Eradication of minimal residual disease in B-cell chronic lymphocytic leukemia after alemtuzumab therapy is associated with prolonged survival

iVAC-XS15-CLL01: personalized multi-peptide vaccination in combination with the TLR1/2 ligand XS15 in CLL patients undergoing BTK-inhibitor-based regimens

Chronic lymphocytic leukemia (CLL) is the most common form of leukemia among adults in Western countries. Despite the introduction of targeted therapies, including first-line Bruton's tyrosine kinase inhibitor (BTKi) treatment, CLL remains largely incurable. Frequent disease relapses occur due to remaining treatment-resistant CLL cells, calling for novel therapies to eliminate minimal residual disease (MRD). Peptide-based vaccination targeting human leucocyte antigen (HLA)-presented CLL-associated antigens represents a promising, low-side-effect therapeutic option to optimize treatment responses and eliminate residual tumor cells by inducing an anti-leukemic immune response. The iVAC-XS15-CLL01 trial is an open-label, first-in-human (FIH) Phase I trial, evaluating the CLL-VAC-XS15 vaccine in CLL patients undergoing BTKi-based therapy. The vaccine was developed from HLA-presented CLL-associated antigen peptides, identified through comparative mass-spectrometry-based immunopeptidome analyses of CLL versus healthy samples in a previous study. To facilitate rapid and cost-effective deployment, vaccine peptides are selected for each patient from a pre-manufactured "peptide warehouse" based on the patient's individual HLA allotype and CLL immunopeptidome. The trial enrolls 20 CLL patients, who receive up to three doses of the vaccine, adjuvanted with the toll-like-receptor (TLR) 1/2 ligand XS15 and emulsified in Montanide ISA 51 VG. The primary objective of the iVAC-XS15-CLL01 trial is to assess the safety and immunogenicity of the CLL-VAC-XS15 vaccine. Secondary objectives are to evaluate the vaccine impact on MRD, progression-free survival, and overall survival, as well as comprehensive immunophenotyping to characterize vaccine-induced T-cell responses. This Phase I trial aims to advance CLL treatment by enhancing immune-mediated disease clearance and guiding the design of subsequent Phase II/III trials to implement a new therapeutic strategy for CLL patients.

Predicting progression-free survival from measurable residual disease in chronic lymphocytic leukemia

Association between measurable residual disease (MRD) and survival outcomes in chronic lymphocytic leukemia (CLL) has often been reported. However, limited quantitative analyses over large datasets have been undertaken to establish the predictive power of MRD. Here, we provide a comprehensive assessment of published MRD data to explore the utility of MRD in the prediction of progression-free survival (PFS). We undertook two independent analyses, which leveraged available published data to address two complimentary questions. In the first, data from eight clinical trials was modeled via a meta-regression approach, showing that median PFS can be predicted from undetectable MRD rates at 3-6 months of post-treatment. The resulting model can be used to predict the probability of technical success of a planned clinical trial in chemotherapy. In the second, we investigated the evidence for predicting PFS from competing MRD metrics, for example baseline value and instantaneous MRD value, via a joint modeling approach. Using data from four small studies, we found strong evidence that including MRD metrics in joint models improves predictions of PFS compared with not including them. This analysis suggests that incorporating MRD is likely to better inform individual progression predictions. It is therefore proposed that systematic MRD collection should be accompanied by modeling to generate algorithms that inform patients' progression.

Flow cytometric evaluation of measurable residual disease in chronic lymphocytic leukemia: Where do we stand?

Measurable residual disease (MRD) has emerged as a relevant parameter of response to therapy in chronic lymphocytic leukemia (CLL). Although several methods have been developed, flow cytometry has emerged as the most useful and standardized approach to measure and quantify MRD. The improved sensitivity of MRD measurements has been paralleled by the development of more effective therapeutic strategies for CLL, increasing the applicability of MRD detection in this setting. Chemotherapy and chemoimmunotherapy have firstly demonstrated their ability to obtain a deep MRD. Combined targeted therapies are also demonstrating a high molecular response rate and prospective trials are exploring the role of MRD to guide the duration of treatment in this setting. In this review we briefly summarize what we have learned about MRD with emphasis on its flow cytometric detection.

Immunopeptidome Diversity in Chronic Lymphocytic Leukemia Identifies Patients with Favorable Disease Outcome

Simple Summary

Immunosurveillance of cancer is mediated by T cell-based recognition of tumor-associated antigens, i.e., short peptides that are presented on the surface of cells on human leukocyte antigen (HLA) molecules. This encourages the analysis of the entirety of HLA-presented peptides, the so-called immunopeptidome, of malignant and benign cells, in order to identify novel therapeutic targets presented exclusively on malignant cells. In the present study, we aim to investigate the role of previously described immunopeptidome-defined antigen presentation in chronic lymphocytic leukemia (CLL) patients for clinical characteristics and disease outcome. We observed that higher yields of presented total and CLL-exclusive peptides were associated with a more favorable disease course, suggesting efficient immunosurveillance in a subgroup of patients and the possibility of further investigating T cell-based therapeutic approaches for CLL.

Abstract

Chronic lymphocytic leukemia (CLL) is characterized by recurrent relapses and resistance to treatment, even with novel therapeutic approaches. Despite being considered as a disease with low mutational burden and thus poor immunogenic, CLL seems to retain the ability of eliciting specific T cell activation. Accordingly, we recently found non-mutated tumor-associated antigens to play a central role in CLL immunosurveillance. Here, we investigated the association of total and CLL-exclusive HLA class I and HLA class II peptide presentation in the mass spectrometry-defined immunopeptidome of leukemic cells with clinical features and disease outcome of 57 CLL patients. Patients whose CLL cells present a more diverse immunopeptidome experienced fewer relapses. During the follow-up phase of up to 10 years, patients with an HLA class I-restricted presentation of high numbers of total and CLL-exclusive peptides on their malignant cells showed a more favorable disease course with a prolonged progression-free survival (PFS). Overall, our results suggest the existence of an efficient T cell-based immunosurveillance mediated by CLL-associated tumor antigens, supporting ongoing efforts in developing T cell-based immunotherapeutic strategies for CLL.

Chronic lymphocytic leukemia: 2022 update on diagnostic and therapeutic procedures

DISEASE OVERVIEW

Chronic lymphocytic leukemia (CLL) is one of the most frequent types of leukemia. It typically occurs in elderly patients and has a highly variable clinical course. Leukemic transformation is initiated by specific genomic alterations that interfere with the regulation of proliferation and of apoptosis in clonal B-cells.

DIAGNOSIS

The diagnosis is established by blood counts, blood smears, and immunophenotyping of circulating B-lymphocytes, which identify a clonal B-cell population carrying the CD5 antigen as well as typical B-cell markers.

