Development of adaptive immune effector therapies in solid tumors

State-of-the-art treatment strategies have drastically ameliorated the outcome of patients affected by cancer. However, resistant and recurrent solid tumors are generally nonresponsive to conventional therapies. A central factor in the sequence of events that lead to cancer is an alteration in antitumor immune surveillance, which results in failure to recognize and eliminate the transformed tumor cell. A greater understanding of the dysregulation and evasion of the immune system in the evolution and progression of cancer provides the basis for improved therapies. Targeted strategies, such as T-cell therapy, not only generally spare normal tissues, but also use alternative antineoplastic mechanisms that synergize with other therapeutics. Despite encouraging success in hematologic malignancies, adaptive cellular therapies for solid tumors face unique challenges because of the immunosuppressive tumor microenvironment, and the hurdle of T-cell trafficking within scarcely accessible tumor sites. This review provides a brief overview of current cellular therapeutic strategies for solid tumors, research carried out to increase efficacy and safety, and results from ongoing clinical trials.

Extracellular NK histones promote immune cell anti-tumor activity by inducing cell clusters through binding to CD138 receptor

Background

Natural killer (NK) cells are important anti-tumor cells of our innate immune system. Their anti-cancer activity is mediated through interaction of a wide array of activating and inhibitory receptors with their ligands on tumor cells. After activation, NK cells also secrete a variety of pro-inflammatory molecules that contribute to the final immune response by modulating other innate and adaptive immune cells. In this regard, external proteins from NK cell secretome and the mechanisms by which they mediate these responses are poorly defined.

Methods

TRANS-stable-isotope labeling of amino acids in cell culture (TRANS-SILAC) combined with proteomic was undertaken to identify early materials transferred between cord blood-derived NK cells (CB-NK) and multiple myeloma (MM) cells. Further in vitro and in vivo studies with knock-down of histones and CD138, overexpression of histones and addition of exogenous histones were undertaken to confirm TRANS-SILAC results and to determine functional roles of this material transferred.

Results

We describe a novel mechanism by which histones are actively released by NK cells early after contact with MM cells. We show that extracellular histones bind to the heparan sulfate proteoglycan CD138 on the surface of MM cells to promote the creation of immune-tumor cell clusters bringing immune and MM cells into close proximity, and thus facilitating not only NK but also T lymphocyte anti-MM activity.

Conclusion

This study demonstrates a novel immunoregulatory role of NK cells against MM cells mediated by histones, and an additional role of NK cells modulating T lymphocytes activity that will open up new avenues to design future immunotherapy clinical strategies.

Changing prognosis in paroxysmal nocturnal haemoglobinuria disease subcategories: an analysis of the International PNH Registry

BACKGROUND

Paroxysmal nocturnal haemoglobinuria (PNH) is a rare disease. Although much progress has been made in the understanding of the pathophysiology of the disease, far less is known with respect to the clinical outcomes of patients with PNH. Few retrospective studies provide survival estimates, and even fewer have explored the clinical heterogeneity of the disease. Haemolytic and aplastic anaemia (AA) forms of the disease have been recognised as main disease categories, with the haemolytic form being associated with the worst prognosis by the largest studied cohort some years ago.

AIMS

To describe mortality and causes of death in PNH overall and by PNH classification and to evaluate risk factors associated with mortality.

METHODS

We analysed data of 2356 patients enrolled in the International PNH Registry with multivariate analyses, using time-dependent covariates. Patients were classified into haemolytic, AA/PNH syndrome or intermediate PNH.

RESULTS

Overall, 122 (5.2%) patients died after enrolment, the incidence according to subcategories being 5.1, 11.7, 2.0 and 4.8% for patients with haemolytic PNH, AA-PNH, intermediate and insufficient data respectively. Older age and decreased performance status also affected survival in multivariate analysis. Improved outcome of patients with haemolytic PNH suggests that eculizumab treatment in PNH may be associated with improved survival.

CONCLUSION

A detailed analysis of clinical presentations and causes of death in patients with PNH, overall and by disease subcategories, provide evidence that in the current era, patients with haemolytic PNH are no longer those who harbour the worst prognosis. This finding differs sharply from what has been previously reported.

GvHD after umbilical cord blood transplantation for acute leukemia: an analysis of risk factors and effect on outcomes

Using the Center for International Blood and Marrow Transplant Research (CIBMTR) registry, we analyzed 1,404 UCBT patients [single (< 18 years) = 810, double (≥ 18 years) = 594] with acute leukemia to define the incidence of acute and chronic graft-vs.-host disease (GVHD), analyze clinical risk factors and investigate outcomes. After single UCBT, 100-day incidence of grades II–IV aGVHD was 39% (95% CI, 36–43%), grades III–IV aGVHD was 18% (95% CI, 15–20%), and 1-year cGVHD was 27% (95% CI, 24–30%). After double UCBT, 100-day incidence of grades II–IV aGVHD was 45% (95% CI, 41%–49%), grades III–IV aGVHD was 22% (95% CI, 19–26%), and 1-year cGVHD was 26% (95% CI, 22–29%). For single UCBT, multivariate analysis showed that absence of anti-thymocyte globulin (ATG) was associated with aGVHD, whereas prior aGVHD was associated with cGVHD. For double UCBT, absence of ATG and myeloablative conditioning were associated with aGVHD, while prior aGVHD predicted for cGVHD. Grades III–IV aGVHD led to worse survival whereas cGVHD had no significant effect on disease-free or overall survival. GVHD is prevalent after UCBT with severe aGVHD leading to higher mortality. Future research in UCBT should prioritize prevention of GVHD.

Allogeneic hematopoietic SCT in multiple myeloma: long-term results from a single institution

The role of allogeneic hematopoietic SCT (allo-HCT) in multiple myeloma (MM) remains controversial. A total of 58 patients received an allo-HCT (25 of them with myeloablative conditioning-allo-MAC-and 33 with reduced-intensity conditioning-allo-RIC) at our institution over a 28-year period. The CR rate for allo-MAC was 36%. The incidence of grade III-IV acute GVHD (aGVHD) and chronic GVHD (cGVHD) was 28% and 39%, respectively The TRM at any time was 60% and the main causes of death were aGVHD or infectious complications not directly related to GVHD. The estimated PFS and OS at 15 years were 8% and 15%, respectively. The CR rate with allo-RIC was 45%. The incidence of grade III-IV aGVHD and cGVHD were 24% and 41%, respectively. The TRM at any time was 33% and was mainly related to aGVHD. The estimated PFS and OS at 5 years were 22% and 38%, respectively. Despite its high TRM, a proportion of patients with high-risk myeloma (early relapse and newly diagnosed ultrahigh risk) may obtain long-term disease control with allo-HCT. New approaches aimed at decreasing the incidence of aGVHD, and consequently to decrease the TRM, are needed.

