Fludarabine and mitoxantrone for patients with chronic lymphocytic leukemia

Marine nucleosides: structure, bioactivity, synthesis and biosynthesis

Nucleosides are glycosylamines that structurally form part of nucleotide molecules, the building block of DNA and RNA. Both nucleosides and nucleotides are vital components of all living cells and involved in several key biological processes. Some of these nucleosides have been obtained from a variety of marine resources. Because of the biological importance of these compounds, this review covers 68 marine originated nucleosides and their synthetic analogs published up to June 2014. The review will focus on the structures, bioactivities, synthesis and biosynthetic processes of these compounds.

Treatment of relapsed or refractory chronic lymphocytic leukemia

BACKGROUND

Recent advances in the treatment of chronic lymphocytic leukemia (CLL) have moved beyond the traditional use of alkylating agents and purine analogs into regimens combining these two chemotherapy classes with monoclonal antibodies.

METHODS

This article reviews treatments options for patients with relapsed or refractory CLL.

RESULTS

Several studies have investigated novel agents in treating patients with 17p deletion, TP53 mutation, and fludarabine-refractory CLL, as well as patients with suboptimal response to intense treatment. These investigational agents include rituximab, alemtuzumab, ofatumumab, bendamustine, high-dose methylprednisolone, lenalidomide, lumiliximab, cyclin-dependent kinase inhibitors, small modular immunopharmaceuticals, Bcl-2 inhibitors, and histone deacetylase inhibitors. While these newer drugs and combination therapies have shown promise as treatment options for CLL, additional studies are needed to determine the immunosuppression, toxicities, and infections associated with their use.

CONCLUSIONS

Despite improvement in initial overall response rates, most patients relapse and require further treatment. CLL remains incurable with standard therapies due to development of disease refractoriness. As such, novel approaches such as those noted above warrant continued research to improve outcomes for patients with CLL.

NCI First International Workshop on the Biology, Prevention, and Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation: Report from the Committee on Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation

Relapse is a major cause of treatment failure after allogeneic hematopoietic stem cell transplantation (alloHSCT). Treatment options for relapse have been inadequate, and the majority of patients ultimately die of their disease. There is no standard approach to treating relapse after alloHSCT. Withdrawal of immune suppression and donor lymphocyte infusions are commonly used for all diseases; although these interventions are remarkably effective for relapsed chronic myelogenous leukemia, they have limited efficacy in other hematologic malignancies. Conventional and novel chemotherapy, monoclonal antibody therapy, targeted therapies, and second transplants have been utilized in a variety of relapsed diseases, but reports on these therapies are generally anecdotal and retrospective. As such, there is an immediate need for well-designed, disease-specific trials for treatment of relapse after alloHSCT. This report summarizes current treatment options under investigation for relapse after alloHSCT in a disease-specific manner. In addition, recommendations are provided for specific areas of research necessary in the treatment of relapse after alloHSCT.