PROGNOSIS AND STAGING

The clinical staging systems provide prognostic information by using the results of physical examination and blood counts. Various biological and genetic markers provide additional prognostic information. Deletions of the short arm of chromosome 17 (del[17p]) and/or mutations of the TP53 gene predict resistance to chemoimmunotherapy and a shorter time to progression with most targeted therapies. The CLL international prognostic index integrates genetic, biological, and clinical variables to identify distinct risk groups of patients with CLL.

THERAPY

Only patients with active or symptomatic disease or with advanced Binet or Rai stages require therapy. When treatment is indicated, several therapeutic options exist: a combination of the B-cell lymphoma 2 (BCL2) inhibitor venetoclax with obinutuzumab, monotherapy with inhibitors of Bruton tyrosine kinase (BTK) such as ibrutinib and acalabrutinib, or chemoimmunotherapy. At relapse, the initial treatment may be repeated, if the treatment-free interval exceeds 3 years. If the disease relapses earlier, therapy should be changed using an alternative regimen. Patients with a del(17p) or TP53 mutation are usually resistant to chemotherapy and should, therefore, be treated with targeted agents.

FUTURE CHALLENGES

Combinations of targeted agents are now being investigated to create efficient, potentially curative therapies of CLL with fixed duration. One of the most relevant questions currently addressed in clinical trials is the comparison of monotherapies with BTK inhibitors with fixed duration combination therapies. Moreover, the optimal sequencing of targeted therapies remains to be determined. Alternative therapies are needed for patients with BTK and BCL2 inhibitor double-refractory disease.

Infection risk and prophylaxis in patients with lymphoid cancer

Infections are a common cause of morbidity and mortality in patients with lymphoid cancer. With evolving cancer therapeutics, including new targeted and immunotherapies, clinicians need to be aware of additional risk factors and infections that may arise in patients treated with these agents. This "How I Treat" article will highlight fundamental issues including risk factors for infection, infectious diseases screenings and antimicrobial prophylaxis recommendations in patients with lymphoid cancers. We present 4 scenarios of patients with lymphoid cancers with varied infections and describe a treatment approach based on a combination of evidence-based data and experience, as there are limitations in objective infection data especially with newer agents. The goal of this discussion is to provide a framework for institutions and health care providers to develop their own approach in preventing and treating infections in patients with lymphoid cancer.

Measurable residual disease in chronic lymphocytic leukemia: expert review and consensus recommendations

Assessment of measurable residual disease (often referred to as "minimal residual disease") has emerged as a highly sensitive indicator of disease burden during and at the end of treatment and has been correlated with time-to-event outcomes in chronic lymphocytic leukemia. Undetectable-measurable residual disease status at the end of treatment demonstrated independent prognostic significance in chronic lymphocytic leukemia, correlating with favorable progression-free and overall survival with chemoimmunotherapy. Given its utility in evaluating depth of response, determining measurable residual disease status is now a focus of outcomes in chronic lymphocytic leukemia clinical trials. Increased adoption of measurable residual disease assessment calls for standards for nomenclature and outcomes data reporting. In addition, many basic questions have not been systematically addressed. Here, we present the work of an international, multidisciplinary, 174-member panel convened to identify critical questions on key issues pertaining to measurable residual disease in chronic lymphocytic leukemia, review evaluable data, develop unified answers in conjunction with local expert input, and provide recommendations for future studies. Recommendations are presented regarding methodology for measurable residual disease determination, assay requirements and in which tissue to assess measurable residual disease, timing and frequency of assessment, use of measurable residual disease in clinical practice versus clinical trials, and the future usefulness of measurable residual disease assessment. Nomenclature is also proposed. Adoption of these recommendations will work toward standardizing data acquisition and interpretation in future studies with new treatments with the ultimate objective of improving outcomes and curing chronic lymphocytic leukemia.

Highly Sensitive and Accurate Assessment of Minimal Residual Disease in Chronic Lymphocytic Leukemia Using the Novel CD160-ROR1 Assay

Undetectable minimal residual disease (MRD) in Chronic Lymphocytic Leukemia (CLL) has a favorable prognostic outcome compared with MRD that can be detected. This study investigated a flow cytometric assay (CD160-ROR1FCA) targeting the tumor-specific antigens CD160 and receptor tyrosine kinase-like orphan receptor 1 (ROR1), along with CD2, CD5, CD19, CD45. CD160-ROR1FCA was compared with the originally published 8-colour European Research Initiative for CLL (ERIC) gold-standard assay for CLL MRD detection. CD160-ROR1FCA had a limit of detection of 0.001% and showed strong correlation with ERIC (R = 0.98, p < 0.01) with negligible differences in MRD detection (bias -0.3152 95%CI 5.586 to -6.216). Using CD160-ROR1FCA, increased expression of both CD160 and ROR1 was found in Monoclonal B cell Lymphocytosis (MBL) compared to low-level polyclonal B-cell expansions (p < 0.01). Patients in CR and with undetectable MRD had a longer EFS (not reached) than those in CR but with detectable MRD (756 days, p < 0.01) versus 113 days in patients with partial remission (p < 0.01). Patients with MRD levels of >0.01 to 0.1% had a longer EFS (2,333 days), versus levels between 0.1 to 1% (1,049 days). CD160-ROR1FCA is a novel assay for routine CLL MRD measurement and for MBL detection. MRD status assessed by CD160-ROR1FCA after CLL treatment correlated with EFS.

Current Perspectives on Therapy for Chronic Lymphocytic Leukemia

Therapy for chronic lymphocytic leukemia has improved dramatically over the past decade with the introduction of new targeted therapies and a paradigm shift toward targeted therapies for the majority of patients. Better understanding of prognostic factors has helped tailor therapy for individual patients, and work continues to identify optimal therapy for each patient. When therapy is required, most patients will be treated with targeted therapies, either the Bruton tyrosine kinase (BTK) inhibitors ibrutinib or acalabrutinib or the BCL-2 inhibitor venetoclax in combination with obinutuzumab. Without head-to-head comparisons showing differential efficacy among these options, considerations regarding safety, patient preference, and ability to sequence therapy currently influence treatment decisions. Also, clinical trials investigating combinations of these therapies have the potential to further change the standard of care. In this review, we cover the currently available options for the frontline treatment of chronic lymphocytic leukemia (CLL) and discuss safety considerations and toxicity management with each agent as well as novel combination strategies currently under investigation.

