Outcomes of a Formal Hematopoietic Cell Transplantation Survivorship Program on Screening for Late Effects

Allogeneic hematopoietic cell transplantation (HCT) survivors may benefit from routine screening for post-transplant complications. However, the impact of formal survivorship efforts to promote screening adherence is uncertain. The effect of a formal HCT survivorship program to promote screening adherence was evaluated. We conducted a retrospective analysis of an academic formal HCT survivorship program with primary and specialty consult components. We included patients who underwent allogeneic HCT and were alive and relapse-free 1-year post-HCT. We excluded patients who died <2-year post-HCT or transferred care. We measured screening adherence to cardiovascular, pulmonary, ocular, secondary cancer, and endocrine evaluations. The primary outcome was proportion of patients completing ≥1 evaluation per screening domain prior to 2-year post-HCT. We examined screening adherence during 3 time periods: presurvivorship (2012 to 2014) and 2 postsurvivorship (2016 to 2018 and 2019 to 2021) using multivariate logistic and Cox proportional hazards regression. Four hundred ten patients (2012 to 2014: n = 136, 2016 to 2018: n = 153, 2019 to 2021: n = 121) were included. Compared to the presurvivorship period (16.9%), patients in 2016 to 2018 (47.7%, odds ratio [OR] = 4.9, P < .0001) and 2019 to 2021 (34.7%, OR = 2.7, P = .001) were more likely to complete ≥1 evaluation per screening domain. Except for pulmonary function tests in 2019 to 2021, median time to completion of survivorship evaluations was shorter in the survivorship periods compared to presurvivorship. Patients who completed a formal HCT survivorship consult in 2016 to 2018 and 2019 to 2021 were more likely to complete ≥1 evaluation per screening domain (OR = 5.1, P = .0004). Survivorship consult had similar effect on the primary screening outcome in 2016 to 2018 and 2019 to 2021 (consult × time interaction OR: 2.5, P = .2). However, patients who received a consult in 2019 to 2021 were more likely to complete all screenings (consult × time interaction: OR = 5.7, P = .03). Our HCT survivorship program with primary and specialty components improved screening adherence. Additional studies are needed to evaluate efficacy, dissemination, and implementation of formal HCT survivorship programs.

Safety and efficacy of tisagenlecleucel in primary CNS lymphoma: a phase 1/2 clinical trial

CD19-directed chimerical antigen receptor T-cell (CAR-T) products have gained US Food and Drug Administration approval for systemic large B-cell lymphoma. Because of concerns about potential immune cell-associated neurotoxicity syndrome (ICANS), patients with primary central nervous system (CNS) lymphoma (PCNSL) were excluded from all pivotal CAR-T studies. We conducted a phase 1/2 clinical trial of tisagenlecleucel in a highly refractory patients with PCNSL and significant unmet medical need. Here, we present results of 12 relapsed patients with PCNSL who were treated with tisagenlecleucel and followed for a median time of 12.2 months (range, 3.64-23.5). Grade 1 cytokine release syndrome was observed in 7/12 patients (58.3%), low-grade ICANS in 5/12 (41.6%) patients, and only 1 patient experienced grade 3 ICANS. Seven of 12 patients (58.3%) demonstrated response, including a complete response in 6/12 patients (50%). There were no treatment-related deaths. Three patients had ongoing complete remission at data cutoff. Tisagenlecleucel expanded in the peripheral blood and trafficked to the CNS. Exploratory analysis identified T-cell, CAR T, and macrophage gene signatures in cerebrospinal fluid following infusion when compared with baseline. Overall, tisagenlecleucel was well tolerated and resulted in a sustained remission in 3/7 (42.9%) of initial responders. These data suggest that tisagenlecleucel is safe and effective in this highly refractory patient population. This trial was registered at www.clinicaltrials.gov as #NCT02445248.

Ixazomib in addition to chemotherapy for the treatment of acute lymphoblastic leukemia in older adults

We sought to assess the safety of adding ixazomib, an oral proteasome inhibitor, to a multi-agent treatment regimen for older adults with acute lymphoblastic leukemia (ALL). Patients 51 to 75 years of age with newly diagnosed ALL were screened. Induction consisted of prednisone (P), vincristine (V), and doxorubicin (D). For BCR-ABL1+ patients, dasatinib was added. On Days 1, 8, 15 of induction, ixazomib was given orally. After induction patients received 1 cycle of consolidation in which ixazomib was given on Days 1, 8, 15. After consolidation, patients in remission (CR) were offered stem cell transplantation. Among the 19 patients treated, 15 (79%) [90% CI, 58-92%] achieved CR or CRi. At 2 years, the overall survival was 47% [95%CI, 29-72%]. In this study the dose of 2.3 mg of ixazomib in combination was the MTD for older patients with ALL and is the recommended dose for future phase 2 studies.

Arsenic toxicity manifesting as profuse watery diarrhea during induction therapy for acute promyelocytic leukemia

Arsenic trioxide (ATO) is generally well tolerated for treatment of APL. We present a patient with severe watery diarrhea and pancreatitis thought to be due to ATO toxicity in the setting of obesity and acute kidney injury. Future studies evaluating ATO levels in patients experiencing toxicities may help guide dose modifications.

Posttransplant cyclophosphamide in allogeneic bone marrow transplantation for the treatment of nonmalignant hematological diseases

We present a single-center retrospective series of allogeneic bone marrow transplantation (BMT) with the use of posttransplant cyclophosphamide (PTCy) in the setting of nonmalignant hematological conditions. Nine patients were treated between 2013 and 2019. Nonmyeloablative conditioning consisted of antithymocyte globulin, fludarabine, low-dose cyclophosphamide, and total body irradiation (200cGy) followed by allogeneic bone marrow infusion. Post-BMT GVHD prophylaxis was with PTCy, tacrolimus, and mycophenolate mofetil. At a median follow-up of 24 months (range 4, 63), all patients are alive, with donor-derived hematopoiesis and free of significant acute or chronic GVHD. Donors were haploidentical (n = 6), fully matched unrelated (n = 2), and fully matched sibling (n = 1). Neutrophil and platelet engraftment occurred at a median of 21 days and 33 days, respectively, after transplantation. Three patients (3/9, 33%) experienced stage 1-2 acute skin GVHD. The only cases of chronic GVHD are in three patients (3/9, 33%) with ocular disease (two mild, one moderate). No patient has required systemic immunosuppression beyond 12 months after BMT. PTCy-based nonmyeloablative allogeneic BMT is safe and effective for nonmalignant hematologic conditions and should be prospectively compared with historical regimens.

