Effects of short-term administration of G-CSF (filgrastim) on bone marrow progenitor cells: analysis of serial marrow samples from normal donors

To determine the effect of G-CSF administration on both the total number of CD34+ cells and the primitive CD34+ subsets in bone marrow (BM), we have analyzed BM samples serially obtained from 10 normal donors in steady-state and during G-CSF treatment. Filgrastim was administered subcutaneously at a dosage of 10 microg/kg/day (n = 7) or 10 microg/kg/12 h (n = 3) for 4 consecutive days. Peripheral blood sampling and BM aspirates were performed on day 1 (just before G-CSF administration), day 3 (after 2 days of G-CSF), and day 5 (after 4 days of G-CSF). During G-CSF administration, a significant increase in the total number of BM nucleated cells was observed. The percentage (range) of CD34+ cells decreased in BM from a median of 0.88 (0.47-1.44) on day 1 to 0.57 (0.32-1.87), and to 0.42 (0.16-0.87) on days 3 and 5, respectively. We observed a slight increase in the total number of BM CD34+ cells on day 3 (0.66 x 10(9)/l (0.13-0.77)), and a decrease on day 5 (0.23 x 10(9)/l (0.06-1.23)) as compared with steady-state (0.40 x 10(9)/l (0.06-1.68)). The proportion of primitive BM hematopoietic progenitor cells (CD34+CD38-, CD34+HLA-DR-, CD34+CD117-) decreased during G-CSF administration. In parallel, a significant increase in the total number of CD34+ cells in peripheral blood was observed, achieving the maximum value on day 5. These results suggest that in normal subjects the administration of G-CSF for 5 days may reduce the number of progenitor cells in BM, particularly the most primitive ones.

Chronic graft-versus-host disease after allogeneic peripheral blood progenitor cell or bone marrow transplantation from matched related donors. A case-control study. Spanish Group of Allo-PBT

We retrospectively compared the incidence and clinical characteristics of cGVHD in 37 allo-PBT recipients transplanted between July 1994 and October 1996 and 37 historical control allo-BMT recipients in a case-control study. All patients received a first unmanipulated transplant, graft from an HLA-identical sibling donor, with CsA-MTX GVHD prophylaxis and survived more than 100 days after transplant. PBT and BMT groups were well matched for age, grade of acute GVHD, male patients grafted from female donors, and phase of disease. The median CD34+ and CD3+ cell numbers infused in the PBT group were 5.2 x 10(6)/kg and 307 x 10(6)/kg, respectively. The median time to an ANC greater than 0.5 x 10(9)/l was 16 days (range 11-22) after PBT and 22 days (range 14-36) after BMT (P < 0.001). The median time to a platelet count greater than 20 x 10(9)/l was 15 days (range 6-43) after PBT and 28 days (range 12-68) after BMT (P < 0.001). Median follow-up was 12.3 months (range 5.4-30.3) and 58.7 months (range 4-122.3), for patients receiving PBT and BMT, respectively. Seventeen out of 37 (46%) PBT recipients, vs nine out of 37 (24%) BM recipients developed cGVHD. Actuarial probability of cGVHD at 1 year was 59% (95% CI, 39-79) in the PBT group vs 27% (95% CI, 12-42) in the BM group (P = 0.01). Cumulative incidence estimate of cGVHD was 51% and 25%, for patients receiving PBT and BMT respectively (P = 0.03). Clinical characteristics of cGVHD and response to therapy were similar in both groups, except for a higher incidence of de novo cGVHD in the PBT group. Our results suggest that as compared with BMT, PBT may result in an increased incidence of cGVHD.

Allogeneic transplantation of selected CD34+ cells from peripheral blood: experience of 62 cases using immunoadsorption or immunomagnetic technique. Spanish Group of Allo-PBT

