The frequency, manifestations, and duration of prolonged cytopenias after first-line fludarabine combination chemotherapy

Enhancing cellular immunotherapies in cancer by engineering selective therapeutic resistance

Adoptive cell therapies engineered to express chimeric antigen receptors (CARs) or transgenic T cell receptors (TCRs) to recognize and eliminate cancer cells have emerged as a promising approach for achieving long-term remissions in patients with cancer. To be effective, the engineered cells must persist at therapeutically relevant levels while avoiding off-tumour toxicities, which has been challenging to realize outside of B cell and plasma cell malignancies. This Review discusses concepts to enhance the efficacy, safety and accessibility of cellular immunotherapies by endowing cells with selective resistance to small-molecule drugs or antibody-based therapies to facilitate combination therapies with substances that would otherwise interfere with the functionality of the effector cells. We further explore the utility of engineering healthy haematopoietic stem cells to confer resistance to antigen-directed immunotherapies and small-molecule targeted therapies to expand the therapeutic index of said targeted anticancer agents as well as to facilitate in vivo selection of gene-edited haematopoietic stem cells for non-malignant applications. Lastly, we discuss approaches to evade immune rejection, which may be required in the setting of allogeneic cell therapies. Increasing confidence in the tools and outcomes of genetically modified cell therapy now paves the way for rational combinations that will open new therapeutic horizons.

Chimeric Antigen Receptor T-Cell Therapy and Hematopoiesis

Chimeric Antigen Receptor (CAR) T-cell therapy is a promising treatment option for patients suffering from B-cell- and plasma cell-derived hematologic malignancies and is being adapted for the treatment of solid cancers. However, CAR T is associated with frequently severe toxicities such as cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), macrophage activation syndrome (MAS), and prolonged cytopenias-a reduction in the number of mature blood cells of one or more lineage. Although we understand some drivers of these toxicities, their mechanisms remain under investigation. Since the CAR T regimen is a complex, multi-step process with frequent adverse events, ways to improve the benefit-to-risk ratio are needed. In this review, we discuss a variety of potential solutions being investigated to address the limitations of CAR T. First, we discuss the incidence and characteristics of CAR T-related cytopenias and their association with reduced CAR T-cell efficacy. We review approaches to managing or mitigating cytopenias during the CAR T regimen-including the use of growth factors, allogeneic rescue, autologous hematopoietic stem cell infusion, and alternative conditioning regimens. Finally, we introduce novel methods to improve CAR T-cell-infusion products and the implications of CAR T and clonal hematopoiesis.

Infectious complications after intensive chemotherapy with CLAG-M versus 7+3 for AML and other high-grade myeloid neoplasms

Contemporary data on infections after intensive chemotherapy for acute myeloid leukemia (AML) are scarce. Cladribine, high-dose cytarabine, G-CSF, and dose-escalated mitoxantrone ("CLAG-M") may result in higher remission rates than standard-dose cytarabine plus anthracycline ("7 + 3") but may result in more infections. We compared moderate to severe infections occurring up to 90 days after the first induction cycle for AML or other high-grade myeloid neoplasms in patients receiving CLAG-M for newly diagnosed (n = 196) or relapsed/refractory disease (n = 131) or 7 + 3 for newly diagnosed disease (n = 115). For newly diagnosed disease, microbiologically documented infections were more frequent after CLAG-M compared to 7 + 3 (adjusted rate ratio, 1.65 [95% CI, 1.06-2.58]; P = 0.03), with a cumulative incidence of 27.8% and 16.5% by day 90, respectively. Patients receiving CLAG-M for relapsed/refractory disease had the highest cumulative incidence of 50.7%. Bacterial bloodstream infections were the most frequent followed by respiratory tract infections. Among 29 patients (7%) who died, infection was a primary or contributing cause of death in 59%. These data indicate that infections continue to cause substantial morbidity in patients treated for AML, especially those treated for relapsed/refractory disease, and are more common with newer, more myelosuppressive regimens such as CLAG-M. Improved strategies for infection prevention are needed.

