1 . 0 OBJECTIVES 
1.1 To evaluate the relative contribution of peripheral blood 
versus marrow in contributing to hematopoietic recovery 
following preparative therapy of CML patients receiving 
autologous transplants. 
1.2 To clarify the origin of Ph+ blast cells which reappear 
after transplant in those second chronic phase patients 
in whom autologous cells had been stored at a time of 
cytogenetic or hematological remission following 
conventional dose chemotherapy used to induce the second 
chronic phase from accelerated phase or blast crisis. 
1.3 To analyze the hematological and cytogenetic response 
following autologous transplant. 
2 . 0 BACKGROUND 
The use of exogenous hematopoietic reconstitution has 
permitted the delivery of intensive therapy for conversion of 
blast crisis to chronic phas^. This therapy is designed to 
generate reinduction of chronic phase and long term disease- 
free cytogenetic remissions following autologous 
transplantation and allogeneic bone marrow transplantation (1- 
3) . In the case of CML patients with early chronic phase 
disease, the use of allogeneic bone marrow transplantation 
results in 50% cures, whereas delivery of intensive therapy 
during later phases of the disease results in a lower 
frequency of long term disease-free survivorship (1). 
The use of autologous cells collected at diagnosis which are 
100% Philadelphia chromosome positive for infusion after 
intensive therapy has resulted in durable cytogenetic 
remissions in a small number of chronic phase patients (10- 
20%) . Durable cytogenetic remissions may be possible in a 
larger number of cases if the autologous cells are collected 
at a time of cytogenetic remission and if interferon 
maintenance therapy is used. Durable cytogenetic remissions 
may also be obtained by this therapy in late chronic phase, 
accelerated phase, or blast crisis patients (4-7) . The 
cytogenetic conversion is presumably due to the fact that 
Philadelphia chromosome positive cells are selectively 
amplified at later stages of myeloid differentiation and the 
ratio of normal progenitors to Philadelphia chromosome 
positive cells among cells which contribute to hematopoietic 
recovery after chemotherapy or transplantation is higher at 
earlier stages of myeloid maturation than it is at later 
stages (8) . 
In a pilot trial at this institution, the durable remissions 
were increased (75%) among chronic phase, accelerated phase, 
or blast crisis patients whose autologous cells were 
predominantly diploid at the time of autologous stem cell 
[860] 
Recombinant DNA Research, Volume 15 
