BCG-cell wall skeleton completely cures the immunologically eligible acute leukemia patients

Abstract

Eight acute leukemia patients were treated with BCG-cell wall skeleton (CWS) alone after the first complete remission (CR) induction with chemotherapy alone or chemotherapy followed by autologous peripheral blood stem cell transplantation (PBSCT). Two patients, who achieved CR after one course of chemotherapy, were treated with BCG-CWS alone for about 8 years, one starting just after the first relapse and the other just after the first remission. They have been in CR state for more than two decades, without further relapse or other secondary cancers. Recently, their complete cure was confirmed; Wilms tumor (WT)-1 gene expression in their peripheral blood was less than 10-5. Among other 6 patients, who had repeated or intensive chemotherapy, 4 patients responded to immunotherapy with BCG-CWS alone are alive in CR for more than 1 year, but two died shortly thereafter. The most important factor influencing the above patients' fate might be their own immunity at the start of immunotherapy; this can be monitored with the interferon (IFN)-γ induction test. In view of above results, immunotherapy with BCG-CWS alone for acute leukemia patients should be used just after the first CR and before transplantation, because of its priority in such terms as simple procedure, high cost-performance, high quality of life, easy availability and no risk of tuberculosis.