Managing Waldenström's macroglobulinemia with BTK inhibitors

Bruton's tyrosine kinase (BTK) inhibition is one of the treatment standards for patients with relapsed/refractory Waldenström's macroglobulinemia (WM) and for patients with WM who are unsuitable for immunochemotherapy (ICT). It offers deep and durable responses with a manageable safety profile that is generally favorable compared with ICT regimens. However, the limitations of the first approved BTK inhibitor (BTKi), ibrutinib, include reduced efficacy in patients lacking the characteristic WM mutation (MYD88L265P) and toxicities related to off-target activity. The risk of atrial fibrillation (AF) and other cardiovascular side effects are a notable feature of ibrutinib therapy. Several next-generation covalent BTKis with greater selectivity for BTK are at various stages of development. In November 2021, zanubrutinib became the first of these agents to be approved by the European Medicines Agency for the treatment of WM. Head-to-head trial data indicate that it has comparable efficacy to ibrutinib for patients with WM overall, although it may be more effective in patients with CXCR4 mutations or wild-type MYD88. In the clinical trial setting, its greater selectivity translates into a reduced risk of cardiovascular side effects, including AF. Acalabrutinib, which is pre-approval in WM, appears to offer similar advantages over ibrutinib in terms of its safety profile. Beyond the next-generation covalent BTKis, non-covalent BTKis are an emerging class with the potential to provide a therapeutic option for patients who relapse on covalent BTKis. In the future, BTKis may be increasingly utilized within combination regimens. Several ongoing trials in WM are investigating the potential for BTKi use in combination with established and novel targeted agents.

Safety and Efficacy of Bendamustine and Rituximab (BR) Regimen in Indian Chronic Lymphocytic Leukaemia Patients

We investigated the safety and efficacy of bendamustine-rituximab (BR) in previously untreated symptomatic and advanced CLL patients, as there is no data available on BR from the Indian subcontinent.This retrospective study included 120 consecutive treatment naïve patients with CLL without del (17p), who were registered at the Department of Medical Oncology, AIIMS between January 2010 and July 2018. Bendamustine was given at a dose of 90 mg/m2 on days 1 and 2, combined with rituximab 375 mg/m2 rituximab on day 1, every 28 days for up to 6 courses. Event-free survival (EFS) was defined as the date of treatment to date of relapse, disease progression, or death due to any cause.The median age was 57 years (range: 30-75 years). As per the clinical Rai stage, 30 (25%) patients were in stage II, 42 (35%) were in stage III and 48 (40%) were in stage IV. ZAP70 was positive (> 20%) in 50%, CD 38 was positive (> 30%) in 33%, and CD49d was positive (> 30%) in 49% of cases. Beta-2 microglobulin (B2M) was elevated (≥ 3.5 mg/L) in 80% of cases. Fifty-five cases (50%, n = 110) were IGHV mutated. The mean number of cycles was 5 (1-6). The overall response rate (ORR) seen with BR was 90% and complete response was 45%. Median progression-free survival was 24 months with a median follow-up period of 29 months. Haemoglobin (< 10 g/dL), elevated B2 M, unmutated IGHV had a statistically significant adverse impact on EFS on univariate analysis but on multivariate analysis, only IGHV mutation status was found to had significance on EFS. The median EFS was 27 months in IGHV mutated versus 18 months in IGHV unmutated-CLL patients (p = 0.001). Grade 3/4 neutropenia, thrombocytopenia, anemia, and infections were observed in 30.6%, 8%, and 12% respectively. The most common non-hematological toxicity was skin rash which was grade 1/2 in 24 (20%) cases and grade 3/4 in 12 (10%) cases. This is the largest study from India to demonstrate the safety and efficacy of BR in symptomatic CLL patients. BR is an effective and safe regimen in the first-line treatment of CLL. Unmutated-CLL patients have inferior EFS than mutated-CLL patients. Skin toxicity was the most common adverse effect seen in our population which was observed in around one-third of cases.

Solute Carrier Nucleoside Transporters in Hematopoiesis and Hematological Drug Toxicities: A Perspective

Simple Summary

Anticancer nucleoside analogs are promising treatments that often result in damaging toxicities and therefore ineffective treatment. Mechanisms of this are not well-researched, but cellular nucleoside transport research in mice might provide additional insight given transport’s role in mammalian hematopoiesis. Cellular nucleoside transport is a notable component of mammalian hematopoiesis due to how mutations within it relate to hematological abnormities. This review encompasses nucleoside transporters, focusing on their inherent properties, hematopoietic role, and their interplay in nucleoside drug treatment side effects. We then propose potential mechanisms to explain nucleoside transport involvement in blood disorders. Finally, we point out and advocate for future research areas that would improve therapeutic outcomes for patients taking nucleoside analog therapies.