Transmissible cytotoxicity of multiple myeloma cells by cord blood-derived NK cells is mediated by vesicle trafficking

Natural killer cells (NK) are important effectors of anti-tumor immunity, activated either by the downregulation of HLA-I molecules on tumor cells and/or the interaction of NK-activating receptors with ligands that are overexpressed on target cells upon tumor transformation (including NKG2D and NKP30). NK kill target cells by the vesicular delivery of cytolytic molecules such as Granzyme-B and Granulysin activating different cell death pathways, which can be Caspase-3 dependent or Caspase-3 independent. Multiple myeloma (MM) remains an incurable neoplastic plasma-cell disorder. However, we previously reported the encouraging observation that cord blood-derived NK (CB-NK), a new source of NK, showed anti-tumor activity in an in vivo murine model of MM and confirmed a correlation between high levels of NKG2D expression by MM cells and increased efficacy of CB-NK in reducing tumor burden. We aimed to characterize the mechanism of CB-NK-mediated cytotoxicity against MM cells. We show a Caspase-3- and Granzyme-B-independent cell death, and we reveal a mechanism of transmissible cell death between cells, which involves lipid-protein vesicle transfer from CB-NK to MM cells. These vesicles are secondarily transferred from recipient MM cells to neighboring MM cells amplifying the initial CB-NK cytotoxicity achieved. This indirect cytotoxicity involves the transfer of NKG2D and NKP30 and leads to lysosomal cell death and decreased levels of reactive oxygen species in MM cells. These findings suggest a novel and unique mechanism of CB-NK cytotoxicity against MM cells and highlight the importance of lipids and lipid transfer in this process. Further, these data provide a rationale for the development of CB-NK-based cellular therapies in the treatment of MM.

Differences in cytomegalovirus replication quantified using quantitative polymerase chain reaction and antigenemia after allogeneic stem cell transplantation

Fifty percent of allogeneic stem cell recipients develop cytomegalovirus (CMV) infection in the first 100 days posttransplantation. Various methods have been used to determine CMV infections, including antigenemia assay and real-time polymerase chain reaction (RT-PCR). Although antigenemia assay has been used more frequently, this technique is less sensitive than RT-PCR. In contrast, RT-PCR has a low positive predictive value for CMV end-organ disease. Cytomegalovirus infections were analyzed in 41 peripheral blood samples from allogeneic stem cell recipients using both antigenemia assay and RT-PCR; results were discordant in 36.6% of patients. Although the antigenemia assay detected CMV replication in 29.2% of cases, RT-PCR was positive in 65.8%. In 83.3% of patients, results detected using the antigenemia assay were delayed by a median (range) of 5 (2-20) weeks compared with positive RT-PCR results. Within the first 100 days posttransplantation, higher levels of viral replication measured using RT-PCR were observed in patients with vs without antigenemia. In addition, in patients with antigenemia, viral load was significantly higher before day 100 than after (P=.01 and P=.008, respectively) compared with those without antigenemia.

Clinical utility of real-time polymerase chain reaction to quantify cytomegalovirus replication in allogeneic stem cell transplant recipients with different prevention strategies

Cytomegalovirus (CMV) end-organ disease is a serious, frequent complication after allogenic stem cell transplantation (Allo-SCT). There are two prevention strategies: universal prophylaxis and preemptive therapy. Preemptive therapy is administered based on the results of sensitive techniques that detect the viral infection. We analyzed 41 peripheral blood Allo-SCT recipients: 34 received prophylaxis and seven preemptive treatment. Viral infections determined using real-time polymerase chain reaction (RT-PCR) assays occurred at an overall incidence of 65.8%. The viral loads quantified by RT-PCR were compared among the prophylaxis versus the preemptive group. Overall, the median viral load was significantly higher in the preemptive compared with the prophylaxis group (P=.002). Furthermore, within the first 100 days posttransplantation, viral load values were higher among patients undergoing preemptive therapy (P=.009).

Results of the EBMT activity survey 2005 on haematopoietic stem cell transplantation: focus on increasing use of unrelated donors

This EBMT activity report documents the haematopoietic stem cell transplantation (HSCT) activity in Europe in 2005. It provides numbers of HSCT by indication, donor type and stem cell source, lists the new practice of planned double transplants with allogeneic after autologous HSCT and concentrates on the increasing role of unrelated transplants over the last years. In 2005, there were 24,168 first HSCT, 8890 allogeneic (37%), 15,278 autologous (63%) and 3773 additional re- or multiple transplants reported from 597 centres in 43 participating countries. Main indications were leukaemias (7404 (31%; 82% allogeneic)); lymphomas (13,825 (57%; 89% autologous)); solid tumours (1655 (7%; 92% autologous)) and non-malignant disorders (1131 (5%; 93% allogeneic)). A total of 671 planned allogeneic after autologous HSCT were reported; the majority for myeloma (52%), lymphoma (28%) and acute myeloid leukaemia (11%). Compared to 2004, there was a 20% increase in allogeneic HSCT; numbers of autologous HSCT remained constant. The most noticeable increase was in unrelated HSCT, which comprise 41% of all allogeneic HSCT. Unrelated HSCT were preferentially performed for leukaemias and in countries with high income according to World Bank criteria. These data illustrate the current experience in Europe and form the basis for patient counselling and decisions making at health care institutions.

EBMT activity survey 2004 and changes in disease indication over the past 15 years

This fifteenth annual European Group for Blood and Marrow Transplantation activity report lists the transplant activity in Europe in 2004 and documents the changes in indication over the past 15 years. In 2004, there were 22 216 first hematopoetic stem cells (HSCT), 7407 allogeneic (33%), 14 809 autologous (67%) and 4378 additional re- or multiple transplants reported from 592 centres in 38 European and five affiliated countries. Main indications were leukemias (7045 (32%; 78% allogeneic)); lymphomas (12 310 (55%; 94% autologous)); solid tumors (1759 (8%; 93% autologous)) and nonmalignant disorders (1015 (5%; 92% allogeneic)). In comparison, 145 teams from 20 countries performed 4234 HSCT (2137 allogeneic, 50%; 2097 autologous, 50%) in 1990. The overall increase was accompanied by major changes. Stem cell source changed from bone marrow to peripheral blood. More than one-third of allogeneic HSCT are now from unrelated donors. Reduced intensity conditioning is employed for one-third of allogeneic HSCT. Leukemias for allogeneic and lymphoproliferative disorders for autologous HSCT continue to increase. The decline in HSCT for chronic myeloid leukemia appears to level off for the first time since 1999. These data are informative for patient counselling and decision making for health care professionals.

