Five-year follow-up of patients with advanced chronic lymphocytic leukemia treated with allogeneic hematopoietic cell transplantation after nonmyeloablative conditioning

PURPOSE

We reported encouraging early results of allogeneic hematopoietic cell transplantation (HCT) after nonmyeloablative conditioning in 64 patients who had advanced chronic lymphocytic leukemia (CLL). Here, we have extended the follow-up to a median of 5 years and have included data on an additional 18 patients.

PATIENTS AND METHODS

Eighty-two patients, age 42 to 72 years, who had fludarabine-refractory CLL were conditioned with 2 Gy total-body irradiation alone or combined with fludarabine followed by HCT from related (n = 52) or unrelated (n = 30) donors.

RESULTS

Complete remission (CR) and partial remission were achieved in 55% and 15% of patients, respectively. Higher CR rates were noted after unrelated HCT (67% v 48%). The 5-year incidences of nonrelapse mortality (NRM), progression/relapse, overall survival, and progression-free survival were 23%, 38%, 50%, and 39%, respectively. Among 25 patients initially reported in CR, 8% relapsed and 8% died as a result of NRM, whereas 84% have remained alive and in CR. Among 14 responding patients who were tested and who had molecular eradication of their disease, two died as a result of NRM, two relapsed, and 10 have remained negative. At 5 years, 76% of living patients were entirely well, whereas 24% continued to receive immunosuppression for chronic graft-versus-host disease; the median performance status in each group was 100% and 90%, respectively. Lymphadenopathy > or = 5 cm, but not cytogenetic abnormalities at HCT, predicted relapse. In a risk-stratification model, patients who had lymphadenopathy less than 5 cm and no comorbidities had a 5-year OS of 71%.

CONCLUSION

Nonmyeloablative HCT resulted in a median survival of 5 years for patients who had fludarabine-refractory CLL with sustained remissions and in the continued resolution of chronic graft-versus-host disease in surviving patients.

Hematopoietic cell transplantation-comorbidity index and Karnofsky performance status are independent predictors of morbidity and mortality after allogeneic nonmyeloablative hematopoietic cell transplantation

BACKGROUND

Elderly and medically infirm cancer patients are increasingly offered allogeneic nonmyeloablative hematopoietic cell transplantation (HCT). A better understanding of the impact of health status on HCT outcomes is warranted. Herein, a recently developed HCT-specific comorbidity index (HCT-CI) was compared with a widely acceptable measure of health status, the Karnofsky performance status (KPS).

METHODS

The outcomes of 341 patients were evaluated, conditioned for either related or unrelated HCT by 2-gray (Gy) total body irradiation given alone or combined with fludarabine at a dose of 90 mg/m(2). Comorbidities were assessed retrospectively by the HCT-CI. Performance status before and toxicities after HCT were graded prospectively using the KPS and National Cancer Institute Common Toxicity criteria, respectively.

RESULTS

Weak Spearman rank correlations were noted between HCT-CI and KPS and between the 2 measures and age, number of prior chemotherapy regimens, and intervals between diagnosis and HCT (all r < 0.20). High-risk diseases correlated significantly with higher mean HCT-CI scores (P = .009) but not low KPS (P = .37). In multivariate models, the HCT-CI had significantly greater independent predictive power for toxicities (P = .004), nonrelapse mortality (P = .0002), and overall mortality (P = .0002) compared with the KPS (P = .05, .13, and .05, respectively). Using consolidated HCT-CI and KPS scores, patients were stratified into 4 risk groups with 2-year survivals of 68%, 58%, 41%, and 32%, respectively.

CONCLUSIONS

HCT-CI and KPS should be assessed simultaneously before HCT. The use of both tools combined likely refines risk-stratification for HCT outcomes. Novel guidelines for assessment of performance status among HCT patients are warranted.

Relapse risk in patients with malignant diseases given allogeneic hematopoietic cell transplantation after nonmyeloablative conditioning

