic toxicity as well as leukocyte and platelet recovery time was attempted. Patients received a median number of 16 (4-25.1) x 10(6)/kg CD34+ cells, 81.3 (30.8-228) x 10(4)/kg CFU-GM and 4.2 (1.3-7.3) x 10(8)/kg nucleated cells (NC) after HD-L-PAM. The number of days with fewer than 1 x 10(9)/l leukocytes and 20 x 10(9)/l platelets were 6 (range 4-9) and 0 (range 0-3), respectively. The CD34+ cell dose significantly correlated with both platelet count nadir (r = 0.73) and time to 50 x 10(9)/l platelets (r = 0.7), but did not correlate with time to reach more than 1 x 10(9)/l WBC count (r = 0.2). In particular, we found that in 12 patients given very large amounts of CD34+ cells, ranging between 15.8 and 25. 1 x 10(6)/kg (V-LA-CD34+), the platelet nadir count never fell below 20 x 10(9)/l and platelet transfusions were not required. Conversely, nine patients who received only large amounts of CD34+ cells, ranging between 4 and 12 x 10(6)/kg (LA-CD34+), experienced a platelet nadir lower than 20 x 10(9)/l and required 2 days (range 1-4) to achieve independence from platelet transfusions (P = 0.001 and P = 0. 0005). The requirement for packed red blood cells (RBC) was 1.5 vs 3 units in the V-LA-CD34+ and LA-CD34+ groups respectively (P = 0.063). The analysis of 44 PBPC collections demonstrated that 29 aphereses performed with a WBC count <20 x 10(9)/l yielded a mean of 312 +/- 43 x 10(6) CD34+ cells and 1831 +/- 201 x 10(4) CFU-GM, whereas 15 collections performed with WBC count >20 x 10(9)/l yielded 553 +/- 64 x 10(6) CD34+ cells and 3190 +/- 432 x 10(4) CFU-GM (P = 0.004). In conclusion, our data suggests that V-LA-CD34+ eliminates severe thrombocytopenia and platelet transfusion requirements in breast cancer patients subjected to HD-L-PAM, and higher PBPC collections seems to coincide with WBC count higher than 20 x 10(9)/l after HD-Cy and G-CSF mobilization. These results justify a prospective study to establish whether large doses of CD34+ cells result in significant clinical benefits.     

Haematopoietic stem cell transplantation for active systemic lupus erythematosus.

OBJECTIVE: For patients with systemic lupus erythematosus (SLE) who are at risk of disease-related mortality, we have initiated a protocol of intensive immunosuppression and haematopoietic stem cell support. The first patient enrolled in this study was in the midst of a lupus flare manifest by nephritis and rapidly declining renal function, uncontrolled hypertension, immune-mediated cytopenias, and serositis characterized by a large pericardial effusion and abdominal pain. Antinuclear antibody (ANA), anti-double-stranded (ds) DNA and complement were abnormal. This patient is now more than 1 yr post-stem cell transplant and is taking no immunosuppressive medication. Her serologies are normal, effusions have resolved, blood pressure is normal and renal function is markedly improved. The clinical and serological course of this patient is summarized here. METHODS: Autologous haematopoietic stem cells (HSC) were mobilized with cyclophosphamide (2.0 g/m2) and granulocyte colony-stimulating factor (G-CSF) (10 microg/kg/day). Stem cells were enriched ex vivo using CD34-positive immunoselection and reinfused after immunosuppression with cyclophosphamide (200 mg/kg) and antithymocyte globulin (ATG) (90 mg/kg). RESULTS: White blood cell engraftment with an absolute neutrophil count (ANC) of >500/microl (0.5 x 10(9)/l) and platelet engraftment with a non-transfused platelet count of >20000/microl (20 x 10(9)/l) occurred on day 10 and 14, respectively. Therapy was complicated by a cell lysis-like effect with hyperphosphataemia, hyperuricaemia, normal anion gap metabolic acidosis and transient exacerbation of renal insufficiency. CONCLUSION: This is the first autologous T-cell-depleted haematopoietic stem cell transplantation performed to treat lupus in an active flare. This patient has, for the first time since discase onset (13 yr ago), entered a complete clinical and serological remission which persists at >1 yr of follow-up. The durability of this remission is unknown.     