Current and emerging treatments for chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) is the most common adult leukaemia in Europe and North America. The disease is characterized by proliferation and accumulation of small CD5+ B cells in blood, lymph nodes, spleen, liver and bone marrow. The natural clinical course of CLL is highly variable, and chemotherapy is usually not indicated in early and stable disease. However, patients with progressive and more advanced CLL require treatment. For many years, chlorambucil with or without corticosteroids was used in previously untreated patients with CLL. More recently, purine nucleoside analogues (PNAs) [fludarabine, cladribine and pentostatin] have been included in treatment approaches for this disease, and chlorambucil is no longer the leading standard everywhere. Currently, this drug is rather recommended for the treatment of older, unfit patients with co-morbidities, especially in European countries. Significantly higher overall response (OR) and complete response (CR) rates in patients treated initially with PNAs than in those treated with chlorambucil or cyclophosphamide-based combination regimens have been confirmed in randomized, prospective, multicentre trials. Moreover, PNAs administered in combination with cyclophosphamide produce higher response rates, including CR and molecular CR, compared with PNA as monotherapy. Recent reports suggest that the administration of monoclonal antibodies (mAbs) can significantly improve the course of CLL. At present, two mAbs have the most important clinical value in patients with CLL. The first is rituximab, a human mouse antibody that targets CD20 antigens, and the second is alemtuzumab, a humanized form of a rat antibody active against CD52. Several recent reports suggest that in patients with CLL, rituximab combined with a PNA can increase the OR and CR rates compared with PNA or rituximab alone, with acceptable toxicity. In randomized trials, the combination of rituximab with fludarabine and cyclophosphamide (FC-R regimen) demonstrated higher rates of OR, CR and progression-free survival in patients with previously untreated and relapsed or refractory CLL than fludarabine plus cyclophosphamide (FC regimen). Several reports have confirmed significant activity with alemtuzumab in relapsed or refractory CLL, as well as in previously untreated patients. Recently, several new agents have been investigated and have shown promise in treating patients with CLL. These treatments include new mAbs, agents targeting the antiapoptotic bcl-2 family of proteins and receptors involved in mediating survival signals from the microenvironment, antisense oligonucleotides and other agents. The most promising are new mAbs directed against the CD20 molecule, lumiliximab and anti-CD40 mAbs. Oblimersen, alvocidib (flavopiridol) and lenalidomide are also being evaluated both in preclinical studies and in early clinical trials. In recent years, a significant improvement in haematopoietic stem cell transplantation (HSCT) procedures in patients with high-risk CLL has been observed. However, the exact role of HSCT, autologous or allogeneic, in the standard management of CLL patients is still undefined.

Second neoplasms in chronic lymphocytic leukemia: incidence and pathogenesis with emphasis on the role of different therapies

Several surveys have defined chronic lymphocytic leukemia (CLL) patients as a high-risk patient population for developing second neoplasms. As possible mechanisms underlying the increased risk of specific second malignancies in CLL patients the immunodeficiency associated with disease is generally proposed. As far as secondary acute leukemia is concerned, greater insight into the molecular pathogenesis of therapy-related acute myeloid leukemia (AML) developing in CLL would allow to avoid treatment regimens that can lead to this complication. Richter's syndrome continues to be a fatal and highly refractory to chemotherapy disease complicating the clinical course of CLL. Therefore, experimental approaches of therapy should be considered in its treatment. Given the prolonged survival of patients with CLL, it is important to recognize early a second cancer especially whether new symptoms or physical findings arise.

Treatment of fludarabine-refractory chronic lymphocytic leukemia

The development of resistance to purine analogs defines a poor-risk subset of patients with chronic lymphocytic leukemia (CLL). Although in recent years chemoimmunotherapeutic combinations such as fludarabine, cyclophosphamide, and rituximab have induced response rates of 95% in previously untreated patients and increased the rates of failure-free survival, CLL remains incurable for many patients because of a lack of disease response or the development of refractoriness to fludarabine. Fludarabine-refractory disease is defined as CLL that does not respond to fludarabine or that recurs within 6 months of treatment with a fludarabine-containing regimen. The natural course of the disease is associated with poor survival. Salvage therapeutic strategies include alemtuzumab-containing regimens, targeted agents, and allogeneic stem cell transplantation. Single-agent alemtuzumab induces response in up to 40% of patients with fludarabine-refractory CLL, but responses are not durable, and the median survival is approximately 1 to 2 years. Alemtuzumab is also combined with fludarabine, cyclophosphamide, and/or rituximab, and other agents such as lenalidomide and flavopiridol, as well as targeted agents, and used in fludarabine-refractory CLL. Cumulative evidence suggests that allogeneic stem cell transplantation is an efficacious therapeutic strategy for patients who do not respond to fludarabine or who develop disease recurrence within 12 months after purine analog treatment. In conclusion, chemoimmunotherapy regimens that include alemtuzumab and/or rituximab and allogeneic stem cell transplantation improve the prognosis of this disease, but there is a continued need for novel, more effective therapies.