Allogeneic hematopoietic cell transplantation (HCT) after nonmyeloablative conditioning for hematologic malignancies depends on graft-versus-tumor effects for eradication of cancer. Here, we estimated relapse risks according to disease characteristics. Between 1997 and 2006, 834 consecutive patients (median age, 55 years; range, 5-74 years) received related (n = 498) or unrelated (n = 336) HCT after 2 Gy total body irradiation alone (n = 171) or combined with fludarabine (90 mg/m(2); n = 663). Relapse rates per patient year (PY) at risk, corrected for follow-up and competing nonrelapse mortality, were calculated for 29 different diseases and stages. The overall relapse rate per PY was 0.36. Patients with chronic lymphocytic leukemia (CLL) and multiple myeloma (MM) in remission (CR), low-grade or mantle cell non-Hodgkin lymphoma (NHL) (CR + partial remission [PR]), and high-grade NHL-CR had the lowest rates (0.00-0.24; low risk). In contrast, patients with advanced myeloid and lymphoid malignancies had rates of more than 0.52 (high risk). Patients with lymphoproliferative diseases not in CR (except Hodgkin lymphoma and high-grade NHL) and myeloid malignancies in CR had rates of 0.26-0.37 (standard risk). In conclusion, patients with low-grade lymphoproliferative disorders experienced the lowest relapse rates, whereas patients with advanced myeloid and lymphoid malignancies had high relapse rates after nonmyeloablative HCT. The latter might benefit from cytoreductive treatment before HCT.

Extended mycophenolate mofetil and shortened cyclosporine failed to reduce graft-versus-host disease after unrelated hematopoietic cell transplantation with nonmyeloablative conditioning

We previously reported data from 103 patients with hematologic malignancies (median age 54 years) who received peripheral blood stem cell (PBSC) grafts from HLA-matched unrelated donors after nonmyeloablative conditioning and were given postgrafting immunosuppression consisting of mycophenolate mofetil (MMF; administered from day 0 until day +40 with taper through day +96) and cyclosporine (CSP; given from day -3 to day +100, with taper through day 180) (historical patients). The incidences of grade II-IV acute and extensive chronic graft-versus-host disease (aGVHD, cGVHD) were 52% and 49%, respectively, and the 1-year probabilities of relapse, nonrelapse mortality (NRM), and progression-free survival (PFS) were 26%, 18%, and 56%, respectively. Here, we treated 71 patients with hematologic malignancies (median age 56 years) with unrelated PBSC grafts and investigated whether postgrafting immunosuppression with an extended course of MMF, given at full dosing until day +150 and then tapered through day +180, and a shortened course of CSP, through day +80, would promote tolerance induction and reduce the incidence of GVHD (current patients). We observed 77% grade II-IV aGVHD and 45% extensive cGVHD (P=.03, and P=.43, respectively, in current compared to historical patients). The 1-year probabilities of relapse, NRM, and PFS were 23%, 29%, and 47%, respectively (P=.89, P=.02, and P=.08 compared to the historical patients). We conclude that postgrafting immunosuppression with extended MMF and shortened CSP failed to decrease the incidence of GVHD among unrelated PBSC recipients given nonmyeloablative conditioning.

High-dose immunosuppressive therapy and autologous hematopoietic cell transplantation for severe systemic sclerosis: long-term follow-up of the US multicenter pilot study

More effective therapeutic strategies are required for patients with poor-prognosis systemic sclerosis (SSc). A phase 2 single-arm study of high-dose immunosuppressive therapy (HDIT) and autologous CD34-selected hematopoietic cell transplantation (HCT) was conducted in 34 patients with diffuse cutaneous SSc. HDIT included total body irradiation (800 cGy) with lung shielding, cyclophosphamide (120 mg/kg), and equine antithymocyte globulin (90 mg/kg). Neutrophil and platelet counts were recovered by 9 (range, 7 to 13) and 11 (range, 7 to 25) days after HCT, respectively. Seventeen of 27 (63%) evaluable patients who survived at least 1 year after HDIT had sustained responses at a median follow-up of 4 (range, 1 to 8) years. There was a major improvement in skin (modified Rodnan skin score, -22.08; P < .001) and overall function (modified Health Assessment Questionnaire Disability Index, -1.03; P < .001) at final evaluation. Importantly, for the first time, biopsies confirmed a statistically significant decrease of dermal fibrosis compared with baseline (P < .001). Lung, heart, and kidney function, in general, remained clinically stable. There were 12 deaths during the study (transplantation-related, 8; SSc-related, 4). The estimated progression-free survival was 64% at 5 years. Sustained responses including a decrease in dermal fibrosis were observed exceeding those previously reported with other therapies. HDIT and autologous HCT for SSc should be evaluated in a randomized clinical trial.

