Delayed-onset peripheral blood cytopenia after rituximab: frequency and risk factor assessment in a consecutive series of 77 treatments

Hypogammaglobulinemia, late-onset neutropenia, and infections following rituximab

Rituximab is a chimeric anti-CD20 monoclonal antibody that targets CD20-expressing B lymphocytes, has a well-defined efficacy and safety profile, and is broadly used to treat a wide array of diseases. In this review, we cover the mechanism of action of rituximab and focus on hypogammaglobulinemia and late-onset neutropenia-2 immune effects secondary to rituximab-and subsequent infection. We review risk factors and highlight key considerations for immunologic monitoring and clinical management of rituximab-induced secondary immune deficiencies. In patients treated with rituximab, monitoring for hypogammaglobulinemia and infections may help to identify the subset of patients at high risk for developing poor B cell reconstitution, subsequent infections, and adverse complications. These patients may benefit from early interventions such as vaccination, antibacterial prophylaxis, and immunoglobulin replacement therapy. Systematic evaluation of immunoglobulin levels and peripheral B cell counts by flow cytometry, both at baseline and periodically after therapy, is recommended for monitoring. In addition, in those patients with prolonged hypogammaglobulinemia and increased infections after rituximab use, immunologic evaluation for inborn errors of immunity may be warranted to further risk stratification, increase monitoring, and assist in therapeutic decision-making. As the immunologic effects of rituximab are further elucidated, personalized approaches to minimize the risk of adverse reactions while maximizing benefit will allow for improved care of patients with decreased morbidity and mortality.

Impact of Rituximab and Corticosteroids on Late Cytopenias Post-Chimeric Antigen Receptor T Cell Therapy

Chimeric antigen receptor (CAR) T cell therapy represents a significant advancement in the treatment of patients with relapsed/refractory B cell lymphoid malignancies. Cytokine release syndrome and immune effector cell-associated neurotoxicity represent the most acute serious adverse events post CAR T cell therapy but the occurrence and persistence of cytopenias post CAR T cell therapy represent a significant adverse event and a management challenge. While most patients typically recover blood counts by 30 days, a significant subset of patients have persistent or late cytopenias beyond 30 days. Patients receiving CAR T cell are heavily pre-treated and the impact of prior therapies on late cytopenias is not well understood. In this study, we found an association between increased number of rituximab infusions and/or cumulative rituximab dose received prior to CAR T cell infusion and persistent anemia and thrombocytopenia at 90 and 180 days afterwards. An overall increased number of prior lines of therapy was also associated with persistent lymphopenia and anemia at 90 days while receiving a prior autologous hematopoietic cell transplant was associated with a greater risk of neutropenia and lymphopenia.

Late-onset toxicities of monoclonal antibodies in cancer patients

Cancer therapy duration is variable and may take years, adding a new challenge of maintaining the best life quality for cancer survivors. In cancer patients, late-onset toxicities have been reported with monoclonal antibodies and may involve several body organs or systems. They are defined as an autoimmune illnesses that can happen months to years after treatment discontinuation. Late-onset toxicities have become a focus of clinical care and related research. After cancer therapy is completed, the patient should receive longitudinal follow-up to detect these late effects as early as possible. The current review summarizes the recently reported late-onset toxicities of four classes of monoclonal antibodies (anti-CD52, anti-CTLA-4, anti-PD-1 and anti-CD20) with guidance for the diagnostic tools, appropriate management and treatment.

Immune- and Non-Immune-Mediated Adverse Effects of Monoclonal Antibody Therapy: A Survey of 110 Approved Antibodies

