Survival improvements in adolescents and young adults after myeloablative allogeneic transplantation for acute lymphoblastic leukemia

Adolescents and young adults (AYAs, ages 15 to 40 years) with cancer have not experienced survival improvements to the same extent as younger and older patients. We compared changes in survival after myeloablative allogeneic hematopoietic cell transplantation (HCT) for acute lymphoblastic leukemia (ALL) among children (n = 981), AYAs (n = 1218), and older adults (n = 469) who underwent transplantation over 3 time periods: 1990 to 1995, 1996 to 2001, and 2002 to 2007. Five-year survival varied inversely with age group. Survival improved over time in AYAs and paralleled that seen in children; however, overall survival did not change over time for older adults. Survival improvements were primarily related to lower rates of early treatment-related mortality in the most recent era. For all cohorts, relapse rates did not change over time. A subset of 222 AYAs between the ages of 15 and 25 at 46 pediatric or 49 adult centers were also analyzed to describe differences by center type. In this subgroup, there were differences in transplantation practices among pediatric and adult centers, although HCT outcomes did not differ by center type. Survival for AYAs undergoing myeloablative allogeneic HCT for ALL improved at a similar rate as survival for children.

Significant improvement in survival after allogeneic hematopoietic cell transplantation during a period of significantly increased use, older recipient age, and use of unrelated donors

PURPOSE

Over the past four decades, allogeneic hematopoietic cell transplantation (alloHCT) has evolved as a curative modality for patients with hematologic diseases. This study describes changes in use, technique, and survival in a population-based cohort.

PATIENTS AND METHODS

The study included 38,060 patients with hematologic malignancies or disorders who underwent first alloHCT in a US or Canadian center from 1994 to 2005 and were reported to the Center for International Blood and Marrow Transplant Research.

RESULTS

AlloHCT as treatment for acute lymphoblastic (ALL) and myeloid leukemias (AML), myelodysplastic syndrome (MDS), and Hodgkin and non-Hodgkin lymphomas increased by 45%, from 2,520 to 3,668 patients annually. From 1994 to 2005, use of both peripheral (7% to 63%) [corrected] and cord blood increased (2% to 10%), whereas use of marrow decreased (90% to 27%). Despite a median age increase from 33 to 40 years and 165% [corrected] increase in unrelated donors for alloHCT, overall survival (OS) at day 100 significantly improved for patients with AML in first complete remission after myeloablative sibling alloHCT (85% to 94%; P < .001) and unrelated alloHCT (63% to 86%; P < .001); 1-year OS improved among those undergoing unrelated alloHCT (48% to 63%; P = .003) but not among those undergoing sibling alloHCT. Similar results were seen for ALL and MDS. Day-100 OS after cord blood alloHCT improved significantly from 60% to 78% (P < .001) for AML, ALL, MDS, and chronic myeloid leukemia. Use of reduced-intensity regimens increased, yielding OS rates similar to those of myeloablative regimens.

CONCLUSION

Survival for those undergoing alloHCT has significantly improved over time. However, new approaches are needed to further improve 1-year OS.

Trends in use of and survival after autologous hematopoietic cell transplantation in North America, 1995-2005: significant improvement in survival for lymphoma and myeloma during a period of increasing recipient age

Autologous hematopoietic cell transplantation (auto-HCT) is performed to treat relapsed and recurrent malignant disorders and as part of initial therapy for selected malignancies. This study evaluated changes in use, techniques, and survival in a population-based cohort of 68,404 patients who underwent first auto-HCT in a US or Canadian center between 1994 and 2005 and were reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). The mean annual number of auto-HCTs performed was highest during 1996-1999 (6948), and decreased subsequently 2000-2003 (4783), owing mainly to fewer auto-HCTs done to treat breast cancer. However, the mean annual number of auto-HCTs increased from 5278 annually in 1994-1995 to 5459 annually in 2004-2005, reflecting increased use for multiple myeloma, non-Hodgkin lymphoma, and Hodgkin lymphoma. Despite an increase in the median recipient age from 44 to 53 years, there has been a significant improvement in overall survival (OS) from 1994 to 2005 in patients with chemotherapy-sensitive relapsed non-Hodgkin lymphoma (day +100 OS, from 85% to 96%; 1-year OS, from 68% to 80%; P < .001) and chemotherapy-sensitive multiple myeloma (day +100 OS, from 96% to 98%; 1-year OS, from 83% to 92%; P < .001). This improvement in OS was most pronounced in middle-aged (>40 years) and older (>60 years) individuals.

