Allogeneic transplantation is the only curative option for patients with high risk hematologic malignancies. Only one third of them have an HLA identical sibling donor and around 60-70% will find an unrelated donor, that´s why HAPLO-HSCT offers a therapeutic option to most of these patients with the advantages of quick availability, easy programation and logistics, and a committed donor.
We retrospectively evaluate the results of HAPLO-HSCT with reduced conditioning or myeloablative regimens and GVHD prophylaxis based on HD-CY (50 mg/kg on days +3 and +4) and a calcineurin inhibitor plus mycophenolate from day +5 performed in GETH centers.
From Dec-2007, 80 HAPLO-HSCT have been done in 14 centers. Median age was 37 years (16-66), 67.5% were males and all were in advanced phases of their disease or presented high risk features (29 Hodgkin´s, 22 AML, 9 ALL, 8 MDS, 5 NHL, 4 myeloma and 2 myelofibrosis). Previous HSCT has been employed in 65%, autologous in 38 and allogeneic in 15 (5 siblings, 3 unrelated and 7 cord blood transplants), and in 35% the HAPLO-HSCT was their first transplant. Disease status at HAPLO-HSCT was CR in 45%, with persistent disease in 55%. Bone marrow was the graft source for 51% and peripheral blood for 49%, non T-cell depleted in all cases. The haploidentical donor was the patient´s mother (21), father (7), brother/sister (35) or offspring (17). Non-myeloablative conditioning was employed in 77.5% and myeloblative in 22.5%. Median neutrophils engraftment was reached at day +18 (13-45) and platelets >50K at day +27 (11-150). Main toxic complications were grade II-III muchositis in 36%, febrile neutropenia in 75% and CMV reactivations in 62%, with a transplant related mortality rate of 12.5% at day +100 and 19% at 6 months post-transplant. Acute GVHD grade II-IV affected to 24/73 patients at risk (33%), with grade III-IV in 10/73 (14%). Chronic GVHD was present in 12/51 (24%), being extensive in 6/51 (12%). After a median follow-up of 9 months (0.3-49), 26/80 patiens have died due to relapse in 13, infections in 10 and GVHD in 3 cases. Event-free survival and overall survival at 1 year were 48% and 60% respectively. Immune reconstitution was fast and complete in those evaluated.
HAPLO-HSCT with HD-CY is a useful tool in the treatment of high risk hematologic malignancies, rendering long-lasting remissions with limited toxicity, low GVHD incidence and early immune reconstitution.
No relevant conflicts of interest to declare.
Asterisk with author names denotes non-ASH members.