Hematopoietic Stem-Cell Transplantation in the Resource-Limited Setting: Establishing the First Bone Marrow Transplantation Unit in Bangladesh

PURPOSE

Treatment of malignant and nonmalignant hematologic diseases with hematopoietic stem-cell transplantation (HSCT) was first described almost 60 years ago, and its use has expanded significantly over the last 20 years. Whereas HSCT has become the standard of care for many patients in developed countries, the significant economic investment, infrastructure, and health care provider training that are required to provide such a service have prohibited it from being widely adopted, particularly in developing countries.

METHODS

Over the past two decades, however, efforts to bring HSCT to the developing world have increased, and several institutions have described their efforts to establish such a program. We aim to provide an overview of the current challenges and applications of HSCT in developing countries as well as to describe our experience in developing an HSCT program at Dhaka Medical College and Hospital in Bangladesh via a partnership with health care providers at Massachusetts General Hospital.

RESULTS AND CONCLUSION

We discuss key steps of the program, including the formation of a collaborative partnership, infrastructure development, human resource capacity building, and financial considerations.

Pilot study of a multimodal intervention to enhance sexual function in survivors of hematopoietic stem cell transplantation

BACKGROUND

Although sexual dysfunction is common after hematopoietic stem cell transplantation (HCT), interventions to address sexual function are lacking.

METHODS

We conducted a pilot study to assess the feasibility and preliminary efficacy of a multimodal intervention to address sexual dysfunction in allogeneic HCT survivors. Transplant clinicians screened HCT survivors ≥3 months post-HCT for sexual dysfunction causing distress. Those who screened positive attended monthly visits with a trained transplant clinician who: 1) performed an assessment of the causes of sexual dysfunction; 2) educated and empowered the patient to address his or her sexual concerns; and 3) implemented therapeutic interventions targeting the patient's needs. Feasibility was defined as having approximately 75% of patients who screened positive agreeing to participate and 80% attending at least 2 intervention visits. We administered the Patient-Reported Outcomes Measurement Information System (PROMIS) sexual function and satisfaction measure, the Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT), and the Hospital Anxiety and Depression Scale (HADS) to evaluate sexual function, quality of life (QOL), and mood, respectively, at baseline and 6 months postintervention.

RESULTS

Approximately 33.1% of patients (50 of 151 patients) screened positive for sexual dysfunction causing distress and 94.0% (47 of 50 patients) agreed to participate, with 100% attending 2 intervention visits. Participants reported improvements in satisfaction (P<.0001) and interest in sex (P<.0001), as well as orgasm (P<.0001), erectile function (P<.0001), vaginal lubrication (P = .0001), and vaginal discomfort (P = .0005). At baseline, approximately 32.6% of participants were not sexually active, compared with 6.5% after the intervention (P = .0005). Participants reported improvement in their QOL (P<.0001), depression (P = .0002), and anxiety (P = .0019).

CONCLUSIONS

A multimodal intervention to address sexual dysfunction integrated within the transplant clinic is feasible with encouraging preliminary efficacy for improving sexual function, QOL, and mood in HCT survivors. Cancer 2018;124:2438-46. © 2018 American Cancer Society.

Effect of Inpatient Palliative Care During Hematopoietic Stem-Cell Transplant on Psychological Distress 6 Months After Transplant: Results of a Randomized Clinical Trial

Purpose Inpatient palliative care integrated with transplant care improves patients' quality of life (QOL) and symptom burden during hematopoietic stem-cell transplant (HCT). We assessed patients' mood, post-traumatic stress disorder (PTSD) symptoms, and QOL 6 months post-transplant. Methods We randomly assigned 160 patients with hematologic malignancies who underwent autologous or allogeneic HCT to inpatient palliative care integrated with transplant care (n = 81) or transplant care alone (n = 79). At baseline and 6 months post-transplant, we assessed mood, PTSD symptoms, and QOL with the Hospital Anxiety and Depression Scale and Patient Health Questionnaire, PTSD checklist, and Functional Assessment of Cancer Therapy-Bone Marrow Transplant. To assess symptom burden during HCT, we used the Edmonton Symptom Assessment Scale. We used analysis of covariance while controlling for baseline values to examine intervention effects and conducted causal mediation analyses to examine whether symptom burden or mood during HCT mediated the effect of the intervention on 6-month outcomes. Results We enrolled 160 (86%) of 186 potentially eligible patients between August 2014 and January 2016. At 6 months post-transplant, intervention participants reported lower depression symptoms on the Hospital Anxiety and Depression Scale and Patient Health Questionnaire (adjusted mean difference, -1.21 [95% CI, -2.26 to -0.16; P = .024] and -1.63 [95% CI, -3.08 to -0.19; P = .027], respectively) and lower PTSD symptoms (adjusted mean difference, -4.02; 95% CI, -7.18 to -0.86; P = .013), but no difference in QOL or anxiety. Symptom burden and anxiety during HCT hospitalization partially mediated the effect of the intervention on depression and PTSD at 6 months post-transplant. Conclusion Inpatient palliative care integrated with transplant care leads to improvements in depression and PTSD symptoms at 6 months post-transplant. Reduction in symptom burden and anxiety during HCT partially accounts for the effect of the intervention on these outcomes.

Effect of Inpatient Palliative Care on Quality of Life 2 Weeks After Hematopoietic Stem Cell Transplantation: A Randomized Clinical Trial

IMPORTANCE

During hospitalization for hematopoietic stem cell transplantation (HCT), patients receive high-dose chemotherapy before transplantation and experience significant physical and psychological symptoms and poor quality of life (QOL).

OBJECTIVE

To assess the effect of inpatient palliative care on patient- and caregiver-reported outcomes during hospitalization for HCT and 3 months after transplantation.

DESIGN, SETTING, AND PARTICIPANTS

Nonblinded randomized clinical trial among 160 adults with hematologic malignancies undergoing autologous/allogeneic HCT and their caregivers (n = 94). The study was conducted from August 2014 to January 2016 in a Boston hospital; follow-up was completed in May 2016.

INTERVENTIONS

Patients assigned to the intervention (n=81) were seen by palliative care clinicians at least twice a week during HCT hospitalization; the palliative intervention was focused on management of physical and psychological symptoms. Patients assigned to standard transplant care (n=79) could be seen by palliative care clinicians on request.

MAIN OUTCOMES AND MEASURES

Primary: change in patient QOL from baseline to week 2; secondary: patient-assessed mood, fatigue, and symptom burden scores at baseline, 2 weeks, and 3 months after HCT and caregiver-assessed QOL and mood at baseline and 2 weeks after HCT.

