Chronic lymphocytic leukemia

B-cell chronic lymphocytic leukemia risk in association with serum leptin and adiponectin: a case-control study in Greece

AIM

Leptin and adiponectin are two well-studied adipokines in relation to malignancies. In this study, we examined the association between leptin/adiponectin and risk of B-cell chronic lymphocytic leukemia (B-CLL), as well as the relationships between adipokines and several established prognostic factors of B-CLL.

METHODS

Ninety-five patients with incident B-CLL and 95 hospital controls matched on age and gender were studied between 2001 and 2007, and blood samples were collected. Leptin, total and high molecular weight adiponectin, and prognostic markers of B-CLL were determined.

RESULTS

Cases had a higher body mass index (BMI) than controls (p = 0.01) and lower levels of leptin (p < 0.01). Significantly more cases than controls presented a family history of lymphohematopoietic cancer (LHC) (p = 0.01). Higher serum leptin levels were associated with lower risk of B-CLL adjusting for age, gender, family history of LHC, BMI and serum adiponectin; the multivariate odds ratio comparing highest to lowest tertile was 0.05 (95% CI 0.01-0.29, p trend < 0.001); Adiponectin was not significantly different between cases and controls.

CONCLUSION

Leptin was found to be inversely associated with risk of CLL but in contrast to prior studies of CLL and hematologic malignancies, this study found no significant association between CLL and adiponectin.

A multinational study of health state preference values associated with chronic myelogenous leukemia

OBJECTIVES

Chronic myelogenous leukemia (CML) is a progressive, largely fatal cancer. Emerging treatments may prolong life; however, these result in additional monetary costs. Accurate estimation of their economic impact requires reliable estimates on preferences for health states. The purpose was to estimate preference weights from the general population in four developed countries for standardized health states experienced by persons with CML.

METHODS

Time trade-off preferences with a 10-year time horizon were elicited for CML-related health states using an interviewer-administered survey from convenience samples in Canada (n=103), the United States (n=74), the UK (n=97), and Australia (n=79). Standardized descriptions of seven CML-related health states (characterizing chronic, accelerated and blast phases, each with responding and nonresponding state, and adverse events of treatment) were derived in consultation with oncologists. Generalized linear models were used to estimate whether utilities, adjusted for age and sex, differed by country.

RESULTS

The mean age of the sample (n=357) was 45 years and 46% were male. Mean unadjusted preference values of CML-related health states ranged from 0.84 for "Chronic phase responding to treatment" to 0.21 for "Blast phase, not responding to treatment." For each phase, preferences were lower for the nonresponding state. After adjustment for age and sex, considerable variability was observed in mean preference values between countries.

CONCLUSION

These data quantify the deteriorating impact of CML disease progression and the impact of nonresponse to treatment. The study results add to evidence from other disease areas that systematic differences exist in preference values between countries.

Pathology of chronic lymphocytic leukemia: an update

Chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) is a clonal lymphoproliferative disorder characterized by proliferation of morphologically and immunophenotypically mature lymphocytes. CLL/SLL may proceed through different phases: an early phase in which tumor cells are predominantly small in size, with a low proliferation rate and prolonged cell survival, and a transformation phase with the frequent occurrence of extramedullary proliferation and an increase in large, immature cells. Although some patients with CLL have an indolent disease course and die after many years of unrelated causes, others have very rapidly disease progression and die of the disease within a few years of the diagnosis. In the past few years, considerable progress has been made in our ability to diagnose and classify CLL accurately. Through cytogenetics and molecular biology, it has been shown that CLL and variants are associated with a unique genotypic profile and that these genetic lesions often have a direct bearing on the pathogenesis and prognosis of the disease. Similarly, the development of antibodies to new biologic markers has allowed the identification of a unique immunophenotypic profile for CLL and variants. Moreover, accumulating evidence suggests that CLL cells respond to selected microenvironmental signals and that this confers a growth advantage and an extended survival to CLL cells. In this article, we will review the progress in the pathobiology of CLL and give an update on prognostic markers and tools in current pathology practice for risk stratification of CLL.