Obinutuzumab plus fludarabine and cyclophosphamide in previously untreated, fit patients with chronic lymphocytic leukemia: a subgroup analysis of the GREEN study

GREEN (NCT01905943) is a nonrandomized, open-label, single-arm, phase 3b study investigating the safety and efficacy of obinutuzumab alone or in combination with chemotherapy in chronic lymphocytic leukemia (CLL). We report the preplanned subgroup analysis of 140 previously untreated, fit CLL patients who received obinutuzumab plus fludarabine and cyclophosphamide (G-FC). The primary endpoint was safety and tolerability. Efficacy was the secondary endpoint. Obinutuzumab 1000 mg was administered intravenously on Day (D)1 (dose split D1‒2), D8 and D15 of Cycle (C)1, and D1 of C2-6 (28-day cycles). Standard intravenous/oral doses of fludarabine and cyclophosphamide were administered on D1-3 of C1-6. Overall, 87.1% of patients experienced grade ≥ 3 adverse events (AEs), including neutropenia (67.1%) and thrombocytopenia (17.1%). Serious AEs were experienced by 42.1% of patients. Rates of grade ≥ 3 infusion-related reactions and infections were 19.3% and 15.7%, respectively. Overall response rate was observed in 90.0%, with 46.4% of patients achieving complete response (CR; including CR with incomplete marrow recovery). Minimal residual disease negativity rates were 64.3% in peripheral blood and 35.7% in bone marrow (intent-to-treat analysis). After a median observation time of 25.6 months, 2 year progression-free survival was 91%. Frontline G-FC represents a promising treatment option for fit patients with CLL.

Chronic lymphocytic leukemia: 2020 update on diagnosis, risk stratification and treatment

DISEASE OVERVIEW

Chronic lymphocytic leukemia (CLL) is the commonest leukemia in western countries. The disease typically occurs in elderly patients and has a highly variable clinical course. Leukemic transformation is initiated by specific genomic alterations that impair apoptosis of clonal B-cells.

DIAGNOSIS

The diagnosis is established by blood counts, blood smears, and immunophenotyping of circulating B-lymphocytes, which identify a clonal B-cell population carrying the CD5 antigen, as well as typical B-cell markers.

PROGNOSIS

The two similar clinical staging systems, Rai and Binet, create prognostic information by using results of physical examination and blood counts. Various biological and genetic markers also have prognostic value. Deletions of the short arm of chromosome 17 (del [17p]) and/or mutations of the TP53 gene, predict resistance to chemoimmunotherapy and a shorter time to progression, with most targeted therapies. A comprehensive, international prognostic score (CLL-IPI) integrates genetic, biological and clinical variables to identify distinct risk groups of CLL patients.

THERAPY

Only patients with active or symptomatic disease, or with advanced Binet or Rai stages require therapy. When treatment is indicated, several options exist for most CLL patients: a combination of venetoclax with obinutuzumab, ibrutinib monotherapy, or chemoimmunotherapy. For physically fit patients younger than 65 (in particular when presenting with a mutated IGVH gene), chemoimmunotherapy with fludarabine, cyclophosphamide and rituximab remains a standard therapy, since it may have curative potential. At relapse, the initial treatment may be repeated, if the treatment-free interval exceeds 3 years. If the disease relapses earlier, therapy should be changed using an alternative regimen. Patients with a del (17p) or TP53 mutation are a different, high-risk category and should be treated with targeted agents. An allogeneic SCT may be considered in relapsing patients with TP53 mutations or del (17p), or patients that are refractory to inhibitor therapy.

FUTURE CHALLENGES

Targeted agents (ibrutinib, idelalisib, venetoclax, obinutuzumab) will be increasingly used in combination to allow for short, but potentially definitive therapies of CLL. It remains to be proven that they generate a superior outcome when compared to monotherapies with inhibitors of Bruton tyrosine kinase, which can also yield long-lasting remissions. Moreover, the optimal sequencing of drug combinations is unknown. Therefore, CLL patients should be treated in clinical trials whenever possible.

Minimal Residual Disease in Chronic Lymphocytic Leukemia: A New Goal?

In chronic lymphocytic leukemia (CLL), there is a growing interest for minimal residual disease (MRD) monitoring, due to the availability of drug combinations capable of unprecedented complete clinical responses. The standardized and most commonly applied methods to assess MRD in CLL are based on flow cytometry (FCM) and, to a lesser extent, real-time quantitative PCR (RQ-PCR) with allele-specific oligonucleotide (ASO) primers of immunoglobulin heavy chain genes (IgH). Promising results are being obtained using droplet digital PCR (ddPCR) and next generation sequencing (NGS)-based approaches, with some advantages and a potential higher sensitivity compared to the standardized methodologies. Plasma cell-free DNA can also be explored as a more precise measure of residual disease from all different compartments, including the lymph nodes. From a clinical point of view, CLL MRD quantification has proven an independent prognostic marker of progression-free survival (PFS) and overall survival (OS) after chemoimmunotherapy as well as after allogeneic transplantation. In the era of mechanism-driven drugs, the paradigms of CLL treatment are being revolutionized, challenging the use of chemoimmunotherapy even in first-line. The continuous administration of ibrutinib single agent has led to prolonged PFS and OS in relapsed/refractory and treatment naïve CLL, including those with TP53 deletion/mutation or unmutated IGHV genes, though the clinical responses are rarely complete. More recently, chemo-free combinations of venetoclax+rituximab, venetoclax+obinutuzumab or ibrutinib+venetoclax have been shown capable of inducing undetectable MRD in the bone marrow, opening the way to protocols exploring a MRD-based duration of treatment, aiming at disease eradication. Thus, beside a durable disease control desirable particularly for older patients and/or for those with comorbidities, a MRD-negative complete remission is becoming a realistic prospect for CLL patients in an attempt to obtain a long-lasting eradication and possibly cure of the disease. Here we discuss the standardized and innovative technical approaches for MRD detection in CLL, the clinical impact of MRD monitoring in chemoimmunotherapy and chemo-free trials and the future clinical implications of MRD monitoring in CLL patients outside of clinical trials.

Cytomegalovirus primary infection in a patient with multiple sclerosis treated with alemtuzumab

Alemtuzumab is an anti-CD52 monoclonal antibody approved for the treatment of multiple sclerosis (MS). It produces rapid depletion of T and B lymphocytes, which could predispose to opportunistic infections. We report one patient with MS who develops cytomegalovirus (CMV) primary infection after a third cycle of alemtuzumab, with spontaneous recovery associated with rapid lymphocyte reconstitution.

