Current issues in the management of children with acute lymphocytic leukaemia

Seroconversion status after single dose and double doses of varicella vaccination in children with leukemia

Although varicella is a benign self-limiting disease in healthy children, it can be fatal when it occurs in immunocompromised hosts. Despite that immunosuppressed children are suggested to require 2 doses of vaccine to achieve seroconversion, conflicting results are reported in the literature. The aim of this study was to investigate the seroconversion status and mean antibody titers at first year after single dose and double doses of varicella vaccination in acute lymphoblastic leukemia patients. Patients with leukemia in remission for at least 1 year who were seronegative for varicella-zoster virus immunoglobulin G (IgG) were vaccinated. Titers above the cutoff level (0.65) were accepted as seroconversion. Seventeen patients were vaccinated with single dose whereas 24 patients were vaccinated with double doses. Mean prevaccination antibody titers were 0.56 ± 0.05 in patients with single dose and 0.51 ± 0.08 in patients with double doses (P > .05, Student t test). The mean antibody titers at first year were 0.61 ± 0.05 in patients with single-dose vaccination (P > .05, Wilcoxon signed-rank test) and 1.48 ± 0.04 in patients with double doses (P < .001, Wilcoxon signed-rank test). Seroconversion after single-dose vaccination was achieved in 29% of patients (n = 5/17) and in 75% of patients with double doses (n = 18/24) at first year (P = .004, chi-square test). These results suggest that seroconversion after single-dose vaccination might not persist at first year in malignancy patients. Double doses should be applied in order to provide long-term seroconversion.

Between remission and cure: patients, practitioners and the transformation of leukaemia in the late twentieth century

OBJECTIVES

During the course of the 1960s and 1970s, acute leukaemia in childhood ceased to be invariably fatal and was recategorized as curable. The meaning of cure in this case, however, was problematic, as it was impossible for physicians to be certain that cancer would not return. This paper uses historical methods to explore how remission was understood by families with children with acute leukaemia during the period in which the first cures were announced, roughly 1972-77.

METHODS

These comprised documentary analysis of records of the Medical Research Council's leukaemia working parties, published papers and letters on treatments for childhood leukaemia, and interviews with eight UK paediatric oncologists practising in UK hospitals in the 1960s and 1970s.

RESULTS

Two approaches to defining 'cure' in leukaemia can be identified. The first relied on statistical assessment of survival rates. I argue that the concept of 'indefinite remission' came to serve for researchers and clinicians as a proxy measure of cure. However, the concept of 'indefinite remission' left many patients and their families quite uncertain as to whether a cure had really happened. A second approach to defining cure therefore developed. Faced with uncertainty, patients, parents and psychologists sought to develop alternative measures of success--including the notion of 'psychological cure'--that brought forward the moment of cure and its relief.

CONCLUSIONS

Changing conceptualizations of leukaemia shaped and were shaped by negotiations over the meaning of 'remission' and 'cure'. On the one hand, the statistical definition of cure was not available for years. On the other hand, psychological cure could begin from the time of first remission, even if medical absolution was not available for years.

Heterogeneity of T cell lymphoblastic leukaemias

Twenty eight out of 170 consecutive cases of acute lymphoblastic leukaemia (ALL) were examined. They were of T cell origin, with the following distribution: seven (28%) cases had pre-T or prothymic features; nine (36%) cases showed early thymocytic features, six (24%) had cortical features; and three (12%) had a "mature" phenotype. The remaining three cases could not be sub-classified. A striking finding was that pre-T ALL differed from intrathymic ALL not only in the absence of both E rosettes and intrathymic differentiation antigens, but also in the expression of two non-lineage specific antigens HLA-DR and CD10. Both antigens appear in the bone marrow from the very first stages of lymphoid differentiation, implying that the origin for pre-T ALL is bone marrow. A comparison of the clinical features of pre-T and thymic ALL showed that pre-T ALL disease showed a pattern more similar to non-T ALL disease: a lower incidence of mediastinal mass, absence of extrahaematopoietic disease, lower white cell counts and haemoglobin concentrations, and a higher incidence of bone pain. No obvious difference in response to treatment was apparent. The results show that T-ALL is not only a heterogeneous immunological group but also suggest that it may have different origins: bone marrow for pre-T ALL and the thymus for thymic ALL.