Abstract

Anticancer nucleoside analogs produce adverse, and at times, dose-limiting hematological toxicities that can compromise treatment efficacy, yet the mechanisms of such toxicities are poorly understood. Recently, cellular nucleoside transport has been implicated in normal blood cell formation with studies from nucleoside transporter-deficient mice providing additional insights into the regulation of mammalian hematopoiesis. Furthermore, several idiopathic human genetic disorders have revealed nucleoside transport as an important component of mammalian hematopoiesis because mutations in individual nucleoside transporter genes are linked to various hematological abnormalities, including anemia. Here, we review recent developments in nucleoside transporters, including their transport characteristics, their role in the regulation of hematopoiesis, and their potential involvement in the occurrence of adverse hematological side effects due to nucleoside drug treatment. Furthermore, we discuss the putative mechanisms by which aberrant nucleoside transport may contribute to hematological abnormalities and identify the knowledge gaps where future research may positively impact treatment outcomes for patients undergoing various nucleoside analog therapies.

Pooled safety analysis of tisagenlecleucel in children and young adults with B cell acute lymphoblastic leukemia

BACKGROUND

Tisagenlecleucel, an anti-CD19 chimeric antigen receptor T cell therapy, has demonstrated efficacy in children and young adults with relapsed/refractory B cell acute lymphoblastic leukemia (B-ALL) in two multicenter phase 2 trials (ClinicalTrials.gov, NCT02435849 (ELIANA) and NCT02228096 (ENSIGN)), leading to commercialization of tisagenlecleucel for the treatment of patients up to age 25 years with B-ALL that is refractory or in second or greater relapse.

METHODS

A pooled analysis of 137 patients from these trials (ELIANA: n=79; ENSIGN: n=58) was performed to provide a comprehensive safety profile for tisagenlecleucel.

RESULTS

Grade 3/4 tisagenlecleucel-related adverse events (AEs) were reported in 77% of patients. Specific AEs of interest that occurred ≤8 weeks postinfusion included cytokine-release syndrome (CRS; 79% (grade 4: 22%)), infections (42%; grade 3/4: 19%), prolonged (not resolved by day 28) cytopenias (40%; grade 3/4: 34%), neurologic events (36%; grade 3: 10%; no grade 4 events), and tumor lysis syndrome (4%; all grade 3). Treatment for CRS included tocilizumab (40%) and corticosteroids (23%). The frequency of neurologic events increased with CRS severity (p<0.001). Median time to resolution of grade 3/4 cytopenias to grade ≤2 was 2.0 (95% CI 1.87 to 2.23) months for neutropenia, 2.4 (95% CI 1.97 to 3.68) months for lymphopenia, 2.0 (95% CI 1.87 to 2.27) months for leukopenia, 1.9 (95% CI 1.74 to 2.10) months for thrombocytopenia, and 1.0 (95% CI 0.95 to 1.87) month for anemia. All patients who achieved complete remission (CR)/CR with incomplete hematologic recovery experienced B cell aplasia; however, as nearly all responders also received immunoglobulin replacement, few grade 3/4 infections occurred >1 year postinfusion.

CONCLUSIONS

This pooled analysis provides a detailed safety profile for tisagenlecleucel during the course of clinical trials, and AE management guidance, with a longer follow-up duration compared with previous reports.

Prolonged hematologic toxicity following treatment with chimeric antigen receptor T cells in patients with hematologic malignancies

Chimeric antigen receptor T-cell therapy (CAR T) is a novel intervention for relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL) and other hematologic malignancies. However, it is associated with prolonged hematologic toxicity (PHT) that is unpredictable and can significantly impair patients' quality of life. Reported here is a single-center experience with PHT in adult patients with R/R DLBCL who received commercial CAR T-cell therapy between March 1, 2018 and May 30, 2020. Prolonged hematologic toxicity was defined as ≥ grade 3 neutropenia or thrombocytopenia at day +30 after CAR T-cell therapy. Of the 31 patients identified, 18 patients (58%) developed PHT. Patients with PHT had a shorter 1-year overall survival (OS) than patients without PHT (36% vs. 81%, P < .05). There were no differences in the median time to ANC recovery for those with PHT compared to patients without PHT (16 days vs. 15 days). Several risk factors were identified to be associated with PHT including CRS (P = .002), receipt of tocilizumab (P = .002) or steroids (P = .033), peak ferritin >5000 ng/ml (P = .048), peak C-reactive protein (CRP) > 100 mg/L (P = .007), and ferritin greater than the upper limit of normal at day +30. Seven patients with PHT underwent a bone marrow biopsy after CAR T-cell therapy; all showed complete aplasia or were hypocellular with cellularity ranging from <5% to 10%. These findings identify PHT as a significant toxicity associated with CAR T-cell therapy and highlight the critical need for further investigations to describe PHT in larger cohorts and identify standards for management of this condition.