RESULTS

Among 160 enrolled patients (mean age, 60 [SD, 13.3] years; 91 women [56.9%]; median hospital stay, 21 days) and 94 caregivers, 157 (98.1%) and 89 (94.7%), respectively, completed 2-week follow-up, and 149 patients (93.1%) completed 3-month follow-up. Patients in the intervention group reported a smaller decrease in QOL from baseline to week 2 (mean baseline score, 110.26; week 2 score, 95.46; mean change, -14.72) compared with patients in the control group (mean baseline score, 106.83; week 2 score, 85.42; mean change, -21.54; difference between groups, -6.82; 95% CI, -13.48 to -0.16; P = .045). Among the secondary outcomes, from baseline to week 2, patients in the intervention group vs those in the control group had less increase in depression (mean, 2.43 vs 3.94; mean difference, 1.52; 95% CI, 0.23-2.81; P = .02), lower anxiety (mean, -0.80 vs 1.12; mean difference, 1.92; 95% CI, 0.83-3.01; P < .001), no difference in fatigue (mean, -10.30 vs -13.65; mean difference, -3.34; 95% CI, -7.25 to 0.56; P = .09), and less increase in symptom burden (mean, 17.35 vs 23.14; mean difference, 5.80; 95% CI, 0.49-11.10; P = .03). At 3 months after HCT, intervention patients vs control patients had higher QOL scores (mean, 112.00 vs 106.66; mean difference, 5.34; 95% CI, 0.04-10.65; P = .048) and less depression symptoms (mean, 3.49 vs 5.19; mean difference, -1.70; 95% CI, -2.75 to -0.65; P = .002) but no significant differences in anxiety, fatigue, or symptom burden. From baseline to week 2 after HCT, caregivers of patients in the intervention group vs caregivers of patients in the control group reported no significant differences in QOL or anxiety but had a smaller increase in depression (mean, 0.25 vs 1.80; mean difference, 1.55; 95% CI, 0.14-2.96; P = .03).

CONCLUSIONS AND RELEVANCE

Among adults at a single institution undergoing HCT for hematologic malignancy, the use of inpatient palliative care compared with standard transplant care resulted in a smaller decrease in QOL 2 weeks after transplantation. Further research is needed for replication and to assess longer-term outcomes and cost implications.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02207322.

Phase II Trial of Tandem High-Dose Chemotherapy with Autologous Stem Cell Transplantation Followed by Reduced-Intensity Allogeneic Stem Cell Transplantation for Patients with High-Risk Lymphoma

Many patients with lymphoma relapse after autologous stem cell transplantation (AutoSCT). These patients are often considered for allogeneic stem cell transplantation (AlloSCT) if remission can be achieved. If a tandem approach was organized, some cases of relapse might be prevented. We conducted a phase II trial of tandem AutoSCT followed by reduced-intensity conditioning (RIC) AlloSCT for patients with high-risk lymphoma. High-dose chemotherapy was given with busulfan, cyclophosphamide, and etoposide. AlloSCT was composed of RIC with busulfan/fludarabine and tacrolimus, sirolimus, and methotrexate as graft-versus-host disease (GVHD) prophylaxis. Donors were fully matched related or unrelated donors. AlloSCT was performed any time between 40 days and 6 months after AutoSCT. Forty-two patients were enrolled, and all patients underwent AutoSCT. RIC AlloSCT was performed in 29 patients. In the 29 patients who underwent tandem transplant, median time from AutoSCT to AlloSCT was 96 days (range, 48 to 169). The 6-month cumulative incidence of grades II to IV acute GVHD was 13.8% (90% confidence interval [CI], 5.3% to 26.3%). Cumulative incidence of chronic GVHD at 1 year was 37.9% (90% CI, 23.1% to 52.7%). Nonrelapse mortality at 2 years after AlloSCT was 11.1% (90% CI, 3.5% to 23.6%). At a median follow-up of 30 months (range, 17.1 to 51.5) for the entire group, the 2-year progression-free survival rate was 64% (90% CI, 50% to 75%) and the 2-year overall survival rate was 69% (90% CI, 43% to 85%). For the 29 patients who underwent tandem SCT, the 2-year progression-free survival rate was 72% (90% CI, 55% to 83%) and the 2-year OS rate was 89% (90% CI, 74% to 96%). Tandem AutoSCT-RIC AlloSCT appears to be safe and effective in patients with high-risk lymphoma. Prospective trials using such an approach in specific lymphoma subtypes are warranted.

Prognostic understanding, quality of life and mood in patients undergoing hematopoietic stem cell transplantation

Little is known about how patients undergoing hematopoietic stem cell transplantation (HCT) and their family caregivers (FC) perceive their prognosis. We examined prognostic understanding in patients undergoing HCT and their FC and its relationship with quality of life (QOL) and mood. We conducted a longitudinal study of patients (and FC) hospitalized for HCT. We used a questionnaire to measure participants' prognostic understanding and asked the oncologists to estimate patients' prognosis prior to HCT. We assessed QOL and mood weekly and evaluated the relationship between prognostic understanding, and QOL and mood using multivariable linear mixed models. We enrolled 90 patients undergoing (autologous (n=30), myeloablative (n=30) or reduced intensity allogeneic (n=30)) HCT. About 88.9% of patients and 87.1% of FC reported it is 'extremely' or 'very' important to know about prognosis. However, 77.6% of patients and 71.7% of FC reported a discordance and more optimistic prognostic perception compared to the oncologist (P<0.0001). Patients with a concordant prognostic understanding with their oncologists reported worse QOL (β=-9.4, P=0.01) and greater depression at baseline (β=1.7, P=0.02) and over time ((β=1.2, P<0.0001). Therefore, Interventions are needed to improve prognostic understanding, while providing patients with adequate psychological support.

Phase I trial of maintenance sorafenib after allogeneic hematopoietic stem cell transplantation for fms-like tyrosine kinase 3 internal tandem duplication acute myeloid leukemia

The fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) mutation is associated with a high relapse rate for patients with acute myeloid leukemia (AML) even after allogeneic hematopoietic stem cell transplantation (HSCT). Sorafenib is a tyrosine kinase inhibitor, which inhibits the FLT3 tyrosine kinase and has shown encouraging activity in FLT3-ITD AML. We conducted a phase I trial of maintenance sorafenib after HSCT in patients with FLT3-ITD AML (ClinicalTrials.govNCT01398501). Patients received a variety of conditioning regimens and graft sources. A dose escalation 3 + 3 cohort design was used to define the maximum tolerated dose (MTD), with an additional 10 patients treated at the MTD. Sorafenib was initiated between days 45 and 120 after HSCT and continued for 12 28-day cycles. Twenty-two patients were enrolled (status at HSCT: first complete remission [CR1], n = 16; second complete remission [CR2], n = 3; refractory, n = 3). The MTD was established at 400 mg twice daily with 1 dose-limiting toxicity (DLT) observed (pericardial effusion). Two patients died of transplantation-related causes, both unrelated to sorafenib. Two patients stopped sorafenib after relapse and 5 stopped because of attributable toxicities after the DLT period. Median follow-up for surviving patients is 16.7 months after HSCT (range, 8.1 to 35.0). There was 1 case of grade II acute graft-versus-host disease (GVHD) after starting sorafenib and the 12-month cumulative incidence of chronic GVHD was 38% (90% confidence interval [CI], 21% to 56%). For all patients, 1-year progression-free survival (PFS) was 85% (90% CI, 66% to 94%) and 1-year overall survival (OS) was 95% (90% CI, 79% to 99%) after HSCT. For patients in CR1/CR2 before HSCT (n = 19), 1-year PFS was 95% (90% CI, 76% to 99%) and 1-year OS was 100%, with only 1 patient who relapsed. Sorafenib is safe after HSCT for FLT3-ITD AML and merits further investigation for the prevention of relapse.