The objective of this study was to analyze CD34+ cell recovery and T cell depletion (TCD) achieved in CD34+ cell grafts using either immunoadsorption or immunomagnetic methods applied to leukapheresis products from healthy donors. We also wanted to determine the kinetics of engraftment and incidence and severity of graft-versus-host disease (GVHD) after allogeneic transplantation of selected CD34+ cells. HLA-identical sibling donors received G-CSF. After leukapheresis, peripheral blood progenitor cells were selected using immunoadsorption (Ceprate SC) (n = 38) or immunomagnetic (Isolex 300) (n = 24) methods. Sixty-two patients, with a median age of 42 years (range 17-60) diagnosed with hematological malignancies were conditioned with either cyclophosphamide and total body irradiation (n = 43) or busulphan and cyclophosphamide (n = 19). GVHD prophylaxis consisted of cyclosporin A (CsA) and prednisone (n = 48), CsA alone (n = 11) and CsA and methotrexate (n = 3). The median yield and purity of CD34+ cells after the procedure was 65 and 66% with immunoadsorption, and 48 and 86% with immunomagnetic method, respectively. The median number (range) of CD34+ cells infused into the patients was 3.5 x 10(6)/kg (1-9.6). The median number (range) of CD3+ cells administered was 0.4 x 10(6)/kg (0.01-2) using immunoadsorption and 0.14 x 10(6)/kg (0.03-2.5) using immunomagnetic methods. Neutrophil recovery >500 and >1000/microl was achieved at a median (range) of 13 days (8-22) and 14 days (9-31), respectively. Platelets recovered to >20000 and >50000/microl at a median (range) of 13 days (0-128) and 18 days (0-180), respectively. Two patients developed graft failure. Acute GVHD in patients at risk was clinical grade 0 (n = 43), I (n = 8), II (n = 4) and III (n = 1). No patient developed acute GVHD grade IV. Chronic GVHD was limited in two cases and extensive in four cases. The actuarial probability of acute GVHD II-IV was 10% (95% CI, 1-19%), and of extensive chronic GVHD was 12% (95% CI, 11-13%). The cumulative incidence of transplant-related mortality was 12.6%, and this figure was 9% at 6 months. In conclusion, with the immunomagnetic procedure, a lower recovery and higher purity of CD34+ cells, and stronger TCD is obtained as compared to immunoadsorption (P = 0.008, P < 0.0001 and P = 0.0002, respectively). Our results also indicate that allogeneic transplantation of selected CD34+ cells is associated with a very rapid engraftment and with a low incidence of severe GVHD.

Allogeneic transplantation of purified CD34+ cells from peripheral blood: Spanish experience of 62 cases. Spanish Group of allo-PBT

This report summarizes the Spanish experience of 62 cases of allogeneic transplantation of purified CD34+ cells from peripheral blood. HLA-identical sibling donors received G-CSF. After leukapheresis, peripheral blood progenitor cells were purified using one of two methods: Ceprate (n = 38), or Isolex 300 (n = 24). Sixty-two patients median age 42 years (range 17-60) diagnosed with hematological malignancies were conditioned with either cyclophosphamide and total body irradiation (n = 43) or busulphan and cyclophosphamide (n = 19). GVHD prophylaxis consisted of cyclosporin A (CsA) and prednisone (n = 48), CsA alone (n = 11), and CsA and methotrexate (n = 3). The median yield and purity of CD34+ cells after the procedure was 65% and 66% with Ceprate, and 48% and 86% with Isolex, respectively. The median number of CD34+ cells infused into the patients was 3.5 x 10(6)/kg (range 1-9.6). The median number of CD3+ cells administered was 0.4 x 10(6)/kg (range 0.01-2) using Ceprate and 0.14 x 10(6)/kg (range 0.03-2.5) using Isolex. Neutrophil recovery >500 and >1000/microl was achieved at a median of 13 days (range 8-22) and 14 days (range 9-31), respectively. Platelets recovered to >20,000 and >50,000/microl at a median of 13 days (range 0-128) and 18 days (range 0-180), respectively. The actuarial probability of acute GVHD II-IV was 10% (95% CI, 1-19%), and of extensive chronic GVHD 12% (95% CI, 11-13%).