Identification of new disease-associated biomarkers; specific targeting of such markers by monoclonal antibodies (mAbs); and application of advances in recombinant technology, including the production of humanized and fully human antibodies, has enabled many improved treatment outcomes and successful new biological treatments of some diseases previously neglected or with poor prognoses. Of the 110 mAbs preparations currently approved by the FDA and/or EMA, 46 (including 13 antibody–drug conjugates) recognizing 29 different targets are indicated for the treatment of cancers, and 66, recognizing 48 different targets, are indicated for non-cancer disorders. Despite their specific targeting with the expected accompanying reduced collateral damage for normal healthy non-involved cells, mAbs, may cause types I (anaphylaxis, urticaria), II (e.g., hemolytic anemia, possibly early-onset neutropenia), III (serum sickness, pneumonitis), and IV (Stevens–Johnson syndrome, toxic epidermal necrolysis) hypersensitivities as well as other cutaneous, pulmonary, cardiac, and liver adverse events. MAbs can provoke severe infusion reactions that resemble anaphylaxis and induce a number of systemic, potentially life-threatening syndromes with low frequency. A common feature of most of these syndromes is the release of a cascade of cytokines associated with inflammatory and immunological processes. Epidermal growth factor receptor-targeted antibodies may provoke papulopustular and mucocutaneous eruptions that are not immune-mediated.

Intensive Safety Monitoring of Rituximab (Biosimilar Novex® and the Innovator) in Pediatric Patients With Complex Diseases

Although rituximab is widely used off-label for complex pediatric diseases, safety reports are limited. We aimed to report evidence of its use in clinical practice, to describe the incidence of adverse drug reactions (ADR) to rituximab biosimilar Novex^® and innovator, and to identify risk factors for the development of ADR in a real-life follow-up cohort of pediatric patients with complex diseases. We conducted a prospective, longitudinal, observational, single-centre study in patients that received rituximab for any complex disease, and as part of an intensive pharmacovigilance program. Demographic, pharmacological, clinical, and drug-related data were collected for all patients. ADR-free survival, including infusion-related reactions (IRR) and delayed ADR (dADR), was estimated using Kaplan-Meier curves. Risk factors were evaluated by multivariable Cox regression models. In total, 77 patients (<19 y.o.) received 187 infusions of rituximab Novex^® (n = 155) or innovator rituximab (n = 32) for neurologic (Neu), immune-hematologic-rheumatic (IHR), oncologic (O) diseases, and hematopoietic stem-cell transplantation (HSCT) or solid-organ transplantation (SOT). We recorded 29 IRR and 58 dADR that occurred in 27 (35.1%) and 29 (37.7%) patients, respectively. The respiratory tract was the most affected during IRR (29.6%) and hypogammaglobulinemia (37.9 %) was the most frequent dADR. First versus subsequent infusions (HR 5.4, CI95% 2.4-12.1, p<0.05), sex (boys vs. girls, HR 0.3, CI95% 0.1-0.8, and p<0.05), and diagnosis (Neu-IHR diseases vs. O-HSCT-SOT, HR 2.3, CI95% 1.02-5.4, and p < 0.05) were significantly associated with the development of IRR. For dADR, risk factors were diagnosis (Neu-IHR diseases vs. O-HSCT-SOT, HR 0.4, CI95% 0.2-0.9, and p < 0.05) and cumulative body surface area-normalized dosage (HR 1.0003, CI95% 1.0001-1.0006, and p < 0.05). The present is the largest real-world safety assessment of rituximab in Latin-American children with complex diseases supporting its use based on the overall acceptable safety. Identification of risk factors may contribute to optimization of off-label rituximab treatment in pediatrics.

Ocrelizumab associated late-onset neutropenia in the patient with multiple sclerosis: Case report and literature review

Introduction. Ocrelizumab is a recombinant humanized monoclonal antibody that selectively depletes CD20-expressing B cells, which is approved for the treatment of the relapsing and primary progressive multiple sclerosis (MS). It is extremely rarely associated with late onset neutropenia (LON), as an adverse event. Case Outline. We describe a case, from the Treatment Registry of the Clinic of Neurology, University Clinical Center of Serbia, Belgrade, of a transient, asymptomatic, LON which was detected in a na?ve relapsing-remitting MS patient, six-months after treatment with ocrelizumab. Conclusion. Having in mind all until now available data, which indicate that rarely occurring LON on ocrelizumab is asymptomatic and transient in the majority of cases, we assume that it may be suggested that only in patients with complaints suggesting the presence of possible infection, additional complete blood count monitoring, should be mandatory, exclusively at that moment, apart from the precisely defined regular follow-up.