Is There a Role for Chemotherapy in the Era of Targeted Therapies?

PURPOSE OF REVIEW

The treatment landscape of chronic lymphocytic leukemia has been rapidly evolving over the past few years. The prior standard of care, chemoimmunotherapy, is being replaced by targeted agents, and the utility of chemotherapy has come under question. In this review, we examine recent data comparing chemoimmunotherapy to targeted agents, how these data impact clinical management, and whether there are potential future roles for cytotoxic chemotherapy.

RECENT FINDINGS

Clinical trials have shown improved clinical outcomes with targeted agents compared to traditional chemoimmunotherapy. Based on these data, the current treatment paradigm primarily favors targeted agents over chemoimmunotherapy, with a few exceptions. However, targeted agents have notable limitations, and thus, there may be a future role of cytotoxic chemotherapy when administered in combination with targeted agents. Although targeted agents have nearly replaced chemoimmunotherapy in the treatment of chronic lymphocytic leukemia, novel combinations utilizing chemotherapy are being developed that may lead to better outcomes.

The UK NCRI study of chlorambucil, mitoxantrone and dexamethasone (CMD) versus fludarabine, mitoxantrone and dexamethasone (FMD) for untreated advanced stage follicular lymphoma: molecular response strongly predicts prolonged overall survival

We present a long-term follow-up of the UK chlorambucil, mitoxantrone and dexamethasone (CMD) versus fludarabine, mitoxantrone and dexamethasone (FMD) for untreated advanced, symptomatic follicular lymphoma (FL). This trial was the first to prospectively assess molecular response and the impact on outcomes for 400 patients. The median progression-free survival (PFS) and overall survival (OS) for CMD were 3·6 and 14·6 years vs. 3·0 and 15·7 years for FMD, respectively. Estimates for Restricted Mean Survival Time (RMST) suggested no difference in PFS or OS. For the whole cohort there was a highly significant difference in survival by POD24, with a median OS from a risk-defining event of 3·9 years compared to 13·7 years for all others (RMST P < 0·001). Molecular remission was achieved in 25/46 patients (54·3%) in the CMD arm and 20/41 (48·8%) in the FMD arm (P = 0·6). Molecular negativity resulted in median PFS of 5·6 years vs. 2·3 years for molecularly positive (log-rank P < 0·001) and median OS not reached versus 12·5 years (log-rank P < 0·01). No cases of progression occurred in minimal residual disease (MRD) negative patients after six years of follow-up. Although there was no difference in outcomes between arms, this is the first prospective study to report MRD negativity resulting in significantly improved OS.

Febrile Neutropenia in Acute Leukemia. Epidemiology, Etiology, Pathophysiology and Treatment

Acute leukemias are a group of aggressive malignant diseases associated with a high degree of morbidity and mortality. An important cause of both the latter is infectious complications. Patients with acute leukemia are highly susceptible to infectious diseases due to factors related to the disease itself, factors attributed to treatment, and specific individual risk factors in each patient. Patients with chemotherapy-induced neutropenia are at particularly high risk, and microbiological agents include viral, bacterial, and fungal agents. The etiology is often unknown in infectious complications, although adequate patient evaluation and sampling have diagnostic, prognostic and treatment-related consequences. Bacterial infections include a wide range of potential microbes, both Gram-negative and Gram-positive species, while fungal infections include both mold and yeast. A recurring problem is increasing resistance to antimicrobial agents, and in particular, this applies to extended-spectrum beta-lactamase resistance (ESBL), Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE) and even carbapenemase-producing Enterobacteriaceae (CPE). International guidelines for the treatment of sepsis in leukemia patients include the use of broad-spectrum Pseudomonas-acting antibiotics. However, one should implant the knowledge of local microbiological epidemiology and resistance conditions in treatment decisions. In this review, we discuss infectious diseases in acute leukemia with a major focus on febrile neutropenia and sepsis, and we problematize the diagnostic, prognostic, and therapeutic aspects of infectious complications in this patient group. Meticulously and thorough clinical and radiological examination combined with adequate microbiology samples are cornerstones of the examination. Diagnostic and prognostic evaluation includes patient review according to the multinational association for supportive care in cancer (MASCC) and sequential organ failure assessment (SOFA) scoring system. Antimicrobial treatments for important etiological agents are presented. The main challenge for reducing the spread of resistant microbes is to avoid unnecessary antibiotic treatment, but without giving to narrow treatment to the febrile neutropenic patient that reduce the prognosis.