High frequency of donor chimerism after allogeneic transplantation of CD34+-selected peripheral blood cells

Ex vivo T cell depletion of allogeneic grafts is associated with a high (up to 80%) rate of mixed chimerism (MC) posttransplantation. The number of transplanted progenitor cells is an important factor in achieving complete donor chimerism in the T cell depletion setting. Use of granulocyte colony-stimulating factor (G-CSF) peripheral blood allografts allows the administration of large numbers of CD34+ cells. We studied the chimeric status of 13 patients who received allogeneic CD34+-selected peripheral blood progenitor cell transplants (allo-PBPCTs/CD34+) from HLA-identical sibling donors. Patients were conditioned with cyclophosphamide (120 mg/kg) and total-body irradiation (13 Gy in four fractions). Apheresis products were T cell-depleted by the immunoadsorption avidin-biotin method. The median number of CD34+ and CD3+ cells infused was 2.8x10(6)/kg (range 1.9-8.6x10(6)/kg) and 0.4x10(6)/kg (range 0.3-1x10(6)/kg), respectively. Molecular analysis of the engraftment was performed using polymerase chain reaction (PCR) amplification of highly polymorphic short tandem repeat (PCR-STR) sequences in peripheral blood samples. MC was detected in two (15%) of 13 patients. These two patients relapsed at 8 and 10 months after transplant, respectively. The remaining 11 patients showed complete donor chimerism and were in clinical remission after a maximum follow-up period of 24 months (range 6-24 months). These results were compared with those obtained in 10 patients who were treated with T cell-depleted bone marrow transplantation by means of elutriation and who received the same conditioning treatment and similar amounts of CD3+ cells (median 0.45x10(6)/kg; not significant) but a lower number of CD34+ cells (median 0.8x10(6)/kg; p = 0.001). MC was documented in six of 10 patients (60%), which was significantly higher than in the allo-PBPCT/CD34+ group (p = 0.04). We conclude that a high frequency of complete donor chimerism is achieved in patients receiving allo-PBPCT/CD34+ and that this is most likely due to the high number of progenitor cells administered.

Hematopoietic stem cell transplantation in chronic lymphocytic leukemia: a report of 12 patients from a single institution

BACKGROUND

Stem-cell transplantation is a reasonable therapeutic approach for younger patients with high-risk CLL.

PATIENTS AND METHODS

Twelve patients (seven males; median age 47 years, range 29-51) with high-risk CLL underwent transplantation (allo, n = 7; auto, n = 5). The conditioning regimen consisted of cyclophosphamide and total body irradiation in 11 patients, and BEAC in the remaining one. Minimal residual disease (MRD) was assessed by cytofluorometry and PCR.

RESULTS

All 11 evaluable patients engrafted. Of the seven allografted patients, two died of treatment-related causes; three patients developed acute GVHD. No transplant-related mortality was observed in autografted patients. After transplantation, 10 of 11 patients evaluable for response achieved CR (91%; 95% CI 59%-100%) which was molecular in nine patients (82%; 95% CI 48%-98%). One patient in CR but MRD+ relapsed nine months after transplantation and died. Seven patients remain in molecular CR for a median of 16 months (range 1-58). Estimated actuarial survival and disease-free survival at two years is 81% (95% CI 43%-100%) and 71% (95% CI 43%-99%), respectively. Relapse risk at two years is 12.5% (95% CI 0%-35.5%).

CONCLUSIONS

Patients with high-risk CLL can achieve long-lasting molecular CR after SCT. The role of transplants in CLL management deserves investigation in controlled trials.

Demonstration of donor origin of CD34+ HLA-DR- bone marrow cells after allogeneic peripheral blood transplantation with a long follow-up

Peripheral blood progenitor cells (PBPC) are increasingly being used to perform allogeneic transplants (allo-PBPCT). An important issue regarding allo-PBPCT is the potential for long-term engraftment of human PBPC. A subset of bone marrow (BM) cells displaying the immunophenotype CD34+ HLA-DR- has functional properties associated with pluripotential stem cells. We studied the origin (donor vs recipient) of CD34+ HLA-DR- hematopoietic cells from patients having received allo-PBPCT and with a long follow-up (14+ to 21+ months). Chimeric status was determined after amplification by polymerase chain reaction (PCR) of short tandem repeat sequences (PCR-STR). Four patients (acute myeloid leukemia (n = 3), acute lymphoid leukemia (n = 1) were studied. CD34+ HLA-DR- cells from bone marrow aspirates were isolated by flow cytometry cell sorting. The mean percentage of CD34+ cells among the total nucleated BM cells from the four patients was 0.6+/-0.2% (mean +/- s.d.) (range, 0.31-1.27%). The CD34+ HLA-DR- cells accounted for 1.54+/-0.54 (range, 0.9-2.05%) of the CD34+ BM cells. The purity of the CD34+ HLA-DR- cells analyzed after sorting was higher than 94% in all sorted fractions. PCR-STR of these cells showed donor origin in all patients. The origin of CD34+ HLA-DR- bone marrow cells in patients treated with allo-PBPCT has not so far been analyzed. These results provide further evidence that G-CSF-mobilized PBPC contains cells which are capable of sustained long-term engraftment.