Economic evaluations of leukemia: A review of the literature

Objectives:Leukemia, together with lymphoma and multiple myeloma, are hematological malignancies, malignancies of the blood-forming organs. There are four major types of leukemia: acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), and chronic lymphocytic leukemia (CLL). There is a growing amount of literature of the health economic aspects of leukemia. However, no comprehensive review is yet performed on the health economic evidence for the disease. Hence, our aim was to review and analyze the existing literature on economic evaluations of the different types of leukemia.

Methods:A systematic literature search used electronic databases to identify published cost analyses and economic evaluations of leukemia treatments. After reviewing all identified studies, sixty studies were considered relevant for the purpose of the review.

Results:The identified studies were published after 1990, with a few exceptions. Many of the identified economic evaluations in leukemia, particularly for ALL and AML, may be defined as cost-minimization analyses, where only the costs of different treatment strategies are compared. In CML, a new treatment, imatinib, was introduced in 2001 and several cost-effectiveness analyses have since then been conducted comparing imatinib with previous first line treatments.

Conclusions:This review indicates that there is a shortage of cost-effectiveness information in leukemia. The introduction of new therapies will stress the need for new economic evaluations in this group of diseases. More information about the total costs, that is, including indirect costs, and quality of life effects would be valuable in future evaluations in leukemia.

Chronic lymphocytic leukemia: economic burden and quality of life: literature review

The purpose of this review was answer 2 main questions: what is the impact of chronic lymphocytic leukemia (CLL) on the patient's quality of life and how great is the economic burden of this disease on the health care payers and providers. Patients with CLL typically do not receive any treatment soon after the initial diagnosis. Although there is no known cure for CLL yet, when treated, the patients receive aggressive and expensive therapies (eg, chemotherapy or bone marrow transplantation). A rigorous and systematic literature review was performed of English-language articles published in 1990-2002. It was supplemented with additional articles published before 1990 for completeness and additional references to fill the gaps identified in the published medical literature. The literature on the quality of life (QOL) of CLL patients is very limited. We identified only 8 articles, and none of them analyzed the QOL in untreated CLL patients. Because CLL is a disease affecting adults, especially the elderly, all 8 studies measured the QOL in the adult population. QOL difficulties include fear of death and disability, problems gaining employment or health insurance, and fatigue. No specific leukemia or CLL instruments but general QOL instruments (eg, I-HRQL) were identified and some cancer-specific ones (eg, EORTC QLQ-C30, FACT-G, FACT Anemia, FACT-Fatigue). Interestingly, a FACT-Bone Marrow Transplant instrument exists, although we found no study on CLL that used it. Even the literature on the economic burden of CLL is very limited. We identified 13 studies on the cost of CLL: Most of them were cost-identification or cost-comparison studies, and 5 dealt with the cost-effectiveness of medical interventions to treat CLL. Cost drivers identified for CLL were the chemotherapy costs, intravenous immunoglobulin costs, transplantation costs, and costs associated with the differential staining cytotoxicity assay. We identified very few articles on the QOL of CLL patients and therefore cannot draw strong conclusions about the key QOL predictors. Nevertheless, patients with anemia were found to have a better QOL if they had higher hemoglobin counts and good response to erythropoietin treatment. The articles published seem to demonstrate that the older the age of the patient was, the poorer the QOL. The main cost drivers identified for CLL were related to the treatment chosen (eg, chemotherapy, bone marrow transplantation). There are hints that higher costs often result from the delivery of non-optimal therapy that leads to adverse events, infections, and drug resistance. In summary, the impact of this disease on the health care budget of the different health care providers and payers as well as on the patient's QOL is substantially unknown, calling for appropriate economic and QOL studies.