Long-term follow-up of the RESONATE phase 3 trial of ibrutinib vs ofatumumab

Ibrutinib, a once-daily oral inhibitor of Bruton tyrosine kinase, has greatly improved outcomes for patients with chronic lymphocytic leukemia (CLL). The phase 3 RESONATE trial, which compared single-agent ibrutinib to ofatumumab in high-risk, relapsed patients with CLL, provided support for approval of ibrutinib in the United States and Europe. We describe long-term follow-up of patients treated in RESONATE, where continued superiority of progression-free survival (PFS) (hazard ratio [HR], 0.133; 95% confidence interval [CI], 0.099-0.178) was observed. Overall survival benefit continues (HR, 0.591; 95% CI, 0.378-0.926), although with decreased magnitude relative to that seen before crossover to ibrutinib was implemented for patients on ofatumumab (HR, 0.426; 95% CI, 0.220-0.823). Notably, overall response to ibrutinib increased over time, with 91% of patients attaining a response. The PFS benefit with ibrutinib was independent of baseline risk factors, although patients with ≥2 prior therapies had shorter PFS than those with <2 prior therapies, and the presence of TP53 or SF3B1 mutations showed a trend toward shorter PFS vs without these factors. Median duration of ibrutinib was 41 months, with 46% remaining on treatment at a median follow-up of 44 months. Grade ≥3 adverse events generally decreased over time, causing only a small proportion of patients to cease therapy. Ibrutinib was discontinued due to progressive disease in 27% of patients. This long-term study provides support for sustained efficacy and safety of ibrutinib in relapsed/refractory CLL and consideration of study provisions that allow crossover to investigational therapy when benefit has been clearly demonstrated. This trial was registered at www.clinicaltrials.gov as #NCT01578707.

Persistently low lymphocyte counts after FCR therapy for chronic lymphocytic leukemia are associated with longer overall survival

Decreased absolute lymphocyte counts (ALCs) following frontline therapy for chronic lymphocytic leukemia may be associated with disease control, even in patients without evidence of minimal residual disease. We studied the prognostic significance of ALCs during the first year following treatment with fludarabine, cyclophosphamide, and rituximab (FCR). We evaluated 99 patients who achieved a partial response without lymphocytosis (<4.0 × 10³ cells/μL) or better after FCR. Absolute lymphocyte counts were recorded at 3-, 6-, 9-, and 12-month posttreatment and correlated with overall survival (OS) and event-free survival (EFS). For each time point, analyses were limited to patients without lymphocytosis, so as to avoid possible biases from undocumented disease progressions. Lymphopenia (ALC < 1.0 × 10³ cells/μL) at 3 m after FCR (69% of patients n = 68), was associated with a longer OS (5y OS 91% vs 64%, P = .001), as were ALC ≤ 2 × 10³ cells/μL at 6 m (5y OS 85% vs 48%, P = .004) and ALC ≤ 1.8 × 10³ cells/μL at 9 m (5y OS 93% vs 54%, P = .009). A normal-range ALC (≤4 × 10³ cells/μL) at 12 m was also associated with a 91% 5y OS. Higher ALCs (but without lymphocytosis) were associated with shorter EFS (median EFS 27 months for ALC > 1.8 vs not reached for ALC ≤ 0.7 at 9 months, P < .0001). In conclusion, lower ALC levels in the first few months following frontline FCR therapy were associated with longer OS and EFS. Possible explanations may be that lower ALCs reflect deeper clonal suppression or protracted T_reg depletion. Absolute lymphocyte count levels may be a cheap and widely available prognostic marker, though the added value for clinical practice is the minimal residual disease era needs to be explored.

