Bone marrow transplantation in acute or chronic leukaemia.

Using T-depleted BM from HLA-identical sibling donors we have performed 36 BMTs since 5/83 in first remission (CR1) of acute leukaemia (AL). Standard conditioning for BMT consisted of Cy 60 mg/kg X 2 and 7.5 Gy single fraction TBI (n = 27). Six patients received Ara-C 3 g/m2 X 6, Cy 45 mg/kg X 2 and 7.5 Gy, while 3 received Cy 60 mg/kg X 2 and 8 Gy radiation. T lymphocytes were depleted in vitro with 2 murine McAbs (MBG6 + RFT8, n = 17; or RFT8 + RFT12, n = 13; or RFT2, RFT8 + RFT12, n = 6) plus rabbit C'-mediated lysis. No immunosuppressive therapy was given in the absence of graft-versus-host disease (GvHD). Of 34 patients evaluable for a GvHD, 4 had grade I, 2 grade II and 1 grade III. Chronic GvHD occurred in 3 of 22 evaluable patients (greater than 150 days). There have been 13 deaths but only 1 from leukaemic relapse (CNS). The mean KS of surviving patients is 86% and actuarial disease-free survival is 53% at 40 months or 65% in those having 'standard conditioning'. The previous major problems of GvHD and leukaemic relapse appear to have been largely overcome. The major risk factor now is infection, particularly pneumonitis, and this problem is surmountable.