Characteristics associated with important clinical end points in patients with chronic lymphocytic leukemia at initial treatment

PURPOSE

Response to front-line treatment and subsequent clinical course for patients with chronic lymphocytic leukemia (CLL) are heterogeneous. Identifying pretreatment patient characteristics or prognostic factors associated with clinical outcomes is important for counseling patients, conducting clinical research, and evaluating trial results.

PATIENTS AND METHODS

We evaluated the pretreatment characteristics of 595 previously untreated patients who had National Cancer Institute Working Group indications to initiate front-line therapy for predictors of complete response (CR), time to treatment failure (TTF), and overall survival (OS). Multivariable models were developed for all three end points.

RESULTS

CR is an important treatment end point correlated with longer TTF and OS. In this retrospective analysis, front-line treatment regimen was a significant independent predictive factor for all three end points; chemoimmunotherapy was the superior treatment regimen. Considering front-line treatment regimen, other independent patient characteristics associated with CR included age and beta(2)-microglobulin (beta-2M). TTF was independently associated with age, beta-2M, percent lymphocytes in bone marrow, and treatment regimen. Improved OS was independently associated with younger age, lower beta-2M, and treatment regimen. Two weighted prognostic models or nomograms, one including and one excluding treatment regimen, were constructed using significant characteristics to predict 5- and 10-year survival probability and estimate median survival time.

CONCLUSION

Identifying pretreatment patient characteristics associated with CR, TTF, and OS establishes a baseline to compare and incorporate new prognostic factors. Treatment had an impact on the significance of these factors. Prognostic models may help patients and clinicians in decision making as well as facilitate clinical research through design and analyses of clinical trials.

Current status of older and new purine nucleoside analogues in the treatment of lymphoproliferative diseases

For the past few years more and more new cytotoxic agents active in the treatment of hematological malignancies have been synthesized and become available for either in vitro studies or clinical trials. Among them the class of antineoplastic drugs belonging to the purine nucleoside analogues group (PNAs) plays an important role. Three of them: pentostatin (DCF), cladribine (2-CdA) and fludarabine (FA) were approved by Food and Drug Administration (FDA) for the treatment of hematological malignancies. Recently three novel PNAs: clofarabine (CAFdA), nelarabine (ara-G) and forodesine (immucillin H, BCX-1777) have been synthesized and introduced into preclinical studies and clinical trials. These agents seem to be useful mainly for the treatment of human T-cell proliferative disorders and they are currently undergoing clinical trials in lymphoid malignancies. However, there are also several studies suggesting the role of these drugs in B-cell malignancies. This review will summarize current knowledge concerning the mechanism of action, pharmacologic properties, clinical activity and toxicity of PNAs accepted for use in clinical practice, as well as new agents available for clinical trials.

Fludarabine in the treatment of chronic lymphocytic leukemia: a review

Fludarabine (FAMP) is the most effective and most extensively studied purine analog in indolent B-cell malignancies. Its use is indicated for first-and second-line treatment of B-cell chronic lymphocytic leukemia (B-CLL). FAMP as a single agent has produced superior response rates and progression-free survival than standard therapy with chlorambucil and alkylator-based regimen. Efficacy of FAMP may be increased by combining this purine analog with other chemotherapeutic and non-chemotherapeutic agents. FAMP and cyclophosphamide combination (FC) has shown promising results with higher overall response and complete response rates than FAMP in monotherapy, although no difference has been detected in survival. Quality of response and eradication of minimal residual disease (MRD) have been reported to be associated with prolonged survival. Eradication of MRD has been achieved by combining FC with mitoxantrone or monoclonal antibody including alemtuzumab or rituximab or both. FAMP has been widely used in non-myeloablative conditioning regimens, often combined with a variety of other cytotoxic agents, with the aim of inducing enough immunosuppression to allow successful engraftment and to exert some pretransplant anti-tumor activity. The current paper provides an overview of use of FAMP as a single agent or as a cornerstone of different therapeutic strategies for treatment of B-CLL patients.

