1.0. INTRODUCTION AND PROTOCOL RATIONALE 
1.1) Rationale for bone marrow transplant in leukemia: 
Bone marrow transplantation has been used to 
increase the long-term survival for patients with 
acute leukemia and holds the only hope for cure in 
patients who relapse after successful induction 
therapy. For patients undergoing an HLA-matched 
sibling allogeneic bone marrow transplant (AlloBMT) 
the long-term survival is approximately 55% for 
acute myelogenous leukemia (AML) transplanted in 
first remission and approximately 45% for patients 
with acute lymphocytic leukemia (ALL) transplanted 
in second remission (1-12) . 
Unfortunately, only 25-30% of patients with acute 
leukemia have a HLA-matched donor. Also, the 
success of AlloBMT is related to the patient's age 
and most centers exclude patients over 50. 
Considering the peak incidence of AML is in the mid 
to late 50' s, only 10-15% of AML patients are 
currently eligible for AlloBMT (13,14). In 
addition, if there is no HLA-matched sibling 
available to donate the bone marrow, there often is 
a lengthy delay in finding a suitable HLA-matched 
unrelated donor during which time the patient may 
relapse. For these reasons autologous bone marrow 
transplantation (AuBMT) has been evaluated in the 
treatment of acute leukemia. 
AuBMT for acute leukemia is becoming an 
increasingly common procedure. Of the 2700 patients 
registered in the International Autologous Bone 
Marrow Transplant Registry in 1987, 19% received 
AuBMT for AML and 15% for ALL (15) . The number of 
AuBMT performed for acute leukemia is increasing, 
with a four fold increase between 1983 and 1987 
(15.16) . Preliminary data for autologous BMT in 
acute leukemia is encouraging. The 3 year disease- 
free survival is approximately 50% for AML patients 
transplanted in first remission (17-23) . The 
relapse rate is higher for AuBMT than AlloBMT but 
the treatment related mortality for AuBMT is less 
than 10% (14,18,19,24,25) so that the overall 
survival for the two procedures are similar 
(13.17) . It is possible that the apparent success 
of AuBMT in AML is related to patient selection 
bias (26) . Currently randomized prospective 
clinical trials comparing allogenic and autologous 
bone marrow transplant in AML are underway in 
Europe and the US to address this issue. 
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Recombinant DNA Research, Volume 15 