Abandonment of high-dose chemotherapy/hematopoietic cell transplants for breast cancer following negative trial results

OBJECTIVE

In 1999, three randomized controlled trials concluded that high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (HDC/HCT) is no better than conventional chemotherapy for women with breast cancer. This study documents the impact of the trials on use of HDC/HCT and describes how hospitals reacted to the trials.

DATA SOURCE

We used patient-level data on 15,847 HDC/HCTs reported to the Center for International Blood and Marrow Transplant Research between 1994 and 2005.

STUDY DESIGN

We report trends in total HDC/HCT procedure volume, compare the time to hospitals' exit from the HDC/HCT market between research and nonresearch hospitals, and document trends in hospital-specific volumes in the 2 years before exit.

PRINCIPAL FINDINGS

HDC/HCT volume declined from 3,108 in 1998 to 1,363 the year after trial results were released. In 2002, only 76 procedures were performed. Teaching hospitals and the hospitals that participated in the trials were no slower to discontinue the procedure compared with nonteaching, nonparticipating hospitals. At the hospital level, volume declined steadily in the months before abandonment.

CONCLUSION

The results suggest that comparative effectiveness research studies that report negative results can reduce spending, but specialists may be reluctant to relinquish cutting-edge technologies.

Allogeneic transplants in follicular lymphoma: higher risk of disease progression after reduced-intensity compared to myeloablative conditioning

Reduced-intensity conditioning (RIC) regimens have been increasingly used for allogeneic hematopoietic stem cell transplantation (HSCT) in follicular lymphoma (FL). We compared traditional myeloablative conditioning regimens to RIC in FL. Outcomes of HLA-identical sibling HSCT for FL in 208 recipients reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) between 1997 and 2002 were studied. Conditioning regimens were categorized as myeloablative (N = 120) or RIC (N = 88). Use of RIC regimens increased from <10% of transplants in 1997 to >80% in 2002 signaling a major shift in practice. Patients receiving RIC were older and had a longer interval from diagnosis to transplant. These differences did not correlate with outcomes. Median follow-up of survivors was 50 months (4-96 months) after myeloablative conditioning versus 35 months (4-82 months) after RIC (P < .001). At 3 years, overall survival (OS) for the myeloablative and RIC cohorts were 71 (63%-79%) and 62 (51%-72%; P = .15) and progression free survival (PFS), 67 (58%-75%) and 55 (44%-65%; P = .07), respectively. Lower Karnofsky performance score (KPS) and resistance to chemotherapy were associated with higher treatment-related mortality (TRM) and lower OS and PFS. On multivariate analysis, an increased risk of lymphoma progression after RIC was observed (relative risk = 2.97, P = .04). RIC has become the de facto standard in allogeneic HSCT for FL, and appears to result in similar long-term outcomes. Although disease-free survival (DPS) is similar compared to myeloablative conditioning, an increased risk of late disease progression after RIC is concerning.

Granulocyte Colony-Stimulating Factor Mobilizes More Dendritic Cell Subsets Than Granulocyte-Macrophage Colony-Stimulating Factor with No Polarization of Dendritic Cell Subsets in Normal Donors

Dendritic cells (DCs) are effective antigen-presenting cells. We hypothesized that increasing the DC populations in donor lymphocyte infusions (DLIs) may augment the graft versus malignancy effect, particularly if granulocyte-macrophage colony-stimulating factor (GM-CSF) mobilization resulted in increased precursor dendritic cell (pDC) 1 cells. Mature DCs, pDC1 cells, pDC2 cells, and CD34(+) cells from the same donor were compared after granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood stem cell collections and GM-CSF mobilized DLI collections. Mobilization with G-CSF resulted in up to a 10-fold larger number of CD34(+) cells per kg and a 3-5-fold larger number of mature DCs, pDC1 cells, and pDC2 cells within the same donor compared with GM-CSF. The ratio of pDC1 to pDC2 in each donor remained constant with either cytokine. In this small sample of normal donors, it appears that G-CSF mobilizes more CD34(+) cells, mature DCs, pDC1 cells, and pDC2 cells within the same donor than does GM-CSF, with no significant polarization by G-CSF or GM-CSF for either pDC1 or pDC2 cells.