Marking of peripheral T-lymphocytes by retroviral transduction and transplantation of CD34+ cells in a canine X-linked severe combined immunodeficiency model

A retrovirus vector containing an enhanced green fluorescent protein complimentary DNA (EGFP cDNA) was used to mark and dynamically follow vector-expressing cells in the peripheral blood of bone marrow transplanted X-linked severe combined immunodeficient dogs. CD34(+) cells isolated from young normal dogs were transduced, using a 2 day protocol, with an amphotropic retroviral vector that expressed enhanced green fluorescent protein (EGFP) and the canine common gamma chain (gammac) cDNAs. Following transplantation of the transduced cells, normal donor peripheral blood lymphocytes (PBL) appeared by 1 month post-bone marrow transplant (BMT) and rescued three of five treated dogs from their lethal immunodeficiency. PCR and flow cytometric analysis of post-BMT PBL documented the peripheral EGFP expressing cells as CD3(+) T cells, which varied from 0% to 28%. Sorting of EGFP(+) and EGFP(-) peripheral blood T cells from two dogs, followed by vector PCR analysis, showed no evidence of vector shutdown. EGFP expression in B cells or monocytes was not detected. These marking experiments demonstrate that the transduction protocol did not abolish the lymphoid engraftment capability of ex vivo transduced canine CD34(+) cells and supports the potential utility of the MSCV retroviral vector for gene transfer to XSCID affected canine hematopoietic progenitor cells (HPC).

Nonmyeloablative unrelated donor hematopoietic cell transplantation to treat patients with poor-risk, relapsed, or refractory multiple myeloma

The purpose of this study was to determine long-term outcome of unrelated donor nonmyeloablative hematopoietic cell transplantation (HCT) in patients with poor-risk multiple myeloma. A total of 24 patients were enrolled; 17 patients (71%) had chemotherapy-refractory disease, and 14 (58%) experienced disease relapse or progression after previous autologous transplantation. Thirteen patients underwent planned autologous transplantation followed 43-135 days later with unrelated transplantation, whereas 11 proceeded directly to unrelated transplantation. All 24 patients were treated with fludarabine (90 mg/m(2)) and 2 Gy of total body irradiation before HLA-matched unrelated peripheral blood stem cell transplantation. Postgrafting immunosuppression consisted of cyclosporine and mycophenolate mofetil. The median follow-up was 3 years after allografting. One patient experienced nonfatal graft rejection. The incidences of acute grades II and III and chronic graft-versus-host disease were 54%, 13%, and 75%, respectively. The 3-year nonrelapse mortality (NRM) was 21%. Complete responses were observed in 10 patients (42%); partial responses, in 4 (17%). At 3 years, overall survival (OS) and progression-free survival (PFS) rates were 61% and 33%, respectively. Patients receiving tandem autologous-unrelated transplantation had superior OS and PFS (77% and 51%) compared with patients proceeding directly to unrelated donor transplantation (44% and 11%) (PFS P value = .03). In summary, for patients with poor-risk, relapsed, or refractory multiple myeloma, cytoreductive autologous HCT followed by nonmyeloablative conditioning and unrelated HCT is an effective treatment approach, with low NRM, high complete remission rates, and prolonged disease-free survival.

Unrelated donor granulocyte colony-stimulating factor-mobilized peripheral blood mononuclear cell transplantation after nonmyeloablative conditioning: the effect of postgrafting mycophenolate mofetil dosing

We previously reported results in 71 patients with advanced hematologic malignancies given HLA-matched unrelated granulocyte colony-stimulating factor-mobilized peripheral blood mononuclear cell (G-PBMC) grafts after fludarabine 90 mg/m(2), 2 Gy of total body irradiation, and postgrafting mycophenolate mofetil (MMF) 15 mg/kg twice daily and cyclosporine 6.25 mg/kg twice daily orally. Graft rejection was 15%; the cumulative probability of acute graft-versus-host disease (GVHD) was 52%. According to MMF pharmacokinetic studies, which showed a short half-life of its active metabolite, mycophenolic acid, we increased MMF dosing from 15 mg/kg twice daily to 15 mg/kg 3 times daily to increase immunosuppression and reduce the incidence of both graft rejection and acute GVHD. Among 103 patients so treated, graft rejection occurred in 5%, whereas acute GVHD remained at 53%. Outcomes were compared with results of previous G-PBMC recipients given MMF twice daily. Infection rates were slightly higher with MMF 3 times daily than with MMF twice daily. Nevertheless, 2-year nonrelapse mortality and overall and progression-free survivals were similar for MMF 3-times-daily and twice-daily patients (19%, 58%, and 49% versus 20%, 48%, and 37%, respectively). Nonmyeloablative conditioning with postgrafting cyclosporine and MMF given 3 times daily allowed 95% durable engraftment of unrelated donor G-PBMC grafts.