Other malignancies in chronic lymphocytic leukemia/small lymphocytic lymphoma

PURPOSE

Other malignancies have been reported to occur with increased frequency in chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). The aim of this study was to determine the frequency, outcomes, and factors associated with other cancers in patients with CLL/SLL.

PATIENTS AND METHODS

We reviewed the records of consecutive patients with previously untreated CLL/SLL seen at The University of Texas M. D. Anderson Cancer Center from 1985 to 2005. The number of second cancers observed was compared with the number expected from the Surveillance, Epidemiology, and End Results database.

RESULTS

Among 2,028 patients, 324 (16%) had a history of other cancers and 227 (11.2%) developed other malignancies during the follow-up period. Overall, 625 cancers were observed in 551 patients, including skin (30%), prostate (13%), breast (9%), melanoma (8%), lymphoma (8%), gastrointestinal (9%), lung (6%), and other cancers (17%). The risk of a second cancer was 2.2 times higher than the expected risk. The response rates in patients with and without a history of other cancers were 86% and 92%, respectively (P = .04), and the 5-year survival rates were 70% and 82%, respectively (P < .001). In Cox analysis, independent factors predicting development of new cancers were older age, male sex, and elevated levels of beta2-microglobulin, lactate dehydrogenase, and creatinine. In patients who were treated for CLL/SLL, the treatment regimen did not affect the risk of subsequent cancer (P = .49).

CONCLUSION

Patients with CLL/SLL have more than twice the risk of developing a second cancer and an increased frequency of certain cancer types. Awareness of risk factors could permit early detection.

Long-term results of the fludarabine, cyclophosphamide, and rituximab regimen as initial therapy of chronic lymphocytic leukemia

Early results of the fludarabine, cyclophosphamide, and rituximab (FCR) regimen in 224 patients showed that it was highly active as initial therapy of chronic lymphocytic leukemia. In this report, we present the final results of all 300 study patients at a median follow up of 6 years. The overall response rate was 95%, with complete remission in 72%, nodular partial remission in 10%, partial remission due to cytopenia in 7%, and partial remission due to residual disease in 6%. Two patients (< 1%) died within 3 months of starting therapy. Six-year overall and failure-free survival were 77% and 51%, respectively. Median time to progression was 80 months. Pretreatment characteristics independently associated with inferior response were age 70 years or older, beta2-microglobulin twice the upper limit of normal (2N) or more, white cell count 150 x 10(9)/L or more, abnormal chromosome 17, and lactate dehydrogenase 2N or more. No pretreatment characteristic was independently associated with decreased complete remission duration. The risk of late infection was 10% and 4% for the first and second years of remission, respectively, and less than 1.5% per year for the third year onward. In a multivariate analysis of patients receiving fludarabine-based therapy at our center, FCR therapy emerged as the strongest independent determinant of survival.

Liposomal Coencapsulated Fludarabine and Mitoxantrone for Lymphoproliferative Disorder Treatment**Xiaobin Zhao and Jianmei Wu contributed equally to this study

Fludarabine (FLU)-based combination therapies are commonly used to treat low-grade lymphoma and chronic lymphocytic leukemia (CLL) patients. In vitro and clinical studies have indicated advantages when FLU and mitoxantrone (MTO) are applied in combination. To further enhance this effect, these two agents were coencapsulated in liposomes. FLU was passively encapsulated during liposome formation, and MTO was loaded with a transmembrane pH gradient. Entrapment efficiency, particle size, stability, and drug release kinetics were characterized. In vitro cytotoxicity study was carried out in two representative B-cell lines: Wac3CD5 and Raji. Synergism as measured by combination index (CI) was observed in cells treated with liposomes coencapsulating FLU and MTO. Annexin V/propidium iodide (PI) analysis further confirmed that coencapsulated FLU and MTO improved the percentage of apoptosis among primary CLL cells. These data suggest that adopting liposomes containing coencapsulated drug combinations constitutes a potential strategy to promote drug synergism and may have utility in the treatment of leukemia and lymphoma.

