MYELOID MARKERS IN ADULT ACUTE LYMPHOCYTIC-LEUKEMIA - CORRELATIONS WITH PATIENT AND DISEASE CHARACTERISTICS AND WITH PROGNOSIS

Background. The expression of myeloid markers on lymphoblasts has been associated with adverse outcome in acute lymphocytic leukemia (ALL). The purpose of the study was to analyze the experience with adults tre ated at the University of Texas M.D. Anderson Cancer Center with myelo id marker- (MY) positive ALL in relation to patient and disease charac teristics, response to therapy, and prognosis. Methods. Since 1988, 64 of 162 adults (40%) with newly diagnosed ALL referred to our service had MY-positive ALL. Their characteristics and outcomes were compared with the 98 patients with MY-negative ALL. Patients were treated with the vincristine-doxorubicindexamethasone (VAD) regimens. Results. Pati ents with MY-positive ALL were significantly older (median ages, 47 ye ars vs. 33 years; P = 0.03), had a higher incidence of CD34 antigen ex pression (59% vs. 36%; P < 0.01), and a lower incidence of common acut e leukemia antigen expression (50% vs. 71%; P < 0.01), serum alkaline phosphatase elevation (58% vs. 83%; P < 0.01), and thrombocytopenia at diagnosis (49% vs. 69%; P = 0.02). Myeloid marker positivity, as expe cted, was significantly higher in null cell ALL (82%), and significant ly lower in mature B-cell ALL (17%) (P < 0.01). Forty-one of 64 MY-pos itive patients achieved complete remission (CR) after induction therap y compared with 76 of 98 patients MY-negative disease (CR rate 64% vs. 78%; P = 0.06). With a median follow-up of 45 months, no statistical differences were observed in remission duration or survival between MY -positive and MY-negative patients, overall, and within imunophenotypi c subsets (T-cell vs, others), or among subgroups with single marker ( CD13, CD14, CD33, CD34) positivity. The 3-year remission duration rate s were 32% for MY-negative and 40% for MY-positive patients (P not sig nificant), and 3-year survival rates were 26% and 31%, respectively (P not significant). Conclusions. With VAD therapy, myeloid marker posit ivity is not associated with significant differences in prognosis in a dult ALL.