Optimized Transduction of Canine Paediatric CD34+ Cells Using an MSCV-based Bicistronic Vector

We have used a murine MSCV-based bicistronic retroviral vector, containing the common gamma chain (gammac) and enhanced green fluorescent protein (EGFP) cDNAs, to optimize retroviral transduction of canine cells, including an adherent canine thymus fibroblast cell line, Cf2Th, as well as normal canine CD34(+) bone marrow (BM) cells. Both canine cell types were shown to express Ram-1 (the amphotropic retroviral receptor) mRNA. Supernatants containing infectious viruses were produced using both stable (PA317) and transient (Phoenix cells) amphotropic virus producer cell lines. Centrifugation (spinfection) combined with the addition of polybrene produced the highest transduction efficiencies, infecting approximately 75% of Cf2Th cells. An average of 11% of highly enriched canine CD34(+) cells could be transduced in a protocol that utilized spinfection and plates coated with the fibronectin fragment CH-296 (Retronectin). Indirect assays showed the vector-encoded canine gammac cDNA produced a gammac protein that was expressed on the cell surface of transduced cells. This strategy may result in the transduction of sufficient numbers of CD34(+) BM cells to make the treatment of canine X-linked severe combined immunodeficiency and other canine genetic diseases feasible.

Factors associated with outcomes in allogeneic hematopoietic cell transplantation with nonmyeloablative conditioning after failed myeloablative hematopoietic cell transplantation

PURPOSE

Several studies have investigated the feasibility of allogeneic hematopoietic cell transplantations (HCTs) after reduced-intensity conditioning in patients who experienced relapse after myeloablative HCT. Although most studies showed relatively low nonrelapse mortality (NRM) rates and encouraging short-term results, it has yet to be defined which patients would benefit most from these approaches.

PATIENTS AND METHODS

We analyzed data from 147 patients with hematologic malignancies who experienced treatment failure with conventional autologous (n = 135), allogeneic (n = 10), or syngeneic (n = 2) HCT and were treated with HLA-matched related (n = 62) or unrelated (n = 85) grafts after conditioning with 2 Gy of total-body irradiation with or without fludarabine.

RESULTS

Three-year probabilities of NRM, relapse, and overall survival were 32%, 48%, and 27%, respectively, for related recipients, and 28%, 44%, and 44%, respectively, for unrelated recipients. The best outcomes were observed in patients with non-Hodgkin's lymphoma, whereas patients with multiple myeloma and Hodgkin's disease had worse outcomes as a result of high incidences of relapse and progression. Being in partial remission (PR) or complete remission (CR) at HCT (P = .002) and developing chronic graft-versus-host disease (GVHD; P = .03) resulted in lower risks of relapse and progression. Factors associated with better overall survival were PR or CR (P = .01) and lack of comorbidity (P = .03) at HCT and absence of acute GVHD after HCT (P = .06).

CONCLUSION

Encouraging outcomes were seen with allogeneic HCT after nonmyeloablative conditioning in selected patients who had experienced relapse after a high-dose HCT, particularly in patients with non-Hodgkin's lymphoma. Results with unrelated grafts were comparable with results with related grafts.

Allogeneic marrow transplantation in patients with severe systemic sclerosis: resolution of dermal fibrosis

OBJECTIVE

To evaluate the safety and efficacy of allogeneic hematopoietic cell transplantation (HCT) after myeloablative conditioning in patients with severe systemic sclerosis (SSc).

METHODS

Eligibility criteria for the study included SSc patients with features indicative of a poor prognosis. The myeloablative conditioning regimen included busulfan, cyclophosphamide, and antithymocyte globulin. Prophylaxis for graft-versus-host disease (GVHD) consisted of cyclosporine and methotrexate. Bone marrow was transplanted from HLA-identical siblings.

RESULTS

Two patients with diffuse cutaneous SSc and lung involvement who were refractory to conventional immunosuppressive treatment were enrolled in the study. In patient 1, there were no complications related to the conditioning regimen, and GVHD did not develop after transplantation. At 5 years after HCT, there was nearly complete resolution of the scleroderma and marked improvement in physical functioning. Internal organ function improved (lung) or remained stable. On examination of serial skin biopsy samples, there was resolution of the dermal fibrosis. Patient 2 experienced skin toxicity from the conditioning regimen and hypertensive crisis that was likely related to high-dose corticosteroids given for treatment of GVHD. Although this patient experienced an improvement in scleroderma and overall functioning, a fatal opportunistic infection developed 17 months after HCT.

CONCLUSION

Allogeneic HCT may result in sustained remission of SSc. GVHD and opportunistic infections are the major risks associated with allogeneic HCT for SSc, as for allogeneic HCT in general.