Alemtuzumab induces enhanced apoptosis in vitro in B-cells from patients with chronic lymphocytic leukemia by antibody-dependent cellular cytotoxicity

Alemtuzumab, a monoclonal anti-CD52 antibody has been shown to be highly effective in B-cell chronic lymphocytic leukemia, even in fludarabine-refractory disease. The mechanism of action is currently unknown, but may rely on complement-mediated cell lysis and antibody-dependent cellular cytotoxicity. The aim of this study was to assess the proapoptotic activity of alemtuzumab in chronic lymphocytic leukemia and to describe pathways potentially underlying this effect. Peripheral blood mononuclear cells from 21 chronic lymphocytic leukemia patients were treated in vitro in the absence of complement with fludarabine alone, alemtuzumab alone, or with the additional presence of a cross-linking anti-Fc-antibody. Apoptosis was quantified after 24 h by flow cytometry analysis. Expression of several pro- and anti-apoptotic proteins was determined at different time points. Apoptosis of peripheral blood mononuclear cells treated with alemtuzumab alone was significantly enhanced compared to untreated cells suggesting a minor potentially cytotoxic mechanism by direct signaling independent from antibody-dependent cellular cytotoxicity. The presence of a cross-linking anti-Fc-antibody induced the formation of cell clusters and enhanced apoptosis significantly suggesting a potential role of antibody-dependent cellular cytotoxicity in alemtuzumab induced apoptosis. Alemtuzumab activated a CD52-dependent signaling pathway which induced a significant increase in caspase 3 and 8 expression. Alemtuzumab significantly enhances apoptosis in chronic lymphocytic leukemia cells in vitro, especially in combination with a cross-linking anti-Fc-antibody, this effect being mediated by a caspase-dependent pathway.

The clinical and epidemiological burden of chronic lymphocytic leukaemia

The purpose of this literature review was to identify and summarize published studies describing the epidemiology and management of chronic lymphocytic leukaemia (CLL). Chronic lymphocytic leukaemia represents 22-30% of all leukaemia cases with a worldwide incidence projected to be between < 1 and 5.5 per 100,000 people. Australia, the USA, Ireland and Italy have the highest CLL incidence rates. Chronic lymphocytic leukaemia presents in adults, at higher rates in males than in females and in whites than in blacks. Median age at diagnosis is 64-70 years. Five-year survival rate in the USA is 83% for those < 65 years old and 68% for those 65 + years old. Hereditary and genetic links have been noted. Persons with close relatives who have CLL have an increased risk of developing it themselves. No single environmental risk factor has been found to be predictive for CLL. Patients are usually diagnosed at routine health care visits because of elevated lymphocyte counts. The most common presenting symptom of CLL is lymphadenopathy, while difficulty exercising and fatigue are common complaints. Most patients do not receive treatment after initial diagnosis unless presenting with clear pathologic conditions. Pharmacological therapy may consist of monotherapy or combination therapy involving glucocorticoids, alkylating agents, and purine analogs. Fludarabine may be the most effective single drug treatment currently available. Combination therapy protocols have not been shown to be more effective than fludarabine alone. As no cure is yet available, a strong unmet medical need exists for innovative new therapies. Experimental treatments under development include allogeneic stem cell transplant, mini-allogeneic transplants, and monoclonal antibodies (e.g. alemtuzumab against CD52; rituximab against CD20).

Results of the MRC pilot study show autografting for younger patients with chronic lymphocytic leukemia is safe and achieves a high percentage of molecular responses

We have assessed autologous stem cell transplantation after treatment with fludarabine in previously untreated patients with chronic lymphocytic leukemia (CLL). This study is the first to enroll previously untreated patients and follow them prospectively. The initial response rate to fludarabine was 82% (94 of 115 patients). Stem cell mobilization was attempted in 88 patients and was successful in 59 (67%). Overall 65 of 115 patients (56%) entered into the study proceeded to autologous transplantation. The early transplant-related mortality rate was 1.5% (1 of 65 patients). The number of patients in complete remission after transplantation increased from 37% (24 of 65) to 74% (48 of 65), and 26 of 41 patients (63%) who were not in complete remission at the time of their transplantation achieved a complete remission after transplantation. The 5-year overall and disease-free survival rates from transplantation were 77.5% (CI, 57.2%-97.8%) and 51.5% (CI, 33.2%-69.8%), respectively. None of the variables examined at study entry were found to be predictors of either overall or disease-free survival. Sixteen of 20 evaluable patients achieved a molecular remission on a polymerase chain reaction (PCR) for immunoglobulin heavy-chain gene rearrangements in the first 6 months following transplantation. Detectable molecular disease by PCR was highly predictive of disease recurrence. It is of concern that 5 of 65 (8%) patients developed posttransplant acute myeloid leukemia/myelodysplastic syndrome.

