Allogeneic hematopoietic cell transplantation for neuroblastoma: the CIBMTR experience.

Although the role of autologous hematopoietic cell transplantation (auto-HCT) is well established in neuroblastoma (NBL), the role of allogeneic HCT (allo-HCT) is controversial. The Center for International Blood and Marrow Transplant Research conducted a retrospective review of 143 allo-HCT for NBL reported in 1990-2007. Patients were categorized into two different groups: those who had not (Group 1) and had (Group 2) undergone a prior auto-HCT (n=46 and 97, respectively). One-year and five-year OS were 59% and 29% for Group 1 and 50% and 7% for Group 2, respectively. Among donor types, disease-free survival (DFS) and OS were significantly lower for unrelated transplants at 1 and 3 years but not at 5 years post HCT. Patients in CR or very good partial response (VGPR) at transplant had lower relapse rates and better DFS and OS, compared with those not in CR or VGPR. Our analysis indicates that allo-HCT can cure some neuroblastoma patients, with lower relapse rates and improved survival in patients without a history of prior auto-HCT as compared with those patients who had previously undergone auto-HCT. Although the data do not address why either strategy was chosen for patients, allo-HCT after a prior auto-HCT appears to offer minimal benefit. Disease recurrence remains the most common cause of treatment failure.

Clinical outcomes of patients with desmoplastic small round cell tumor of the peritoneum undergoing autologous HCT: a CIBMTR retrospective analysis.

Desmoplastic small round cell tumor of the peritoneum (DSRCTP) is a rare, frequently fatal tumor. This retrospective study, based on CIBMTR registry data, describes the largest reported cohort of DSRCTP patients who have undergone Auto-SCT. The probabilities of disease-free survival (DFS) at 1 year for patients in CR and not in CR were 75% (95% confidence interval: 48-94%) and 35% (15-59%), respectively. The probability of OS at 3 years was 57% (29-83%) and 28% (9-51%) for patients in CR and not in CR, respectively. Median survival for the entire cohort was 31 months (36 months and 21 months for those in CR and not in CR, respectively). Engraftment at 42 days was 97% (88-100%). Treatment-related mortality was low, with only one death in the first 100 days. Auto-SCT is a tolerable approach in patients with DSRCTP, with the greatest benefit seen in those patients who obtain CR. For those not in CR, the median OS in this series is greater than previously reported (21 months vs 17 months), suggesting Auto-SCT is useful in prolonging DFS and OS, even in patients with residual or persistent disease pre-transplant.

Safety of the live, attenuated varicella vaccine in pediatric recipients of hematopoietic SCTs.

VZV is an important cause of morbidity and mortality among patients after hematopoietic SCT (HSCT). There is controversy surrounding the use of the live attenuated varicella vaccine (LAVV) in this population due to concerns that the immunization may cause VZ-related disease. The Blood and Marrow Transplant (BMT) group at the University of California, San Francisco (UCSF) Children's Hospital has been recommending the LAVV for immunocompetent HSCT patients since 1995. We retrospectively examined the incidence of post-immunization complications attributable to the LAVV in pediatric patients after HSCT. We also reported seroconversion rates when possible. Among 68 recipients of the LAVV after HSCT, 3 (4.4%; 95% confidence interval (CI)=1.0-12.7%) experienced mild-to-moderate symptoms potentially attributable to vaccination, and there were no severe reactions. Among 28 patients analyzed for seroconversion, 18 (64.3%; 95% CI=45.8-79.4%) seroconverted, 3 (10.7%; 95% CI 2.9-28.0%) possibly seroconverted and 7 (25.0%; 95% CI=12.4-43.6%) failed to seroconvert. It appears safe to administer the LAVV to immunocompetent patients after HSCT. Prospective studies are needed to more accurately determine rates of vaccine complications, efficacy and immunologic responses to vaccination.

Increasing mixed chimerism and the risk of graft loss in children undergoing allogeneic hematopoietic stem cell transplantation for non-malignant disorders.

We performed quantitative PCR-based serial chimerism testing of whole blood (WB) and CD3+ cells and retrospectively correlated the results of chimerism tests and the risk of graft loss in children undergoing transplant for non-malignant disorders. Twenty-four children were included in this study. All patients initially engrafted; subsequently, 12% lost the graft, 21% achieved complete donor chimerism and 67% had mixed chimerism (MC). Patients underwent delayed taper of cyclosporine (CsA) if they had MC. Overall survival was 87+/-7% (s.d.) at 5-years post transplant, and it was not affected by chimerism status. Both WB and CD3+ chimerism showed significant fluctuations with a peak in autologous cell signal occurring at a median of 7 months for WB and 2 months for CD3+ cells. Initial post transplant chimerism percentage in either WB or CD3+ lineage was not related to graft loss. Increasing MC to >30% host cells was seen in 33% of patients, and it was related to increased risk of graft loss, as previously published. However, 63% of children with increasing MC did not lose their graft. Additional studies of post transplant chimerism are required to improve our ability to accurately identify children at risk of graft loss following transplant for non-malignant disorders.

Intracranial ependymomas of childhood: current management strategies.

Children with intracranial ependymomas have relatively poor outcomes despite the low-grade histology of these tumors and recent advances in diagnosis, microneurosurgical resection, and adjuvant therapy. Aggressive surgical resection and postoperative adjuvant therapy result in only a 5-year survival rate of 50%. In this paper, we provide a review of the current technical aspects of surgical resection, and focus on recent studies of the epidemiology, molecular markers, prognostic factors and adjuvant therapy for childhood intracranial ependymomas and discuss their implications for current and future management strategies.