Pentostatin, Cyclophosphamide, and Rituximab Followed by Alemtuzumab for Relapsed or Refractory Chronic Lymphocytic Leukemia: A Phase 2 Trial of the ECOG-Acrin Cancer Research Group (E2903)

Patients with relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL) may benefit from salvage chemoimmunotherapy (CIT). To explore further the use of CIT in the pre-novel agent era, ECOG-ACRIN undertook a phase 2 trial (E2903) for R/R CLL utilizing pentostatin, cyclophosphamide, and rituximab (PCR) followed by a consolidation course of alemtuzumab. This trial enrolled 102 patients with a median age of 64 years. Treatment consisted of 6 cycles of PCR followed by alemtuzumab for either 4 or 18 weeks depending on the initial response to PCR. The overall response after PCR (complete remission, CR, nodular partial remission, nPR, and partial remission, PR) was 55%. Major responses (CR or nPR) were achieved in 6%. The median overall survival (OS) and the median progression-free survival were 28 and 12 months, respectively. The most serious nonlethal adverse events were myelosuppression, febrile neutropenia, fatigue, nausea, and hyponatremia. PCR is an effective and well-tolerated nucleoside-based regimen for heavily pretreated CLL patients with R/R disease. The addition of alemtuzumab to CLL patients with a minor response (PR) or stable disease did not result in a significant number of higher responses (CR or nPR) nor an improvement in OS.

Clinical Flow-Cytometric Testing in Chronic Lymphocytic Leukemia

Flow-cytometric demonstration of the typical chronic lymphocytic leukemia (CLL) immunophenotype is vital for diagnosis. CLL has a characteristic immunophenotype, expressing CD5, CD19, dim CD20, dim CD22, CD23, bright CD43, dim CD45, dim to negative CD79b, dim CD81, CD200, and dim monoclonal surface immunoglobulin. This characteristic immunophenotype allows a definitive diagnosis and the ruling out of another leukemia or lymphoma. Flow cytometry also provides important prognostic information and accurate assessment of response to therapy. Here we describe optimal specimen collection, red cell lysis, appropriate panel, cell staining, acquisition on a flow cytometer, and analysis for CLL specimens.

On the architecture of translational research designed to control chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) has been 1 of the most dynamic fields of clinical research over the last 2 decades. Important advances in understanding the biology of CLL have led to the development of new prognostic and diagnostic tools. Concurrently, several recently approved new agents hold the potential to fundamentally change the management of this leukemia and have started to improve clinical outcomes for patients. This conceptual review summarizes the major recent insights regarding the biology of CLL, the technological advances that have allowed refinement of the prognostication of the clinical course, and the new therapeutic strategies that are currently under investigation to further ameliorate the outcome for patients with CLL.

[Minimal residual disease in chronic lymphocytic leukemia: A still current issue in 2018]

Minimal residual disease (MRD) is widely used in oncohematology. In chronic lymphocytic leukemia (CLL), it can be measured by flow cytometry or polymerase chain reaction and is getting a greater place, owing to the dramatic therapeutic advances in the management this disease. As MRD decrease after chemoimmunotherapy is associated with improved progression free and overall survivals, its measure is now recommended as a surrogate marker for cytotoxic drugs licensures. This association is independent from treatment received and raises a few questions, such as sequential MRD measures to stop treatment in case of an early deep response and on the opposite, treatment continuation until reaching undetectable MRD (with the possible use of maintenance therapy). Furthermore, following MRD after a cytotoxic treatment could lead clinical trials investigators to propose pre-emptive treatments in case of MRD re-growth, to avoid overt relaspe. MRD re-growth kinetics and CD4 count after treatment completion can improve MRD-based survival predictions. On the other hand, BCR inhibitors do not lead to undetectable MRD, but their association with chemoimmunotherapy increases the proportion of patients reaching that goal. Moreover, BCL2 inhibitors do lead to deep response including in the relapse/refractory setting, giving to MRD a central place in currently investigated treatments evaluation.

Remission maintenance treatment options in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) treatment has come a long way in the last two decades, producing increases in tumor control to the point of generating sizeable numbers of patients with undetectable minimal residual disease and creating overall survival benefits in randomized comparisons. Most of this has been achieved by limited-term treatment approaches including chemotherapeutic and immune-therapeutic drugs. More recently, novel therapies targeting signaling pathways essential for the survival of the neoplastic clones have opened avenues that provide disease control in long-term treatment designs, mostly without producing deep remissions. In this disease, where current treatments are largely unable to effect a cure, prolonged therapy designs using maintenance approaches are explored and 5 randomized studies of maintenance have recently been published. This review shall summarize available results from a systematic literature review in a clinical context and outline basic biology principles that should be heeded in this regard.

Obinutuzumab plus bendamustine in previously untreated patients with CLL: a subgroup analysis of the GREEN study

GREEN (NCT01905943) is a non-randomized, open-label phase IIIb study investigating obinutuzumab alone or plus chemotherapy in chronic lymphocytic leukemia (CLL). We report a preplanned subgroup analysis of 158 previously untreated CLL patients receiving obinutuzumab-bendamustine (G-B). Patients received six 28-day cycles (C) of G-B: obinutuzumab day (D)1/D2 of C1 (25 mg D1/975 mg D2), 1000 mg D8 and D15 of C1, and D1 of C2-6; and bendamustine 70/90 mg/m2 D1 and D2 of C1-6. The primary endpoint was safety/tolerability. Grade ≥3 adverse events (AEs) occurred in 82.3% of patients, including neutropenia (49.4%), thrombocytopenia (12.0%) and febrile neutropenia (10.8%). Serious AEs included neutropenia (12.7%), febrile neutropenia (9.5%) and pneumonia (7.6%). Rates of grade ≥3 infections and infusion-related reactions were 20.3% and 17.1%, respectively. Due to tumor lysis syndrome (TLS; 8.2%), including two associated fatalities (one in another study cohort), additional risk-minimization measures were implemented. Overall response rate was 81.0%. After 32.8 months' median observation time, 2-year progression-free survival was 81.8%. Minimal residual disease was undetectable in 59.5% (94/158) and 27.8% (44/158) of patients for blood and bone marrow, respectively. Frontline G-B appears to have manageable toxicity with clinical activity in CLL. Careful TLS risk assessment, pretreatment and monitoring is required.