The value of the immunological subtypes and individual markers compared to classical parameters in the prognosis of acute lymphoblastic leukemia

The value of the immunophenotypical subtypes and individual markers was compared with classical parameters in the prognosis of 150 patients with acute lymphoblastic leukemia (ALL). Regarding the immunophenotype, common-ALL had a better prognosis than T-ALL in the children's group. However, in adults the situation was different since both null and T-ALL patients had longer survival rates than the common pre-B group. Moreover, several individual markers add interesting prognostic information, either in ALL as a whole group or within the different immunophenotypes. Thus, the expression of CD10 and TdT had a significantly favourable influence in the outcome of the whole series of patients; within the T-ALL, those cases positive for CD10 also had a longer median survival (33 versus 17 months). In addition, in the common ALL patients group the expression of a relatively mature B marker--CD20--appeared to have a favourable prognosis (27 versus 13 months). Other non lineage specific markers, such as CD9 and CD38 did not seem to influence survival. Regarding the more conventional parameters, our data suggest that the classical age prognostic classification in children (less than 15 years) and adults can be improved using two cut-off points at 11 and 35 years. Moreover, the multivariate analysis showed that this variable, together with FAB morphology and WBC counts were the best combination of parameters for predicting survival. The present study shows that although the immunophenotype helps us in understanding the biological heterogeneity of ALL, having also prognostic implications, there are other clinical and hematological features that yield stronger prognostic information.

Species-specific therapy of acute lymphoid leukemia

In the past 10 years immunophenotyping of ALL has been demonstrated to be useful for selecting and scheduling chemotherapy. Different drug regimens are now used for T-cell and B-cell ALL than for non-T non-B ALL with the result that survival and cure of T-cell and B-cell ALL have been considerably improved. The use of different drug regimens for different immunophenotypic varieties of non-T non-B ALL is being tested. "Prognostic factors" of ALL are artifacts of data analysis and treatment and should no longer be used for guiding treatment. The administration of all-inclusive multiple-drug therapy to all patients with ALL regardless of species should also be abandoned. Minimally effective drugs can interfere with dosage and continuity of more effective drugs, and can result in side effects and sequelae that increase the mortality and morbidity of treatment. Since acute leukemias are genetic disorders of hematopoiesis the future direction of leukemic therapy is toward genetic targeting.

Survival of twenty-two months in a patient with primary plasma cell leukaemia treated with melphalan and prednisolone

In the majority of cases plasma cell leukaemia is a rapidly fatal disease with a mean survival time of five months. There have been reports of increased survival using various regimens of chemotherapy although most cases eventually relapse. We describe a patient with primary plasma cell leukaemia who responded to a combination of oral melphalan and prednisolone with control of the disease in the bone marrow but relapsed with extramedullary disease in the central nervous system and testes, and died 22 months after diagnosis. Melphalan poorly penetrates the central nervous system and its testicular penetration is unknown.

Cytosine arabinoside/cyclophosphamide pulses during continuation therapy for childhood acute lymphoblastic leukemia. Potential selective effect in T-cell leukemia

One hundred seventy-seven children with acute lymphoblastic leukemia (ALL) were admitted to a study designed to determine whether pulses of cytosine arabinoside (ara-C) and cyclophosphamide (cyclo) would improve disease-free survival (DFS). All patients received vincristine, prednisone, and asparaginase for remission induction, CNS prophylaxis with cranial irradiation and intrathecal methotrexate, and continuation therapy with 6-mercaptopurine plus methotrexate. Forty-seven of 101 patients with non-T ALL and 18 of 26 patients with T-cell ALL received ara-C/cyclo pulses every eight weeks during continuation therapy. The age, sex, and initial white cell count distributions were similar in both treatment groups. Patients with non-T-cell ALL had similar DFS with or without ara-C/cyclo pulses (36% versus 48%; P = 0.32). Ara-C/cyclo pulses significantly improved DFS in children with T-cell ALL (36% versus 0%; P = 0.015). Toxicities of the ara-C/cyclo pulses included reversible pancytopenia, drug induced fever, fever associated with neutropenia, and death in one patient from systemic candidiasis while neutropenic. This is the first clinical evidence to indicate that the combination of ara-C/cyclo used during continuation therapy is selectively beneficial in T-cell ALL.