Optimization of conditioning for marrow transplantation from unrelated donors for patients with aplastic anemia after failure of immunosuppressive therapy

In 87 patients with aplastic anemia who failed to respond to immunosuppressive treatment, we determined the minimal dose of total body irradiation (TBI) required when added to antithymocyte globulin (ATG, 30 mg/kg x 3) plus cyclophosphamide (CY, 50 mg/kg x 4) to achieve engraftment of unrelated donor marrow. TBI was started at 3 x 200 cGy, to be escalated or deescalated in steps of 200 cGy depending on graft failure or toxicity. Patients were aged 1.3 to 53.5 years (median, 18.6 years). The interval from diagnosis to transplantation was 3 to 328 months (median, 14.6 months). Donors were HLA-A, -B, -C, -DR, and -DQ identical for 62 patients, and nonidentical for 1 to 3 HLA loci at the antigen or allele level for 25. The dose-limiting toxicity was diffuse pulmonary injury. The optimum TBI dose was 1 x 200 cGy. Nine patients did not tolerate ATG and were prepared with CY + TBI. Graft failure occurred in 5% of patients. With a median follow-up of 7 years, 38 (61%) of 62 HLA-identical, and 10 (40%) of 25 HLA-nonidentical transplant recipients are surviving. The highest survival rate with HLA-identical transplants was observed at 200 cGy TBI. Thus, low-dose TBI + CY + ATG conditioning resulted in excellent outcome of unrelated transplants in patients with aplastic anemia who had received multiple transfusions.

Tacrolimus and mycophenolate mofetil after nonmyeloablative matched-sibling donor allogeneic stem-cell transplantations conditioned with fludarabine and low-dose total body irradiation

We evaluated tacrolimus/mycophenolate mofetil (MMF) for graft-versus-host disease (GVHD) prophylaxis after a nonmyeloablative stem cell transplantation (NST) from a matched sibling donor (MSD). Thirty-two patients (median age, 57 years) with advanced hematologic malignancies, who were poor candidates for a conventional myeloablative transplantation, received fludarabine (30 mg/m(2), day -4 to day -2), total-body irradiation (TBI) (200 cGy, day 0), infusion of donor peripheral blood progenitor cells (day 0), oral tacrolimus 0.06 mg/kg twice daily (from day 3), and oral MMF at 15 mg/kg twice daily (days 0-+27). Tacrolimus was tapered from day +100 to day +180 in those patients with indolent malignancies (n = 25), and from day +35 to day +56 in those with aggressive tumors (n = 7). Regimen toxicities and myelosuppression were mild, allowing 75% of patients to have entirely outpatient transplantations. One patient (3%) experienced a nonfatal graft rejection. Rates of grades II-IV and III-IV acute GVHD were 15.6% and 3%, respectively. Acute GVHD was diagnosed at median day +78 (range, days +31-+84). Extensive chronic GVHD was observed in 10 of 24 evaluable patients (41.6%) at a median onset of day +198 (range, days +128-+277), either spontaneously (n = 5) or elicited after tumor progression (n = 5). Five patients experienced transplantation-related mortality (TRM) (15.6%) from either acute GVHD-related multiorgan failure (MOF) (n = 3) or infectious complications (n = 2). At median follow-up of 19 months (range, 2-41 months), the overall survival, progression-free survival, and disease-free survival rates are 62.5%, 50%, and 40%, respectively. In conclusion, the use of tacrolimus/MMF after MSD NST is associated with encouraging rates of GVHD control.

Chronic kidney disease following non-myeloablative hematopoietic cell transplantation

Chronic kidney disease (CKD) following myeloablative allogeneic hematopoietic cell transplantation (HCT) occurs in 20% of survivors at 1 year and is believed to be due to radiation nephritis. Non-myeloablative allogeneic HCT is a recent procedure that employs significantly lower doses of chemoradiotherapy, however, incidence and risk factors for CKD following non-myleoablative HCT have not been defined. We performed a retrospective cohort study of 122 patients from three institutions who were available for analysis at 6 months following non-myeloablative HCT. Patients received two Gy of radiation; 62% received fludarabine as preconditioning. CKD was defined as at least a 25% reduction in glomerular filtration rate (GFR) from baseline using the abbreviated modified diet in renal disease (MDRD) equation. Eighty-one of 122 patients (66%) showed evidence of CKD at follow-up. Multivariate analysis revealed that acute renal failure (ARF) during the first 100 days post-transplant was associated with development of CKD (Adjusted OR 32.8 with 95% CI 4.3-250) after controlling for other variables. Previous autologous HCT, long-term calcineurin inhibitor use and extensive chronic GVHD were independently associated with CKD. CKD following non-myeloablative HCT appears to be a distinct clinical entity and likely not related to radiation nephritis. Future research should focus on possible mechanisms for alleviating chronic injury and decreasing use of calcineurin inhibitors.

