Abstract
Abstract 2291
Poster Board II-268
Haploidentical bone marrow transplantation (BMT) is an alternative treatment to patients with high-risk hematologic malignancy lacking a HLA-matched donor and those urgently need transplantation. We used a haploidentical-BMT protocol without ex vivo T cell depleted based on the knowledge that marrow grafts have 10 times fewer lymphocytes compared to peripheral blood stem cell grafts and granulocyte colony-stimulating factor (G-CSF) donor priming reduce the incidence of acute GvHD.
40 patients (median age of 32, 12-63) with advanced disease or leukemia with poor prognostic features underwent unmanipulated haplo-BMT: 22 with AML, 9 with ALL, 3 with CML, 3 with Hodgkin lymphoma and 3 with plasmacell leukemia. Status at disease: 22 early (first or second comple! te remission), 18 advanced (progressive or refractory disease). All pairs of donors and recipients were identical for one HLA haplotype and incompatible at 2 or 3 loci.The myeloablative conditioning regimens used were different; antithymocyte globuline, cyclosporine, metotrexate, mycophenolate mofetil and basiliximab were used for GvHD prophylaxis. Donors were primed with filgrastim at 4 micrograms/Kg/d for 7 consecutive days. Bone marrow cells were harvest on the 8 day and were infused unmanipulated.
the median dose of total nucleated, CD34+ and CD3+cells was 7×10e8/Kg (1.01-28.7), 2.3×10e6/Kg (1.17-6.0) and 23.3×10e6/Kg (9.7-66.6) respectively. 1 patients had a primary graft failure and 5 patients died early prior to engraftment. In the remaining 34 patients, engraftment was seen with median time to granulocyte and platelet recovery of 22 and 27 days respectively; acute GvHD was grade 0 in 17 patients (50%), grade I in 9 (26%), grade II in 7 (20%) and grade IV in 1 (3%). In 29 evaluable patients, chronic GvHD was limited in 3 (10%) and extensive in 1 (3%). Transplant-related mortality at 6 months for early and advantage stage was 22% and 35% respectively. After a median follow up of 18 (3-42) months, 8 patients relapsed; 11 patients (50%) in the early stage and 4 (22%) in advanced phase are now living in haematological remission. The 1-year Kaplan-Meyer probability of disease-free survival is 45% for all patients.
the high engraftment rate, low incidence of grade II-IV acute GvHD and an acceptable TRM suggest that G-CSF-primed marrow grafting along with sequential immunosuppression could provide an excellent alternative for patients who lack matched donors.
No relevant conflicts of interest to declare.
Author notes
Asterisk with author names denotes non-ASH members.
