Unrelated umbilical cord blood stem cell transplant after failure of haploidentical or matched unrelated donor hematopoietic stem cell transplant

Umbilical Cord Blood Transplantation after Graft Failure from a Previous Hematopoietic Stem Cell Transplantation

Graft failure (GF) is a life-threatening complication after allogeneic hematopoietic stem cell transplantation (HCT). In the absence of autologous recovery, a second HCT is necessary to attempt to prevent death due to prolonged pancytopenia. Previous studies describing outcomes of second HCT performed after GF with different types of donor sources report widely ranging overall survival (OS) and transplantation-related mortality (TRM); however, studies including a large number of patients undergoing a second HCT with umbilical cord blood (UCB) as the graft source are scarce. This study examined UCB transplantation (UCBT) performed after GF following a previous HCT. This retrospective registry-based study used data extracted from Eurocord and the European Society for Blood and Marrow Transplantation (EBMT) databases to evaluate outcomes of 247 UCBTs performed in EBMT transplant centers after GF following a previous HCT. Data were analyzed separately for patients with malignant diseases (n = 141) and those with nonmalignant diseases (n = 106). The most frequent HCT that resulted in GF was also UCBT (65.0% for patients with malignant diseases and 68.9% for those with nonmalignant diseases), and most GFs occurred within 100 days after transplantation (92.3% and 85.9%, respectively). The median follow-up was 47 months for surviving patients with malignant diseases and 38 months for those with nonmalignant diseases. We observed a similar cumulative incidence of neutrophil engraftment of 59.1% (95% confidence interval [CI], 51.4% to 67.9%) and 60.4% (95% CI, 51.7%-70.6%), respectively, at a median time of 23 days and 24 days, respectively. The 3-year OS was 28.9% (95% CI, 21.8% to 37.3%) in the malignant disease group and 49.1% (95% CI, 39.5%-58.8%) in the nonmalignant disease group. In patients with malignancies, TRM was 39.9% (95% CI, 32.5% to 49.1%) at 100 days and 57.5% (95% CI, 49.4%-66.8%) at 3 years. In multivariate analyses, none of the characteristics studied was statistically significantly associated with engraftment or OS. Although survival is not optimal in patients requiring a second HCT, UCBT remains a valid life-saving option for patients with GF.

Progressive multifocal leukoencephalopathy after allogeneic stem cell transplantation: Case report and review of the literature

Progressive multifocal leukoencephalopathy (PML) is a rare, yet typically fatal complication of allogeneic stem cell transplantation. It is caused by reactivation of the John Cunningham (JC) virus in an immunocompromised host. This report describes an unfortunate case of PML in a recipient of an allogeneic stem cell transplant for acute myelogenous leukemia. The JC virus was undetectable in the patient's cerebrospinal fluid by polymerase chain reaction (PCR); however, a positive diagnosis was made after a brain biopsy. This and other published cases demonstrate that recipients of allogeneic stem cells can develop PML. Moreover, early diagnosis of the disease is often difficult and, as demonstrated in this case, screening with PCR does not appear to have strong diagnostic significance. With no effective treatment presently available, restoration of immune function is the only intervention that can affect prognosis. Further prospective studies are needed to understand the pathophysiology and treatment of this disease.

JC Virus Leuko-Encephalopathy in Reduced Intensity Conditioning Cord Blood Transplant Recipient with a Review of the Literature

We report here the case of progressive multifocal leukoencephalopathy (PML) related to human polyomavirus JC (JCV) infection after an allogeneic transplantation with umbilical cord blood cells in 59-year-old woman with follicular Non Hodgkin lymphoma. She presented with dysphagia and weakness; magnetic resonance imaging demonstrated marked signal abnormality in the sub-cortical white matter of the left frontal lobe and in the posterior limb of the right internal capsule. Polymerase chain reaction (PCR) analysis of the cerebrospinal fluid (CSF) was positive for John Cunningham (JC) virus. JC viral DNA in the CSF was positive, establishing the diagnosis of PML. Brain biopsy was not done. Extensive investigations for other viral infections seen in immuno-compromised patients were negative. The patient's neurologic deficits rapidly increased throughout her hospital stay, and she died one month after the diagnosis. These findings could have practical implications and demonstrate that in patients presenting neurological symptoms and radiological signs after UCBT, the JCV encephalitis must be early suspected.