G-CSF increases the number of peripheral blood dendritic cells CD16+ and modifies the expression of the costimulatory molecule CD86+

Dendritic cells (DC) play a key role in initiating immune reactions after allogeneic stem cell transplantation. The two main peripheral blood DC populations are myeloid (DC1) and lymphoplasmacytoid (DC2). A new subset of myeloid DC, expressing CD16, has been identified. We analyzed the number and CD86 expression of DC subsets in peripheral blood of 18 healthy donors, before and after granulocyte colony-stimulating factor (G-CSF) and in the inoculum of allogeneic peripheral blood transplants (allo-PBT; n=100) and allogeneic bone marrow transplants (allo-BMT; n=22). Granulocyte colony-stimulating factor administration increased the median number of DC1 (P=0.0007), of DC2 (P<0.0001) and of DC CD16+ (P=0.0001). Granulocyte colony-stimulating factor administration was also associated with a significant decrease of CD86 expression on DC1 (P=0.0003) and with a trend for an increase on DC CD16+ (P=0.07). Recipients of allo-PBT received similar quantities of DC1 and higher doses of DC2 and DC CD16+ than recipients of allo-BMT (P=0.5; P=0.0001; P<0.0001, respectively). Granulocyte colony-stimulating factor modifies the number of DC in peripheral blood and the expression of the costimulatory molecule CD86. This resulted in a different composition of DC2 and especially of DC CD16+ in the harvests, which might explain some of the differences observed in allogeneic reactions after allo-PBT with respect to allo-BMT.

Allogeneic and autologous transplantation for haematological diseases, solid tumours and immune disorders: definitions and current practice in Europe

The Accreditation Subcommittee of the EBMT regularly publishes special reports on current practice of haemopoietic stem cell transplantation for haematological diseases, solid tumours and immune disorders in Europe. Major changes have occurred since the first report was published in 1996. Haemopoietic stem cell transplantation today includes grafting with allogeneic and autologous stem cells derived from bone marrow, peripheral blood and cord blood. With reduced intensity conditioning regimens in allogeneic transplantation, the age limit has increased, permitting the inclusion of older patients. New indications have emerged such as autoimmune disorders and AL amyloidosis for autologous, and solid tumours for allogeneic transplants. The introduction of alternative therapies has challenged well-established indications such as imatinib for chronic myeloid leukaemia. An updated report with revised tables and operating definitions is presented here.

Change in stem cell source for hematopoietic stem cell transplantation (HSCT) in Europe: a report of the EBMT activity survey 2003

This EBMT activity survey presents the status of hematopoietic stem cell transplantation (HSCT) in Europe 2003 and focuses on changes in stem cell source over the last decade. There were 21 028 first HSCT, 7091 allogeneic (34%), 13 937 autologous (66%) and 4179 additional re- or multiple transplants reported from 597 centers in 42 European countries in the year 2003. Main indications were leukemias (6613 (31%; 78% allogeneic)); lymphomas (11 571 (55%; 93% autologous)); solid tumors (1792 (9%; 92% autologous)) and nonmalignant disorders (898 (5%; 93% allogeneic)). In 1991, the vast majority of autologous and all allogeneic HSCT were still bone marrow (BM) transplants. Stem cell source changed rapidly to peripheral blood (PB) for autologous HSCT between 1992 and 1996. In 2003, 97% of autologous HSCT were PB derived. The change to PB for allogeneic HSCT followed 3 years later and occurred at a lower rate. In 2003, 65% of all allogeneic HSCT were PB derived. The change in stem cell source was not homogeneous. It was associated with donor type, main diagnosis, disease stage and it differed between European countries. In 2003, bone marrow remains a significant source of stem cells in some European countries for autologous HSCT and for nonmalignant disorders in allogeneic HSCT.

Transmission of donor illness by stem cell transplantation: should screening be different in older donors?

With increasing donor age, the potential of transmitting diseases from donor to recipient reaches new dimensions. Potentially transmittable diseases from donors include infections, congenital disorders, and acquired illnesses like autoimmune diseases or malignancies of hematological or nonhematological origin. While established nonmalignant or malignant diseases might be easy to discover, early-stage hematological diseases like CML, light-chain multiple myelomas, aleukemic leukemias, occult myelodysplastic syndromes and other malignant and nonmalignant diseases might not be detectable by routine screening but only by invasive, new and/or expensive diagnostic tests. In the following article, we propose recommendations for donor work-up, taking into consideration the age of the donors. In contrast to blood transfusions, stem cells from donors with abnormal findings might still be acceptable for HCT, when no other options are available and life expectancy is limited. This issue is discussed in detail in relation to the available donor and stem cell source. Finally, the recommendations presented here aim at harmonized worldwide work-up for donors to insure high standard quality.

Haematopoietic stem cell transplantation (HSCT) in Europe 2002. Changes in indication and impact of team density. A report of the EBMT activity survey

This 2002 European Group for Blood and Marrow Transplantation (EBMT) activity survey concentrates on current status, increase and decrease in haematopoietic stem cell transplantation (HSCT) activity in Europe and investigates the association of transplant rates with team density. In 2002, there were 20 207 HSCT, 6915 allogeneic (34%), 13 292 autologous (66%) and 3947 additional re- or multiple transplants collected from 586 centres in 39 European countries. Main indications were leukaemias (6523 (32%; 76% allogeneic)); lymphomas (10 760 (53%; 92% autologous)); solid tumours (1913 (9%; 92% autologous)) and nonmalignant disorders (874 (4%; 92% allogeneic)). Compared to 2001, there were increases (>10%) for AML, ALL 1st CR, CML not 1st cP, MDS, SAA and CLL in allogeneic HSCT and for MDS, Ewing's sarcoma, soft-tissue sarcoma and ovarian cancer in autologous HSCT. Decreases (>10%) were observed in autologous HSCT for acute leukaemias beyond 1st CR, CML cP, glioma, breast cancer and lung cancer. Correlation of transplant rates (number of transplants per 10 million inhabitants) with team density (number of transplant teams per 10 million inhabitants) suggests different diffusion patterns for autologous compared to allogeneic HSCT. These data describe current practice for blood and marrow transplantation in Europe and give some hints about mechanisms involved in HSCT rates.