High incidence of chronic graft versus host disease after allogeneic peripheral blood progenitor cell transplantation. The Spanish Group of Allo-PBPCT

BACKGROUND AND OBJECTIVE

The incidence of acute GVHD (aGVHD) in allogeneic peripheral blood progenitor cell transplantation (allo-PBPCT) seems to be similar to that seen in allogeneic bone marrow transplantation (allo-BMT). In contrast, some preliminary results suggest that the incidence of chronic GVHD (cGVHD) might be higher. The aim of the present study was to analyze the actuarial probability of developing cGVHD in allo-PBPCT, its clinical manifestations and response to treatment.

METHODS

We have retrospectively analyzed clinical results from 21 allo-PBPCT recipients that had been transplanted at least 18 months before this study and that fulfilled the following criteria: HLA identical sibling donor, non T-cell depleted apheresis and more than 90 days of survival with sustained engraftment. The median follow-up was 12 months (range 4.5-22).

RESULTS

Twelve out of the 21 (57%) patients presented cGVHD, 1 limited and 11 extensive. The actuarial probability of cGVHD was 72.7% (95% CI, 49-96%). The median interval from transplant to onset was 180 days (range 95-270). Nine of the 12 cases (75%) presented combined skin and liver involvement. Of the other three, the liver was involved in one case; skin, mouth, and nail cGVHD was observed in another case; and skin and mouth involvement together with an obstructive pulmonary disease was observed in the remaining case. Under therapy, a complete resolution of cGVHD manifestations was achieved in five cases, and a partial improvement was attained in three other cases. In two responsive patients, cGVHD reappeared after stopping treatment. Four patients were refractory to the treatment.

INTERPRETATION AND CONCLUSIONS

It would appear from this retrospective and multicenter study that, after a median follow-up of 12 months, cGVHD after allo-PBPCT could be more frequent than after allo-BMT. A randomized trial with a large number of patients and a sufficient follow-up will be necessary to answer this question definitively.

[Second allogeneic progenitor cell transplantation for leukemia relapse: results in 10 patients]

BACKGROUND

Leukemia relapse is an important cause of treatment failure after allogeneic progenitor cells transplantation. A minority of patients achieve a long-term disease free survival with a second transplant, but the majority die of toxicity or relapse. We report our experience with second allogeneic transplant for leukemia relapse.

PATIENTS AND METHODS

Ten patients were treated with a second transplant. Their diagnosis were chronic myelogenous leukemia (n = 5) and acute leukemia (n = 5). The interval between transplants ranged from 4 to 59 months (median 26 months). Conditioning regimens were busulfan alone (n = 1), associated to cyclophosphamide (n = 6) or to cyclophosphamide plus etoposide (n = 3). Acute graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporin (CSA) (n = 4), CSA plus methotrexate (n = 4), CSA plus prednisolone (n = 1), or CSA, methotrexate plus partial T cell depletion (n = 1).

RESULTS

All patients engrafted after second transplant. Seven developed acute GVHD. Four out of the nine patients at risk (44%) developed chronic GVHD. Three had clinical criteria of hepatic veno-occlusive disease. Three patients died in complete remission due to treatment-related toxicity: pulmonary invasive aspergillosis during an acute GVHD, interstitial pneumonitis plus chronic GVHD, and, hepatic veno-occlusive disease, respectively. Two patients relapsed 4 and 5 months after second transplant. Five remained alive in complete remission after a median follow-up of 27 months. In all of them acute or chronic GVHD incidence and severity after second transplant was higher than after the first transplant. All surviving patients were transplanted more than 12 months after the first transplant.

CONCLUSIONS

A proportion of patients that relapse after an allogeneic progenitor cells transplant may benefit from second transplant; especially, young patients having a good performance status, and with a long interval between transplants.

