transplantation of autologous marrow placed in liquid 
culture for ten days. 39 Patients were considered eligible 
for therapy if marrow samples in long term culture showed 
suppression of Ph+ cells and enhanced growth of normal 
progenitor cells. 100% Ph- cells were seen in 8 patients 
immediately post-transplant. Seven patients continued in 
hematologic remission with 84-100% Ph- cells at 5-33 months 
follow up. 
Ex-vivo purging with interferons or 4- 
hydroperoxycyclophosphamide (4-HC) has resulted in complete 
hematologic remission as well as disappearance of the 
Philadelphia chromosome in occasional patients. 40 ' 41 
Unfortunately, the clinical benefit of purging for CML cells 
or cells from other malignant marrow infiltrative diseases 
has not yet been proven convincingly in humans. 
Alternatively, prolonged remissions in CML may be 
achieved without marrow purging. Goldman and co-workers 
recently reported that some patients transplanted in chronic 
phase recover post-transplant with Ph- cells which may be 
associated with prolonged survival. 4 Sixteen patients with 
chronic phase disease received intensive therapy and 
autologous transplant with unmanipulated peripheral blood 
progenitor cells. In two. patients hemopoiesis was almost 
exclusively Ph- at 48 and 63 months post-autograft. 
Actuarial survival at 5 years was 63% with many patients no 
longer requiring therapy. These promising results require 
confirmation, but form the basis for our approach to 
inducing Ph- cell populations in patients with CML. 
Conditioning Regimens for Marrow Transplantation : 
A variety of conditioning regimens have been employed 
in an attempt to decrease leukemia or lymphomatous relapse 
post-transplant. Unfortunately, no marrow transplant 
conditioning regimens have shown overall survival advantages 
over standard cyclophosphamide (6 0mg/kg I.V. x 2) and total 
body irradiation (TBI) [200 cGy x 61 (Cy/TBI) when compared 
in prospective, controlled studies. 2 Although occasionally 
the risk of relapse decreases with more intensive 
conditioning regimens, toxicity often is increased and 
negates any survival advantage. 43 The toxicity of Cy/TBI is 
well established. Recent studies using Cy/TBI for patients 
with recurrent non-Hodgkin's lymphoma have shown a regimen- 
related mortality rate of less than 5% which is most likely 
related to improvement in supportive care. 44 
Interferon Post-Autologous Bone Marrow Transplantation ; 
Since many patients will recur with Ph+ cells 
post-autografting, the addition of interferon following 
transplantation has been evaluated in a small study. In 
several patients previously resistant to interferon, post- 
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Recombinant DNA Research, Volume 16 