Fludarabine and rituximab with escalating doses of lenalidomide followed by lenalidomide/rituximab maintenance in previously untreated chronic lymphocytic leukaemia (CLL): the REVLIRIT CLL-5 AGMT phase I/II study

Despite recent advances, chemoimmunotherapy remains a standard for fit previously untreated chronic lymphocytic leukaemia patients. Lenalidomide had activity in early monotherapy trials, but tumour lysis and flare proved major obstacles in its development. We combined lenalidomide in increasing doses with six cycles of fludarabine and rituximab (FR), followed by lenalidomide/rituximab maintenance. In 45 chemo-naive patients, included in this trial, individual tolerability of the combination was highly divergent and no systematic toxicity determining a maximum tolerated dose was found. Grade 3/4 neutropenia (71%) was high, but only 7% experienced grade 3 infections. No tumour lysis or flare > grade 2 was observed, but skin toxicity proved dose-limiting in nine patients (20%). Overall and complete response rates after induction were 89 and 44% by intention-to-treat, respectively. At a median follow-up of 78.7 months, median progression-free survival (PFS) was 60.3 months. Minimal residual disease and immunoglobulin variable region heavy chain mutation state predicted PFS and TP53 mutation most strongly predicted OS. Baseline clinical factors did not predict tolerance to the immunomodulatory drug lenalidomide, but pretreatment immunophenotypes of T cells showed exhausted memory CD4 cells to predict early dose-limiting non-haematologic events. Overall, combining lenalidomide with FR was feasible and effective, but individual changes in the immune system seemed associated with limiting side effects. clinicaltrials.gov (NCT00738829) and EU Clinical Trials Register (www.clinicaltrialsregister.eu, 2008-001430-27)

Minimal residual disease in chronic lymphocytic leukemia: A consensus paper that presents the clinical impact of the presently available laboratory approaches

Chronic lymphocytic leukemia (CLL) is a malignancy defined by the accumulation of mature lymphocytes in the lymphoid tissues, bone marrow, and blood. Therapy for CLL is guided according to the Rai and Binet staging systems. Nevertheless, state-of-the-art protocols in disease monitoring, diagnostics, and prognostics for CLL are based on the assessment of minimal residual disease (MRD). MRD is internationally considered to be the level of disease that can be detected by sensitive techniques and represents incomplete treatment and a probability of disease relapse. MRD detection has been continuously improved by the quick development of both flow cytometry and molecular biology technology, as well as by next-generation sequencing. Considering that MRD detection is moving more and more from research to clinical practice, where it can be an independent prognostic marker, in this paper, we present the methodologies by which MRD is evaluated, from translational research to clinical practice.

iwCLL guidelines for diagnosis, indications for treatment, response assessment, and supportive management of CLL

The previous edition of the consensus guidelines of the International Workshop on Chronic Lymphocytic Leukemia (iwCLL), published in 2008, has found broad acceptance by physicians and investigators caring for patients with CLL. Recent advances including the discovery of the genomic landscape of the disease, the development of genetic tests with prognostic relevance, and the detection of minimal residual disease (MRD), coupled with the increased availability of novel targeted agents with impressive efficacy, prompted an international panel to provide updated evidence- and expert opinion-based recommendations. These recommendations include a revised version of the iwCLL response criteria, an update on the use of MRD status for clinical evaluation, and recommendations regarding the assessment and prophylaxis of viral diseases during management of CLL.

Guidelines for Diagnosis and Treatment of Chronic Lymphocytic Leukemia. Krohem B-Cll 2017

Recent developments in the diagnosis and treatment of chronic lymphocytic leukemia (B-CLL) have led to change of approach in clinical practice. New treatments have been approved based on the results of randomized multicenter trials for first line and for salvage therapy, and the results of numerous ongoing clinical trials are permanently providing new answers and further refining of therapeutic strategies. This is paralleled by substantial increase in understanding the disease genetics due to major advances in the next generation sequencing (NGS) technology. We define current position of the Croatian Cooperative Group for Hematologic Disease on diagnosis and treatment of CLL in the transition from chemo-immunotherapy paradigm into a new one that is based on new diagnostic stratification and unprecedented therapeutic results of B-cell receptor inhibitors (BRI) and Bcl-2 antagonists. This is a rapidly evolving field as a great number of ongoing clinical trials con-stantly accumulate and provide new knowledge. We believe that novel therapy research including genomic diagnosis is likely to offer new options that will eventually lead to time limited therapies without chemotherapy and more effective clinical care for B-CLL based on individualized precision medicine.

A model for predicting effect of treatment on progression-free survival using MRD as a surrogate end point in CLL

Our objective was to evaluate minimal residual disease (MRD) at the end of induction treatment with chemoimmunotherapy as a surrogate end point for progression-free survival (PFS) in chronic lymphocytic leukemia (CLL) based on 3 randomized, phase 3 clinical trials (ClinicalTrials.gov identifiers NCT00281918, NCT00769522, and NCT02053610). MRD was measured in peripheral blood (PB) from treatment-naïve patients in the CLL8, CLL10, and CLL11 clinical trials, and quantified by 4-color flow cytometry or allele-specific oligonucleotide real-time quantitative polymerase chain reaction. A meta-regression model was developed to predict treatment effect on PFS using treatment effect on PB-MRD. PB-MRD levels were measured in 393, 337, and 474 patients from CLL8, CLL10, and CLL11, respectively. The model demonstrated a statistically significant relationship between treatment effect on PB-MRD and treatment effect on PFS. As the difference between treatment arms in PB-MRD response rates increased, a reduction in the risk of progression or death was observed; for each unit increase in the (log) ratio of MRD^- rates between arms, the log of the PFS hazard ratio decreased by -0.188 (95% confidence interval, -0.321 to -0.055; P = .008). External model validation on the REACH trial and sensitivity analyses confirm the robustness and applicability of the surrogacy model. Our surrogacy model supports use of PB-MRD as a primary end point in randomized clinical trials of chemoimmunotherapy in CLL. Additional CLL trial data are required to establish a more precise quantitative relationship between MRD and PFS, and to support general applicability of MRD surrogacy for PFS across diverse patient characteristics, treatment regimens, and different treatment mechanisms of action.

Optimizing frontline therapy of CLL based on clinical and biological factors

The heterogeneity of the clinical course of chronic lymphocytic leukemia (CLL) ranges from an indolent course, where patients do not require therapy for many years, to a very aggressive disease, where treatment is required soon after diagnosis and relapses may occur early. The improved tools for prognostication allow predicting the outcome of patients with increasing reliability. Some markers also allow selecting more specific therapies with improved activity in the presence of certain genetic or clinical features of CLL. Of these markers, TP53 dysfunction, age, the presence of comorbidities and the immunoglobulin heavy-chain variable region gene mutational status, or serum markers such as β2-microglobulin have shown independent prognostic value in multiple prospective trials. During the last 10 years, multiple novel agents have become available. The advent of oral kinase inhibitors or Bcl-2 antagonists has provided highly effective options with acceptable toxicity. This manuscript summarizes the current evidence of the available treatment options and proposes an integrated algorithm for the frontline therapy of CLL.

Using prognostic models in CLL to personalize approach to clinical care: Are we there yet?