Rapid engraftment without significant graft-versus-host disease after allogeneic transplantation of CD34+ selected cells from peripheral blood

We have prospectively evaluated the feasibility and results of the biotin-avidin immunoadsorption method (Ceprate SC system) for a phase I/II study of T-cell depletion of granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood progenitor cells (PBPC) for allogeneic transplantation. Twenty consecutive patients, median age, 40 years (21 to 54) and diagnoses of chronic myeloid leukemia in chronic phase (n = 5), acute myeloblastic leukemia (n = 7), acute lymphoblastic leukemia (n = 2), chronic myelomonocytic leukemia (n = 1), refractory anemia with excess of blasts in transformation (n = 3), histiocytosis X (n = 1), and chronic lymphocytic leukemia (n = 1), were conditioned with cyclophosphamide (120 mg/kg) and total body irradiation (13 Gy; 4 fractions). HLA identical sibling donors received G-CSF at 10 microg/kg/d subcutaneously (SC); on days 5 and 6 (19 cases) and days 5 to 8 (1 case) donors underwent 10 L leukapheresis. PBPC were purified by positive selection of CD34+ cells using immunoadsorption biotin-avidin method (Ceprate SC) and were infused in the patients as the sole source of progenitor cells. No growth factors were administered posttransplant. The median recovery of CD34+ cells after the procedure was of 65%. The median number of CD34+ cells infused in the patients was 2.9 (range, 1.5 to 8.6) x 10(6)/kg. The median number of CD3+ cells administered was 0.42 x 10(6)/kg (range, 0.1 to 2). All patients engrafted. Neutrophil counts >500 and >1,000/microL were achieved at a median of 14 days (range, 10 to 18) and 15 days (range, 11 to 27), respectively. Likewise, platelet counts >20,000 and >50,000/microL were observed at a median of 10 days (range, 6 to 23) and 17 days (range, 12 to 130), respectively. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine plus methylprednisolone. No patient developed either grade II to IV acute or extensive chronic GVHD. After a median follow-up of 7.5 months (range, 2 to 22) three patients have relapsed, and one of them is again in hematologic and cytogenetic remission after infusion of the donor lymphocytes. Two patients died in remission: one on day +109 of pulmonary aspergillosis and the other on day +251 of metastasic relapse of a previous breast cancer. Sixteen of the 20 patients are alive in remission after a median follow-up of 7.5 months (range, 2 to 22). In conclusion, despite the small number of patients and limited follow-up, it appears that this method allows a high CD34+ cell recovery from G-CSF mobilized PBPC and is associated with rapid engraftment without significant GVHD, and with low transplant related mortality.

[Hemopoietic progenitor cell transplantation: 20 years' experience at the Hematology School "Farreras-Valentí"/Clinical Hospital of Barcelona]

BACKGROUND

Hemopoietic progenitor cell transplantation (HPCT) is acquiring an increasing role in the therapy for a variety of disorders. In this study, main characteristics and results of HPCT along 20 years are analyzed from the experience of Postgraduate School of Hematology "Farreras-Valentí" at the Hospital Clínic in Barcelona.

PATIENTS AND METHODS

Six-hundred ninety-five patients transplanted between June 1976 and January 1996 were analyzed. Median age (range) were 33 (4-63) years. The following aspects were considered: donor type, source or progenitor cells, type of disease and disease-stage at transplantation, transplant related mortality and survival.

