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The molecular basis of acute lymphoblastic leukemia (ALL) of both B-cell and T-cell lineages seems better understood using polymerase chain reaction (PCR) methods. The analysis of clone-specific junctional regions of rearranged genes for both Immunoglobulin (Ig H) and T-cell receptor (TcR) is the most sensitive tool for detection of minimal residual disease (MRD) in ALL. Because of the heterogeneity of all ALL patients examined in several studies, the detection of MRD at different times of treatment has not as yet been correlated with disease outcome. In contrast, T-ALL is a homogeneous disease characterized by expansion of a single clone showing a specific Rearranged junctional region of TcR delta and/or gamma genes. The use of a clone-specific probe allows detection of residual leukemia throughout treatment. However, 60 % of patients with T-ALL relapse during treatment or towards the end of therapy, with resurgence of the original leukemic clone. It is possible that the detection of MRD at a specific time-point after diagnosis, as well as at the beginning of maintenance, may help to identify a group of T-ALL patients at high risk of relapse. The correlation between detection of MRD and treatment phase may be used in the future to evaluate whether treatment regimens can be improved allowing for stratification, based on PCR-mediated detection of MRD.

Expression of fetal hemoglobin (Hb F) is under polygenic control involving determinants both linked and unlinked to the beta-globin gene cluster on chromosome 11. Variations in the DNase I-hypersensitive site 2 of the locus control region (LCR-HS2) and a C --> T change at position -158 from the Ggamma-gene (detected as an XmnI polymorphism) correlate with the high level of Hb F expression in patients with sickle-cell anemia and beta-thalassemia. Interpretation of data under these conditions of anemic stress is difficult because the preferential survival of Hb F-containing erythrocytes (F-cells) may not reflect the true status of Hb F expression. We investigated the relationship between these markers and Hb F expression in terms of F-cell levels in 48 unrelated non-anemic AS heterozygotes from Sicily. The betaS-chromosome of all these individuals was of the Benin haplotype and they differed only by their betaA chromosomes. We demonstrate that F-cell expression is more strongly associated with LCR-HS2 polymorphism than with XmnI polymorphism. The observed association between XmnI polymorphism and Hb F expression is very likely to be due to linkage disequilibrium with LCR-HS2 sequences.

The aims of this study were twofold: (1) to assess the marrow of patients with T-lineage acute lymphoblastic leukemia (T-ALL) for the presence of molecular residual disease (MRD) at different times after diagnosis and determine its value as a prognostic indicator; and (2) to compare the sensitivity, rapidity, and reliability of two methods for routine clinical detection of rearranged T-cell receptor (TCR). Marrow aspirates from 23 patients with T-ALL diagnosed consecutively from 1982 to 1994 at the Division of Pediatric Hematology and Oncology, University of Catania, Italy, were obtained at diagnosis, at the end of induction therapy (6 to 7 weeks after diagnosis), at consolidation and/or reinforced reinduction (12 to 15 weeks after diagnosis), at the beginning of maintenance therapy (34 to 40 weeks after diagnosis), and at the end of therapy (96 to 104 weeks after diagnosis). DNA from the patients' marrow was screened using the polymerase chain reaction (PCR) for the four most common TCR delta rearrangements in T-ALL (Vdelta1 Jdelta1, Vdelta2 Jdelta1, Vdelta3 Jdelta1, and Ddelta2 Jdelta1) and, when negative, further tested for the presence of other possible TCR delta and TCR gamma rearrangements. After identification of junctional rearrangements involving V, D, and J segments by DNA sequencing, clone-specific oligonucleotide probes 5' end-labeled either with fluorescein or with [gamma-32P]ATP were used for heminested PCR or dot hybridization of PCR products of marrows from patients in clinical remission. For 17 patients with samples that were informative at the molecular level, the estimated relapse-free survival (RFS) at 5 years was 48.6% (+/-12%). The sensitivity and specificity for detection of MRD relating to the outcome were 100% and 88.9% for the heminested fluorescence PCR and 71.4% and 88.9% for Southern/dot blot hybridization, respectively. Predictive negative and positive values were 100% and 90.7% for heminested fluorescence PCR, respectively. The probability of RFS based on evidence of MRD as detected by heminested fluorescence PCR at the time of initiation of maintenance therapy was 100% and 0% for MRD-negative and MRD-positive patients, respectively. Thus, the presence of MRD at the beginning of maintenance therapy is a strong predictor of poor outcome, and the molecular detection of MRD at that time might represent the basis for a therapeutic decision about such patients. By contrast, the absence of MRD at any time after initiation of treatment strongly correlates with a favorable outcome. The heminested fluorescence PCR appears to be more accurate and more rapid than other previously used methods for the detection of residual leukemia.