Autologous transplantation followed closely by reduced-intensity allogeneic transplantation as consolidative immunotherapy in advanced lymphoma patients: a feasibility study

We report outcomes in advanced lymphoma patients (n = 32) who enrolled in a trial of prospectively planned combined autologous/reduced-intensity transplantation (RIT) (n = 25) or who received RIT shortly after prior autografting because of high relapse risk or progressive disease (n = 7). Nine patients on the autologous/RIT transplant protocol did not proceed to planned RIT because of patient choice (n = 4), disease progression (n = 3), toxicity (n = 1), or no adequate donor (n = 1). Among the 23 other patients, RIT was started a median of 59 days (range 31-123) after autologous transplant. Fifteen patients had related donors, five patients had unrelated donors, and three patients had cord blood donors. Among all patients completing RIT, the median overall survival time was 385 days (95% CI 272-792), and the median relapse-free survival time was 157 days (95% CI 119-385). At the time of reporting, six patients (26%) remain alive and three patients (13%) remain alive without relapse. The 100-day transplant-related mortality (TRM) was 9% among all patients and was 0% among matched sibling donors. Overall TRM was 43%. Tandem transplant is feasible in advanced lymphoma with low early TRM. However, practical challenges associated with the strategy were significant and high levels of late TRM due to graft-versus-host disease and infections suggest that modifications of the procedure will be needed to improve outcomes and patient retention.

HLA-matched unrelated donor hematopoietic cell transplantation after nonmyeloablative conditioning for patients with chronic myeloid leukemia

We evaluated 10/10 HLA antigen-matched unrelated hematopoietic cell transplantation (HCT) after nonmyeloablative conditioning with fludarabine 3 x 30 mg/m2 and 2 Gy of total body irradiation as treatment for patients with chronic myeloid leukemia who were ineligible for conventional HCT. Data from 21 consecutive patients in first chronic phase (CP1; n = 12), accelerated phase (AP; n = 5), second CP (CP2; n = 3), and blast crisis (n = 1) were analyzed. Stem cell sources were bone marrow (n = 4) or granulocyte colony-stimulating factor-mobilized peripheral blood mononuclear cells (G-PBMCs; n = 17). The patient who underwent transplantation in blast crisis died on day 21 (too early to be evaluated for engraftment) from progressive disease. Sustained engraftment was achieved in 5 of 12 patients who underwent transplantation in CP1, 4 of 5 patients who underwent transplantation in AP, and 2 of 3 patients who underwent transplantation in CP2, whereas 9 patients rejected their grafts between 28 and 400 days after HCT. Specifically, 1 of 4 marrow recipients and 10 of 17 G-PBMC recipients achieved sustained engraftment. Graft rejections were nonfatal in all cases and were followed by autologous reconstitution with persistence or recurrence of chronic myeloid leukemia. Seven of 11 patients with sustained engraftment--including all 5 patients in CP1, 2 of 4 patients in AP, and neither of the 2 patients in CP2--were alive in complete cytogenetic remissions 118 to 1205 days (median, 867 days) after HCT. Two of the remaining 4 patients died of nonrelapse causes in complete (n = 1) or major (n = 1) cytogenetic remissions, and 2 died of progressive disease. Further efforts are directed at reducing the risk of graft rejection by exclusive use of G-PBMC and increasing the degree of pretransplantation immunosuppression.

Phase I and pharmacokinetic study of docetaxel combined with melphalan and carboplatin, with autologous hematopoietic progenitor cell support, in patients with advanced refractory malignancies