Elderly age and prior autologous transplantation have a deleterious effect on survival following allogeneic peripheral blood stem cell transplantation with reduced-intensity conditioning: results from the Spanish multicenter prospective trial

Over a 3-year period, 145 patients ineligible for myeloablative conditioning underwent reduced-intensity conditioning (RIC) hematopoietic stem cell transplantation (SCT) from an HLA-identical sibling in a prospective study. The median age was 54 years, 88 patients were male and 61 patients were beyond the early-intermediate phase of their disease. The 100-day probability of developing grade II-IV acute graft-versus-host disease (GVHD) was 34%, and the 1-year probability of developing chronic extensive GVHD was 41%. The 1-year probabilities of transplant-related mortality (TRM), overall (OS) and progression-free survival were 20, 60 and 52%, respectively. Multivariate analyses found a better OS in: (i) patients <60 years; and (ii) recipients of a first SCT; and a higher TRM in: (i) age >60 years, (ii) recipients of a prior autologous SCT, and (iii) an ECOG performance status >1. The 1-year TRM in patients with 0 or 1 and >2 of the above-mentioned adverse prognostic factors were 17 vs 53%, respectively (P<0.001). In summary, our study shows that elderly patients have a higher TRM following an RIC protocol. However, age by itself should not preclude these RIC transplants, since TRM appears to be unacceptably high only in the presence of additional adverse factors.

Hematopoetic stem cell transplantation for solid tumors in Europe

BACKGROUND

Hematopoetic stem cell transplants (HSCT) are discussed as treatment options for patients with solid tumors. Transplant numbers have changed substantially over the last decade, few controlled studies are available and different opinions prevail. Objective information on current practice is needed.

PATIENTS AND METHODS

Data from 27 902 HSCT for solid tumors (2% allogeneic, 98% autologous), collected by the European Group for Blood and Marrow Transplantation (EBMT) activity survey from 1991 to 2002 were used to assess trends, transplant rates and coefficient of variation of transplant rates in Europe.

RESULTS

Transplant numbers increased from 536 in 1991 to 4154 in 1997 and decreased to 1913 in 2002. Indications were neuroblastoma (2504 HSCT; 9%), glioma (662 HSCT; 2%), soft tissue sarcoma (1253 HSCT; 4%), germ cell cancer (3291 HSCT; 12%), breast cancer (13 524 HSCT; 48%), Ewing's sarcoma (1896 HSCT; 7%), lung cancer (387 HSCT; 1%), ovarian cancer (845 HSCT; 3%) and other solid tumors (3540 HSCT; 14%). Allogeneic cells were used in <20 cases up to 1997; since then allogeneic HSCT increased to 159 in 2002, mainly for renal cell carcinoma. Low coefficients of variation in transplant rates (<60%) are observed for Ewing's sarcoma (<56.5%), suggesting consensus for this indication.

CONCLUSIONS

These data give an overview on current practice of HSCT for solid tumors in Europe. They provide objective information for health-care providers and patient counselling.

High-dose therapy/autologous stem cell transplantation in patients with chemosensitive multiple myeloma: predictors of complete remission

High-dose therapy (HDT) followed by autologous stem cell support is widely used as intensification treatment in patients with multiple myeloma (MM) responsive to the initial chemotherapy. However, there is growing evidence that only the subset of patients who achieve complete remission (CR) actually benefit from this approach. The aim of this study was to identify pretransplant predictors of CR in responding myeloma patients intensified with HDT. A total of 59 patients with chemosensitive disease received myeloablative therapy. The intensification regimen consisted of MEL-200 (23), MEL-140/TBI 12 Gy (21) or busulfan-based regimens (15). Serum and urine negative immunofixation were required for CR. After HDT, the CR rate increased from 8 to 37%. For the overall series, the median event-free survival (EFS) and overall survival (OS) from the initiation of therapy were 41 and 68 months, respectively. Patients who achieved CR had an EFS (median 47 vs 36 months; P=0.023) as well as an OS (median not reached vs 60 months; P=0.006) significantly longer than those attaining a lower degree of response. Finally, the pretransplant features significantly associated to CR were a low M-protein size (serum </=10 g/l and urine <0.5 g/24 h) (P=0.0003) and a proportion of bone marrow plasma cells of </=5% (P=0.02).

Hematopoietic stem cell transplantation for hematological malignancies in Europe

Hematopoietic stem cell transplants (HSCTs) are considered the best treatment option for many hematological malignancies, and transplant numbers have increased five-fold during the last decade. Only a few controlled prospective studies are available, and different opinions prevail. Data from 118 167 HSCT (36% allogeneic, 64% autologous) collected within the EBMT activity survey from 1990 to 2001 were used to assess trends over time, transplant rates and coefficient of variation (CV) of transplant rates among European countries for acute myeloid leukemia (AML; 18.5%), acute lymphocytic leukemia (ALL; 12%), chronic myeloid leukemia (CML; 11.5%), myelodysplastic syndromes (MDS; 3%), lymphoproliferative disorders (LPS; 36.3%) and multiple myeloma (MM; 18.7%). Transplant rates increased in all countries and for all indications from 1990 to 2001 from 1.7-fold (CML) to 24.8-fold (MM). Transplant rates have declined for CML since 1999. Autologous HSCT are the preferred choice for LPS and MM, allogeneic HSCT for ALL and myeloid malignancies. CVs of less than 50% suggest consensus for allogeneic HSCT in AML, ALL, CML, MDS and NHL, for autologous HSCT in LPS and MM. These data give an overview of the current status of HSCT for hematological malignancies in Europe and provide objective information for health-care providers and patient counselling.