The potential combination of BCL-2 inhibitors and ibrutinib as frontline therapy in chronic lymphocytic leukemia

The recent development of small molecule inhibitors targeted at the B-cell receptor (BCR) pathway and the anti-apoptotic protein BCL-2 has revolutionized the care of patients with chronic lymphocytic leukemia (CLL). While durable responses to the BCR inhibitor ibrutinib have been observed in both previously untreated and relapsed/refractory CLL patients, residual disease is common in patients treated with single-agent ibrutinib. Interest remains high in therapeutic combinations that may lead to better quality remissions. A potential partner to ibrutinib with a distinct mechanism of action that is likely to lead to deeper responses is the BCL-2 inhibitor venetoclax. Preclinical studies have suggested synergism between inhibitors of BCR and BCL-2 and have paved the way to the development of ongoing clinical trials aimed at evaluating the combination of ibrutinib with venetoclax in CLL patients.

[Advances in the treatment of chronic lymphocytic leukaemia]

Chronic lymphocytic leukemia (CLL), a proliferation of mature B cells, is one of the most prevalent haematological malignancies. Progress has been made in its treatment during the last few decades, and chemoimmunotherapy based on fludarabine, cyclophosphamide and rituximab is considered the treatment of choice for patients with standard-risk CLL and good performance status. However, due to the characterization of high-risk biological subgroups and its presentation in elderly patients and/or with comorbidities, targeted therapies, such as B-cell receptor inhibitors, have been developed and approved during the last few years. The current review examines traditional therapeutic strategies and focuses on new small molecules that already represent promising elements of the CLL treatment landscape.

Long-term remissions after FCR chemoimmunotherapy in previously untreated patients with CLL: updated results of the CLL8 trial

Despite promising results with targeted drugs, chemoimmunotherapy with fludarabine, cyclophosphamide (FC), and rituximab (R) remains the standard therapy for fit patients with untreated chronic lymphocytic leukemia (CLL). Herein, we present the long-term follow-up of the randomized CLL8 trial reporting safety and efficacy of FC and FCR treatment of 817 treatment-naïve patients with CLL. The primary end point was progression-free survival (PFS). With a median follow-up of 5.9 years, median PFS were 56.8 and 32.9 months for the FCR and FC group (hazard ratio [HR], 0.59; 95% confidence interval [CI], 0.50-0.69, P < .001). Median overall survival (OS) was not reached for the FCR group and was 86.0 months for the FC group (HR, 0.68; 95% CI, 0.54-0.89, P = .001). In patients with mutated IGHV (IGHV MUT), FCR improved PFS and OS compared with FC (PFS: HR, 0.47; 95% CI, 0.33-0.68, P < .001; OS: HR, 0.62; 95% CI, 0.34-1.11, P = .1). This improvement remained applicable for all cytogenetic subgroups other than del(17p). Long-term safety analyses showed that FCR had a higher rate of prolonged neutropenia during the first year after treatment (16.6% vs 8.8%; P = .007). Secondary malignancies including Richter's transformation occurred in 13.1% in the FCR group and in 17.4% in the FC group (P = .1). First-line chemoimmunotherapy with FCR induces long-term remissions and highly relevant improvement in OS in specific genetic subgroups of fit patients with CLL, in particular those with IGHV MUT. This trial was registered at www.clinicaltrials.gov as #NCT00281918.

Radioimmunotherapy consolidation using 131I-tositumomab for patients with chronic lymphocytic leukemia or small lymphocytic lymphoma in first remission

Despite initial responses to chemoimmunotherapy, relapse and minimal residual disease (MRD) remain major issues in treatment of chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) patients. We administered (131)I-tositumomab to patients in complete response (CR) or partial response (PR) after induction chemotherapy. Toxicities and rate of PR to CR conversion and MRD elimination were assessed three months later. The study stopped prematurely after enrolling 16 patients. Four (25%) were in CR, 12 (75%) in PR, and 12 (75%) had MRD. Three months after treatment with (131)I-tositumomab, CR was achieved (n = 8; 50%) or sustained (n = 4; 25%) in 12 patients and MRD was eliminated in four of 12 patients (33%). Hematologic toxicities were anemia in one patient (6%), neutropenia in 13 (81%), and thrombocytopenia in eight (50%). Two patients (12%) developed MDS 17 and 20 months after consolidation. Consolidation with (131)I-tositumomab for CLL/SLL patients in first remission is feasible and may provide the benefit of converting PR to CR and/or eliminating MRD.