RESULTS

A total of 714 HPCT were performed (448 allogeneic, 13 isogeneic, 253 autogeneic). Allogeneic HPCT were from an HLA-identical sibling in 408 cases, from other familial donors in 10, and from non-familial donors in 30. Most HPCT from non-familial donors (93%) were performed during the last five years of the study (1991-1995). The source of hemopoietic progenitor cells was bone marrow in 625 instances (88%), peripheral blood in 88 (12%), and fetal liver in one. During more than 15 years, the only source of progenitors was the bone marrow; in contrast, in the last 3 years (1993-1995) transplants using peripheral blood were predominant. Main indications for HPCT were the following: acute leukemias (n = 387) (54%), chronic leukemias (n = 134) (19%), severe aplastic anemia (n = 58) (8%), lymphomas (n = 80) (11%), multiple myeloma (n = 39) (5%) and myelodysplastic syndromes (n = 14) (2%). In patients with hematological malignancies (n = 656), HPCT was performed in first complete remission or in first chronic phase in 321 instances (49%), in subsequent remissions in 144 (22%), and in more advanced stages in the remaining 191 (29%). In the more recent years, a progressive decrease in the number of HPCT for acute leukemia or aplastic anemia was observed, contrasting with an increase in transplants for lymphoma, multiple myeloma and myelodysplastic syndromes. Of note, a significant decrease in transplant related mortality was evident along the years, both after autogeneic HPCT (21% during 1985-1992 and 6% thereafter) (p = 0.001) and after allogeneic transplantation (54%, 44%, and 20% during the periods 1976-1984, 1985-1992 and 1993-1995, respectively) (p = 0.004). The fact translated into an increase in the actuarial probability of survival after allogeneic HPCT (25%, 33% and 58% in the three mentioned periods, respectively) (p = 0.0003), and after autogeneic HPCT (33% in the interim 1985-1992, and 55% in the period 1993-1995) (p = 0.001).

CONCLUSIONS

During the last 20 years, HPCT has significantly evolved in aspects such as type of donor, source of progenitor cells and indications. Remarkably, a progressive decrease in transplant related mortality has been observed translating into a improvement in survival after the procedure.

Successful autografting in chronic myelogenous leukaemia using Philadelphia negative blood progenitor cells mobilized with rHuG-CSF alone in a patient responding to alpha-interferon

Several non-randomized studies suggest a possible survival advantage for chronic myelogenous leukaemia (CML) patients treated with an autologous stem-cell transplantation. Due to the possible contribution of residual leukaemic cells present in the inoculum in post-transplant relapse, several methods are being evaluated to eliminate neoplastic cells or to select 'normal' (Ph1 negative) progenitor cells for autografting. Recently, several studies have shown that Ph1 negative blood progenitor cells can be mobilized by rHuG-CSF alone in patients who have a cytogenetic response to alpha-interferon (IFN). We describe the first case, as far as we are aware, of a CML patient responding to IFN autografted by using blood progenitor cells collected by rHuG-CSF alone.

Allogeneic peripheral blood progenitor cell transplantation: analysis of short-term engraftment and acute GVHD incidence in 33 cases. allo-PBPCT Spanish Group

The results of 33 allogeneic peripheral blood progenitor cells transplants (allo-PBPCT) in adult patients with hematologic malignancies were analyzed in a retrospective and multicenter study. In 21 of 33 cases (63%) the disease was refractory or in advanced stage and eight of the 33 cases (24%) were second transplants after relapse. Donors were treated with a median of 10 (4-16) micrograms/kg/day of rhG-CSF subcutaneously for 5-7 days. Three required a central venous line for harvesting. Peripheral blood leukapheresis product contained a median of 5.9 (1.8-13) 10(6)/kg CD34+ cells and a median of 309.5 (153-690) 10(6)/kg CD3+ cells. After a myeloablative regimen, all patients received PBPC from HLA-identical donors as the sole source of progenitor cells. Cyclosporin A (CsA) alone (n = 2), CsA and steroids (n = 9), and CsA and methotrexate (MTX) (n = 22) were used for GVHD prophylaxis. Growth factors post-transplant were given to 11 patients (33%). The median follow-up of the patients was 3 months. Actuarial median day for hemopoietic recovery was: neutrophils to >0.5 (>1) x 10(9)/l, day 14 (15); platelets to >20 (>50) x 10(9)/l, day 14 (21). The quantity of CD34+ cells infused did not significantly affect the engraftment kinetics, from a starting cutoff of 2.5 x 10(6)/kg. The speed of neutrophil recovery seemed to be influenced strongly by using rhG-CSF post-transplant and marginally by the type of GVHD prophylaxis. Actuarial probability for grade II-IV acute GVHD of the whole group was 37% (95% Cl, 20-54%).

[Treatment with fludarabine of lymphoid neoplasms with low grade malignity resistant to treatment or in relapse]

BACKGROUND

In the last years the treatment of patients with chronic lymphocytic leukemia (CLL) and low-grade lymphomas (NHL) has changed because of the introduction of new agents, mainly the purine analogs. We report our experience with fludarabine in patients with indolent lymphoid malignancies that were previously treated with conventional agents.