Sicily, at the center of the Mediterranean, has been the meeting place of Eastern and Western civilizations, and in the Sicilian population the presence of many different alterations in the globin gene clusters can surely be considered testimony of past colonizations. From 1975 to 1994, 100,000 Sicilian subjects were screened by us to monitor the presence of hemoglobin (Hb) structural variants. In this paper we present the data gathered, emphasizing the high incidence (2.5%) of carriers of at least one abnormal Hb, and the great heterogeneity of globin molecular defects on the island. Twenty-six different mutations were identified: the most common occur in the beta-globin gene (beta(S), beta(C), deltabeta(Lepore), beta(G-San José), beta(O-Arab), but also quite frequent is the mutated allele alpha(J-Oxford). The chromosome haplotypes associated with some of them were characterized. Two uncommon Hbs, Copenhagen and D Punjab, and some 18 rare variants complete the wide spectrum of structural alterations of globin genes in Sicily. We think they are de novo mutations prevalently. It is not possible to exclude that the presence of a few of them is related to migratory phenomena, particularly from North Africa and East Asia. Numerous thalassemic alleles complete the picture of globin gene mutations in Silicy.

The present trial was designed to test the effects of G-CSF on the duration of the second phase of induction chemotherapy in children with newly diagnosed acute lymphoblastic leukemia (ALL). A total of 32 patients were assigned randomly to a group that received (14 patients; group A) or a group that did not receive (18 patients; group B) G-CSF (10 g/kg/day subcutaneously and daily) throughout of the second phase of induction therapy. One of 14 (7.1%) patients in group A and 2 of 18 (11.1%) patients in group B completed the course of chemotherapy within the planned time. The median length of this phase was 37 days (range, 29 to 65; mean, 40; SD, 8.6) for patients in group A and 36 days (range, from 29 to 55; mean, 38; SD, 7.4) for those in group B, and the difference was not statistically significant. The number of days during which patients had granulocyte counts of less than 2 x 10(9)/l, the number of febrile episodes of unknown origin, the number of bacterial and fungal infections and the number of days of hospitalization did not differ in a statistically significant manner between the two groups. Our data suggest that G-CSF supportive therapy may be unnecessary in children with neutropenia of short duration, for whom the risk of infection is low.

Purpose: As part of a study on the pharmacokinetics associated with the administration of asparaginase (ASNase) from Erwinia to the CNS, we determined the levels of asparagine in the CSF of children with acute lymphoblastic leukemia (ALL)., Patients and Methods: Twenty children received eight standard doses of intramuscular ASNase (10,000 IU/m2) every 3 days as part of induction therapy. In the postremission phase of therapy, the children were randomized to receive either 20 courses of high-dose intramuscular ASNase (25,000 IU/m2) weekly (n = 8) or four courses of standard-dose intramuscular ASNase (10,000 IU/m2) every 3 days (n = 12)., Results: All patients had detectable levels of L-asparagine in the CSF at the time of diagnosis. The levels of L-asparagine in CSF were undetectable in 15 of 20 (75%) and in seven of 19 (36.8%) children 3 and 5 days, respectively, after administration of standard-dose ASNase. After administration of high-dose ASNase, the levels of L-asparagine in the CSF were undetectable in five (62.5%) and two (25%) of eight children after 3 and 5 days, respectively., Conclusion: In this study 60% to 70% and 25% to 35% of children had complete depletion of L-asparagine from the CSF after 3 and 5 days, respectively, after administration of both schedules of ASNase from Erwinia. In the remaining patients, administration of ASNase may have resulted in a suboptimal antileukemic effect at the CNS level.

Objectives: For several years, children in Sicily with acute lymphoblastic leukaemia have been treated locally at the University of Catania. We compared the results of locally treated children with the results obtained at other centres., Methods: The diagnosis of acute lymphoblastic leukaemia (ALL) was made in 78 children in the haematology and oncology division of the University of Catania, Sicily, From January 1987 to December 1992. Patients diagnosed before December 1990 were treated with the protocol ALL 87 including prednisone, vincristine, daunorubicine, L-asparaginase and intrathecal methotrexate. Total duration of treatment was 25-26 months. For patients diagnosed after December 1990, the protocol 90-91 used the same drugs for induction and three intrathecal drugs (methotrexate, cytarabine and prednisone) as well as cyclophosphamide to prolong induction in intermediary risk patients. Only high risk patients received cerebral irradiation. Total duration of treatment was 2 years. Full follow-up data were available for 76 patients., Results: Survival rate without relapse was 66% and the 5-year survival rate was 82.7%. These results were comparable with those published by other international groups. In addition, particular attention was given to psychological support to decrease the deleterious effects of both the disease and the treatment protocols., Conclusion: These results demonstrate that ALL children can be cared for locally in Sicily without risking poorer outcome. It would be preferable to treat these children as near as possible to their area of residence in order to diminish the psychological trauma resulting from long-term hospitalization far from their family.