Management of chronic lymphocytic leukemia (CLL) in the era of B-cell receptor signal transduction inhibitors

The treatment of patients with chronic lymphocytic leukemia (CLL), an indolent B-cell lymphoma is in the midst of a transformation. There are a large number of promising new therapeutic agents and cellular therapies being studied which exhibit remarkable activity, favorable toxicity profiles, convenient administration schedules, and treatment options are rapidly expanding. The recent advances in the management of CLL exemplify the value of translational medicine. This review highlights key aspects of B-cell receptor (BCR) signaling in relation to novel inhibitors of the BCR signaling pathway, currently at various stages of preclinical and clinical development.

A canadian perspective on the first-line treatment of chronic lymphocytic leukemia

Despite important advances in the treatment of first-line chronic lymphocytic leukemia (CLL) over the past decade, CLL remains an incurable disease with significant unmet needs. The combination of rituximab with fludarabine and cyclophosphamide (FCR) significantly improved overall survival and progression-free survival compared with fludarabine and cyclophosphamide alone in first-line treatment of CLL. However, because of its high toxicity, FCR is only recommended for younger, fit patients who can tolerate the treatment. This excludes a large fraction of CLL patients who are elderly and/or who have comorbidities. Thus, determining the appropriate treatment choices for this group of patients who are unfit for FCR treatment is a significant challenge in CLL. Current treatment choices in Canadian practice include bendamustine with rituximab, fludarabine with rituximab, and chlorambucil with rituximab. Two novel monoclonal antibodies, ofatumumab and obinutuzumab, have also recently received Health Canada approval for the first-line treatment of CLL patients in combination with chlorambucil. In addition, the Bruton tyrosine kinase inhibitor, ibrutinib, has recently been approved by Health Canada for the first-line treatment of CLL patients with deletion 17p. In the coming years, several other novel agents that are being developed are likely to change the CLL treatment landscape dramatically, however, because these novel agents are currently unavailable, the purpose of this review is to recommend the best treatment approaches in Canada using currently available therapies.

Evaluation and Management of Bacterial and Fungal Infections Occurring in Patients with a Hematological Malignancy: A 2011 Update

Patients with a hematological malignancy are a heterogeneous patient population who are afflicted with diseases that range from rapidly fatal acute leukemia to indolent lymphoma or chronic leukemia. Treatment options for these patients range from observation to hematopoietic stem cell transplantation (HSCT), but all patients are more susceptible to infection. The problem of infection is dynamic with continued shifts in pathogenic organisms and microbial susceptibilities, new treatment regimens that further diminish immune function, and patients receiving treatment who are now older and frailer. The classic patterns of immunodeficiency for patients with a hematological malignancy include: periods of profound neutropenia, increased iatrogenic risks (i.e., central vascular catheters), and cellular immune suppression that affects HSCT recipients, patients with lymphoid malignancies, and those receiving treatment with corticosteroids or agents like alemtuzumab [1–4]. Recent advances in antimicrobial drug development, new technology, clinical trial results, and further clinical experience have enhanced the database on which to make infection prophylaxis and treatment decisions. However, the practicing clinician must remember that the majority of basic infection management principles for patients who are neutropenic remain unchanged.

Comparison on therapeutic effects of RFT and RCTVP regimen in the treatment of patients with indolent B-cell lymphoma in China

To compare the efficacy and safety of RFT (retuximab, fludarabine, pirarubicin) with RCTVP (retuximab, cyclophophamide, pirarubicin, vindesine and prednisone) in 248 indolent B-cell non-Hodgkin's lymphoma (NHL) patients. Two hundred and forty-eight patients with indolent B-cell NHL were treated with combined chemotherapy, including RFT and RCTVP, from January 2002 to December 2010 in Tianjin Cancer Hospital. The rate of response, toxicity and long-term survival for the two regimens were analyzed retrospectively. For the previously untreated patients, overall response rate for RFT arm and RCTVP arm was 71.7 and 70.6%, and complete response rate was 47.5 and 54.9%, respectively (P>0.05). For the refractory and relapsed patients, overall response (OR) rate and complete response (CR) rate were significantly improved in the RFT arm versus the RCTVP arm (P<0.05). There were no statistically significant differences in overall survival (OS) between treatment groups. Comparing with RCTVP regimen, fludarabine-based treatment was associated with superior PFS both in previously untreated, refractory and relapsed patients. WHO grades 3 and 4 hematological adverse events were more common in the RFT arm. Neurotoxicity was more common in the RCTVP arm. For the previously untreated patients, there was no difference between RFT arm and RCTVP arm on OR and CR rates. For the refractory and relapsed indolent B-cell NHL patients who received RFT regimen achieved higher OR and CR rates compared with RCTVP-treated patients. No differences in OS were noted. RFT regimen was associated with superior PFS both in previously untreated, refractory and relapsed patients. RFT regimen is effective and well tolerated for patients with untreated, refractory and relapsed indolent B-cell NHL.