Phase I dose escalation study of bortezomib in combination with lenalidomide in patients with myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML)

We conducted a phase I dose escalation study to determine the maximal tolerated dose of bortezomib that could be combined with standard dose lenalidomide in patients with MDS or AML. Treatment consisted of bortezomib (IV) on Days 1, 4, 8, and 11 and lenalidomide 10mg daily (PO) days 1-21 in 28 day cycles for up to 9 cycles. 23 patients (14 MDS/CMML, 9 AML) were enrolled. The maximally tested dose of bortezomib, 1.3mg/m(2), was tolerable in this regimen. Responses were seen in patients with MDS and AML. Further testing of this regimen is planned.

Phase II trial of parathyroid hormone after double umbilical cord blood transplantation

Transplantation of 1 or 2 umbilical cord blood products is a useful alternative stem cell source. However, the limited number of stem cells in each infusion results in slow engraftment. In mouse models, administration of parathyroid hormone (PTH) is an effective way to enhance the ability of limited numbers of hematopoietic stem cells to support hematopoiesis. In this study, patients received either a myeloablative or a reduced-intensity double umbilical cord blood transplantation, followed by PTH at 100 μg/day for 28 days. Thirteen patients (median age, 42 years) were enrolled. All patients engrafted; the median time to neutrophil and platelet engraftment of >20 × 10(9) cells/L was 30 days and 61 days, respectively. The incidence of grade II-IV acute GVHD was 38.5% at day 100. Four deaths occurred before day 100, prompting early study closure. No patient who received a myeloablative regimen relapsed. Overall survival at 6 months after transplantation was 62%, and disease-free survival at 2 years was 39%. At the dose and schedule studied, there was no evidence that PTH influenced blood count recovery.

Regulatory T-cell recovery in recipients of haploidentical nonmyeloablative hematopoietic cell transplantation with a humanized anti-CD2 mAb, MEDI-507, with or without fludarabine

OBJECTIVE

We have evaluated T-cell reconstitution and reactivity in patients receiving nonmyeloablative haploidentical hematopoietic cell transplantation (HCT) protocols involving an anti-CD2 monoclonal antibody (MEDI 507) to treat chemorefractory hematopoietic malignancies.

METHODS

Three cohorts of four patients each and one cohort of six patients received one of four Medi-507-based regimens, all of which included cyclophosphamide, thymic irradiation, and a short posttransplantation course of cyclosporine.

RESULTS

Following marked T-cell depletion, initially recovering CD4 and CD8 T cells were mainly memory-type cells. A high percentage of CD4 T cells expressed high levels of CD25 in recipients of all protocols, except the only protocol to include fludarabine, early post-HCT. CD25 expression varied inversely with T-cell concentrations in blood. CD25(high) CD4 T cells expressed Foxp3 and cytotoxic T-lymphocyte-associated protein 4, indicating that they were regulatory T cells (Treg).

CONCLUSIONS

Fludarabine treatment prevents Treg enrichment after haploidentical nonmyeloablative stem cell transplantation, presumably by depleting recipient Tregs. In vitro analyses of allorecognition were consistent with a cytokine-mediated rejection process in one case and in another provided proof of principle that mixed chimerism achieved without graft-vs-host disease induces donor- and recipient-specific tolerance. More reliable achievement of this outcome could provide a promising strategy for organ allograft tolerance induction.

Comparison of outcomes after transplantation of peripheral blood stem cells versus bone marrow following an identical nonmyeloablative conditioning regimen

This is the first study to examine the outcomes in 54 patients with hematologic malignancies who received an HLA-matched related donor bone marrow (BM, n = 42) or GCSF-mobilized peripheral blood stem cells (PBSC, n = 12) following identical nonmyeloablative conditioning with the intention of induction of mixed chimerism (MC) followed by prophylactic donor leukocyte infusion (pDLI) to convert MC to full donor chimerism (FDC) and capture a graft-versus-tumor effect without clinical graft-versus-host disease (GVHD). Neutrophil and platelet recovery were faster and transfusion requirement was less in PBSC recipients (P < 0.05). A total of 48% of BMT recipients achieved FDC with a median conversion time of 84 days, including 13 following pDLI. In contrast, 83% (P = 0.04) in the PBSC group had spontaneous FDC at a median of 14 days, precluding the administration of pDLI. There was no significant difference in the incidences of acute or chronic GVHD, though the rates of chronic GVHD were considerably higher in PBSC group than in the BM group (6/7, 86% vs 10/24, 42%). CD4 and CD8 T-cell recovery was faster in PBSC recipients. In PBSC recipients, a higher number of CD34+ cells was associated with increased rates of severe, grade III-IV acute GVHD.

Double unrelated reduced-intensity umbilical cord blood transplantation in adults

Umbilical cord blood (UBC) stem cells are a useful stem cell source for patients without matched related or unrelated donors. Adult transplantation with single UBC units is associated with high transplantation-related mortality (TRM). In most cases, mortality is due to infection related to slow engraftment and immunoincompetence. In this study, we used a reduced-intensity conditioning regimen of fludarabine, melphalan, and antithymocyte globulin followed by 2 partially matched UBC units. The UBC units were a 4/6 HLA match or better with each other and with the patient and achieved a minimum precryopreservation cell dose of 3.7 x 10(7) nucleated cells/kg. A total of 21 patients (median age, 49 years) were treated. The median time to an absolute neutrophil count > 0.5 x 10(9)/L was 20 days, and the median time to an unsupported platelet count > 20 x 10(9)/L was 41 days. Two patients experienced primary graft failure and underwent a second UBC transplantation. One patient had a late graft failure. Acute graft-versus-host disease (GVHD) grade II-IV occurred in 40% of patients. The 100-day TRM was 14%, and the 1-year disease-free survival was 67%. Mixed chimerism was associated with a higher risk of chronic GVHD. Our findings indicate that adult patients can tolerate double UBC transplantation well and achieve sustained antitumor responses using this reduced-intensity conditioning regimen.