Chemoimmunotherapy of chronic lymphocytic leukemia

The past two decades have seen a major paradigm shift in the therapy of chronic lymphocytic leukemia (CLL), with the treatment goal shifting from symptom palliation to the attainment of maximal disease control using the most effective frontline regimens available, thus prolonging survival and possibly leading to cure. The most potent therapeutic regimens developed to date include the chemoimmunotherapy combinations incorporating purine analogs and monoclonal antibodies. We review the evolution of modern chemoimmunotherapy for CLL, and discuss current research directions for further refining the potency of these regimens.

Assessment of chronic lymphocytic leukemia and small lymphocytic lymphoma by absolute lymphocyte counts in 2,126 patients: 20 years of experience at the University of Texas M.D. Anderson Cancer Center

PURPOSE

Chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) are currently considered the same entity, but controversy remains over whether CLL and SLL should be treated similarly. We assessed whether characteristics of patients with CLL and SLL differ in ways other than the absolute lymphocyte count (ALC) and evaluated treatment outcomes and prognostic factors.

METHODS

We searched the electronic database for patients with CLL or SLL who presented to The University of Texas M.D. Anderson Cancer Center (Houston, TX) between 1985 and 2005. We reviewed patient records to determine presenting characteristics, treatment, and clinical outcomes. Cox models using training and validation sets of patients and resampling methods were used to develop a model predicting survival.

RESULTS

Among 2,126 consecutive CLL/SLL patients, 312 (15%) had ALC less than 5 x 10(9)/L. Patients with ALC less than 5 x 10(9)/L had lower rates of cytogenetic abnormalities (P = .0002) and higher rates of CD38-positive results (P = .0002) and had mutated immunoglobulin heavy-chain variable region gene status (P = .034). Rates of response, survival, and failure-free survival (FFS) were not different among ALC groups. Regimens that included rituximab and a nucleoside analog were associated with superior rates of response and FFS compared with other therapies, irrespective of ALC. Deletion 17p or 6q with or without other cytogenetic abnormalities, age at least 60 years, beta2-microglobulin at least 2 mg/L, albumin less than 3.5 g/dL, and creatinine at least 1.6 mg/dL were each found to independently predict shorter survival and formed the basis of a scoring system.

CONCLUSION

Patients with CLL or SLL can be treated similarly. A new prognostic score is proposed.

Recent progress in the management of chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a clonal disease characterized by proliferation and accumulation of small CD5-positive B cells. More than 50% of patients are asymptomatic at diagnosis and usually require no treatment. However, treatment is needed in the advanced and progressive disease. Chlorambucil with or without steroids has been the drug of choice for many years in previously untreated patients with CLL. The purine nucleoside analogs (PNAs), fludarabine (FA), cladribine (2-CdA-chlorodeoxyadenosine) and pentostatin (DCF, 2'-deoxycoformycin) also have been introduced for treatment of CLL. Significantly higher overall response (OR) and complete response (CR) and longer progression free survival (PFS) in patients with CLL treated with FA or 2-CdA have been confirmed in randomized, multicenter trials and more recently in meta-analysis. However, the median survival time did not differ between patients treated with PNA and alkylating agents. Combination therapies with PNAs and cyclophosphamide and especially with cyclophosphamide and rituximab are more active than monotherapy in terms of OR, CR and PFS. Several reports have shown significant activity of alemtuzumab in previously untreated and pretreated patients even when refractory to FA. Alemtuzumab also can be used in CLL as a preparative regimen before stem cell transplantation (SCT) and to eliminate minimal residual disease (MRD). Recently, several new agents have shown promise in treating CLL, including new monoclonal antibodies, agents targeting bcl-2 family of proteins, antisense oligonucleotides and other agents. Moreover, autologous and allogenic hematopoietic cell transplantations are increasingly considered for treatment of patients with CLL. In this review current therapeutic strategies in CLL are presented.

