Current status of pediatric umbilical cord blood transplantation in Korea: A multicenter retrospective analysis of 236 cases

Abstract

We report the outcome of 236 pediatric umbilical cord blood transplantations (UCBT) performed in Korea. Given that the sources of the grafts were mostly unrelated donors (n 5 226; 95.8%), only the results of unrelated UCBT were included for all statistics. The most frequent primary disease was acute leukemia (n 5 167). In total, 91.7% of recipients were seropositive for cytomegalovirus (CMV). The median doses of nucleated cells and CD341 cells were 4.84 3 10 7 /kg and 2.00 3 10 5 /kg, respectively. The median times to neutrophil (>0.5 3 10 9 /L) and platelet recovery (>20 3 10 9 /L) were 18 and 45 days, respectively. Grade 2-4 acute graft-versushost-disease (GVHD) and chronic GVHD developed in 41.1 and 36.1% of cases, respectively. Forty-five patients developed CMV disease. The 5-year overall and event-free survival were 47.5 and 36.9%, respectively. Multivariate analysis revealed that adverse factors for survival of the whole cohort were total body irradiation-based conditioning (P 5 0.007), salvage transplant (P 5 0.001), failure to achieve early complete chimerism (P < 0.0005), and CMV disease (P 5 0.001). The outcomes of the single-and double-unit UCBT (n 5 64) were similar, while double-unit recipients were heavier (P < 0.0005) and older (P < 0.0005). We conclude that double-unit UCBT is a reasonable option for older or heavier children and that the thorough surveillance of CMV infection and the development of an effective CMV therapeutic strategy may be especially important for Korean children, whose CMV seroprevalence exceeds 90%. Am. J. Hematol. 86:12-17, 2011. V

Epstein-Barr virus and cytomegalovirus infections and their clinical relevance in Egyptian leukemic pediatric patients

“…These findings suggest that severe CMV infection and possibly EBV infection might play a role in the progression of leukemia and might be a useful indicator of worsening the clinical course of the disease. Similar findings were reported by Yoo and his colleagues on Korean pediatric umbilical cord blood transplant patients where the presence of CMV disease was among factors that adversely affected the survival rates of all patients [34]. …”

Hematopoietic stem cell transplantation in children with acute leukemia: similar outcomes in recipients of umbilical cord blood versus marrow or peripheral blood stem cells from related or unrelated donors

“…A multicenter analysis of 236 children who underwent UCBT in Korea suggested that UCBT was a reasonable alternative as an HSC source9).…”

Intensive strategy to prevent CMV disease in seropositive umbilical cord blood transplant recipients

“…11,12 Because high viral loads have been shown to be strong predictors for the development of CMV disease, 13,14 UCBT recipients may also be at increased risk for the development of viral invasion. Incidence rates of CMV in UCBT vary, with reported rates of reactivation fluctuating from 21% to 100% [15][16][17] and CMV disease between 6% and 21%, [17][18][19][20] but different prevention methods and the inclusion of low-risk seronegative recipients limit comparisons.…”