Myeloma responses and tolerance following combined kidney and nonmyeloablative marrow transplantation: in vivo and in vitro analyses

Six patients with renal failure due to multiple myeloma (MM) received simultaneous kidney and bone marrow transplantation (BMT) from HLA-identical sibling donors following nonmyeloablative conditioning, including cyclophosphamide (CP), peritransplant antithymocyte globulin and thymic irradiation. Cyclosporine (CyA) was given for approximately 2 months posttransplant, followed by donor leukocyte infusions. All six patients accepted their kidney grafts long-term. Three patients lost detectable chimerism but accepted their kidney grafts off immunosuppression for 1.3 to >7 years. One such patient had strong antidonor cytotoxic T lymphocyte (CTL) responses in association with marrow rejection. Two patients achieved full donor chimerism, but resumed immunosuppression to treat graft-versus-host disease. Only one patient experienced rejection following CyA withdrawal. He responded to immunosuppression, which was later successfully withdrawn. The rejection episode was associated with antidonor Th reactivity. Patients showed CTL unresponsiveness to cultured donor renal tubular epithelial cells. Initially recovering T cells were memory cells and were enriched for CD4+CD25+ cells. Three patients are in sustained complete remissions of MM, despite loss of chimerism in two. Combined kidney/BMT with nonmyeloablative conditioning can achieve renal allograft tolerance and excellent myeloma responses, even in the presence of donor marrow rejection and antidonor alloresponses in vitro.

Anti-tumour response despite loss of donor chimaerism in patients treated with non-myeloablative conditioning and allogeneic stem cell transplantation

Based on a murine model, we conducted a series of trials of m-myeloablative human leucocyte antigen (HLA)-matched or mismatched related donor stem cell transplantation (SCT) with the intention of inducing mixed chimaerism (MC), then administering prophylactic donor lymphocyte infusions (DLIs), for the treatment of advanced haematologic malignancies. Preparative therapy consisted of cyclophosphamide, equine anti-thymocyte globulin (ATG) or MEDI-507 (an anti-CD2 monoclonal antibody) for in-vivo T-cell depletion, thymic irradiation on day -1 and cyclosporine alone for graft-versus-host disease (GVHD) prophylaxis. DLIs were given as early as 5 weeks post-SCT in patients with MC without evidence of GVHD. Twenty-two patients ultimately lost their graft (<1% donor cells) that could no be rescued by DLIs. Nine of 22 (41%) patients who lost donor chimaerism achieved an objective response, including three patients who showed evidence of disease regression following DLI, despite continued absence of macrochimaerism. Six patients were alive at 2.5-5.5 years following SCT, including four in continuous complete remission. In summary, it is possible to achieve sustained remission in patients with chemorefractory malignancies following non-myeloablative allogeneic SCT, even in the absence of sustained donor macrochimaerism; DLI may contribute to an ongoing anti-tumour effect in these patients. Immunological mechanisms that correlated with rejection of the graft may have a role in anti-tumour responses via a cell or cytokine-mediated pathway.

NK cell recovery, chimerism, function, and recognition in recipients of haploidentical hematopoietic cell transplantation following nonmyeloablative conditioning using a humanized anti-CD2 mAb, Medi-507

OBJECTIVE

Natural killer (NK) cells kill allogeneic cells that lack a class I MHC ligand for clonally distributed killer inhibitory receptors (KIR). Following HLA-mismatched hematopoietic cell transplantation (HCT), donor NK cells might mediate graft-vs-host (GVH) reactions that promote donor chimerism and mediate anti-tumor effects. Additionally, recipient NK cells might mediate donor marrow rejection. We have developed a nonmyeloablative approach to haploidentical HCT involving recipient treatment with a T cell-depleting mAb, Medi-507, that can achieve donor engraftment and mixed hematopoietic chimerism without graft-vs-host disease (GVHD). Donor lymphocyte infusions (DLI) are later administered in an effort to achieve graft-vs-leukemia/lymphoma (GVL) effects without GVHD. It is unknown whether NK cell "tolerance" develops in human mixed chimeras.

METHODS

We have addressed these issues in 12 patients receiving Medi-507-based nonmyeloablative haploidentical HCT.

RESULTS

NK cells recovered relatively early, despite the presence of circulating anti-CD2 mAb, but the majority of initially recovering cells lacked CD2 expression. These NK cells showed a reduced capacity, compared to those from normal donors, to kill class I-deficient targets. No association was detected between KIR mismatches in the host-vs-graft (HVG) or GVH direction and graft or tumor outcomes in this small series. NK cell chimerism did not correlate with chimerism in other lineages in mixed chimeras. NK cell tolerance to the host was not observed in a patient with full donor chimerism. One patient developed NK cell reactivity against donor-derived lymphoblast targets after loss of chimerism, despite the absence of an HVG KIR mismatch.

CONCLUSION

Our results do not show an impact of NK cells on the outcome of nonmyeloablative, even T cell-depleted, HCT across haplotype barriers using an anti-CD2 mAb. Our data also raise questions about the applicability of observations made with NK cell clones to the bulk NK cell repertoire in humans.

Early host CD8 T-cell recovery and sensitized anti-donor interleukin-2-producing and cytotoxic T-cell responses associated with marrow graft rejection following nonmyeloablative allogeneic bone marrow transplantation

OBJECTIVE

We developed a nonmyeloablative conditioning regimen for allogeneic bone marrow transplantation (BMT) followed by donor lymphocyte infusions (DLI) for treatment of chemotherapy refractory malignancies. Although the majority of patients who receive this regimen achieve lasting mixed or full allogeneic chimerism, approximately 30% show initial mixed chimerism followed by loss of the donor graft. These patients recover host hematopoiesis without significant cytopenias. To assess the role of immunologic rejection in graft loss, we compared T-cell recovery and in vitro alloresponses in six patients who lost their marrow graft to that in 16 concurrent patients with sustained donor chimerism.

PATIENTS AND METHODS

Conditioning included pretransplant cyclophosphamide (150-200 mg/kg), thymic irradiation (700 cGy), and pre- and post-transplant equine antithymocyte globulin (ATG; ATGAM). HLA-identical related donor BMT was followed by DLI at approximately day 35 in patients without graft-vs-host disease.

RESULTS

The group with transient chimerism showed significantly increased circulating host T-cell (median 416 cells/mm(3) vs 10 cells/mm(3), p<0.05) and CD8 T-cell numbers (354 cells/mm(3) vs 71 cells/mm(3), p<0.05) compared to the group with stable mixed or full donor chimerism within the first 100 days post-BMT. All DLI recipients who lost chimerism following DLI had greater than 80% recipient T cells at the time of DLI, whereas those with persistent chimerism had <60% host T cells. Graft rejection was associated with the development of a sensitized anti-donor bulk cytotoxic T-lymphocyte (CTL) response in 4 of 6 evaluated patients, compared to only 1 of 10 evaluated patients with sustained chimerism (p<0.05). Additionally, 3 of 5 evaluated transient chimeras showed high anti-donor CTL precursor frequencies in limiting dilution assays, and 3 of 4 evaluated transient chimeras showed high anti-donor interleukin-2 (IL-2)-producing T-helper (T(H)) cell frequencies. High anti-donor T(H) or cytotoxic T-lymphocyte precursors were not detected in sustained chimeras.

