Researchers report that depleting bone marrow of contaminating malignant cells with anticancer drugs prior to transplantation (purging) may increase long-term survival in certain leukemia patients. This was the conclusion of a comparative study of purged vs nonpurged marrow in patients with acute myelogenous leukemia (AML). The findings were presented at the annual meeting of the American Society of Clinical Oncology (ASCO).
The researchers studied 295 AML patients who underwent autologous bone marrow transplantation (BMT) at the Johns Hopkins Oncology Center and the Medical College of Wisconsin between 1989 and 1993. A total of 212 patients received bone marrow chemically treated with 4-hydroperoxycyclophosphamide (4-HC) to purge the marrow of residual leukemia cells. The remaining 83 patients received untreated marrow.
The rate of leukemia recurrence 1 year or more after transplantation was significantly lower in patients who received purged marrow than in those who received untreated marrow. In addition, purging did not increase deaths related to the transplant. The 5-year probabilities of leukemia-free survival were 48% for purged and 29% for unpurged transplants after a first remission, and 39% for purged and 24% for unpurged transplants after a second remission, according to the study.
Adapted from Newsline, Summer 1996.