PATIENTS AND METHODS

Twenty patients were studied. Eleven had CLL and nine NHL. Among the patients with CLL and NHL, 72 and 100%, respectively, had advanced disease. All patients had previously been treated. Fludarabine was administered by intravenous infusion at a dose of 25 mg/m2, for 5 days every 4 weeks until a maximum of 6 cycles.

RESULTS

Neither complete response (CR) nor partial response (PR) was recorded in patients with CLL; 4 (36%) achieved clinical improvement. Among the 9 patients with NHL, 3 (33%) had a CR and one a PR; two of the 3 patients with CR also achieved a molecular remission. In 3 patients with CLL their disease progressed from stage II to IV. Three patients (one with CLL and two with NHL) developed high-grade lymphoma during or immediately after the treatment with fludarabine. The major toxicities were infections: 3 patients had lobar pneumonia and one an interstitial pneumonia without microbiological identification.

CONCLUSIONS

Fludarabine is an active agent in patients with low-grade lymphoid malignancies refractory to the treatment or in relapse. The possibility of obtaining molecular remissions makes this agent specially interesting in those therapies including hemopoietic progenitors transplantation as intensification treatment.

Study of hematopoietic chimerism following allogeneic peripheral blood stem cell transplantation using PCR amplification of short tandem repeats

Allogeneic peripheral blood progenitor cell transplantation (PBPCT) is increasingly being used to treat hematologic malignancies. However, the capacity of PBPC to maintain long-term hematopoiesis remains controversial. To add further information to this issue we studied the chimeric status in 12 patients receiving G-CSF-mobilized PBPC from HLA-identical sibling donors. All patients were conditioned with cyclophosphamide and total body irradiation. In six cases the apheresis product was partially T-cell depleted by counterflow centrifugation (n = 2) or the immunoadsorption biotin-avidin method (n = 4). The follow-up was longer than 6 months in five patients, with a maximum of 420 days. Molecular analysis of the engraftment was done using PCR amplification of short tandem repeats. Apparent complete donor chimerism was detected in all patients between 28 and 420 days after engraftment. This study indicates that full short-term engraftment is achieved in patients receiving allogeneic G-CSF-mobilized PBPC from healthy donors and suggests that this might also be true for long-term engraftment.

Effects of G-CSF administration and peripheral blood progenitor cell collection in 20 healthy donors

The effects of both daily G-CSF administration and subsequent peripheral blood progenitor cell collection (PBPCC) by apheresis on 20 healthy adult donors were studied. All received daily G-CSF (filgrastim) 10 micrograms/kg for 5-7 days by subcutaneous injection. G-CSF administration was well tolerated, except for moderate bone pain and headache. Peak values of CD34+ cells were observed on days 5 (n = 12) or 6 (n = 8). In all donors a significant increase in CD3+, CD4+, CD8+, CD19+, and NK cells was observed on day 5 in relation to the baseline values. CD4/CD8 lymphocyte ratio was unmodified by G-CSF. None of the donors required a central venous line for PBPCC. Immediately after PBPCC, a platelet count below 100 x 10(9)/1 was observed in nine of 18 cases, although in all donors platelet counts were over 100 x 10(9)/1 7 days later. A lymphocytopenia on day 7 following PBPCC was observed, although there was a tendency to achieve baseline values 30-90 days after the procedure. Mean numbers ( +/- SD) of collected cells x 10(6)/kg after a median of two (1-4) apheresis sessions and a median of 20 1 (10-40) processed were: CD34+ 5.5 ( +/- 2.3), CD3+ 326 ( +/- 105), CD4+ 207 ( +/- 64), CD8+ 164 ( +/- 60), CD19+ 88 ( +/- 32), and NK cells 32 ( +/- 14). We conclude that G-CSF administration to healthy donors is a well-tolerated procedure which is associated with (a) obtaining a high number of hematopoietic progenitor cells, and (b) a significant increase in T, B, and NK cells in donors' blood. In addition, PBPCC by apheresis results in a moderate, rapidly reversible, and clinically irrelevant thrombocytopenia and a moderate lymphocytopenia, which tends to resolve within 3 months following the procedure.