Correlation of ZAP-70 expression in B cell leukemias to the ex vivo response to a combination of fludarabine/genistein

The role of ZAP-70 expression on the ex vivo response of blood cells from CLL and PLL patients to a combination of fludarabine, a purine analog, and genistein, a tyrosine kinase inhibitor was studied. Patient cells were studied for the expression of ZAP-70 mRNA and its relation to the induction of apoptosis in response to treatment with genistein 15-60 muM and/or fludarabine 3 muM. The combination of genistein and fludarabine resulted in a significantly increased induction of apoptosis relative to the fludarabine alone. The ex vivo patient cells with a high ZAP-70 expression underwent more apoptosis in response to genistein than did patient cells with a low ZAP-70 mRNA expression. In contrast, basal IL-10 mRNA expression correlated negatively with apoptosis induction in response to genistein (P < 0.01). These studies suggest that, in malignant B cells that express elevated levels of the ZAP-70 signaling molecule, genistein may inhibit the ZAP-70 tyrosine kinase activity, resulting in cell death. The ZAP-70 may serve as a target for therapy. In addition, these studies suggest that the IL-10 expression by malignant B cells may not only suppress anti-tumor T cell responses in vivo, but also promote the survival of malignant B cells despite treatment with chemotherapeutic agents.

Fludarabine in chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) is the most common leukaemia in the Western world. Historically, CLL patients have received prednisone- or chlorambucil-containing regimens, resulting in modest responses and a slim chance of long-term survival. The addition of purine nucleoside analogues, specifically fludarabine, to the armamentarium has significantly improved efficacy in treatment-naive or heavily pretreated CLL patients. Since the 1980s, fludarabine monotherapy has demonstrated an improvement in response over historical chemotherapeutic agents. Single-agent fludarabine therapy has expanded into a combination regimen containing cyclophosphamide and has further evolved to incorporate monoclonal antibodies. A review of the fludarabine literature shows that these advancements in fludarabine-containing therapy have enhanced the overall patient response with a potential increase in survival time, thus representing progress towards a superior treatment for CLL.

Chronic lymphocytic leukemia: diagnosis and treatment

Traditionally, the goal of therapy in chronic lymphocytic leukemia (CLL) has been palliative, with first-line therapy using alkylating agents and/or involved field radiotherapy (depending on the stage of disease and sites of involvement) because of the older age of affected patients and the low rate of complete remissions (CRs) with no improvement in overall survival despite treatment. With increasing knowledge about the biology, molecular genetics, and prognostic factors of the disease, the philosophy of care for patients with CLL has evolved from palliation to aiming for a potential cure, especially in younger patients. Furthermore, multiple treatment options have emerged, including purine analogues, monoclonal antibodies, and potentially stem cell transplantation. These have been associated with higher frequencies of CRs and longer durations of responses compared to conventional chemotherapy. In addition, a subset of patients treated with chemoimmunotherapy can achieve durable CRs and molecular remissions. This may translate into improved disease-free survival and potentially a "cure." Because of the heterogeneous nature of CLL, new prognostic markers are currently being incorporated into clinical trials to determine their role in routine clinical practice. This review summarizes current therapeutic regimens that are being evaluated in patients with CLL and management of disease-related complications.

Bioreductive activation of mitoxantrone by NADPH cytochrome P450 reductase. Implications for increasing its ability to inhibit the growth of sensitive and multidrug resistant leukaemia HL60 cells

The aim of this study was to examine the role of reductive activation of mitoxantrone (MX) by human liver NADPH cytochrome P450 reductase (CPR) in increasing its ability to inhibit the growth of human promyelocytic sensitive leukaemia HL60 cell line as well as its MDR sublines exhibiting two different phenotypes of MDR related to the overexpression of P-glycoprotein (HL60/VINC) or MRP1 (HL60/DOX). Our assays showed that the reduction of MX by exogenously added CPR in the presence of low NADPH concentration had no effect in increasing its ability to inhibit the growth of sensitive and MDR tumour cells. In contrast, an important increase in antiproliferative activity of MX after its reductive activation by CPR at high NADPH concentration was observed against HL60/VINC as well as HL60/DOX cells.