Therapy-related myeloid neoplasms following fludarabine, cyclophosphamide, and rituximab (FCR) treatment in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma

This study is focused on therapy-related myeloid neoplasms after the most promising frontline FCR (fludarabine, cyclophosphamide, and rituximab) therapy in previously untreated chronic lymphocytic leukemia patients. A total of 28 therapy-related myeloid neoplasm patients were identified, including 19 patients from 3 well-controlled FCR frontline trials (n=426 patients), giving an estimated frequency of 4.5% (1.9-8.3%) in a follow-up period of 44 months (range 5-122 months). Clinically, therapy-related myeloid neoplasms could emerge directly from 'prolonged myelosuppression' after FCR (10 patients), or after achieving complete hematological recovery (n=18). The overall latency was 35 months (range 3-118 months), with the former group of 23 months and the latter 42 months (P<0.001). In all, 10 cases presented as therapy-related acute myeloid leukemia and 18 as therapy-related myelodysplastic syndromes. Abnormal cytogenetics was present in 26 of 27 (96%) patients, with frequent chromosomes 5 and 7 abnormalities. The median survival was 7 months after therapy-related myeloid neoplasms. Our results indicate that the risk of therapy-related myeloid neoplasms secondary to frontline FCR therapy may not be as high as previously reported after removing the confounding factor of previous cytotoxic exposure, but this risk increased with older age and likely growth factor co-administration. Therapy-related myeloid neoplasms after FCR therapy shares clinicopathological features with therapy-related myeloid neoplasms secondary to other alkylating agents, but has a shorter latency interval indicating possible synergetic effects of the nucleotide analog fludarabine. The fact that therapy-related myeloid neoplasms can directly emerge from 'prolonged myelosuppression' warrants a bone marrow examination to rule out therapy-related myeloid neoplasms in this clinical setting.

Clinical practice guideline for the use of antimicrobial agents in neutropenic patients with cancer: 2010 update by the infectious diseases society of america

This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia. Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving. What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens. Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care-associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Executive Summary: Clinical Practice Guideline for the Use of Antimicrobial Agents in Neutropenic Patients with Cancer: 2010 Update by the Infectious Diseases Society of America

This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia.

Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving.

What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens.

Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care–associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Determinants of the optimal first-line therapy for follicular lymphoma: a decision analysis

Combination immunochemotherapy is the most common approach for initial therapy of patients with advanced-stage follicular lymphoma, but no consensus exists as to the optimal selection or sequence of available regimens. We undertook this decision analysis to systematically evaluate the parameters affecting the choice of early therapy in patients with this disease. We designed a Markov model incorporating the three most commonly utilized regimens (RCVP, RCHOP, and RFlu) in combinations of first- and second-line therapies, with the endpoint of number of quality-adjusted life years (QALYs) until disease progression. Data sources included Phase II and Phase III trials and literature estimates of long-term toxicities and health state utilities. Meta-analytic methods were used to derive the values and ranges of regimen-related parameters. Based on our model, the strategy associated with the greatest number of expected quality-adjusted life years was treatment with RCHOP in first-line therapy followed by treatment with RFlu in second-line therapy (9.00 QALYs). Strategies containing RCVP either in first- or second-line therapy resulted in the lowest number of QALYs (range 6.24-7.71). Sensitivity analysis used to determine the relative contribution of each model parameter identified PFS after first-line therapy and not short-term QOL as the most important factor in prolonging overall quality-adjusted life years. Our results suggest that regimens associated with a longer PFS provide a greater number of total QALYs, despite their short-term toxicities. For patients without contraindications to any of these regimens, use of a more active regimen may maximize overall quality of life.