Cord blood transplantation for adult patients with hematological malignancies

Recently, clinical studies of cord blood transplantation (CBT) in adults after myeloablative or nonmyeloablative conditioning regimens showed cord blood (CB) could effectively restore hematopoiesis and was associated with acceptable levels of graft versus host disease (GVHD).

This study reports the results of cord blood transplantation in 7 adults with hematological malignancies.

Median age was 56 years (range, 43-69 years). HLA match was 4 of 6 in 4 cases and 5 of 6 in 3 cases. Median nucleated cell dose was 2.74 x 10(7) cells/kg (range, 2.13-3.80) and CD34+ cell dose was 1.15 x 10(5) cells/kg (range, 0.44-2.79). Three patients had primary graft failure. There was one early death at day 24 after CBT due to pneumonia. Three patients with engraftment are alive and free of disease at day 390, day 348 and day 164 after CBT. Acute GVHD grade II occurred in 2 cases with engraftment, and chronic GVHD occurred in 1 of 3 evaluable patients. Six patients with and without engraftment received more than 2.0 x 10(7) cells/kg nucleated cells. Three patients without engraftment received CD34+ cell dose less than that of 3 patients with engraftment.

It is considered that graft CD34+ cell dose besides nucleated cell dose is important for engraftment. We believe that adult patients without suitable related or unrelated bone marrow donors should be considered as candidates for CBT by the choice of CB including both sufficient nucleated cell dose and CD34+ cell dose.