Autologous peripheral blood stem cell transplantation after high dose therapy in patients with advanced lymphomas.

Thirty-eight patients with refractory or relapsed non-Hodgkin's lymphoma (19 patients) or Hodgkin's disease (19 patients) were treated with salvage therapy. The peripheral stem cell collection was performed during hematologic recovery after myeloablative chemotherapy. In eight patients with Hodgkin's disease the number of CFU-GM collected was less than 0.5 x 10(4)/kg and these patients were excluded for stem cell transplantation. In the remaining 30 patients, a median of 4 x 10(4) CFU-GM/kg was collected (range 0.8-100 x 10(4)/kg) by three leukaphereses in 25 patients and six to 11 leukaphereses in five patients. Conditioning regimens were CBV (eight), BEAM (six), BEAC (10) and cyclophosphamide + total body irradiation (TBI) (six). Without TBI, the mean time for reaching a granulocyte count greater than 0.5 x 10(9)/l was 18 days and for a platelet count greater than 50 x 10(9)/l was 19 days in 23 out of 24 patients. With TBI, in five patients the mean time for reaching a granulocyte count greater tahn 0.5 x 10(9)/l was 37 days and for a platelet count greater than 50 x 10(9)/l was greater than 100 days. Complications were minor. There was only one toxic death. The outcome in these patients was similar to that observed in patients who received autologous bone marrow transplantation for advanced lymphomas. In conclusion, we observed good hematologic recovery except when TBI was used in the conditioning regimen.     

Myeloid progenitor cells (CFU-GM) predict engraftment kinetics in autologous transplantation in children

In autologous stem cell transplantation the duration of aplasia may be particularly long. We studied 27 children with a median age of 5 years (1-16), who received 31 autologous grafts, seven of them receiving both bone marrow and peripheral stem cells. Five were transplanted with blood derived stem cells only. The median number of nucleated cells (NC) grafted was 1.04 x 10(8)/kg body weight (range 0.09-6.72). The median number of granulocyte-macrophage progenitors (CFU-GM) transfused was 0.66 x 10(4)/kg body weight (range 0-11.8). The numbers of NC correlated with the CFU-GM numbers (p less than 0.001), and were inversely correlated with time to recover 1 x 10(9)/l leukocytes and 0.5 x 10(9)/l granulocytes (p less than 0.01), as well as with the appearance of reticulocytes (p less than 0.05). Moreover, the logarithm of the CFU-GM numbers transfused was linearly correlated with the time to recover 1 x 10(9)/l leukocytes and 0.5 x 10(9)/l granulocytes (p less than 0.001), respectively. There also existed an inverse correlation with the first appearance of reticulocytes in the peripheral blood (p less than 0.01). No correlation could be detected with the duration of platelet transfusion dependence. Based on our findings a prediction of time to recover leukocytes, granulocytes and reticulocytes is feasible before grafting with autologous bone marrow and peripheral stem cells.     

Haemopoietic reconstitution after autologous blood stem cell transplantation in patients with malignancies: a multicentre retrospective study

A retrospective study was undertaken to evaluate the efficacy of autologous blood stem cell transplantation (ABSCT) in terms of haemopoietic reconstitution after ablative chemotherapy or chemo-radiotherapy. 55 patients with malignancies, observed in four Italian institutions from January 1987 to June 1991, were eligible for evaluation. This series included 19 non-Hodgkin's lymphoma, 11 multiple myeloma, nine ovarian cancer, seven Hodgkin's disease, seven non-lymphocytic leukaemia, one acute lymphoblastic leukaemia, one neuroblastoma. 522 PBSC collections were performed on 55 patients. Following ABSCT, the rate of engraftment was positively related to the dose of CFU-GM infused and negatively to the presence of bone marrow involvement at conditioning. 48 patients out of 55 transplanted (87%) had rapid, complete and sustained engraftment. Three patients (5%) died of transplant-related complications. Considering that 60% of the patients in this series were in partial remission or in progressive disease at the time of ABSCT, we conclude that ABSCT is a safe approach for the use of ablative conditioning therapy in patients with a wide scope of malignancies, provided that a large number of CFU-GM have been collected after mobilizing treatment.     

Autologous peripheral blood stem cell transplantation for acute leukaemias.