Four decades ago, two staging systems were developed to help stratify CLL into different prognostic categories. These systems, the Rai and the Binet staging, depended entirely on abnormal exam findings and evidence of anemia and thrombocytopenia. Better understanding of biologic, genetic, and molecular characteristics of CLL have contributed to better appreciating its clinical heterogeneity. New prognostic models, the GCLLSG prognostic index and the CLL-IPI, emerged. They incorporate biologic and genetic information related to CLL and are capable of predicting survival outcomes and cases anticipated to need therapy earlier in the disease course. Accordingly, these newer models are helping develop better informed surveillance strategies and ultimately tailor treatment intensity according to presence (or lack thereof) of certain prognostic markers. This represents a step towards personalizing care of CLL patients. We anticipate that as more prognostic factors continue to be identified, the GCLLSG prognostic index and CLL-IPI models will undergo further revisions.

Lenalidomide maintenance after first-line therapy for high-risk chronic lymphocytic leukaemia (CLLM1): final results from a randomised, double-blind, phase 3 study

BACKGROUND

The combined use of genetic markers and detectable minimal residual disease identifies patients with chronic lymphocytic leukaemia with poor outcome after first-line chemoimmunotherapy. We aimed to assess lenalidomide maintenance therapy in these high-risk patients.

METHODS

In this randomised, double-blind, phase 3 study (CLLM1; CLL Maintenance 1 of the German CLL Study Group), patients older than 18 years and diagnosed with immunophenotypically confirmed chronic lymphocytic leukaemia with active disease, who responded to chemoimmunotherapy 2-5 months after completion of first-line therapy and who were assessed as having a high risk for an early progression with at least a partial response after four or more cycles of first-line chemoimmunotherapy, were eligible if they had high minimal residual disease levels or intermediate levels combined with an unmutated IGHV gene status or TP53 alterations. Patients were randomly assigned (2:1) to receive either lenalidomide (5 mg) or placebo. Randomisation was done with a fixed block size of three, and was stratified according to the minimal residual disease level achieved after first-line therapy. Maintenance was started with 5 mg daily, and was escalated to the target dose of 15 mg. If tolerated, medication was administered until disease progression. The primary endpoint was progression-free survival according to an independent review. The pre-planned interim analysis done by intention to treat was done after 20% of the calculated progression-free survival events. This study is registered with ClinicalTrials.gov, number NCT01556776; treatment in the lenalidomide group is still ongoing.

FINDINGS

Between July 5, 2012, and March 15, 2016, 468 previously untreated patients with chronic lymphocytic leukaemia were screened for the study; 379 (81%) were not eligible. Recruitment was closed prematurely due to poor accrual after 89 of 200 planned patients were randomly assigned: 60 (67%) enrolled patients were assigned to the lenalidomide group and 29 (33%) to the placebo group, of whom 56 (63%) received lenalidomide and 29 (33%) placebo, with a median of 11·0 (IQR 4·5-20·5) treatment cycles at data cutoff. After a median observation time of 17·9 months (IQR 9·1-28·1), the hazard ratio for progression-free survival assessed by an independent review was 0·168 (95% CI 0·074-0·379). Median progression-free survival was 13·3 months (95% CI 9·9-19·7) in the placebo group and not reached (95% CI 32·3-not evaluable) in the lenalidomide group. The most frequent adverse events were skin disorders (35 patients [63%] in the lenalidomide group vs eight patients [28%] in the placebo group), gastrointestinal disorders (34 [61%] vs eight [28%]), infections (30 [54%] vs 19 [66%]), haematological toxicity (28 [50%] vs five [17%]), and general disorders (28 [50%] vs nine [31%]). One fatal adverse event was reported in each of the treatment groups (one [2%] patient with fatal acute lymphocytic leukaemia in the lenalidomide group and one patient (3%) with fatal multifocal leukoencephalopathy in the placebo group).

INTERPRETATION

Lenalidomide is an efficacious maintenance therapy reducing the relative risk of progression in first-line patients with chronic lymphocytic leukaemia who do not achieve minimal residual disease negative disease state following chemoimmunotherapy approaches. The toxicity seems to be acceptable considering the poor prognosis of the eligible patients. The trial independently confirms the clinical significance of a novel, minimal residual disease-based algorithm to predict short progression-free survival, which might be incorporated in future clinical trials to identify candidates for additional maintenance treatment.

FUNDING

Celgene Corporation.

Chronic lymphocytic leukemia: 2017 update on diagnosis, risk stratification, and treatment

DISEASE OVERVIEW

Chronic lymphocytic leukemia (CLL) is the commonest leukemia in western countries. The disease typically occurs in elderly patients and has a highly variable clinical course. Leukemic transformation is initiated by specific genomic alterations that impair apoptosis of clonal B cells.

DIAGNOSIS

The diagnosis is established by blood counts, blood smears, and immunophenotyping of circulating B lymphocytes, which identify a clonal B-cell population carrying the CD5 antigen and B-cell markers.

PROGNOSIS

Two prognostic staging systems exist, the Rai and Binet staging systems, which are established by physical examination and blood counts. Various biological and genetic markers also have prognostic value. Deletions of the short arm of chromosome 17 (del(17p)) and/or mutations of the TP53 gene predict resistance to available chemotherapies. A comprehensive prognostic score (CLL-IPI) using genetic, biological, and clinical variables has recently been developed allowing to classify CLL into very distinct risk groups.

THERAPY

Patients with active or symptomatic disease or with advanced Binet or Rai stages require therapy. For physically fit patients, chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab remains the current standard therapy. For unfit patients, currently available evidence supports two options for a first-line therapy: chlorambucil combined with an anti-CD20 antibody (obinutuzumab or rituximab or ofatumumab) or a continuous therapy with ibrutinib. At relapse, the initial treatment may be repeated, if the treatment-free interval exceeds 3 years. If the disease relapses earlier, therapy should be changed using alternative agents such as bendamustine (plus rituximab), alemtuzumab, lenalidomide, ofatumumab, ibrutinib, idelalisib, or venetoclax. Patients with a del(17p) or TP53 mutation can be treated with ibrutinib, venetoclax, or a combination of idelalisib and rituximab. An allogeneic SCT may be considered in relapsing patients with TP53 mutations or del(17p) or patients that are refractory to chemoimmunotherapy and the novel inhibitors.

FUTURE CHALLENGES

The new agents (ibrutinib, idelalisib, venetoclax, and obinutuzumab) hold the potential to significantly improve the outcome of CLL patients. However, their optimal use (in terms of combination, sequence, and duration) remains unknown. Therefore, CLL patients should be treated in clinical trials whenever possible.

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.