Serial quantification of lymphoid and myeloid mixed chimerism using multiplex PCR amplification of short tandem repeat-markers predicts graft rejection and relapse, respectively, after allogeneic transplantation of CD34+ selected cells from peripheral blood

We used multiplex amplification of nine microsatellite sequences (PCR-STR) to analyse chimerism in pure populations of T cells and neutrophils from peripheral blood from 40 patients submitted to an allogeneic transplant, 22 having received a T-cell depleted (TCD) peripheral blood graft by means of CD34(+) selection (allo-PBT/CD34(+)), and 18, an unmodified graft (allo-SCT; 13 allogeneic bone marrow transplants and five allo-PBT). T-cell mixed chimerism (TcMC) was observed in 16 of the 22 (72.3%) patients receiving an allo-PBT/CD34(+), but in only one of the 18 (5.5%) patients receiving an allo-SCT (P=0.0001). TcMC was transient (n=6), stable (n=7), and associated with poor haematopoietic engraftment (n=4). All patients with TcMC who developed graft failure had more than 30% of host T cells. Myeloid MC (MyMC) was observed in four (19%) allo-PBT/CD34(+) patients and in three (17%) allo-SCT patients (P=NS). Five out of seven (71%) patients with MyMC relapsed, all of them diagnosed with myeloid malignancies, as compared with two of the 20 (10%) patients with complete donor chimerism (P&<0.0001). In conclusion, TcMC appears in a significant number of allo-PBT/CD34(+) patients and may be associated with poor engraftment when the percentage of host T cells is >30%; likewise, MyMC appears in a small percentage of recipients of both allo-PBT/CD34(+) and allo-SCT patients, and is associated with leukaemia relapse in myeloid malignancies.

Increasing use of reduced intensity conditioning transplants: report of the 2001 EBMT activity survey

Since 1990, the EBMT has annually collected numbers of HSCT by disease indication, donor type and stem cell source. The 2001 survey concentrates on the use of reduced intensity conditioning (RIC) transplants and its dissemination in Europe. In 2001, there were 19576 HSCT for new patients, 6413 with allogeneic HSCT (33%), 13163 with autologous HSCT (67%) and 3256 additional re- or multiple transplants, 868 (667/201) allogeneic and 2658 (537/2121) autologous, collected from 596 centers in 35 European countries. The main indications in 2001 were leukemias (32%; 73% of them allogeneic); lymphomas (53%; 92% of them autologous); solid tumors (11%; 93% of them autologous) and non-malignant disorders (4%; 90% of them allogeneic). Compared to 2000, there was a drop in allogeneic HSCT of over 20% for chronic myeloid leukemia and an increase of 2% in autologous HSCT. A total of 1759 or 27% of allogeneic transplants were reported as RIC HSCT. These have risen in number in 3 years from <1% in 1998. There are wide variations from 0 to 71% RIC HSCT in European countries with no obvious explanation. These data document the current status of blood and marrow transplantation in Europe and indicate a marked change towards RIC HSCT in allogeneic transplantation.

Hematopoietic stem cell transplantation in Europe 1998

INTRODUCTION

Transplantation of hematopoietic stem cells from blood or bone marrow has become accepted therapy for many diseases. Numbers of transplants have increased significantly and stem cell source, donor type and indications have changed during this decade. Information on these changes is essential for interpretation of current data, patient counseling and health care planning.

PATIENTS AND METHODS

Since 1990, members of the European Group for Blood and Marrow Transplantation and teams known to perform blood or marrow transplants have been invited annually to report their transplant numbers by indication, donor type and stem cell source. Data from these surveys have been used to present data for 1998, to assess current status and to give numbers of transplants per participating country, coefficients of variation between countries for individual indications and changes in indication, stem cell source and donor type over the past decade.

RESULTS

In 1998, a total of 20 892 transplants were performed by 528 teams in 31 European countries. Of these transplants 18 400 were first transplants, 5308 (29%) were allogenic, and 13 092 (71%) were autologous. Of the autologous transplants, 809 (6%) were bone marrow derived, and 12 283 (94%) were from peripheral blood stems cells. Of the allogeneic transplants, 3372 (64%) were bone marrow derived, and 1936 (36%) were peripheral blood stem cell transplants. In 1990, the respective figures were 2137 allogeneic (50%) and 2097 (50%) autologous transplants, all exclusively bone marrow derived. Main indications in 1998 were leukemias with 6015 transplants (33%), 68% thereof allogeneic transplants; lymphomas with 7492 transplants (41%), 94% thereof autologous transplants; solid tumors with 4025 transplants (22%), 99% thereof autologous transplants; non-malignant disorders with 868 transplants (5%), 80% thereof allogeneic transplants. Absolute numbers of transplants per year did increase from 4234 in 1990 to 20 892 in 1998. Increase is higher for autologous, than for allogeneic transplants. There were differences in absolute or relative increase over time for individual indications. Transplant rates per number of inhabitants varied between countries, ranging from 0 to >500 total transplants per 10 million inhabitants with a clear correlation between number of teams and transplants per 10 million inhabitants (r=0.61, P<0.001). The least variation between countries was observed for acute leukemias, chronic myeloid leukemia and severe aplastic anemia in allogeneic transplants, for Hodgkin's disease and non-Hodgkin's lymphoma in autologous transplants.

CONCLUSION

These data reflect the current status of blood and marrow transplantation in Europe. They show the continuing increase in utilization, highlight the change from bone marrow to blood as stem cell source and give an objective assessment on presence or absence of trends.

Allogeneic and autologous transplantation for haematological diseases, solid tumours and immune disorders: definitions and current practice in Europe

The Accreditation Sub-Committee of the EBMT regularly publishes special reports on current practice of haemopoietic stem cell transplantation for haematological diseases, solid tumours and immune disorders. Major changes have occurred since the last report in 1998. Haemopoietic stem cell transplantation today includes allogeneic and autologous stem cells derived from bone marrow, peripheral blood and cord blood. With reduced intensity conditioning regimens in allogeneic transplantation, the age limit has increased, permitting the inclusion of older patients. New indications have emerged, such as autoimmune disorders and AL amyloidosis for autologous, and solid tumours for allogeneic transplants. Other indications, such as autologous transplantation for breast cancer have been challenged. An updated report with revised tables and operating definitions is presented here.

Allogeneic transplantation of CD34(+) selected cells from peripheral blood from human leukocyte antigen-identical siblings: detrimental effect of a high number of donor CD34(+) cells?

