Biomedical subjects
Publications and source records attributed to A Turker.
Therapy related acute myeloid leukemia occurs after exposure to various cytotoxic agents. Among typical chemotherapeutic agents are the alkylating agents and topoisomerase II inhibitors. This type of leukemia has been reported after the use of antimetabolites. We report here a patient who developed therapy related acute myeloid leukemia secondary to the use of 5-fluorouracil.
During the immunodiagnosis of 517 cases of acute myelogenous leukemia (AML) entered into the Medical Research Council (MRC) AML 10 trials, we have observed the CD34 precursor cell antigen more frequently in AML of M2 morphology, especially in the 84% of cases with the t(8;21) chromosomal translocation, than in any other French-American-British classification group. CD34 expression was then quantified (using QIFI and Quantum Simply Cellular beads [Flow Cytometry Standards, Research Triangle Park, NC] and CD34+ standard cells). When CD34 antibody-binding capacity (ABC) of normal bone marrow (BM) precursors and leukemic blasts was compared, it was shown that AML M2 cases with t(8;21) not only had the highest percentages of CD34+ blasts, but in > 80% of CD34+ cases the individual blasts expressed higher than normal levels of CD34 antigen (> 60 x 10(3) ABC per cell). In addition, in 73% of this group CD34 antigen was overexpressed in an asynchronous combination with cytoplasmic myeloperoxidase (MPO). Other signs of asynchrony included high CD34 expression with CD15 and/or CD56, as well as aberrant combinations of CD13 with terminal deoxynucleotidyl transferase (TdT) and CD19. These findings demonstrate that asynchrony is identifiable in virtually every case of AML with t(8;21), although it does not always involve the same antigens. M2 cases with t(8;21), mostly CD34+, had a 100% remission rate and 71% 5-year survival rate; other patients with CD34+ or CD34- AML showed 69% and 84% remission rates and 31% and 36% 5-year survival rates, respectively. Consequently, individual markers such as CD34 should be interpreted in relation to other features such as chromosomal changes. These simple methods, which are well suited to quantify the expression of ligands, are a useful contribution to diagnosis: 60% to 65% of M2 cases with t(8;21) are rapidly identified by CD34 overexpression alone. This aberration, together with the other signs of asynchrony seen at presentation, can be used to search for residual leukemia after therapy.
Ninety-eight adult patients with acute myeloid leukemia were given variable remission induction/consolidation regimens containing idarubicin. Sixty-nine (70%) were new cases (median age, 56 years) and 29 (30%) were in relapse (n = 24) or had primary refractory disease (n = 5) (median age, 46 years). Complete remission (CR) rates were 57% (39 of 69 patients) of the newly diagnosed patients, with no difference for those below or above 55 years of age (56% v 59%) or for patients exhibiting white blood cell counts of less or more than 50 x 10(9)/L (52% v 69%; P = .8). Of the 39 patients who achieved CR, 26 (67%, 38% of the total number of patients) remain in CR with a median follow-up of 3 months (range, 0 to 61 months). Forty-two percent of the relapsed cases (10 of 24 patients) and 60% of the primary refractory disease cases (three of five patients) achieved CR. Of these 13 responders, six are alive (three continuing in CR and three relapsed) with a median follow-up of 3 months (range, 1 to 20 months), and seven have died with a median survival of 7 months (range, 0 to 12 months). Of the 52 patients who have achieved CR, 84% did so with one course of treatment and 16% with two courses. The presence of normal cytogenetic analysis or favorable chromosomal aberrations significantly improved overall CR rates. The patients in this study had significantly more unfavorable cytogenetic abnormalities than the historic controls. Reported toxicity was hepatic in 13%, cardiac in 9%, and renal in 7% of all cases. These data suggest a comparable efficacy of idarubicin to other anthracyclines in remission induction of acute myeloid leukemia, with a promising role in relapsed/refractory disease.