The influence of increasing age on the deliverability and toxicity of fludarabine-based combination chemotherapy regimens in patients with indolent lymphoproliferative disorders

BACKGROUND

Fludarabine-based combination chemotherapy regimens are highly effective in the treatment of patients with indolent lymphoproliferative disorders. Despite the prevalence of such disorders in older patients, the effect of increasing age on the deliverability of these regimes has not been assessed.

METHODS

The authors analyzed the effect of increasing age on the deliverability and toxicity of 3 fludarabine-based regimens, all using fludarabine 25 mg/m2 per day for 3 days intravenously every 28 days, in 180 patients who were stratified into 2 age groups (age <60 years and age > or =60 years), with multivariate analysis to control for other differences between groups. The authors also explored the impact of age > or =70 years within the older cohort.

RESULTS

Older patients were more likely to experience an episode of nonsevere hematologic or infectious toxicity, but there was no difference in the rate of severe toxicity. Toxicity rates per cycle did not differ between age groups. The rates of neutropenia (absolute neutrophil count [ANC], < 1.0 x 10(9)/L) and severe neutropenia (ANC, 0.5 x 10(9)/L) were 22% and 13%, respectively, in older patients versus 20% and 11%, respectively, in younger patients (P > .1 for both). The rates of thrombocytopenia (platelet count, <100 x 10(9)/L) and severe thrombocytopenia (platelet count, <50 x 10(9)/L) were 21% and 5%, respectively, in older patients and 16% and 5%, respectively, in younger patients (each P value > .1). The rate of infection was 18% per cycle in older patients and 15% per cycle in younger patients (P = .2), with no difference noted in severity. Other organ toxicities were uncommon and showed no difference between age groups. The treatment-related mortality rate was <1% in both cohorts (P > .5). In multivariate analysis, increasing age and performance status influenced the incidence of hematologic toxicity, whereas only performance status influenced the rate of infection and severe infection.

CONCLUSIONS

Fludarabine-based combination chemotherapy regimens were well tolerated and can be delivered safely to older patients who have a good performance status with modestly increased myelosuppression but no increase in severe infectious complications or treatment-related mortality.

Fludarabine in Combination With Alemtuzumab Is Effective and Feasible in Patients With Relapsed or Refractory B-Cell Chronic Lymphocytic Leukemia: Results of a Phase II Trial

Purpose

To determine the efficacy and safety of a newly developed concomitant administration of fludarabine and alemtuzumab (FluCam) in patients with relapsed or refractory B-cell chronic lymphocytic leukemia (B-CLL).

Patients and Methods

A total of 36 patients were treated in this phase II study (median age, 61.47 years; mean number of prior chemotherapies, 2.6; Binet stage C, n = 28). After an initial dose escalation of alemtuzumab over 3 days, alemtuzumab 30 mg and fludarabine 30 mg/m2 were administered on 3 consecutive days. Treatment was repeated after 28 days for up to six cycles. Restaging (following National Cancer Institute criteria) was carried out after cycles 2 and 4 and 1 month after the end of treatment.

Results

The overall response rate was 83% (11 complete responses, 19 partial responses, one stable disease, and five progressive diseases). Two patients with progressive disease developed fungal pneumonias, and one patient died as a result of Escherichia coli sepsis. Two subclinical cytomegalovirus reactivations occurred.

Conclusion

The new FluCam regimen is effective and feasible in patients with relapsed and refractory B-CLL.