The purpose of this study was to define the maximal tolerated dose (MTD), extramedullary toxicities, and pharmacokinetics of docetaxel combined with high-dose melphalan and carboplatin with autologous hematopoietic progenitor cell support. Fifty-nine patients with advanced refractory malignancy (32 breast cancer, 10 non-Hodgkin lymphoma, 6 germ cell tumors, 4 Hodgkin disease, 4 ovarian cancer, 2 sarcoma, and 1 unknown primary adenocarcinoma) with a median of 3 prior chemotherapy regimens and a median of 3 organs involved were enrolled. Treatment included docetaxel (150-550 mg/m2 infused over 2 hours on day -6), melphalan (150-165 mg/m2 infused over 15 minutes from day -5 to -3), and carboplatin (1000-1300 mg/m2 as a 72-hour continuous infusion from day -5). Five patients died from direct regimen-related organ toxicity (2 capillary leak syndrome, 2 enterocolitis, and 1 hepatic toxicity), and 1 additional patient died from pulmonary aspergillosis. The docetaxel MTD was defined as 400 mg/m 2 , combined with melphalan (150 mg/m2 ) and carboplatin (1000 mg/m2 ). The MTD cohort was expanded to enroll a total of 26 patients, 1 of whom died from toxic enterocolitis. The remaining 25 patients presented the following extramedullary toxicity profile, which was manageable and largely reversible: stomatitis, myoarthralgias, peripheral neuropathy, gastrointestinal and cutaneous toxicities, and syndrome of inappropriate antidiuretic hormone secretion. Docetaxel exhibited linear pharmacokinetics in the dose range tested (150-550 mg/m2 ). Pharmacodynamic correlations were noted between the docetaxel area under the curve and peripheral neuropathy or stomatitis. The response rate among 38 patients with measurable disease was 95%, with 47% complete responses. At a median follow-up of 26 months (range, 7-72 months), the 3-year event-free survival and overall survival were 26% and 36%, respectively. In conclusion, a 4-fold dose escalation of docetaxel, combined with melphalan and carboplatin, is feasible with autologous hematopoietic progenitor cell support. The notable activity of this regimen in treatment-refractory patients warrants its further evaluation.

Recovery from and consequences of severe iatrogenic lymphopenia (induced to treat autoimmune diseases)

To ascertain the consequences of severe leukopenia and the tempo of recovery, we studied the immunity of 56 adult patients treated for multiple sclerosis or systemic sclerosis with autologous CD34 cell transplantation using extremely lymphoablative conditioning. NK cell, monocyte, and neutrophil counts recovered to normal by 1 month; dendritic cell and B cell counts by 6 months; and T cell counts by 2 years posttransplant, although CD4 T cell counts remained borderline low. Initial peripheral expansion was robust for CD8 T cells but only moderate for CD4 T cells. Subsequent thymopoiesis was slow, especially in older patients. Importantly, levels of antibodies, including autoantibodies, did not drop substantially. Infections were frequent during the first 6 months, when all immune cells were deficient, and surprisingly rare (0.21 per patient year) at 7-24 months posttransplant, when only T cells (particularly CD4 T cells) were deficient. In conclusion, peripheral expansion of CD8 but not CD4 T cells is highly efficient. Prolonged CD4 lymphopenia is associated with relatively few infections, possibly due to antibodies produced by persisting pretransplant plasma cells.

Phase II feasibility and pharmacokinetic study of concurrent administration of trastuzumab and high-dose chemotherapy in advanced HER2+ breast cancer

PURPOSE

To evaluate the safety of concurrent treatment with trastuzumab and high-dose chemotherapy (HDC), using cyclophosphamide, cisplatin, and 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), with autologous hematopoietic progenitor cells support, in patients with HER2+ advanced breast cancer.

EXPERIMENTAL DESIGN

Patients with HER2-overexpressing high-risk primary breast cancer (HRPBC; defined as > or =4 involved nodes or inflammatory disease), or metastatic breast cancer (MBC) were eligible. Treatment consisted of a loading dose of trastuzumab at 4 mg/kg (day -5), HDC (days -5 to -2), autologous hematopoietic progenitor cells infusion on day 0, and weekly maintenance trastuzumab (2 mg/kg) from day +1 (minimum of 9 doses). Cardiac monitoring included serial left ventricular ejection fraction measurements before treatment and on days +20 and +65.

RESULTS

Thirty-three patients were prospectively enrolled (13 HRPBC, 20 MBC). Toxicity seemed similar to that expected with this HDC regimen alone. Neutrophils and platelets engrafted promptly. There were no cases of grade 4 or 5 toxicity. One patient experienced symptomatic grade 3 acute cardiac failure on day -4, responsive to treatment. Trastuzumab did not alter the pharmacokinetics of HDC. Eleven of twelve MBC patients with measurable disease (nine of them refractory to previous chemotherapy) experienced an objective response (9 complete and 2 partial responses). At median follow-up of 34 (13-58) months, all HRPBC patients remain alive and free of disease; the MBC group has event-free survival and overall survival rates of 45 and 70%, respectively.

CONCLUSIONS

Incorporation of trastuzumab into HDC (cyclophosphamide, cisplatin, and BCNU) is feasible, with no apparent increased toxicity or pharmacokinetic interactions.

