Treatment of occult or late overt testicular relapse in children with acute lymphoblastic leukemia: a Pediatric Oncology Group study.

PURPOSE: The Pediatric Oncology Group (POG) designed a randomized two-arm protocol (8304) to improve the survival of children with acute lymphoblastic leukemia (ALL) who experience an isolated testicular relapse and to evaluate the efficacy of teniposide (VM-26) and doxorubicin as intensification agents during second remission. The outcome and toxicity observed in 80 patients with isolated testicular leukemia treated on POG 8304 are presented. PATIENTS AND METHODS: The following are common features of POG 8304: (1) remission reinduction therapy with vincristine, prednisone, and doxorubicin; (2) bilateral testicular irradiation (2,600 cGy) during reinduction therapy; (3) CNS prophylaxis with intrathecal hydrocortisone, methotrexate (MTX), and cytarabine (Ara-C); and (4) continuation therapy (for 80 weeks) with alternating 6-week cycles of oral mercaptopurine (6-MP)/MTX and intravenous vincristine and cyclophosphamide. Treatment differences consisted of pulses (administered every 7 weeks) of either prednisone and doxorubicin (arm 1) or VM-26 and Ara-C (arm 2) during continuation therapy and a 4-week late intensification phase with either vincristine, prednisone, and doxorubicin (arm 1) or VM-26 and Ara-C (arm 2). RESULTS: Fifty-five boys with ALL had isolated microscopic testicular leukemia detected by an elective biopsy at completion of initial treatment, and 25 had a late (greater than or equal to 6 months off-therapy) isolated overt testicular relapse. All patients with overt testicular leukemia attained a second clinical remission, and no patient with microscopic testicular leukemia progressed during reinduction. Of 42 patients on arm 1, 11 have relapsed compared with 18 of 38 patients on arm 2 (log-rank analysis, P = .22), indicating no significant difference between an anthracycline and an epipodophyllotoxin-Ara-C combination in the treatment of testicular leukemia. The overall 4-year event-free survival (EFS) among boys with occult testicular relapse was 53% +/- 8%. Age greater than 10 years at initial diagnosis, a WBC count greater than 50,000/microL at diagnosis, and black race were associated with a worse outcome. The 4-year EFS for boys with a late overt testicular relapse was 84% +/- 10%, and these patients fared significantly better than patients with occult disease (P = .007). CONCLUSION: The treatment approach reported here can secure a prolonged second remission in many patients with occult or late overt testicular leukemia.

Phase II study of 13-cis-retinoic acid in pediatric patients with acute nonlymphocytic leukemia--a Pediatric Oncology Group study.

Forty-one patients with refractory acute non-lymphocytic leukemia (ANLL) in relapse were treated with 13-cis-retinoic acid (cRA) as salvage therapy. The cRA was given as a single oral dose of 100 mg/m2/day for 4 weeks. One patient achieved a complete remission and two patients achieved a partial remission with reduction of the bone marrow blast count from 40 to 20% after the first course. We recommend further study of cRA in combination with other agents in the treatment of ANLL in children.

Effects of iron, copper, zinc, calcium, and magnesium on human lymphocytes in culture.

The effects of simultaneous changes of calcium, magnesium, iron, copper, and zinc concentrations were evaluated in normal human T and B lymphocytes, cultured in cation-depleted media. Optimal concentrations for thymidine incorporation (TI) in both cell populations were Fe and Zn 15 microM and Cu 5 microM; for T cells Ca 2 mM and Mg 4 mM; for B cells Ca 4 mM and Mg 6 mM. TI decreased with increasing molarity of cations and the decrease was particularly apparent with Cu. Minimal amounts of Ca and Mg (0.5 mM) were necessary for growth, even in presence of optimal concentrations of Fe, Cu, and Zn. Fe and Cu showed synergistic stimulatory effects at low concentrations and synergistic inhibitory effects at high concentrations. Antagonism between Fe and Zn, Cu and Zn, and Ca and Zn was also demonstrated. CD4/CD8 increased with PHA stimulation in presence of Zn, and decreased with ConA stimulation in presence of Zn or Fe. The results demonstrate: (1) the relationship and interdependence of Fe, Cu, and Zn concentrations in modulating the growth of normal lymphocytes; (2) the stimulatory effects of Fe on B cells and Zn on CD8 positive cells; (3) the inhibitory effect of Cu at concentrations lower than those of Fe and Zn; (4) the requirement of Ca and Mg in certain concentration and ratio for the action of the other cations; and (5) the Ca and Mg requirement for the growth of B cells higher than T cells.