Reduced cell turnover in bovine leukemia virus-infected, persistently lymphocytotic cattle

Although nucleotide analogs like bromodeoxyuridine have been extensively used to estimate cell proliferation in vivo, precise dynamic parameters are scarce essentially because of the lack of adequate mathematical models. Besides recent developments on T cell dynamics, the turnover rates of B lymphocytes are largely unknown particularly in the context of a virally induced pathological disorder. Here, we aim to resolve this issue by determining the rates of cell proliferation and death during the chronic stage of the bovine leukemia virus (BLV) infection, called bovine persistent lymphocytosis (PL). Our methodology is based on direct intravenous injection of bromodeoxyuridine in association with subsequent flow cytometry. By this in vivo approach, we show that the death rate of PL B lymphocytes is significantly reduced (average death rate, 0.057 day(-1) versus 0.156 day(-1) in the asymptomatic controls). Concomitantly, proliferation of the PL cells is also significantly restricted compared to the controls (average proliferation rate, 0.0046 day(-1) versus 0.0085 day(-1)). We conclude that bovine PL is characterized by a decreased cell turnover resulting both from a reduction of cell death and an overall impairment of proliferation. The cell dynamic parameters differ from those measured in sheep, an experimental model for BLV infection. Finally, cells expressing p24 major capsid protein ex vivo were not BrdU positive, suggesting an immune selection against proliferating virus-positive lymphocytes. Based on a comparative leukemia approach, these observations might help to understand cell dynamics during other lymphoproliferative disease such as chronic lymphocytic leukemia or human T-cell lymphotropic virus-induced adult T-cell leukemia in humans.

Alemtuzumab

Alemtuzumab is an unconjugated, humanised, monoclonal antibody directed against the cell surface antigen CD52 on lymphocytes and monocytes. In noncomparative phase I/II studies in patients with B-cell chronic lymphocytic leukaemia (B-CLL) relapsed after or refractory to alkylating agents and fludarabine, intravenous (IV) administration of alemtuzumab 30 mg/day three times weekly for up to 12 weeks was associated with overall objective response (OR) rates of 21-59%. Combining alemtuzumab with fludarabine resulted in ORs >80%. In noncomparative studies in patients with previously untreated B-CLL, subcutaneous (SC) administration of alemtuzumab alone, or IV in combination with fludarabine, was highly effective, achieving OR rates of around 90%. IV alemtuzumab was active in patients with chemotherapy-resistant/relapsed T-cell prolymphocytic leukaemia, with reported OR rates of 24-76%. Alemtuzumab has been incorporated in novel conditioning regimens designed to facilitate stem cell transplantation in haematological malignancies. Adverse events with alemtuzumab are predictable and manageable. 'First-dose' flulike symptoms, frequently seen after IV infusion, can be managed by (pre)medication and minimised by dose escalation (or SC injection). Anti-infective prophylaxis is mandatory. Cytopenias are transient, although red blood cell and platelet support may be required.

The burden and outcomes associated with four leukemias: AML, ALL, CLL and CML

Given the recent advances in the treatment of hematologic malignancies and the many other treatments on the horizon, physicians and payers will be faced with the critical decisions of when to use new treatments in the clinical pathway and how to allocate healthcare resources. This review will provide an overall context for the clinical, economic and quality of life burden of leukemia, as well as provide cross-analysis among the four major types of leukemia: acute lymphocytic leukemia, chronic lymphocytic leukemia, acute myeloid leukemia and chronic myeloid leukemia.