4. 慢性骨髄性白血病根絶のための強力化学療法について

抄録

In an attempt to determine if intensive treatment might alter the course of chronic myelogenous leukemia by eliminating the Ph¹-positive leukemia cells and induce a state more analogous to the remission which can be attained in acute leukemia, an intensive program of therapy was employed in a few patients with Ph¹-positive CML.
Following the induction of a clinical remission with standard therapy, the first group of the patients underwent splenectomy, the second group Cyto-DCMP therapy and the third group splenectomy followed by Cyto-DCMP therapy with cyclophosphamide (day 1) and subsequently daunomycin (day 4), cytosine arabinoside (days 4 to 10), 6-mercaptopurine (days 4 to 10) and predonine (days 4 to 10). It seemed unlikely that splenectomy increased likelihood of achieving a karyotypic conversion with Cyto-DCMP therapy. One of the splenectomized patients without intensive chemotherapy was noted to have developed a stepwise occurrence of successive cytogenetic changes (double Ph¹-positive) 9 months after splenectomy.
In the patients treated with Cyto-DCMP, however, there were two conversions. One had a transient conversion in his marrow metaphases to predominantly Ph¹-negative cells. The other was converted predominantly double Ph¹-positive marrow to single Ph¹-positive state which is identifiable as a karyotypic standard type of CML. In the remaining two patients, there has been no elimination of Ph¹-positive cells. The present study indicated the ability of Cyto-DCMP therapy to convert the karyotipically abnormal marrow without the aid of splenectomy.
Thus, the finding which was capable of beneficially changing the additional aneuploid features in the chronic phase of CML suggested the possibility to prevent the occurrence of the fatal blast crisis.