CONCLUSION

These data indicate that loss of chimerism in patients receiving this nonmyeloablative regimen is due to immune-mediated rejection. This rejection appears to bemediated by recovering recipient cytolytic CD8(+) cells as well as IL-2-producing recipient T(H) cells. These data are the first to demonstrate sensitization of recipient anti-donor IL-2-producing cells in association with human marrow allograft rejection.

Nonmyeloablative bone marrow transplantation: Infectious complications in 65 recipients of HLA-identical and mismatched transplants

Infections are a common complication of allogeneic bone marrow transplantation and the leading cause of transplantation-related mortality. It had been hypothesized that transplantation following nonmyeloablative preparative regimens would result in fewer infections by causing less mucosal injury, less graft-versus-host disease, and allowing earlier immune reconstitution. We have retrospectively reviewed the infectious complications of 65 consecutive patients with advanced hematologic malignancies who underwent bone marrow transplantation using a novel preparative regimen consisting of cyclophosphamide, thymic irradiation, and in vivo T-cell depletion. Cytomegalovirus (CMV) infection occurred in 52% of cases in which the donor or recipient had evidence of prior CMV exposure. Using a strategy of preemptive therapy and secondary prophylaxis with ganciclovir, no CMV disease occurred. Infections with gram-positive bacteria predominated over the first 100 days after bone marrow transplantation. Thereafter, the relative proportion of gram-negative infections increased without a significant increase in episodes of neutropenia. The rate of bacterial infections was not influenced by relapse of the underlying malignancy. Seven patients developed infections with Aspergillus species, which was the most common infectious cause of death in these patients. Infections with viruses other than CMV (n=10) and with protozoan organisms (n=2) also occurred. The use of HLA-mismatched donors, the occurrence of grade II-IV acute graft-versus-host disease, and treatment with corticosteroids did not influence the risk of CMV or bacterial or fungal infections in patients who underwent transplantation following this preparative regimen. Overall, the incidence and spectrum of infections in this series was similar to the reported incidence of infections following conventional myeloablative allogeneic stem cell transplantation. We conclude that a quantitative T-cell deficiency in these extensively T-cell depleted patients may be a risk factor for infection, even in the absence of graft-versus-host disease.

Impact of prophylactic donor leukocyte infusions on mixed chimerism, graft-versus-host disease, and antitumor response in patients with advanced hematologic malignancies treated with nonmyeloablative conditioning and allogeneic bone marrow transplantation

In an attempt to capture graft-versus-tumor effects without graft-versus-host disease (GVHD), the authors initiated a trial of nonmyeloablative allogeneic bone marrow transplantation (BMT) in patients with advanced hematologic malignancies, with the majority of patients having chemotherapy-refractory disease. Forty-two patients received an HLA-matched related donor BMT after a cyclophosphamide and antithymocyte globulin-based conditioning that also included thymic irradiation for patients who had not received prior mediastinal radiotherapy. Prophylactic donor leukocyte infusion (pDLI) at a dose of 1 x 10(7) CD3(+) cells per kilogram were given beginning 5 weeks post-BMT to 16 patients with mixed chimerism (MC) but without GVHD, whereas 26 patients did not receive pDLI, either because of GVHD or early relapse. Twelve of 16 patients (75%) receiving pDLI had T cell chimerism at the time of pDLI >/=40%. These patients, by day 100 post-BMT, either converted to full donor chimerism (FDC) (n = 10) or had an increase in or stable donor chimerism (n = 2) after pDLI. Four of 4 patients whose T cell chimerism was </=20% at the time of pDLI, lost the graft. In contrast, only 5 of 18 evaluable patients (28%) not receiving a pDLI converted to FDC by day 100 post-BMT, 7 maintained MC, and 10 of an evaluable 22 lost the graft. Patients who had undergone a previous autologous stem cell transplant had a higher rate of conversion to FDC (69% v 31%) and higher incidence of GVHD (69% v 34%) compared with those who did not have a previous autologous SCT. Eleven of 16 patients (69%) who received a pDLI achieved a remission with 50% 1-year progression-free survival rate and 44% 3-year overall survival rate. Nineteen of 42 patients (45%) had >/=grade II acute GVHD, including 12 after BMT and 7 after pDLI. Approximately one third of patients, after having initial MC, eventually lost their donor graft. The authors conclude that (1) pDLI has the potential to convert MC to FDC; (2) sustained remissions can be achieved in patients with chemorefractory hematologic malignancies who receive a pDLI, albeit with a significant risk of acute GVHD; and (3) the degree of donor T cell chimerism at the time of pDLI is predictive of the fate of MC, ie, donor T cell chimerism >/=40% or </=20% at the time of pDLI correlates with conversion of MC or loss of the graft, respectively.

Induction of kidney allograft tolerance after transient lymphohematopoietic chimerism in patients with multiple myeloma and end-stage renal disease

BACKGROUND

Two patients with end-stage renal disease secondary to multiple myelomas were treated with combined kidney and bone marrow transplantation in an effort to achieve donor-specific allotolerance through the induction of mixed lymphohematopoietic chimerism.

METHODS

Two female patients (55 and 50 years of age) with end-stage renal disease secondary to kappa light-chain multiple myelomas received a nonmyeloablative conditioning regimen that consisted of 60 mg/kg cyclophosphamide intravenously (IV) on days -5 and -4; 15 mg/kg equine anti-thymocyte globulin (ATGAM) IV on days -1, +1, and +3; and thymic irradiation (700 cGy) on day -1. On day 0, the recipients underwent kidney transplantation, followed by IV infusion of donor bone marrow (2.7x10(8) and 3.8x10(8) /kg nucleated cells, respectively) obtained from a human leukocyte antigen (HLA)-matched sibling. Cyclosporine A was administered IV at a dose of 5 mg/kg on day -1, then continued orally at 8 to 12 mg/kg per day until days +73 and +77, respectively, after which no further immunosuppression was given. Donor leukocyte infusions (1x10(7) /kg CD3+ T cells) were administered in an attempt to enhance the graft-versus-myeloma effect (days +66 and +112 in the first patient and day +78 in the second patient). Hematopoietic chimerism was monitored weekly by microsatellite assays.

RESULTS

Multilineage lymphohematopoietic chimerism (5%-80% donor CD3+ or CD3- cells, or both) was first detected during the second posttransplant week and was maintained for approximately 12 weeks, after which there was a gradual decline to undetectable levels (<1% donor cells) after day 105 in the first patient and after day 123 in the second patient. In both recipients, the blood urea nitrogen and creatinine levels returned to normal within 3 days. No rejection episodes have occurred. Quantification of urinary kappa light chains revealed a decline from 28 mg/dL to undetectable levels (<2.5 mg/dL) within 29 days in the first case and from 99.8 mg/dL to <10 mg/dL within 50 days in the second case. Both patients continue with normal kidney function and sustained anti-tumor responses, while receiving no immunosuppression for nearly 4 years and 2 years, respectively.

