Prognostic significance of the acute lymphoblastic leukemia (All) cell-associated antigen in children with null-cell all

The leukemic cells of 50 children with null-cell acute lymphoblastic leukemia (null-ALL) were studied at the time of diagnosis for the presence or absence of an ALL cell-associated antigen (ALLA). Eleven of the patients were ALLA(−) and the remainder were ALLA(+). The clinical courses of these patients were followed prospectively for 2–34 months. In the ALLA(−) group, 7 of 11 patients suffered a disease-related adverse event [induction failure; bone marrow (BM), central nervous system (CNS) or testicular relapse; death] by 13 months from diagnosis. In the ALLA(+) group, there were seven disease-related adverse events in 39 patients within 29 months after diagnosis. The difference in the incidence of disease-related adverse events between the two groups is statistically significant, i.e., 7/11 versus 7/39 (p = 0.005 by Fisher’s Exact Test). The results suggest that children with ALLA(−) null-ALL have a poorer prognosis than those who are ALLA(+).