Isolation and characterization of pediatric canine bone marrow CD34+ cells

Historically, the dog has been a valuable model for bone marrow transplantation studies, with many of the advances achieved in the dog being directly transferable to human clinical bone marrow transplantation protocols. In addition, dogs are also a source of many well-characterized homologues of human genetic diseases, making them an ideal large animal model in which to evaluate gene therapy protocols. It is generally accepted that progenitor cells for many human hematopoietic cell lineages reside in the CD34+ fraction of cells from bone marrow, cord blood, or peripheral blood. In addition, CD34+ cells are the current targets for human gene therapy of diseases involving the hematopoietic system. In this study, we have isolated and characterized highly enriched populations of canine CD34+ cells isolated from dogs 1 week to 3 months of age. Bone marrow isolated from 2- to 3-week-old dogs contained up to 18% CD34+ cells and this high percentage dropped sharply with age. In in vitro 6-day liquid suspension cultures, CD34+ cells harvested from 3-week-old dogs expanded almost two times more than those from 3-month-old dogs and the cells from younger dogs were also more responsive to human Flt-3 ligand (Flt3L). In culture, the percent and number of CD34+ cells from both ages of dogs dropped sharply between 2 and 4 days, although the number of CD34+ cells at day 6 of culture was higher for cells harvested from the younger dogs. CD34+ cells harvested from both ages of dogs had similar enrichment and depletion values in CFU-GM methylcellulose assays. Canine CD34+/Rho123lo cells expressed c-kit mRNA while the CD34+/Rhohi cells did not. When transplanted to a sub-lethally irradiated recipient, CD34+ cells from 1- to 3-week-old dogs gave rise to both myeloid and lymphoid lineages in the periphery. This study demonstrates that canine CD34+ bone marrow cells have similar in vitro and in vivo characteristics as human CD34+ cells. In addition, ontogeny-related functional differences reported for human CD34+ cells appear to exist in the dog as well, suggesting pediatric CD34+ cells may be better targets for gene transfer than adult bone marrow. The demonstration of similarities between canine and human CD34+ cells enhances the dog as a large, preclinical model to evaluate strategies for improving bone marrow transplantation protocols, for gene therapy protocols that target CD34+ cells, and to study the engraftment potential of various cell populations that may contain hematopoietic progenitor cell activity.

Prognostic analysis of early lymphocyte recovery in patients with advanced breast cancer receiving high-dose chemotherapy with an autologous hematopoietic progenitor cell transplant

PURPOSE

The purpose of this study was to evaluate the prognostic effect of early posttransplant lymphocyte recovery in patients with advanced breast cancer receiving high-dose chemotherapy with autologous hematopoietic progenitor cell transplantation.

EXPERIMENTAL DESIGN

We analyzed the effect of the absolute lymphocyte count on day +15 posttransplant on freedom from relapse and overall survival in patients with high-risk primary breast cancer or metastatic breast cancer, enrolled between 1990 and 2001 in prospective high-dose chemotherapy trials, using a uniform regimen of cyclophosphamide, cisplatin, and 1,3-bis(2-chloroethyl)-1-nitrosourea.

RESULTS

Four hundred and seventy-six patients (264 high-risk primary breast cancer and 212 metastatic breast cancer patients) were evaluated at median follow-up of 8 years (range, 1.5-11 years). The disease-free survival and overall survival rates in the high-risk primary breast cancer group were 67% and 70%, respectively. Patients with metastatic breast cancer patients had 21.8% disease-free survival and 31.5% overall survival rates. Day +15 absolute lymphocyte count correlated with freedom from relapse (P = 0.007) and overall survival (P = 0.04) in the metastatic breast cancer group, but not in the high-risk primary breast cancer group (P = 0.5 and 0.8, respectively). The prognostic effect of absolute lymphocyte count in metastatic breast cancer was restricted to those patients receiving unmanipulated peripheral blood progenitor cells (P = 0.04). In contrast, absolute lymphocyte count had no significant effect in those metastatic breast cancer patients receiving bone marrow or a CD34-selected product. In multivariate analyses, the prognostic effect of day +15 absolute lymphocyte count in metastatic breast cancer was independent of other predictors, such as disease status, pre-high-dose chemotherapy treatment, number of tumor sites, or HER2.

CONCLUSIONS

Early lymphocyte recovery is an independent outcome predictor in metastatic breast cancer patients receiving high-dose chemotherapy and an autologous peripheral blood progenitor cell transplant. These observations suggest that immune strategies targeting minimal posttransplant residual disease may prove worthwhile.