Observations on the use of a cation exchange resin for the preparation of metal-depleted media for lymphocyte culture.

A chelating resin specific for divalent cations (Chelex) was used to prepare metal-depleted media for lymphocyte culture. A batch procedure (resin in pH 7.4 phosphate buffer/specimen, 1:1) removed 70-80% of iron, 77-87% of copper and 88-98% of zinc, calcium and magnesium. At variance with other reports, when a resin/specimen ratio of 1:4 was used, iron chelation decreased to 40%, whereas other cation chelation remained unchanged. Best chelation for iron and calcium was obtained at pH 5-6.4; for copper, zinc and magnesium, at pH 7.4-8.0. During the procedure protein content decreased by 8-10%; arginine and lysine by 80%; asparagine, cystine, tyrosine and phenylalanine by 60%, other amino acids by 35%. These new data suggest that cation-depleted media prepared with Chelex may be used to study the effects of cations on lymphocytes in culture, provided that the most appropriate pH and resin/specimen ratio are selected and adequate amino acid replacement is performed. Results on normal human lymphocytes are reported.

Copper, zinc, and iron in normal and leukemic lymphocytes from children.

Copper, zinc, and iron were quantitated in the serum and lymphoid cells of the peripheral blood of healthy children and children with acute lymphocytic leukemia. Copper and iron concentrations in serum and cells were significantly higher and zinc concentration in the cells significantly lower in leukemic patients than in healthy donors, whereas the increase of zinc in the serum was not significant. The concentration of all minerals was higher in T-cell enriched preparations. There was a significant correlation between copper and iron and between copper and zinc, but not between iron and zinc in normal and leukemic lymphocytes. No correlation was demonstrated among the three minerals in the serum. There were no significant differences associated with ethnicity, age, sex, type of leukemia, or number of leukemic cells. However, a group of five children with non-B-, non-T-cell acute lymphocytic leukemia, nonreactive skin tests, and low serum immunoglobulins had high concentrations of copper and iron and low concentration of zinc in their leukemic cells. Since copper, zinc, and iron are associated with lymphocyte maturation and regulation of immune function, these new data will provide a tool for the study of the relationship between changes in concentrations of these metals and the modification of the immune response often present in hematologic cancers.

Zinc deficiency and blood lymphocyte function with sickle cell disease.

A relationship between zinc deficiency and lymphocyte function in children with sickle cell disease (SCD) has been suggested. Number and function of B and T lymphocytes were assessed in 3 matched groups of children: normal subjects with Hb A and normal zinc; patients with SCD; and normal zinc (SCD-N); and patients with SCD and decreased zinc (SCD-D). Percentages of B and T cells, response to cutaneous antigens and increases in tetanus antibody titres were similar among all groups. Absolute numbers of WBC, lymphocytes and B and T cells were markedly increased in SCD-N (p less than 0.001) and to a lesser degree in SCD-D (p less than 0.01). Controls and SCD-N had a normal response to all mitogens, which was not inhibited by SCD-D sera. SCD-D had a depressed response to PHA (p less than 0.001), which was not corrected by zinc addition in vitro. These findings indicate that B cell function and T cell-dependent delayed hypersensitivity are normal in children with SCD and are independent of body zinc status. They also suggest some abnormality of T helper cells in the presence of zinc deficiency, and in the absence of a demonstrable serum inhibitor.

Leukemia with a novel 4q11q rearrangement.

Translocation (4;11)(q21;q23) is characteristic of a distinct acute leukemic syndrome. We report an 8-wk-old male patient with the clinical features ascribed to t(4;11), but with an unusual chromosome rearrangement consisting of an insertion of the 11q23 band into the q21 region of chromosome #4.

Neutrophils and zinc in infection-prone children with sickle cell disease.