High-Throughput Immunogenetics for Clinical and Research Applications in Immunohematology: Potential and Challenges

Analysis and interpretation of Ig and TCR gene rearrangements in the conventional, low-throughput way have their limitations in terms of resolution, coverage, and biases. With the advent of high-throughput, next-generation sequencing (NGS) technologies, a deeper analysis of Ig and/or TCR (IG/TR) gene rearrangements is now within reach, which impacts on all main applications of IG/TR immunogenetic analysis. To bridge the generation gap from low- to high-throughput analysis, the EuroClonality-NGS Consortium has been formed, with the main objectives to develop, standardize, and validate the entire workflow of IG/TR NGS assays for 1) clonality assessment, 2) minimal residual disease detection, and 3) repertoire analysis. This concerns the preanalytical (sample preparation, target choice), analytical (amplification, NGS), and postanalytical (immunoinformatics) phases. Here we critically discuss pitfalls and challenges of IG/TR NGS methodology and its applications in hemato-oncology and immunology.

Milestones in Chronic Lymphocytic Leukemia: An exciting decade of progress-10th anniversary of memo

The past 10 years have been an exciting ride for Chronic Lymphocytic Leukemia (CLL) aficionados. An overview of changes in management paradigms in CLL, ranging from insights into biology, via chemotherapy and chemoimmunotherapy to maintenance and novel drugs will be presented.

Active CMV infection in two patients with multiple sclerosis treated with alemtuzumab

Alemtuzumab is a humanized monoclonal antibody targeting the surface molecule CD52, resulting in a rapid depletion of innate and adaptive immune cells. Infection rates in multiple sclerosis (MS) treatment trials were higher in alemtuzumab than in interferon beta–treated patients. We report two MS patients who developed cytomegalovirus disease within 1 month after the first 5-day cycle of alemtuzumab. Upon identification and appropriate treatment of the infection, each recovered completely. Neurologists should be aware of this serious but treatable complication.

Flow cytometry minimal residual disease after allogeneic transplant for chronic lymphocytic leukemia

OBJECTIVES

This study investigates whether achieving complete remission (CR) with undetectable minimal residual disease (MRD) after allogeneic stem cell transplantation (allo-SCT) for chronic lymphocytic leukemia (CLL) affects outcome.

METHODS

We retrospectively studied 46 patients transplanted for CLL and evaluated for post-transplant MRD by flow cytometry.

RESULTS

At transplant time, 43% of the patients were in CR, including one with undetectable MRD, 46% were in partial response, and 11% had refractory disease. After transplant, 61% of the patients achieved CR with undetectable MRD status. By multivariate analysis, reaching CR with undetectable MRD 12 months after transplant was the only factor associated with better progression-free survival (P = 0.02) and attaining undetectable MRD, independently of the time of negativity, was the only factor that correlated with better overall survival (P = 0.04).

CONCLUSION

Thus, achieving undetectable MRD status after allo-SCT for CLL is a major goal to improve post-transplant outcome.

Chemoimmunotherapy Versus Targeted Treatment in Chronic Lymphocytic Leukemia: When, How Long, How Much, and in Which Combination?

During the past 5 years, rapid therapeutic advances have changed the landscape of chronic lymphocytic leukemia (CLL) therapy. This disease has traditionally been treated using cytotoxic chemotherapy regimens in combination with anti-CD20 antibody treatment, and recent long-term follow-up data from multiple centers suggest that fit patients with CLL with favorable disease features-particularly mutated immunoglobulin heavy chain variable region (IGHV) genes-derive very long-term benefit from the most potent of these regimens, namely the fludarabine, cyclophosphamide, and rituximab (FCR) regimen. The advent of oral targeted therapies, particularly ibrutinib and idelalisib, has provided generally well-tolerated and highly effective additional options that have come into widespread use in the relapsed setting. Additional agents are advancing in clinical development, with the BCL-2 inhibitor venetoclax likely to be approved by the U.S. Food and Drug Administration (FDA) in 2016. With the development of these novel therapies for patients with relapsed CLL, many unanswered questions remain, including the optimal sequence (first vs. second line), duration, discontinuation, and combination of these agents. In addition, recent publications show the emergence of a pattern of treatment resistance in certain subgroups of patients with del(17p) and complex karyotype that needs further study and improvement. Because the field of CLL management has become much more complex, we focus here on understanding the recent data and discuss many of the questions and controversies important for how we approach patients with CLL.

Minimal residual disease is an independent predictor for 10-year survival in CLL

MRD negativity is a predictor for long-term progression-free and overall survival independent of the type and line of therapy. MRD negativity confers the greatest prognostic benefit when achieved in the frontline setting.

Prognostication of chronic lymphocytic leukemia in the era of new agents

The prognosis of chronic lymphocytic leukemia (CLL) is very heterogeneous. Therefore, a plethora of prognostic factors has been identified to allow a better prediction of the individual prognosis of a given patient. The clinical staging systems by Rai and Binet have been the backbone of clinical management for several decades. The advent of genetic and biochemical markers, as well as next-generation sequencing has provided several markers that can predict the prognosis of patients with CLL. Using this knowledge, several scores have been created to improve predicting overall survival and/or treatment-free survival. These prognostic scores were developed in the era of chemotherpay/chemoimmunotherapy. Therefore, they now need to be tested with novel agents. However, despite tremendously improved therapeutic options, CLL patients with TP53 dysfunction or a complex karyotype remain at very high risk and seem to have a shorter (treatment-free) survival. The recently published international prognostic index (CLL IPI) incorporates most of these factors and provides a tool to analyze outcome in the modern era of targeted therapies.

Alemtuzumab consolidation in chronic lymphocytic leukaemia: a phase I/II multicentre trial

OBJECTIVE

Despite high rates of long-lasting remissions in patients with chronic lymphocytic leukaemia (CLL) treated with chemoimmunotherapy, none of the current therapeutic approaches is curative with the exception of allogeneic transplantation. One strategy to extend progression-free survival and long-term survival might be the establishment of consolidation therapies.

METHODS

In this trial, patients with complete or partial second remission after fludarabine-based treatment received consolidation therapy with alemtuzumab. The aim of this phase I/II trial was to determine the maximal tolerable dose (MTD) of alemtuzumab consolidation and to evaluate safety and efficacy in patients who responded to second-line fludarabine-based treatment. Thirteen patients in complete (CR) or partial remission (PR) received alemtuzumab dose escalation starting with 10 mg intravenously (iv) once weekly for 8 wk and increasing in 10-mg intervals per dose level.

RESULTS

The main dose-limiting toxicities (DLTs) were infectious complications, and the MTD was determined at 10 mg. After alemtuzumab consolidation, seven of 13 patients (53%) were in CR, and four of these patients (30.7%) achieved minimal residual disease (MRD) negativity (<1 × 10E-4). At a median follow-up of 71.5 months, four patients were progression-free, with a median progression-free survival (PFS) of 28.5 months after the end of second-line treatment.

