2ND ALLOGENEIC TRANSPLANTS FOR LEUKEMIA USING BLOOD INSTEAD OF BONE-MARROW AS A SOURCE OF HEMATOPOIETIC-CELLS

There is increasing interest in blood cell transplants (BCT) from norm al donors as an alternative to BMT. Ten patients with relapsed or pers istent leukemia after BMT received intensive cytotoxic conditioning fo llowed by allogeneic BCT, Three BCT were from single-antigen mismatche d donors; two of the corresponding recipients had rejected a BMT from the same donor. Two patients received BCT from a different donor (one matched, one single-antigen mismatched), The other six BCT were from t he same, fully matched, bone marrow donors. Donors were given G-CSF to mobilize progenitor cells which were collected by a single 2-4 h leuk apheresis. Methotrexate, CsA and folinic acid were used for GVHD proph ylaxis for all transplants but CsA was discontinued sooner after BCT t han after BMT. One patient died without engraftment having rejected a BMT from the same single-antigen mismatched donor 4 years previously, Nine patients had granulocyte recovery at a median of 14 days, up to 6 days faster than with their previous BMT, Platelet recovery was also 2-6 days faster than,vith BMT in four previously engrafting patients, Four patients died without platelet recovery after BCT within a year o f BMT, three of treatment-related toxicity and one of relapse. Two pat ients developed grade II acute GVHD. Of six patients given BCT more th an a year from BMT, four, all with acute leukemia, survive 7, 14, 29 a nd 29 months after BCT and one relapsed at 7 months, All four survivor s developed chronic GVHD, These results indicate that BCT may be usefu l therapy for relapse occurring more than a year after BMT.