Denileukin diftitox for the treatment of steroid-resistant acute graft-versus-host disease

Acute graft-versus-host disease (aGVHD) is partly mediated through activated T cells, and these cells are known to express the high-affinity receptor for interleukin 2 (IL-2R). Denileukin diftitox is composed of human IL-2 and diphtheria toxin that is cytotoxic to activated lymphocytes expressing the high-affinity IL-2R. We describe the results of a phase II study of denileukin diftitox in 22 patients with steroid-resistant aGVHD. Twenty patients were treated at dose level 1 (4.5 microg/kg daily on days 1-5 and then weekly on study days 8, 15, 22, and 29), and 2 patients were treated at dose level 2 (9.0 microg/kg delivered on the same schedule). Dose level 2 was associated with grade 3/4 renal and hepatic toxicity and vascular leak syndrome, and no further patients were treated at this level. Dose level 1 was generally well tolerated. The response of aGVHD was assessed at study days 36 and 100. Nine patients (41%) responded, all with a complete response at study day 36, and 6 patients (27%) responded at study day 100 (4 complete responses and 2 partial responses). Denileukin diftitox has promising activity in steroid-resistant aGVHD, and further study is warranted.

Autologous transplantation for diffuse aggressive Non-Hodgkin lymphoma in first relapse or second remission

We evaluated the results of high-dose chemotherapy and autologous hematopoietic stem cell transplantation in patients with diffuse aggressive non-Hodgkin lymphoma (NHL) in first relapse (Rel 1) or second complete remission (CR 2). Data were evaluated from the Autologous Blood and Marrow Transplant Registry on 429 patients with diffuse aggressive NHL who underwent transplantation in Rel 1 or CR 2. Transplantations were performed between 1989 and 1996 and were reported to the Autologous Blood and Marrow Transplant Registry by 93 centers in North and South America. The probability of 3-year survival was 44% (95% confidence interval [CI], 33%-55%). The probability at 3 years of progression-free survival was 31% (95% CI, 27%-36%). Patients who underwent transplantation in CR 2 had a 3-year probability of progression-free survival of 38% (95% CI, 30%-46%) compared with 28% (95% CI, 22%-33%) for those who were not in remission at the time of transplantation (P <.001). In multivariate analysis, chemotherapy resistance, increased lactic dehydrogenase at diagnosis, an interval of <12 months from diagnosis to relapse, age >or=40 years, and use of myeloid growth factors to accelerate posttransplantation bone marrow recovery were adverse predictors of survival. High-dose chemotherapy and autologous hematopoietic stem cell transplantation for patients with diffuse aggressive NHL in CR 2 or Rel 1 resulted in better outcome for patients with chemotherapy-sensitive disease, longer relapse-free intervals, and age <40 years. Exposure to myeloid growth factors to accelerate recovery for recipients of bone marrow grafts may increase the risk of disease progression or death.

Ex vivo-expanded hematopoietic cell graft recipients exhibit T cell repertoire diversity similar to that seen after conventional stem cell transplants

The feasibility of using ex vivo-expanded hematopoietic progenitor cells to reconstitute hematopoiesis after high-dose chemotherapy is presently being examined. Early studies have shown that myeloid and erythroid hematopoiesis can be successfully reconstituted after high-dose chemotherapy and ex vivo-expanded hematopoietic cell transplantation. The lymphoid reconstitution, however, has not been addressed previously. In this study, we examined the diversity of the T cell receptor V beta chain (TCRBV) repertoires in 5 breast cancer patients who were transplanted with ex vivo-expanded bone marrow mononuclear cells as the only source of hematopoietic graft. Using the TCRBV third complementarity determining region (CDR3) fingerprinting methodology, it is shown that CD4(+) and CD8(+) T cell subsets after ex vivo-expanded hematopoietic cell graft transplants exhibit TCRBV diversities that are similar in complexity when compared to those seen after conventional autologous peripheral blood stem cell transplants (PBSCT). No apparent difference in the extent of CDR3 diversity was found between ex vivo expanded and conventional autologous PBSCT recipients when the CD4(+) and CD8(+) subsets were further separated into CD45RA(+) "naïve" and CD45RO(+) "memory" subsets. The diversity of the CD45RA(+) naïve subsets was as complex as that of the CD45RO(+) memory subsets. These results indicate that T cell repertoire diversification is not further compromised when ex vivo-expanded hematopoietic cells are used instead of autologous peripheral blood stem cells as the only source of graft.

High-dose melphalan allows durable engraftment of allogeneic bone marrow

Conditioning regimens for allogeneic bone marrow transplantation are designed to eradicate malignant cells and to provide sufficient immunosuppression for engraftment of donor marrow. Total body irradiation and high-dose cyclophosphamide are the most established immunosuppressive agents used for this purpose. It is uncertain whether other alkylating agent-based conditioning regimens are sufficiently immunosuppressive to allow engraftment of allogeneic marrow. We report four patients who had prompt engraftment after conditioning with melphalan-based chemotherapy regimens (BEAM or busulfan/melphalan). Two patients survived without disease for a prolonged period, indicating that these melphalan regimens are sufficiently immunosuppressive to allow sustained engraftment and donor hematopoiesis.