Cytogenetic testing for therapeutic indication in cancer

The association of cytogenetic abnormalities with cancer is well established. However, due to the historic lack of specific insight into the functional role of these anomalies, they have mostly served as diagnostic and/or prognostic indicators. Recent developments in chronic myelogenous leukemia and breast cancer have raised hopes for specific cytogenetic alterations to serve as therapeutic targets. This article reviews the aid provided by molecular diagnostics in these exciting developments in the cancer arena.

Immunosuppression and infectious complications in patients with stage IV indolent lymphoma treated with a fludarabine, mitoxantrone, and dexamethasone regimen

BACKGROUND

Myelosuppression and immunosuppression occur with purine analogs. The objective of the current study was to investigate the effects of combined fludarabine, mitoxantrone, and dexamethasone (FND) followed by interferon/dexamethasone on myelosuppression (absolute neutrophil counts), immunosuppression (CD4 and CD8 counts), and infectious complications in patients with previously untreated, Stage IV indolent lymphoma.

METHODS

Seventy-three patients were treated. All patients received Pneumocystis carinii pneumonia (PCP) prophylaxis. CD4 and CD8 counts, serum immunoglobulin (Ig) levels, and neutrophil counts were correlated with infectious complications.

RESULTS

The median follow-up was 6.1 years. Sixty of 73 patients had CD4, CD8, or Ig measurements. The median baseline CD4 count was 764/microL. This CD4 level decreased to 238/microL at 1 year and to 264/microL at 2 years; and it rose to 431/microL by 3 years and to 650/microL at 4 years. CD8 counts did not change significantly. The median baseline serum IgG level was 989 mg/d, decreased to 536 mg/dL at 1 year and to 693 mg/dL at 2 years, and it rose to 949 mg/dL at 3 years and to 1080 mg/dL at 4 years. Fourteen patients (19%) developed Grade 3-4 infections, the majority during FND therapy with neutropenia and/or accompanied by CD4 counts < 200/microL. CD4, CD8, and neutrophil counts did not differ between patients who developed Grade 3-4 infections, Grade 1-2 infections, or no infections.

CONCLUSIONS

Most infections with FND occurred during FND, in the setting of neutropenia, often with concurrent low CD4 counts. The overall safety profile for FND was good. However, patients should be monitored for opportunistic infections, and prophylactic antibiotics are recommended, particularly against PCP.

A new model for predicting infectious complications during fludarabine-based combination chemotherapy among patients with indolent lymphoid malignancies

BACKGROUND

Fludarabine-containing combination chemotherapy regimens are increasingly used in the treatment of indolent lymphoid malignancies, with the associated risk of infection being the major toxicity. Predictors of infection during fludarabine-containing combination therapy are poorly defined and optimal strategies for infection prophylaxis are not known. The authors analyzed their experience with patients treated with the fludarabine-mitoxantrone (FM) or fludarabine-cyclophosphamide (FC) regimens to develop a predictive model for infections.

METHODS

Ninety-two patients with indolent lymphoid malignancies were treated with FM (n = 29) or FC (n = 63). Baseline variables including age, gender, regimen, disease histology, previous therapy, time from diagnosis to current treatment, performance status, renal function, absolute neutrophil count (ANC), lymphocyte count, and immunoglobulin G levels were examined retrospectively for their association with risk of infectious complications during or within 4 weeks of therapy.

RESULTS

Six risk factors were associated with infectious complications: age > 60 years, > or = 3 previous therapies, previous fludarabine exposure, time from diagnosis to current treatment of > 3 years, performance status > or = 2, and baseline ANC < 2.0 x 10(9)/L. Compared with patients with 0-2 risk factors, patients with > or = 3 risk factors had higher infection rates (26% vs. 7% per cycle, P < 0.0001), more Grade 4 neutropenia (41% vs. 8% per cycle, P < 0.0001), and more neutropenic sepsis (15% vs. 1% per cycle, P < 0.0001).

CONCLUSIONS

Infection risk during fludarabine-containing combination chemotherapy was predicted with a model comprising six baseline risk factors. Patients predicted to be at high risk of infection were an appropriate group for consideration of prophylactic strategies.