Feasibility of reduced-intensity cord blood transplantation as salvage therapy for graft failure: results of a nationwide survey of adult patients

To evaluate whether rescue with cord blood transplantation (CBT) could improve the poor survival after graft failure (GF), we surveyed the data of 80 adult patients (median age, 51 years) who received CBT within 3 months of GF (primary 64, secondary 16), with fludarabine-based reduced-intensity regimens with or without melphalan, busulfan, cyclophosphamide, and/or 2-4 Gy total-body irradiation (TBI). A median number of 2.4 × 10(7)/kg total nucleated cells (TNC) were infused, and among the 61 evaluable patients who survived for more than 28 days, 45 (74%) engrafted. The median follow-up of surviving patients was 325 days, and the 1-year overall survival rate was 33% despite poor performance status (2-4, 60%), carryover organ toxicities (grade 3/4, 14%), and infections (82%) prior to CBT. Day 100 transplantation-related mortality was 45%, with 60% related to infectious complications. Multivariate analysis showed that the infusion of TNC ≥2.5 × 10(7)/kg and an alkylating agent-containing regimen were associated with a higher probability of engraftment, and that high risk-status at the preceding transplantation and grade 3/4 organ toxicities before CBT were associated with an increased risk of mortality. In conclusion, in an older population of patients, our data support the feasibility of CBT with a reduced-intensity conditioning regimen for GF.

Infections in 100 cord blood transplantations: spectrum of early and late posttransplant infections in adult and pediatric patients 1996-2005

Cord blood-derived stem cells are successfully used in the treatment of cancer and congenital disorders in children. This alternative source of stem cells is also explored for adult cancer patients with limited donor options. However, delayed engraftment, prolonged neutropenia, secondary graft loss, and graft-versus-host disease (GVHD) in recipients of cord blood transplantation (CBT) make opportunistic infections a serious concern. We evaluated the spectrum of infections in adults and children undergoing CBT at our National Cancer Institute-designated comprehensive cancer center. The infection incidence rate ratio (total infection episodes/days at risk [survival after CBT] x 100) was 2.4 times higher in 35 adult patients than in 62 children, especially in adults with neutropenia (3 x higher) and GVHD (1.9 x higher). Ninety-two percent of fungal infection episodes occurred within 100 days after transplantation; half of these infections occurred in the first 30 days after CBT. Most bacterial infections (80%) were also diagnosed in the first 100 days, whereas late (>100 d) post-CBT cytomegalovirus and varicella zoster virus infections occurred only in children with chronic GVHD. Multivariate analysis showed that resolution of lymphocytopenia (> or =1000 cells/microL) (hazard ratio [HR] 0.71; p < 0.0001) and successful engraftment (HR 0.20; p < 0.0001) were associated with a low risk of serious infection. Children (HR 0.36; p < 0.0002) with sustained engraftment (HR 0.39; p < 0.004) and those with cancer in remission (HR 0.47; p < 0.007) were less likely to die from infection. More effective measures for surveillance and prevention of late cytomegalovirus and varicella zoster virus infections in children with CBT and chronic GVHD are needed.

Human umbilical cord blood-derived stromal cell, a new resource of feeder layer to expand human umbilical cord blood CD34+ cells in vitro

Allogeneic transplantation with human umbilical cord blood (hUCB) in adult recipients is mainly limited by a low CD34+ cell dose. To break the limit, hUCB as a novel source of hUCB-derived stromal cells was incorporated in an attempt to expand CD34+ cells from hUCB in vitro. Cord blood CD34 cells were separated by MACS system. HUCB-derived stromal cells were cultured by the Dexter system and characterized by morphologic, immunophenotypical, and functional analysis. We studied the effects of hUCB-derived stromal cells, cytokines, and hUCB-derived stromal cells combined with cytokines on expansion of hUCB CD34 cells. The CD34+ cells were assessed for the degree of expansion and the number of colony-forming units in semisolid culture. Our research found that hUCB-derived stromal cells were mainly composed of three kinds of cell components, with CD106, CD29, CD44, CD45, CD50, CD68, CD31, Fn, Lm, and collagen IV positive, but CD34 negative immunophenotype. Functionally, it was discovered by cell cycle and growth curve analyses that the capability of colony and parietal layer formation of hUCB-derived stromal cells was poorer than that of BM stromal cells, and the doubling time of hUCB-derived stromal cells was longer than that of BM stromal cells. It was indicated by ELISA and RT-PCR that hUCB-derived stromal cells express higher level of TPO and less GM-CSF and SCF than BM stromal cell. Adherent layer of hUCB-derived stromal cells alone or combining with cytokines, increased CD34+ cell expansion. In vitro formation of CFUs by expanded CCD34 cells was significantly higher than that of unexpanded CD34+ cells (P < 0.05). When cocultured with hUCB-derived stromal cells in the presence of cytokines, cell growth was significantly enhanced: CD34 cells by 8.02 +/- 0.96-fold, CFU-GM by 217.60 +/- 6.72-fold, CFU-E by 1940.80 +/- 52.78-fold, and CFU-Mg by 142.60 +/- 4.39-fold. HUCB-derived stromal cells have significant superiority on the expansion of CFU-Mg (P < 0.05). The results indicate that human umbilical cord blood-derived stromal cells may be a suitable feeder layer for expansion of hematopoietic progenitors from hUCB in vitro.