CONCLUSION

The results provide a safe and efficient schedule with weekly intravenous application of 10 mg of alemtuzumab as a consolidation regime in patients with CLL.

Rituximab maintenance versus observation alone in patients with chronic lymphocytic leukaemia who respond to first-line or second-line rituximab-containing chemoimmunotherapy: final results of the AGMT CLL-8a Mabtenance randomised trial

BACKGROUND

In many patients with chronic lymphocytic leukaemia requiring treatment, induction therapy with rituximab plus chemotherapy improves outcomes compared with chemotherapy alone. In this study we aimed to investigate the potential of rituximab maintenance therapy to prolong disease control in patients who respond to rituximab-containing induction regimens.

METHODS

In this randomised, international, multicentre, open-label, phase 3 clinical trial, we enrolled patients who had achieved a complete response (CR), CR with incomplete bone marrow recovery (CRi), or partial response (PR) to first-line or second-line rituximab-containing chemoimmunotherapy and randomly assigned them in a 1:1 ratio (central block randomisation in the electronic case report form system) to either intravenous rituximab 375 mg/m(2) every 3 months, or observation alone, for 2 years. Stratification was by country, line of treatment, type of chemotherapy added to the rituximab backbone, and degree of remission following induction. The primary endpoint was progression-free survival. Efficacy analysis was done in the intention-to-treat population. This is the final, event-triggered analysis. Final analysis was triggered by the occurrence of 92 events. This trial is registered with ClinicalTrials.gov, number NCT01118234.

FINDINGS

Between April 1, 2010, and Dec 23, 2013, 134 patients were randomised to rituximab and 129 to observation alone. Median observation times were 33·4 months (IQR 25·7-42·8) for the rituximab group and 34·0 months (25·4-41·9) for the observation group. Progression-free survival was significantly longer in the rituximab maintenance group (47·0 months, IQR 28·5-incalculable) than with observation alone (35·5 months, 95% CI 25·7-46·3; hazard ratio [HR] 0·50, 95% CI 0·33-0·75, p=0·00077). The incidence of grade 3-4 haematological toxicities other than neutropenia was similar in the two treatment groups. Grade 3-4 neutropenia occurred in 28 (21%) patients in the rituximab group and 14 (11%) patients in the observation group. Apart from neutropenia, the most common grade 3-4 adverse events were upper (five vs one [1%] patient in the observation group) and lower (three [2%] vs one [1%]) respiratory tract infection, pneumonia (nine [7%] vs two [2%]), thrombopenia (four [3%] vs four [3%]), neoplasms (five [4%] vs four [3%]), and eye disorders (four [3%] vs two [2%]). The overall incidence of infections of all grades was higher among rituximab recipients (88 [66%] vs 65 [50%]).

INTERPRETATION

Rituximab maintenance therapy prolongs progression-free survival in patients achieving at least a PR to induction with rituximab plus chemotherapy, and the treatment is well tolerated overall. Although it is associated with an increase in infections, there is no excess in infection mortality, suggesting that remission maintenance with rituximab is an effective and safe option in the management of chronic lymphocytic leukaemia in early treatment phases.

FUNDING

Arbeitsgemeinschaft Medikamentöse Tumortherapie gemeinnützige GmbH (AGMT), Roche.

Bone Marrow Synoptic Reporting for Hematologic Neoplasms: Guideline From the College of American Pathologists Pathology and Laboratory Quality Center

CONTEXT

-There is ample evidence from the solid tumor literature that synoptic reporting improves accuracy and completeness of relevant data. No evidence-based guidelines currently exist for synoptic reporting for bone marrow samples.

OBJECTIVE

-To develop evidence-based recommendations to standardize the basic components of a synoptic report template for bone marrow samples.

DESIGN

-The College of American Pathologists Pathology and Laboratory Quality Center convened a panel of experts in hematopathology to develop recommendations. A systematic evidence review was conducted to address 5 key questions. Recommendations were derived from strength of evidence, open comment feedback, and expert panel consensus.

RESULTS

-Nine guideline statements were established to provide pathology laboratories with a framework by which to develop synoptic reporting templates for bone marrow samples. The guideline calls for specific data groups in the synoptic section of the pathology report; provides a list of evidence-based parameters for key, pertinent elements; and addresses ancillary testing.

CONCLUSION

-A framework for bone marrow synoptic reporting will improve completeness of the final report in a manner that is clear, succinct, and consistent among institutions.

Initial therapy of chronic lymphocytic leukemia

Only chronic lymphocytic leukemia (CLL) patients with active or symptomatic disease or with advanced Binet or Rai stages require therapy. Prognostic risk factor profile and comorbidity burden are most relevant for the choice of treatment. For physically fit patients, chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab remains the current standard therapy. For unfit patients, treatment with an anti-CD20 antibody (obinutuzumab or rituximab or ofatumumab) plus milder chemotherapy (chlorambucil) may be applied. Patients with a del(17p) or TP53 mutation should be treated with the kinase inhibitors ibrutinib or a combination of idelalisib and rituximab. Clinical trials over the next several years will determine, whether kinase inhibitors, other small molecules, immunotherapeutics, or combinations thereof will further improve outcomes for patients with CLL.

A complementary role of multiparameter flow cytometry and high-throughput sequencing for minimal residual disease detection in chronic lymphocytic leukemia: an European Research Initiative on CLL study

In chronic lymphocytic leukemia (CLL) the level of minimal residual disease (MRD) after therapy is an independent predictor of outcome. Given the increasing number of new agents being explored for CLL therapy, using MRD as a surrogate could greatly reduce the time necessary to assess their efficacy. In this European Research Initiative on CLL (ERIC) project we have identified and validated a flow-cytometric approach to reliably quantitate CLL cells to the level of 0.0010% (10⁻⁵). The assay comprises a core panel of six markers (i.e. CD19, CD20, CD5, CD43, CD79b and CD81) with a component specification independent of instrument and reagents, which can be locally re-validated using normal peripheral blood. This method is directly comparable to previous ERIC-designed assays and also provides a backbone for investigation of new markers. A parallel analysis of high-throughput sequencing using the ClonoSEQ assay showed good concordance with flow cytometry results at the 0.010% (10⁻⁴) level, the MRD threshold defined in the 2008 International Workshop on CLL guidelines, but it also provides good linearity to a detection limit of 1 in a million (10⁻⁶). The combination of both technologies would permit a highly sensitive approach to MRD detection while providing a reproducible and broadly accessible method to quantify residual disease and optimize treatment in CLL.