Clinical results after T-cell-depleted allografts might be improved by modifying the graft content of progenitor and accessory cells. Although the association of the number of donor T cells with the clinical outcome has been studied extensively, the optimum number of progenitor cells that should be administered to patients is unknown. The characteristics of 84 consecutive human leukocyte antigen (HLA)-identical sibling transplants of granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood progenitor cells depleted of T cells by CD34(+) positive selection (allo-PBT/CD34(+)) were analyzed for their effect on clinical outcome. After a median follow-up of 24 months (range, 1-70 months), 50 patients remain alive (59.5%) and 34 have died (21 [25%] as a result of the transplant and 13 [15.5%] due to disease relapse). The median number of CD34(+) cells administered to the patients was 3.9 x 10(6)/kg (range, 1.2-14.3 x 10(6)/kg). A number of CD34(+) cells in the inoculum of 1 x 10(6)/kg to 3 x 10(6)/kg was associated with increased survival: 21 of 28 (75%) patients are alive, as compared with 29 of 56 (52%) patients receiving more than 3 x 10(6)/kg (actuarial probability 75% vs. 42%, respectively; P =.01). In the multivariate analysis, the independent prognostic variables for survival were CD34(+) cell dose 1 x 10(6)/kg to 3 x 10(6)/kg (RR = 4.8; P =.0008), sex-pairing match (RR = 3.2; P =.002), and early stage of disease (RR = 2.8; P =.007). From these results it appears that, in allo-PBT/CD34(+) from HLA-identical siblings, a number of CD34(+) cells in the inoculum between 1 x 10(6)/kg to 3 x 10(6)/kg is an important factor for better survival, and that higher CD34(+) cell doses might be associated with a poorer outcome.

Favourable effect of the combination of acute and chronic graft-versus-host disease on the outcome of allogeneic peripheral blood stem cell transplantation for advanced haematological malignancies

To assess the influence of graft-versus-host disease (GVHD) on the outcome of patients with advanced haematological malignancies (AHM) who received a primary, unmodified allogeneic peripheral blood progenitor cells transplant (allo-PBT) from a human leucocyte antigen (HLA) identical sibling donor, we analysed 136 patients with myeloid neoplasms (n = 70) or lymphoproliferative disorders (n = 66), transplanted at 19 Spanish institutions. Median age was 35 years (range 1-61). The cumulative incidence of relapse for all patients was 34% (95% CI, 26-42%), 41% (95% CI, 33-49) for patients without GVHD and 14% (95% CI, 3-25) (P = 0.001) for patients with acute and chronic GVHD. After a median follow-up of 11 months (range 2-49), 60 (44%) patients remained alive with an actuarial probability of overall survival and disease-free survival (DFS) at 30 months of 31% (95% CI, 21-41%) and 28% (95% CI, 17-39%) respectively. In patients surviving > 100 d, the low incidence of relapse in those with acute and chronic GVHD led to a DFS of 57% (95% CI, 38-76%) compared with a DFS of 34% (95% CI, 17-51%) in the remaining patients (P = 0.03). Our results indicate a reduced incidence of relapse for patients with AHM receiving an unmodified allo-PBT and developing acute and chronic GVHD, which results in an improved DFS.

Allogeneic transplantation of CD34+-selected cells from peripheral blood in patients with myeloid malignancies in early phase: a case control comparison with unmodified peripheral blood transplantation

An allogeneic transplantation of CD34(+)-selected cells from peripheral blood (allo-PBT/CD34(+)) from HLA-identical sibling donors was performed in 50 adult patients with acute myeloid leukemia in first complete remission (AML CR1) (n = 29), myelodysplastic syndrome (MDS) (n = 4), or chronic myeloid leukemia in first chronic phase (CML CP1) (n = 17). Clinical results were compared to a concurrent group of 50 patients transplanted with unmodified peripheral blood progenitor cells (allo-PBT), matched for age, diagnosis, and disease stage. The median follow-up period was 29 months (range 1-69). The actuarial probability of developing acute GVHD clinical grade II to IV was 16% (95%CI: 6-26) for the allo-PBT/CD34(+) group and 41% (95%CI: 29-57) for the allo-PBT group (P = 0.002). The actuarial probability of developing extensive chronic GVHD was 22% (95%CI: 8-36) for the allo-PBT/CD34(+) group and 47% (95%CI: 31-63) for the allo-PBT group (P = 0.02). Recipients of allo-PBT/CD34(+) had less toxicity associated with the transplant and better Karnofsky index at the last follow-up. For AML/MDS patients, the actuarial probability of disease-free survival (DFS) for recipients of allo-PBT/CD34(+) and allo-PBT was 65% (95%CI: 45-85) vs43% (95%CI: 28-58) (P = 0.05), respectively. These data provide a rationale for a randomised trial of allo-PBT/CD34(+) vs allo-PBT in AML/MDS patients in early stage of the disease.

Hematopoietic stem cell transplantation activity in Europe 1999

This survey on transplantation of hematopoietic stem cells from blood or bone marrow in Europe, the 10th in a series, reports the numbers of transplants performed in 1999 and concentrates on changes in indications and donor types. Members of the European Group for Blood and Marrow Transplantation and associated teams are invited every year to report their transplant numbers by indication, donor type and stem cell source. In 1999, a total 21 430 transplants were performed by 580 teams in 35 European countries. Of these transplants 18 720 were first transplants, 5879 (31%) allogeneic, 12 841 (69%) autologous; an additional 562 allogeneic and 2148 autologous transplants were re- or multiple transplants. Ninety-five percent of the autologous transplants and 45% of the allogeneic transplants were peripheral blood stem cell transplants. A total of 103, respectively 1.8% of the allogeneic transplants, were cord blood cell transplants. Main indications in 1999 were leukemias with 6289 transplants (34%), 70% thereof allogeneic transplants; lymphomas with 8219 transplants (44%), 92% thereof autologous transplants; solid tumors with 3302 transplants (18%), 99% thereof autologous transplants; nonmalignant disorders with 715 transplants (4%), 85% thereof allogeneic transplants. Absolute numbers of allogeneic transplants continued to increase as in previous years by 10%, in contrast, there was for the first time in 10 years a decrease in autologous transplants, mainly for solid tumors. Reasons therefore are discussed. These data reflect the most recent changes in utilisation and document current status of blood and marrow transplantation in Europe.

