Researchers from Italy have reported that the injection of umbilical cord blood directly into the pelvic bones of patients with leukemia appears promising. These results were recently published in an early online publication of the Lancet Oncology on August 9, 2008.
Transplantation of bone marrow, peripheral blood stem cells, and umbilical cord blood is accomplished by intravenous infusion. The original studies of human bone marrow transplantation were carried out by direct infusion into bone marrow spaces. However, this approach was abandoned as there was no advantage in speed or rate of engraftment over intravenous infusion. Since these early days of transplantation, there have been sporadic attempts to evaluate intra-osseous infusion of stem cells, but no advantage over intravenous infusion was ever found. The reason for this is thought to be that direct infusion of stem cells into the marrow cavity is in fact identical to intra-arterial or intra-venous infusion, and most stem cells enter the general circulation before homing into marrow spaces throughout the body.
Umbilical cord blood transplantation is associated with relatively high graft failure rates thought to be due to the relatively low dose of stem cells in each collection. Researchers have suggested that the infusion of stem cells from two separate cord blood collections alleviates the graft failure problem. However, Italian researches have posed the question of whether or not intra-osseous infusion would be better.
The current trial evaluated direct infusion of umbilical cord blood into the pelvic bones. This trial included 32 patients with acute myeloid leukemia (AML) and 12 with acute lymphoblastic leukemia (ALL); median age was 36 years. Overall, 14 patients had advanced-stage disease that did not respond to standard therapies, and no patient had a suitable donor for the stem cell transplant.