PARTIALLY MISMATCHED BLOOD-CELL TRANSPLANTS FOR HIGH-RISK HEMATOLOGICMALIGNANCY

Eleven patients with high-risk hematologic malignancy received cryopre served but otherwise unmanipulated blood cell transplants (BCT) from p artially mismatched family members in whom progenitor cells had been m obilized by G-CSF. Donors were mismatched by up to one antigen in the GVH direction and up to three antigens in the rejection direction. Out comes were compared with those of 22 patients receiving BCT from fully matched donors. Two mismatched patients died without engraftment on d ay 21 and 32. One had rejected bone marrow from the same donor, the ot her was mismatched by two antigens in the rejection direction and rece ived the lowest dose of CD34(+) cells. Median time to granulocyte engr aftment was 21.5 (range 16-33) days for the mismatched group compared with 16 (11-28) days for the matched group (P = 0.01). No correlation was found between CD34(+) cell dose and time to granulocyte or platele t recovery. In the mismatched and matched BCT groups respectively, the risk of grade II-IV acute graft-versus-host disease (GVHD) was 73% vs 28% (P = 0.001) and of chronic GVHD 100% vs 78% at 18 months (P = 0.0 1). The relationship of T cell dose to acute GVHD could only be evalua ted in the matched group and no correlation was found. One of 11 misma tched patients and eight of 22 matched patients had relapse or persist ent disease. Disease-free survival at 1 year was similar at 55% for mi smatched and 50% for matched BCT. These results indicate that allogene ic BCT from partially mismatched family members is accompanied by a hi gh incidence of GVHD but may result in comparable survival to BCT from fully matched donors.