Neutrophils can be distinguished as EA negative (EA-N) or EA positive (EA+N), according to rosette formation with sheep erythrocytes. EA- neutrophils show a bactericidal activity 50% to 70% lower than EA+ neutrophils. Thirty children with sickle cell disease were studied during steady state and crises/infections, together with matched control children. EA+ and EA- neutrophils, zinc levels in the body, and frequency of previous bacterial infection were evaluated. Sixty percent of the patients (18/30) had zinc deficiency (zinc less than 8.5 micrograms/10(10) RBC): of this group, more than three fourths (14/18) had a high frequency of infections (greater than or equal to 3/yr) and most of those (11/14) also had an increased percentage of EA- neutrophils (80% to 85% v 35% to 45% in control subjects). Only 4/18 of patients with zinc deficiency had a low frequency of infections, and only one of these four had a higher percentage of EA- neutrophils. In patients with normal zinc levels (12/30 or 40%), only three had frequent infections, but only one of these had an increased percentage of EA- neutrophils. The number of EA+ neutrophils increased after stimulation with epinephrine or during crises/infections. In six patients with more pronounced zinc deficiency and more severe crisis/infection, a delay in the increase of EA+ neutrophils occurred and was corrected by treatment. These findings suggest that a higher percentage of neutrophils with less bactericidal activity in many children with sickle cell disease and zinc deficiency may be a factor in the higher incidence of infections noted in these patients, and zinc might play a role in the formation, release, and activity of neutrophils.

Trial of daunomycin in acute promyelocytic leukemia of childhood: a Southwest Oncology Group Study.

Children with acute promyelocytic leukemia were treated with aggressive daunomycin induction and 6-mercaptopurine and methotrexate maintenance. The remission rate was 8 out of 10 fully evaluable patients. Three are still alive up to 32 months. With vigorous induction therapy, occurrence of disseminated intravascular coagulation was rare. Only one case of DIC was seen in a child who had pseudomonas sepsis at time of diagnosis. Since current protocols are more aggressive, future chemotherapy include patients with acute promyelocytic leukemia.

Variation of activity of protein kinases in unstimulated and phytohemagglutinin-stimulated normal and leukemic human lymphocytes.

Cyclic adenosine 3':5'-monophosphate-dependent protein kinase (kinase A) and cyclic guanosine 3':5'-monophosphate-dependent protein kinase (kinase G) were assayed in lymphocytes of normal subjects, adults with chronic lymphocytic leukemia (CLL), and children with acute lymphocytic leukemia (ALL). There was a good correlation between the activity of the two kinases and the level of the corresponding cyclic nucleotides. This was true for cultured phytohemagglutinin-stimulated normal lymphocytes and CLL lymphocytes as well. Kinase A activity was low and kinase G activity was high in leukemic cells in the absence of the respective cyclic nucleotides [5 and 8 units (pmol 32P incorporated into histone per min per mg protein) for kinase A and 98 and 51 units for kinase G in ALL and CLL lymphocytes, respectively]. Upon addition of cyclic adenosine 3':5'-monophosphate and cyclic guanosine 3':5'-monophosphate in vitro, values for kinase A activity returned to normal (approximately 30 units), whereas those for kinase G increased further (212 units for ALL and 85 units for CLL lymphocytes; 22 units was the kinase activity for normal lymphocytes). These findings suggest that cyclic nucleotides achieve thetr specificity in the regulation of the cell, in part, through the activation of the dependent protein kinases and that both kinase A and kinase G may be functionally intact in leukemic cells.

HbE-beta-thalassemia associated with G6PD deficiency.

HbE, beta thalassemia, and G6PD deficiency were demonstrated in a 6-year-old Mexican-American child with anemia, jaundice, and delayed growth. The father was heterozygous for HbE, and the mother for beta-thalassemia and G6PD deficiency. The association of these three diseases should be included in the differential diagnosis of anemia in childhood, particularly after the recent influx of people form Southeast Asia into the United States.

Cerebral neuroblastoma with elevated nerve growth factor.

Cerebral neuroblastoma is often difficult to differentiate by clinical criteria from other central nervous system neoplasm. This report is of a young child with cerebral neuroblastoma and elevated nerve growth factor. This case illustrates the need for further studies into the usefulness of nerve growth factor in differentiating cerebral neuroblastoma from other central nervous system tumors.