CONCLUSIONS

This nonmyeloablative regimen followed by combined HLA-matched donor bone marrow and renal allotransplantation is the first example of an intentional and clinically applicable approach to inducing renal allograft tolerance and achieving potent and sustained antitumor effects in patients with multiple myeloma.

Successful allogeneic stem cell transplantation with nonmyeloablative conditioning in patients with relapsed hematologic malignancy following autologous stem cell transplantation

The use of myeloablative preparative therapy and allogeneic stem cell transplantation (alloSCT) as salvage therapy for adult patients with relapsed hematologic malignancy after autologous stem cell transplantation (autoSCT) is generally unsuccessful due to very high treatment-related mortality rates. We evaluated the outcome of HLA-matched related donor alloSCT following nonmyeloablative preparative therapy in 13 patients (median age, 38 years) with relapsed hematologic malignancies (Hodgkin's disease, n = 4; Hodgkin's disease and advanced myelodysplastic syndrome, n = 1; non-Hodgkin's lymphoma, n = 6; multiple myeloma, n = 2) after initial autoSCT. Median time from autoSCT to alloSCT was 12 months (range, 3-24 months); 6 patients had chemotherapy-refractory disease following autoSCT, 6 were in untreated relapse, and 1 had a partial response from salvage chemotherapy. Preparative therapy consisted of cyclophosphamide, 150-200 mg/kg; peritransplantation anti-thymocyte globulin; thymic irradiation (in patients who had not received previous mediastinal irradiation); and a very short course of cyclosporine as GVHD prophylaxis. All patients achieved initial mixed chimerism as defined by greater than 1% donor peripheral white blood cells. Seven patients, who had no evidence of GVHD, received prophylactic DLI beginning 5 to 6 weeks after transplantation for conversion of mixed chimerism to full donor hematopoiesis and to optimize a graft-versus-tumor effect. Six patients showed conversion to full donor chimerism and 1 lost the graft. Grade II or greater acute GVHD occurred in 9 patients. Seven patients achieved a complete response; 6 had no response. The median survival time of the 13 patients is currently 10 months (range, 3-39 months), with an overall survival probability at 2 years of 45% (95% confidence interval [CI], 19%-73%) and a disease-free survival probability at 2 years of 37.5% (95% CI, 12%-65%). Thus, this novel nonmyeloablative alloSCT strategy followed by prophylactic DLI was well tolerated and can result in durable disease-free survival among patients with advanced hematologic malignancies after a failed autoSCT. Further follow-up and evaluation of additional patients are required to conclusively establish the role of this strategy in the treatment of hematologic malignancies after an autologous transplantation.

Successful pregnancy after high-dose cyclophosphamide, carboplatinum, and taxol with peripheral blood stem cell transplant in a young woman with ovarian carcinoma

BACKGROUND

Both ovarian carcinoma and high-dose chemotherapy tend to preclude future pregnancies.

CASE

We report a case of a young woman with borderline ovarian carcinoma and invasive tumor implants who underwent surgical debulking with preservation of future fertility followed by carboplatinum, paclitaxel (Taxol), and subsequent high-dose chemotherapy with subsequent peripheral blood stem cell rescue as part of a phase I clinical trial. After a brief period of amenorrhea, the patient had a successful pregnancy that was complicated by a spontaneous abortion in the first trimester. Several months later she conceived and delivered a healthy baby at term.

CONCLUSIONS

To our knowledge this is the first reported case of pregnancy after high-dose chemotherapy with stem cell transplant in a woman with ovarian carcinoma.

Intentional induction of mixed chimerism and achievement of antitumor responses after nonmyeloablative conditioning therapy and HLA-matched donor bone marrow transplantation for refractory hematologic malignancies

Mixed lymphohematopoietic chimerism can be induced in mice with bone marrow transplantation (BMT) after a nonmyeloablative preparative regimen that includes cyclophosphamide, anti-T-cell antibody therapy, and thymic irradiation. These mixed chimeras are resistant to the induction of graft-versus-host disease (GVHD) after delayed donor leukocyte infusions (DLIs), despite a potent lymphohematopoietic graft-versus-host reaction that converts the mixed chimeric state to a full donor one. Based on this animal model, we initiated a trial of nonmyeloablative therapy with HLA-matched or -mismatched donor BMT and DLI for refractory hematologic malignancies. Twenty-one of 36 patients enrolled in this trial received a genotypically (n = 20) or phenotypically (n = 1) HLA-matched donor transplant; results reported here are for those patients only. Preparative therapy consisted of cyclophosphamide in doses of 150 to 200 mg/kg; peritransplant antithymocyte globulin; thymic irradiation (in patients who had not received previous mediastinal radiation therapy); and cyclosporine. Eighteen of 20 evaluable patients developed persistent mixed lymphohematopoietic chimerism as defined by >1% donor peripheral white blood cells until at least day 35 posttransplantation. Ten patients received prophylactic DLI beginning 5 to 6 weeks after BMT for conversion of mixed chimerism to full donor hematopoiesis and to optimize a graft-versus-leukemia effect. Fourteen of 20 evaluable patients (70%) achieved an antitumor response; 8 of these responses were complete, and 6 were partial. Of the 8 evaluable patients who received prophylactic DLI, 6 showed conversion to full donor chimerism. Five of the 9 evaluable patients (56%) who received prophylactic DLI achieved a complete response, compared with 3 of 11 patients (27%) who did not receive prophylactic DLI. Currently 11 patients are alive, and 7 of these are free of disease progression at a median follow-up time of 445 days (range, 105-548 days) posttransplantation. Transplantation-related complications included cyclophosphamide-induced cardiac toxicity in 3 of 21 patients (14%) and grade II or greater GVHD in 6 patients (29%). One patient (5%) died from a complication of BMT, and 1 patient (5%) died from GVHD after 2 prophylactic DLIs were given for conversion of chimerism. In summary, mixed lymphohematopoietic chimerism was reproducibly induced after a novel nonmyeloablative preparative regimen incorporating chemotherapy, peritransplant antithymocyte globulin, and thymic irradiation, allowing for early administration of DLI in 10 of 21 patients. After treatment, striking antitumor responses were observed in the majority of patients with chemotherapy-refractory hematologic malignancies.