Allogenic stem cell transplantation as salvage therapy for patients relapsing after autologous transplantation: experience from a single institution

The prognosis of patients relapsing after an autologous transplant (autoSCT) is very poor. Allogenic stem cell transplantation (alloSCT) offers the possibility of curing some of these patients, at the cost, however, of a high transplant related mortality (TRM). The aim of this study was to analyze the outcome of 14 consecutive patients with hematologic malignancies, from a single institution, who underwent alloSCT for progressive disease after autoSCT. Patients had relapsed at a median of 11.5 months (range 2-72) after autoSCT and they underwent alloSCT at a median of 25.5 months (range 7-73) from the first transplant. Ten patients received HLA-identical related peripheral blood progenitor cells, three patients underwent matched-unrelated donor marrow transplants, and one patient received a mismatched related transplant. Conditioning regimens consisted of total body irradiation plus cyclophosphamide (n=5) or melphalan (n=1), or high-dose combination chemotherapy (n=8). Cyclosporin A and methotrexate were administered as graft-versus-host disease (GVHD) prophylaxis. Eight patients (57%) developed grade II-IV acute GVHD. All evaluable patients (n=6) presented extensive chronic GVHD. Overall survival at 1 year was 16% (median 3.5 months, 95% CI 0.7-10.3). Ten patients (71%) died from transplant related complications at a median of 3.5 months (range 0.7-11). Only one patient died of recurrent disease. Three patients remain alive and in complete remission at the time of this report (4, 20 and 20 months, respectively). In conclusion, alloSCT offers the possibility of a sustained control of the disease in some patients who relapse after an autoSCT. However, the procedure is associated with a high transplant-related mortality. Better results might be obtained by carefully selecting patients and by reducing the intensity of the preparative regimen.

The number of donor CD3(+) cells is the most important factor for graft failure after allogeneic transplantation of CD34(+) selected cells from peripheral blood from HLA-identical siblings

This study analyzed the characteristics of 257 HLA-identical sibling transplants of granulocyte colony-stimulating factor-mobilized peripheral blood progenitor cells depleted of T cells by CD34(+) positive selection (allo-PBT/CD34(+)) for their effect on the incidence of graft failure. Twenty-four patients developed graft failure (actuarial probability, 11%; 95% confidence interval, 7.1-14. 9). Prognostic factors considered were sex and age of donor and recipient, donor-recipient blood group compatibility, diagnosis, disease status at transplant, conditioning regimen, cytomegalovirus serology, number of CD34(+) and CD3(+) cells infused, and cryopreservation. The major factor associated with graft failure was the number of CD3(+) cells in the inoculum. Twenty-three of 155 patients receiving a T-cell dose in the graft less than or equal to 0.2 x 10(6)/kg experienced graft failure, compared with only one of 102 patients receiving more than 0.2 x 10(6)/kg (actuarial probability 18% vs 1%, respectively; P =.0001). The actuarial probability of graft failure progressively increased as the number of CD3(+) cells in the graft decreased, which was determined by grouping the number of CD3(+) cells in quartiles (log-rank P =.03; log-rank for trend P =.003). In the multivariate analysis by the proportional hazard method, 2 covariates entered into regression at a significant level: CD3(+) cells less than or equal to 0.2 x 10(6)/kg (risk ratio = 17; P <.0001), and patients with chronic myelogenous leukemia (CML) conditioned with busulphan-based regimens (risk ratio = 4.8; P =.001). From these results it appears that the number of CD3(+) cells in the inoculum-with a threshold of 0.2 x 10(6)/kg or less-is the most critical factor in maintaining a sustained engraftment in allo-PBT/CD34(+) from HLA-identical siblings. In addition, for patients with CML receiving 0.2 x 10(6)/kg or less CD3(+) cells, total body irradiation might be better than busulphan-based regimens.

High-dose therapy autotransplantation/intensification vs continued standard chemotherapy in multiple myeloma in first remission. Results of a non-randomized study from a single institution

The purpose of this study was to analyze the outcome of patients with multiple myeloma (MM) responding to initial chemotherapy who received intensification with high-dose therapy/autotransplantation (HDT) as compared to that of those who were continued on standard chemotherapy. From 1 January 1990 to 30 June 1998, 64 patients with MM who were younger than 65 years achieved a response to initial chemotherapy. Due to referral reasons, patients preference or inclusion in trials, 31 patients received HDT as early intensification while 33 were continued on standard chemotherapy. The presenting features were similar in both groups, except for the median age, which was lower in the HDT group (53 vs 58 years, P = 0.007). Complete response negative immunofixation - (CR) was achieved in 12 of 31 (39%) patients intensified with HDT and in two of 33 (6%) patients who were continued on conventional chemotherapy (P = 0.002). Event-free survival (EFS) was significantly longer in the HDT group (median, 43 vs 21 months; P = 0.007). Overall survival (OS) was not significantly different between groups (median, 62 vs 38 months; P = 0.21). However, patients in the HDT group who achieved CR had an EFS (median, 51 vs 31 months; P = 0.03) as well as an OS (median, not reached vs 50 months; P = 0.0006) significantly longer than those achieving a lower degree of response. In conclusion, this non-randomized study shows that early HDT increases CR rate and prolongs EFS. In addition, these results highlight CR as a crucial step for achieving long-lasting disease control and prolonged survival in patients with MM.

Patients with mantle-cell lymphoma relapsing after autologous stem cell transplantation may be rescued by allogeneic transplantation

Two patients with disseminated mantle-cell lymphoma relapsed 24 and 13 months, respectively, after high-dose chemotherapy and autologous stem cell transplantation (autoSCT). Both patients had an HLA-identical sibling and received an allogeneic stem cell transplant (alloSCT) 32 and 18 months after autologous transplant, after conditioning with fractionated 12 Gy total body irradiation plus cyclophosphamide 120 mg/kg. They are both alive and in complete remission 24 months after transplant. Both patients have developed chronic graft-versus-host disease and their Karnofsky performance status is 90%. AlloSCT may offer a useful approach in a subgroup of patients with mantle-cell lymphoma who have relapsed after autologous transplantation.

Complete remission of idiopathic myelofibrosis following donor lymphocyte infusion after failure of allogeneic transplantation: demonstration of a graft-versus-myelofibrosis effect

A patient with idiopathic myelofibrosis (IM) in the osteosclerotic phase received an allogeneic stem cell transplant. Hemopoietic engraftment was rapid, and full donor chimerism was observed on day +70. However, a few months later, replacement of donor hemopoiesis by the patient's 20q- cell clone was observed, followed by reappearance of the blood IM features, marrow fibrosis and osteosclerosis. At 8 months from transplant donor lymphocytes were infused, which induced chronic GVHD. This resulted in normalization of the blood, with disappearance of the fibrosis and osteosclerosis, effects which persisted 20 months later. This case provides evidence for a graft-versus-disease effect in IM.

