We prospectively compared neuropsychologic functioning and clinical indicators of neurotoxicity in 49 consecutive childhood leukemia patients in long-term continuous complete remission (CR) who had received two different regimens of CNS prophylaxis by random assignment. Twenty-three patients were treated with 1,800 cGy cranial radiation and intrathecal methotrexate (RT group) and 26 with parenteral methotrexate only (MTX group). Over half of the RT group had somnolence syndrome, and four developed cerebral calcifications late in their clinical course. Abnormal electroencephalograms (EEGs) were seen in 15 patients in the MTX group, and six had early, transient white-matter hypodensities apparent on computed tomographic (CT) scans. Mean scores on standard tests of intelligence and academic achievement, administered after remission induction and again at a median of 6 years after treatment cessation, did not differ significantly between the two groups. However, statistically significant decreases in overall and verbal intelligence quotients (IQs) and in arithmetic achievement were found within both treatment groups. Sixteen of 26 in the MTX group and 14 of the 23 in the RT group had clinically important decreases (greater than or equal to 15 points) on one or more neuropsychologic measures. These changes did not correlate with findings on CT scans, EEGs, or other clinical signs of neurotoxicity. We conclude that 1,800 cGy cranial radiation and parenteral methotrexate, as used in this study, are associated with comparable decreases in neuropsychologic function.

Cellular DNA content distributions of propidium-iodide-stained bone marrow blasts were determined by flow cytometry (FCM) for 225 untreated children with acute leukemia and were correlated with leukemia cell phenotype and karyotype. Aneuploidy of the primary malignant stem line was detected in 54 cases (24%): 51 hyperdiploid and 3 hypodiploid. A second stem line with approximately twice the DNA content of the primary stem line was recognized by FCM in 28 cases (23 ALL, 5 ANLL) and may be an important source of leukemia cell heterogeneity. The degree of DNA content abnormality detected by FCM was highly correlated (r = 0.98) with the number of whole chromosome gains or losses in the leukemia karyotype. Aneuploidy detectable by FCM was more frequent in acute lymphoblastic leukemia (ALL) (52 of 173, 30.1%) than in acute nonlymphoblastic leukemia (2 of 52, 3.8%) (p less than 0.001). In the ALL group, aneuploidy was significantly correlated with the cell surface expression of common ALL antigen: 46 of 127 antigen-positive cases were aneuploid compared to 6 of 46 antigen-negative cases (p less than 0.003). Only 2 of 21 cases of T-cell ALL without common ALL antigen had detectable aneuploidy, which was significantly less than in the common ALL group (p = 0.02). The median percentage of cells in S- phase was significantly greater for B-cell and erythrocyte rosette- positive T-cell ALL, than for the other phenotypic subgroups. We conclude that aneuploidy and S-phase cell percentage are correlated with the state of leukemia cell differentiation. The biologic basis for the correlation is not established, but may be linked to the process of malignant transformation.

We assessed the influence of an initial isolated meningeal relapse on treatment outcome in 839 children with acute lymphoblastic leukemia (ALL) who were admitted to St Jude Children's Research Hospital (Memphis) from mid-1967 through mid-1979. The patients were entered in a series of five clinical trials (Total Therapy Studies V through IX), each designed to test one or more modifications of treatment for ALL. Two groups were compared: 699 children who received CNS prophylaxis (2,400-rad craniospinal irradiation or 2,400-rad cranial irradiation plus intrathecal methotrexate) v 56 who did not. Our results, obtained with a time-dependent covariate model and a matching technique, indicate a 2 to 3.5-fold increase in the risk of hematologic relapse or death among patients who experienced an isolated CNS relapse compared with similar patients (matched for leukocyte count and length of complete remission) who remained free of CNS involvement. Of the 107 children with an initial isolated CNS relapse, 89 (83%) have died or have had a subsequent relapse. There was no detectable difference in the rate of hematologic relapse or death after a CNS relapse between patients who had received preventive therapy and those who had not. We conclude that CNS prophylaxis is important both for the prevention of initial CNS leukemia and for reducing the risk of hematologic relapse or death subsequent to a CNS relapse.

Bone marrow lymphoblasts from 109 children admitted with untreated acute lymphoblastic leukemia (ALL) were tested for spontaneous rosette formation with sheep erythrocytes. Twenty-six children (24%) had lymphoblasts that formed rosettes (E+). Of 13 initial clinical characteristics, 8 were significantly associated with E+ lymphoblasts: mediastinal enlargement (86% of patients E+), leukocyte counts over 100 X 10(9)/liter (65% E+), nodes greater than 2 cm in any diameter (65% E+), age over 5 yr (46% E+), hemoglobin over 8 g/dl (44% E+), hepatomegaly greater than 5 cm (38% E+), boys (35% E+), and lymph node enlargement outside of the cervical area (28% E+). Spleen size, initial platelet counts, and periodic acid-Schiff scores did not distinguish E+ from E- patients. Since few patients were black and few presented with central nervous system leukemia, the association of these two characteristics with E+ blasts could not be determined. A hierarchical classification scheme and a linear logistic regression model were used to define the patterns of characteristics associated with E+ lymphoblasts. The initial clinical characteristics and the poorer course of E+ patients suggest that ALL comprises at least two biologically and clinically distinct types. The E+ ALL may result from a leukemic transformation of a non-Hodgkin lymphoma.

We studied the arrangement of the immunoglobulin heavy chain genes by Southern blot analysis of DNA freshly obtained from marrow blast cells of 14 children with T cell acute lymphoblastic leukemia (T-ALL) using probes to the C mu and JH gene segments: At least one of the C mu-gene alleles was rearranged in three cases. In two of these, one C mu gene had the germ-line configuration and one was rearranged, whereas both alleles were rearranged in the third case. In one case, a rearranged heavy chain gene hybridized to the C mu-region probe, but not to the JH probe, indicating that the entire JH region had been deleted. These results demonstrate that immunoglobulin heavy chain gene rearrangements are not restricted to B lineage lymphoproliferative diseases in humans.