A prospective randomized trial comparing the toxicity and safety of atovaquone with trimethoprim/sulfamethoxazole as Pneumocystis carinii pneumonia prophylaxis following autologous peripheral blood stem cell transplantation

Pneumonia due to Pneumocystis carinii is an infrequent complication following autologous stem cell transplantation (ASCT) which is associated with a high mortality. Although administration of trimethoprim/sulfa- methoxazole (TMP/SMX) is an effective prophylactic strategy for Pneumocystis carinii pneumonia (PCP), treatment-associated toxicity frequently results in discontinuation of therapy. We have conducted a prospective randomized trial comparing atovaquone, a new anti-Pneumocystis agent, with TMP/SMX for PCP prophylaxis following autologous peripheral blood stem cell (PBSC) transplantation. Thirty-nine patients were studied. Twenty patients received atovaquone suspension and 19 patients received TMP/SMX. The median ages were 44 (range 20-68) and 47 (range 32-63) years, respectively. A similar number of patients with solid tumors (14 vs 15) and hematologic malignancies (five vs five) were treated in each group. Either TMP/SMX (160/800 mg) or atovaquone (1500 mg) was administered daily from transplant day -5 until day -1, discontinued from day 0 to engraftment, then resumed 3 days per week until day +100 post-transplant. The median time to engraftment (ANC >0.5 x 109/l) was similar in both groups. Eighty percent of the patients randomized to atovaquone prophylaxis completed the study. Four atovaquone-treated patients were removed from study; two patients (10%) did not receive a transplant and two patients (10%) were removed due to a protocol violation. None of the 16 patients treated with atovaquone experienced treatment-associated adverse effects. Of the 19 patients randomized to receive TMP/SMX, 55% completed the study. Nine TMP/SMX-treated patients were removed from the study; one patient (5%) did not receive a transplant and eight patients (40%) were removed due to drug intolerance (P < 0.003). The rate of intolerance to TMP/SMX led to the early discontinuation of this randomized trial. Intolerance of TMP/SMX included elevated transaminase levels (n = 1), nausea or vomiting (n = 3), thrombocytopenia (n = 2) and neutropenia (n = 2). All episodes of TMP/SMP intolerance occurred following transplantation after a median duration of 17.5 (range 2-48) days and a median of 7 (range 1-20) doses. Resolution of adverse side-effects occurred in all eight patients within a median of 7 (range 2-20) days following discontinuation of therapy. Neither PCP nor bacterial infections were identified in any of the patients treated. This prospective randomized study demonstrated that atovaquone is well-tolerated for anti-Pneumocystis prophylaxis in autologous PBSC transplant patients intolerant of TMP/SMX.

Combined histocompatibility leukocyte antigen-matched donor bone marrow and renal transplantation for multiple myeloma with end stage renal disease: the induction of allograft tolerance through mixed lymphohematopoietic chimerism

BACKGROUND

Experimental and clinical evidence has demonstrated that the establishment of allogeneic chimerism after bone marrow transplantation may provide donor-specific tolerance for solid organ allografts.

METHODS

Based on the preliminary results of a clinical trial using nonmyeloablative preparative therapy for the induction of mixed lymphohematopoietic chimerism, we treated a 55-year-old woman with end stage renal disease secondary to multiple myeloma with a combined histocompatibility leukocyte antigen-matched bone marrow and renal transplant after conditioning with cyclophosphamide, antithymocyte globulin, and thymic irradiation.

RESULTS

The posttransplant course was notable for early normalization of renal function, the absence of acute graft-versus-host disease, and the establishment of mixed lymphohematopoietic chimerism. Cyclosporine, which was the only posttransplant immunosuppressive therapy, was tapered and discontinued on day +73 posttransplant. No rejection episodes occurred, and renal function remains normal on day + 170 posttransplant (14 weeks after discontinuing cyclosporine). Although there is presently no evidence of donor hematopoiesis, there is evidence of an ongoing antitumor response with a recent staging evaluation showing no measurable urine kappa light chains. The patient remains clinically well and is off all immunosuppressive therapy.

CONCLUSION

This is the first report of the deliberate induction of mixed lymphohematopoietic chimerism after a nonmyeloablative preparative regimen to treat a hematological malignancy and to provide allotolerance for a solid organ transplant.

Mixed lymphohaemopoietic chimerism and graft-versus-lymphoma effects after non-myeloablative therapy and HLA-mismatched bone-marrow transplantation

BACKGROUND

HLA-mismatched donor bone-marrow transplantation after standard myeloablative conditioning therapy for haematological malignant disorders has been limited by severe graft-versus-host disease (GVHD) and graft failure. We tested a new approach to find out whether lymphohaemopoietic graft-versus-host reactions could occur without excessive GVHD in mixed haemopoietic chimeras produced across HLA barriers with non-myeloablative conditioning.

METHODS

Five patients with refractory non-Hodgkin lymphoma underwent bone-marrow transplantation from haploidentical related donors sharing at least one HLA A, B, or DR allele on the mismatched haplotype. Conditioning included cyclophosphamide and thymic irradiation before transplantation, and antithymocyte globulin before and after transplantation. The only other GVHD prophylaxis was cyclosporin.

FINDINGS

Four of five patients were evaluable and showed engraftment. Mixed haemopoietic chimerism was established, with a predominance of donor lymphoid tissue and varying degrees of myeloid chimerism. Two patients were in GVHD-free states of complete and partial clinical remission at 460 and 103 days after bone-marrow transplantation.

INTERPRETATION

Mixed chimerism can be induced in adult recipients of HLA-mismatched bone-marrow transplantation by a non-myeloablative conditioning regimen. The antilymphoma responses seen in two patients suggest that allogeneic bone-marrow transplantation without myeloablative conditioning might have potent immunotherapeutic benefits.

Phase I-II trial of high-dose cyclophosphamide, carboplatin and autologous bone marrow or peripheral blood stem cell rescue

In an effort to evaluate the toxicities and anti-tumor efficacy of the combination of high-dose cyclophosphamide (CY) and carboplatin, we undertook a phase I-II trial with autologous bone marrow (BM) or peripheral blood stem cell (PBSC) rescue for patients with solid tumors. Forty three patients, 39 of whom had either high risk stage II or III or metastatic breast cancer were treated with escalating doses of carboplatin 1200-1800 mg/m2 and cyclophosphamide 4800-6000 mg/m2 over 3 days followed by autologous BM or PBSC infusion. No life-threatening or fatal toxicities were observed. Reversible congestive heart failure was seen in two patients. Transient hepatotoxicity, characterized primarily by elevation of transaminase levels, and nausea and vomiting, adequately managed with anti-emetic therapy, were seen in 39 and 40 of 43 patients, respectively. The 14 month post-transplant probability of relapse-free survival for 26 patients with high risk II-III breast cancer was 79%; for 13 patients with metastatic disease, the 22 month relapse-free survival probability was 23%. High-dose carboplatin and CY at maximally administered doses of 1800 mg/m2 and 6000 mg/m2 is a well tolerated preparative transplant regimen for autologous BM or PBSC transplantation. It appears to have similar anti-tumor activity and an improved safety profile when compared with other commonly employed transplant preparative regimens.