A multivariate survival analysis including gender, age, log white blood cell (WBC) count, liver and spleen size at diagnosis, mean log WBC count during maintenance therapy, and the prescribed cumulative doses of 6-mercaptopurine (6-MP), methotrexate (MTX), vincristine (VCR), and prednisone (PDN) during maintenance therapy was performed on 53 children with average-risk acute lymphoblastic leukemia (ALL). The 6-MP cumulative dose prescribed during maintenance therapy resulted in the most important statistically significant independent prognostic factor. Patients who received less than the median cumulative dose of 6-MP (86% of planned protocol dose) fared significantly worse than the other patients, regardless of WBC count at diagnosis, gender, age, and other factors studied. Therefore, 6-MP cumulative dose during maintenance therapy may be the critical factor for effective maintenance therapy in childhood ALL.

A group of 90 patients with acute lymphoblastic leukaemia (ALL) in first continuous complete remission (CCR), admitted in our hospital between January 1986 and September 1992, were tested for the presence of antibodies against hepatitis C virus (HCV), antibodies against hepatitis B virus and antibodies against HIV-1 during maintenance therapy or thereafter. They were compared with a group of 71 children with other malignancies in first CCR who had been diagnosed consecutively from January 1986 to September 1992. No patient with ALL or any other malignancy was found to be positive for hepatitis B surface antigen or HIV-1. HCV-specific antibodies were detected in 28 out of 87 children (32.1%) with ALL and in 4 out of 44 patients (9%) with malignancies other than ALL who had received at least one transfusion of blood or platelets (P < 0.01). HCV-specific antibodies were also detected in one out of three untransfused children with ALL but in none of the untransfused children with malignancies other than ALL. HCV-specific seropositivity influenced the management of children with ALL during maintenance therapy. In fact, as a result of abnormal liver function tests, maintenance therapy had to be suspended significantly more often in the case of HCV-seropositive patients with ALL than in HCV-seronegative ones. Despite the high morbidity during maintenance therapy, chronic liver disease (CLD) was uncommon in both groups: five children with ALL (17.2% of HCV-seropositive children) and one child with a malignancy other than ALL (25%) had CLD.(ABSTRACT TRUNCATED AT 250 WORDS)

Growth impairment and growth hormone (GH) deficiency have been reported in children treated for acute lymphoblastic leukaemia (ALL). We have studied growth and GH secretion in a group of 50 patients, affected by ALL, during a 2- to 5-year period after diagnosis, and in 12 "long-term-survivors". We observed a significant decrease in growth velocity during the 1st year (in particular during the first 6 months) of therapy and a catch-up growth after the end of therapy. "Long-term survivors" did not exhibit a significant reduction of height standard deviation score (SDS), as compared to height SDS at diagnosis. None of the patients showed GH deficiency. Our data indicate that chemotherapy significantly affects growth of patients treated for ALL, whereas radiotherapy-at the doses used in this study-does not induce GH deficiency, at least not within 9 years after diagnosis.

Hematological data are presented for an adult Sicilian patient with a mild Hb S-beta(+)-thalassemia caused by a C-->T mutation at position -92 of the beta promoter. This mutation was identified by sequencing of amplified DNA and was confirmed by dot-blot analysis with specific probes. A comparison of levels of Hb S and Hb A in Hb S-beta-thalassemia patients with different beta-thalassemia alleles showed great variations; the highest level of Hb A (45%) was recorded in the patient with Hb S-beta(+)-thalassemia [-92(C-->T)] and the lowest (approximately 13%) in patients with Hb S-beta(+)-thalassemia [IVS-II-745 (C-->G)]. Clinical severity is directly related to the level of Hb A present.

A number of genetic or acquired conditions in which hemoglobin anomalies occur without detectable modifications of globin genes are reviewed. They include increased fetal hemoglobin (alpha 2 gamma 2), variations in hemoglobin A2 concentration, the presence of Hb H (beta 4), Bart's Hb (gamma 4), Hb Köelliker, glycosylated, carbamylated and acetylated hemoglobins.