Immune reconstitution following allogeneic peripheral blood progenitor cell transplantation

Delayed immune reconstitution following allogeneic stem cell transplantation remains a major clinical problem, resulting in significant transplant-related mortality from infectious complications. The recovery of immunity after bone marrow transplantation (BMT) is a complex process dependent on a large number of pre- and post-transplant factors. It has been suggested that the use of peripheral blood instead of bone marrow as stem cell source may accelerate immune reconstitution after allogeneic transplantation. Some authors have recently reported a more rapid recovery of the number and function of T and B cells after allogeneic peripheral blood progenitor cell transplant (allo-PBPCT) in comparison with conventional BMT, results which would reflect the high number of lymphocytes infused to the patients. Such a rapid immune recovery could indeed contribute to the apparent therapeutic advantage of PBPCT when compared with BMT. However, there is limited knowledge on this issue and randomized trials are required to prove whether allo-PBPCT is indeed superior to BMT in terms of immune reconstitution post-transplant. A review of some quantitative and functional aspects of immune recovery after allo-PBPCT is presented in this article.

Efficacy and toxicity of a high-dose G-CSF schedule for peripheral blood progenitor cell mobilization in healthy donors

An important issue in allogeneic peripheral blood progenitor cell transplantation is the optimization of the regimen of mobilization of progenitor cells from normal donors. It has been shown that for G-CSF doses up to 10 microg/kg/day, a dose-response relationship exists for the degree of progenitor cell mobilization. Formal comparisons with doses higher than 10 microg/kg/day, however, have not been reported. The aim of this study was to compare the mobilization and collection results of two different G-CSF (Filgrastim) schedules: 10 microg/kg/12 h (n = 20; group A) vs 10 microg/kg/24 h (n = 20; group B). Apheresis sessions were started on day 5 (after 4 days of G-CSF). Adverse events consisted of bone pain, headache, and fatigue which required treatment with acetaminophen +/- codeine in both donor groups. Discontinuation of G-CSF administration for intolerable side-effects was not necessary in any case. The increase in peripheral leukocyte and lymphocyte counts x 109/l on day 5 was higher in group A (56.2 (37.1-75.2) and 4.4 (2. 1-14.6), respectively) than in group B (27.5 (13.2-53.9) and 2.6 (1. 9-5.1), respectively) (P < 0.0001 and P = 0.008). Platelets x 109/l decreased in group A from 228 (161-286) before G-CSF administration to 207 (155-328) on day 5 (P = 0.03), whereas no change was observed in group B. Following the first apheresis, a significant decrease in platelet count was observed with both G-CSF schedules without any differences between groups. The number x 106/kg of both nucleated and CD34+ cells collected after the first apheresis session was higher in group A (672 (462-992) and 5.9 (3.4-10.4), respectively) than in group B (427 (319-608) and 3.1 (1.1-6.8), respectively) (P = 0.0003 in both cases). The median number of CD3+cells x 106/kg collected after one apheresis session was similar with both G-CSF schedules (212 (91-430) in group A and 170 (110-291) in group B) (P = NS). In conclusion, the schedule of 10 microg/kg/12 h was well tolerated and resulted in the collection of a higher number of progenitor cells than 10 microg/kg/24 h without increasing the T cell content. This approach could avoid the donor having to undergo a second apheresis, and facilitate further graft manipulation.

Phenotypic changes in neutrophil granulocytes of healthy donors after G-CSF administration

BACKGROUND AND OBJECTIVE

The aim of the present work was to analyze the immunophenotypic changes in neutrophil granulocytes (NG) and their evolution over time in 16 healthy donors who received G-CSF for stem cell mobilization for allogeneic peripheral blood stem cells (PBSC) transplantation.

DESIGN AND METHODS

The mobilization schedule consisted of G-CSF (Filgrastimq, Amgen) 10 microg/kg, s.c. for five consecutive days. Apheresis began 16-24h after the last dose of G-CSF. Immunophenotypic analysis (CD10, CD14, CD15, CD16, CD71, CD34 and HLA-DR) of NG and measurement of G-CSF serum levels were performed before G-CSF administration (day 0), on the fifth day of G-CSF treatment and days +7 and +30 after the last dose of G-CSF.

RESULTS

After G-CSF administration, peripheral blood NG presented increased expression of HLA-DR, CD34, CD14, and CD71, in addition to decreased expression of CD10 and CD15 and CD16 fluorescence mean intensity. The phenotypic changes on NG were parallel to serum G-CSF levels. All the phenotypic changes returned to the baseline values by one month after the end of G-CSF treatment. No changes were found in the expression of HLA-DR on T and B-lymphocytes.

INTERPRETATION AND CONCLUSIONS

These immunophenotypic changes suggest that after G-CSF administration NG from healthy donors who received G-CSF for stem cell mobilization carry transient features of immature phenotype and have increased functional activity.

[The autologous transplantation of hematopoietic precursors on an outpatient basis: an analysis of its feasibility at the Hospital Clínic de Barcelona]

BACKGROUND

Autologous stem cell transplantation (ASCT) is increasingly performed on an outpatient basis. Preliminary results show a significant financial saving without modifying the therapeutic results. The aim of this study has been to evaluate the feasibility of this procedure in our the Hospital Clínic of Barcelona, Spain.

PATIENTS AND METHODS

All patients in whom an ASCT due to a hematological malignancy, having a good performance status, a caregiver 24 h per day, a lodging near to the hospital and an appropriate cultural and social environment, were offered an outpatient management starting the day after stem cell administration (day +1).

RESULTS

During the study period (April, 1997-June, 1998) 64 ASCT were performed. Fifteen patients (23%) were managed on an outpatient basis. The remaining patients were not included in the study due to patient preference (26%), medical reasons (22%), distant home (18%) and social problems (9%). Seven patients (47%) had to be readmitted in the hospital due to fever (n = 4), nausea (n = 2) or respiratory distress (n = 1). Patients receiving total body radiation (TBI) in the conditioning regimen did not have a higher readmission rate than those conditioned without TBI. The median hospital stay (since day +1) was 6 (range: 0-22) and 17 (13-117) days for outpatient and inpatients respectively (p = 0.0016). This reduction would imply a saving of 65% in hospitalization charges and of 12% in total charges. All patients having elected the outpatient management were very satisfied by having made that choice.

CONCLUSION

With an appropriate patient selection, outpatient ASCT is a feasible method that may improve the quality of life of the patients and can reduce the costs of the procedure.