Initial interest in autologous blood stem cell transplants (ABSCT) in acute myeloid leukaemia (AML) was based on the postulate that there might be less malignant contamination than with bone marrow transplants. Although this remains presently uncertain, other advantages of ABSCT, such as a rapid haematopoietic recovery, were immediately recognized. In pilot studies, peripheral blood stem cells (PBSC) were collected after standard induction and consolidation courses of chemotherapy. The actuarial disease-free survival (DFS) and relapse rates (RR) at 2-3 years ranged from 28 to 39% and 57 to 60%, respectively. Recently, PBSC collection after high-dose cytarabine, with or without G-CSF, has been associated with DFS ranging from 47 to 57%. Thus, the timing of stem cell collection seems to be crucial in AML and it should be performed following an efficient in vivo purging but before the haematopoietic reserve is exhausted. Clinical results with ABSCT are similar to those seen after autologous bone marrow transplant (ABMT), although important issues such as potential contamination of stem cell collections and optimal timing of PBSC harvest remain to be clarified. Prospective randomized studies comparing ABMT and ABSCT are needed for definitive evaluation of the role of the source of stem cells in AML treatment.     

Effect of peripheral blood progenitor cell dose on hematopoietic recovery: identification of minimal progenitor cell requirements for rapid engraftment

Repeated high-dose chemotherapy (HDC) with stem cell support is advocated for curative treatment of epithelial ovarian cancer patients, requiring large quantities of progenitor cell harvest. Although the switchover to peripheral blood stem cell transplantation has generally made possible the harvest of large quantities of progenitor cells, the minimum threshold is still pertinent for planning the safe conduct of HDC. However, as the minimum threshold for safe peripheral blood stem cell transplantation (PBSCT) is not yet established, this study was designed to clarify the minimum amount of progenitor cells required for prompt recovery of hematopoietic. Retrospective analysis was performed on 52 HDCs administered in 37 ovarian cancer patients. After autologous bone marrow aspiration (10 patients) or peripheral blood stem cell harvest (27 patients), colony-forming unit granulocyte macrophage (CFU-GM) were enumerated prior to cryopreservation. Numbers of CFU-GM were again calculated before reinfusion and the patients were divided into eight groups: 0.13-<0.4, 0.4-<0.7, 0.7-<1.0, 1.0-<3.5, 3.5-<5.0, 5.0-<10.0, 10.0-<20.0 and >20.0 (x 10(5)/kg). The minimum CFU-GM threshold (x 10(5)/kg) was found to be 1.0-<3.5 for platelets and 3.5-<5.0 for white blood cells. Higher infusion doses did not lead to significant benefits in hematopoietic reconstruction. These results indicate that preservation of a minimum of 7-10 x 10(5)/kg CFU-GM is recommended for the safe conduct of tandem HDCs.     

Successful treatment of relapsed T-cell non-Hodgkin's lymphoma with allogeneic peripheral blood stem cell transplantation with double conditioning.

We report a patient with T-cell non-Hodgkin's lymphoma (NHL) who relapsed after treatment with relatively intensive third-generation chemotherapy, VACOP-B, and who was safely and effectively treated with allogeneic peripheral blood stem cell transplantation (allo PBSCT) with double conditioning. The first conditioning consisted of carboplatin and etoposide. Twenty-one days later, the second conditioning was performed with cytosine arabinoside, cyclophosphamide, and total body irradiation (AraC/Cy/TBI). Between the periods of the first and second conditioning, autologous (auto) PBSCT (4.4 x 10(5) colony-forming units granulocyte/macrophage (CFU-GM)/kg, 3.8 x 10(6) CD34+ cells/kg) was performed to rescue marrow aplasia after the first conditioning. After the second conditioning, allo PBSCT (2.1 x 10(5) CFU-GM/kg, 8.2 x 10(6) CD34+ cells/kg) was performed from a human leukocyte antigen-identical sibling. Marrow reconstitution after allo PBSCT was rapid. Grade I acute graft-vs.-host disease (GVHD) involving skin and chronic GVHD on the eye was observed. No severe transplantation-related complications occurred. With a follow-up of 22 months after allogeneic PBSCT, the patient is alive without evidence of the disease. This case shows that allo PBSCT with intensive double conditioning may become a new treatment strategy to achieve long-term disease-free survival for young NHL patients of resistant relapse with a great deal of tumor burden and invasion of lymphoma cells in bone marrow.