Leukemic relapse following
bone marrow transplantation (BMT) for acute
leukemia is the most common cause of treatment failure. Because a more intensive pre-transplant preparative regimen may prevent disease recurrence we have designed a novel intensive conditioning regimen for BMT using high-energy total body irradiation (total dose 850 cGy; energy 24 MV; midplane received dose rate 26 cGy/min; day -6) followed by
cyclophosphamide (dose 50 mg/kg/day; schedule 2-h infusion; days -5, -4, -3) and continuous infusion high-dose
etoposide (dose 500 mg/m2/day; schedule: 22-h infusion; days -5, -4, -3). Between February 1987 and December 1988, 45 patients with advanced acute
leukemia received transplants using this regimen. Twenty-five purged auto-transplants were done for B-lineage (n = 18), T-lineage (n = 6) or biphenotypic (n = 1)
acute lymphoblastic leukemia, with 12 in remission and 13 in relapse at the time of
transplantation. Of these, nine had non-relapse deaths and 16 have relapsed between 1 and 19 months (median 3 months) following
transplantation. Of note all the T-lineage patients relapsed including two transplanted in remission and five transplanted in relapse. Nineteen patients received histocompatible allogeneic transplants and one underwent
syngeneic transplantation. Of seven patients with
acute lymphoblastic leukemia transplanted in refractory relapse, three have had an overt relapse, three died of
interstitial pneumonitis and only one survives disease free 15 months after
transplantation. Of 13 patients with acute non-
lymphocytic leukemia and variants (11 who were transplanted in relapse) three died without relapse, three have relapsed and seven survive disease free from 9 to 27 months (median 20 months) after
transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)