Allogenic transplants with peripheral blood progenitor cells: a report of six cases

Six patients with high-risk leukaemia received a myeloablative regimen followed by allogeneic peripheral blood progenitor cells transplantation (PBPCT) from an HLA-identical sibling donor. Donors received 10-12 mu g/kg/day of G-CSF subcutaneously for 5 days. G-CSF was well tolerated except for moderate bone pain. Peripheral blood leukapheresis product contained 1-4 times more CD34+ cells and approximately a log more of T lymphocytes than marrow grafts from normal donors. In the two first cases the leukapheresis product was partially depleted of T-lymphocytes using counterflow centrifugation. No growth-factors were administered post-transplant. GVHD prophylaxis consisted of cyclosporin A (CyA) in one case, and CyA and methotrexate in five cases. All patients engrafted with a neutrophil count reaching more than 0.5 x 10(9)/L by day 12 to 21 post-transplant and a platelet count above 20 x 10(9)/L by day 6 to 41 post-transplant. Acute GVHD was clinical grade 0 (n = 2), I (n = 1), II (n = I), grade III (n = I) and grade IV (n = 1). One case presents an extensive chronic cutaneous GVHD and is currently being treated with methylprednisolone. In conclusion, allogeneic transplants using PBPC can be performed safely. This may result in a rapid neutrophil and platelet engraftment, without an apparent increased risk of GVHD.

[Allogeneic transplant of peripheral blood hematopoietic progenitors. Preliminary experience]

Myeloablative treatment followed by allogeneic transplantation of peripheral blood hemopoietic progenitors (alloPBT) was administered to five leukemia patients with a high risk of relapse. The donors subcutaneously received 10 micrograms/kg/day of G-CSF for five days. The tolerance to this medication was good with only complaints of moderate bone pain. Two of the peripheral blood donors had previously been bone marrow donors and both expressed their preference for the new method. The product of peripheral blood leukapheresis contained from one to four-fold more hemopoietic progenitors and approximately ten-fold more T-lymphocytes than the bone marrow received from normal donors. Prophylaxis of the graft versus host disease (GVHD) consisted of cyclosporine A (CsA) in one case and CsA and methotrexate (MTX) in four cases. The bone marrow implantation was verified with a neutrophil count of up to more than 0.5 x 10(9)/l between days 12 to 21 after transplant and a platelet count higher than 20 x 10(9)/l from days 11 to 41 after transplant. Acute GVHD was clinical grade O (two cases), II (one case) and grade III (two cases). In conclusion, alloPBT may be more safely and comfortably performed to the donor. This method may provide rapid recovery of neutrophils and platelets in patients without an apparent increase in the risk of developing graft versus host disease.

Adult T-Cell Leukaemia-Lymphoma Relapsing as Hodgkin Disease Nodular Sclerosis Subtype

Adult T-cell leukaemia-lymphoma (ATLL) is a distinct disease aetiologically associated with HTLV-I. Hypercalcaemia, organomegaly and a pleomorphic blood picture characterized by the presence of convoluted CD4+CD25+ lymphocytes are the main disease features. We report a patient with a well documented ATLL who relapsed after a long-lasting remission induced by deoxycoformycin treatment. At relapse, the blood picture was consistent with ATLL whereas the histological and immunophenotypical features of the lymph node were indistinguishable from those seen in Hodgkin disease (HD) nodular sclerosis subtype. The monoclonal integration of HTLV-I proviral DNA in the lymph node was demonstrated by Southern blot. The unusual evolution of this case emphasizes the difficulties of differential diagnosis between HD and ATLL with atypical histology and adds new support to the concept of a possible viral participation in a subset of HD cases.

Leukemia after true histiocytic lymphoma: another type of acute monocytic leukemia with histiocytic differentiation (AML-M5c)?

The case of a 44-year-old man diagnosed of a true histiocytic lymphoma who, after autologous bone marrow transplantation, developed leukemia with histiocytic cells is reported. Morphologic, cytochemical, immunophenotypic and genotypic characteristics of malignant cells are described, and the literature about this and related entities is reviewed. In addition, comparison with a recent report of malignant histiocytosis with leukemic involvement is established and its inclusion in the recently proposed subtype of monocytic leukemia with histiocytic differentiation (M5c), suggested.