[Primary graft failure in a patient with refractory acute myeloid leukemia successfully treated with modified 'one-day'-based preparative regimen followed by cord blood transplantation].

A 32-year-old woman with acute myeloid leukemia failed to achieve remission with two courses of induction chemotherapy, and she received cord blood transplantation (CBT) in a non-remission state, using an HLA-matched cord blood (CB) graft after a conditioning regimen of fludarabine (Flu) at 125 mg/m² + melphalan at 140 mg/m² + total body irradiation (TBI) at 4 Gy. Chimerism analysis of the bone marrow (BM) cells performed on day 21 after CBT revealed 99% of these cells to be the recipient type. We diagnosed the patient as having graft failure (GF), and then carried out a second CBT using an HLA-matched male CB graft on day 29 after the first CBT. The conditioning regimen (modified 'one-day'-based regimen) consisted of Flu at 30 mg/m² (3 days) + cyclophosphamide (CY) at 2 g/m² (1 day) + TBI 2 Gy. She achieved neutrophil engraftment on day 18. FISH analysis of BM cells on day 13 showed 96% to be of male origin. She has remained in complete remission for 18 months, to date, since the salvage CBT. This case suggests that salvage CBT following a modified 'one-day'-based regimen may preserve a strong graft versus leukemia effect.