Late onset neutropenia after rituximab and obinutuzumab treatment - characteristics of a class-effect toxicity

Late onset neutropenia (LON) after rituximab is a previously described complication. We aimed to assess and characterize LON after obinutuzumab, a novel anti-CD20 antibody, in the real-world setting and compare it to LON after rituximab therapy. We retrospectively analyzed 330 consecutive patients with lymphoproliferative neoplasms (rituximab-treated n = 283; obinutuzumab-treated n = 47). LON occurred in 23% patients with similar incidence in rituximab (n = 66, 23%) or obinutuzumab (n = 10, 21%) groups (p = 0.853). Patients treated for CLL and post-transplantation lymphoproliferative disease (PTLD) were at higher risk to develop LON (multivariate analysis: HR for CLL - 6.62 CI 95% 1.33-32.92; HR for PTLD 15.82 CI 95% 2.04-122.4). Febrile neutropenia was uncommon during LON and occurred in 15 patients (4.5%; rituximab (n = 14) and obinutuzumab (n = 1).These data suggest that LON after obinutuzumab treatment is as common as with rituximab. The similarities in LON after rituximab and obinutuzumab argue for a possible class effect for anti-CD20 monoclonal antibodies.

Dysfunctional Immune System Reconstitution After Rituximab Exposure In Utero

Rituximab is an antibody that binds to B-lymphocytes and is increasingly used during pregnancy. As an immunoglobulin G, it will transfer across the placenta. Previous case reports describe a diversity of clinical presentations in neonates born following rituximab exposure in utero. Our case is the first to offer the long-term experience in the care of an infant with severe neutropenia and prolonged profound hypogammaglobulinemia and class-switching B cell defect after in utero rituximab exposure.

The clinical efficacy of Rituximab administration in autoimmunity disorders, primary immunodeficiency diseases and malignancies

Rituximab (RTX), as a monoclonal antibody-based immunotherapeutic intervention targeting CD20 on B cells, has proven efficacy in the treatment of patients with some immune-mediated diseases. In the present review, we provided information on the immunobiological mechanisms of signaling for RTX and its clinical applications, according to the immune-pathophysiology involved in the microenvironment of multiple diseases. We highlighted combination therapy, dose schedules, and laboratory monitoring, as well as the associated common and rare side effects to avoid. We also discussed the efficacy and safety of RTX-based therapeutic strategies and whether RTX therapy can be used as a promising treatment regimen for autoimmune diseases, primary immunodeficiency diseases, and malignancies. Our review highlights and supports the importance of collaboration between basic medical researchers and clinical specialists when considering the use of RTX in the treatment of various immune-mediated disorders.

Rituximab-induced acute thrombocytopenia in patients with splenomegaly B Cell lymphoma: an underdiagnosed but severe complication

Rituximab is popularly used in the treatment of B-cell lymphomas that bear CD20 antigen. Most of the adverse events (AEs) induced by rituximab are infusion-related symptoms. However, rituximab-induced acute thrombocytopenia (RIAT), which often develops within the 1-3 days after rituximab administration, is relatively unusual, severe, and usually self-recovering. Until now, most of the reports about RIAT were described as case reports and RIAT often occurred in patients with mantle cell lymphoma (MCL). Here, we report two patients who developed severe RIAT, one patient had a refractory and relapsed follicular lymphoma (FL), and the other patient was newly diagnosed with splenic marginal zone lymphoma (SMZL). RIAT is a rare, under-diagnosed but serious adverse event that should arouse attention to clinicians, and routine blood count monitoring should be considered after the administration of rituximab, especially for high-risk lymphoma patients or patient with splenomegaly.

Cold Agglutinin Disease and Autoimmune Hemolytic Anemia with Pulmonary Embolism as a Presentation of COVID-19 Infection

BACKGROUND

Lymphopenia, thrombocytopenia, and elevated D-dimer and ferritin levels are frequently reported in patients with severe coronavirus disease 2019 (COVID-19). Here we report a case of cold agglutinin disease (CAD), autoimmune hemolytic anemia (AIHA), and pulmonary embolism as a presentation of COVID-19 infection.

CASE REPORT

A 51-year-old African-American woman presented to the emergency room with fever and shortness of breath. She was tachycardic, febrile, and had an oxygen saturation of 88% on room air. Laboratory studies showed hemoglobin (Hb) 5.1 g/dL, D-dimer 4.55 μg/mL, and C-reactive protein 12.3 mg/dL. Computed tomography scan of the chest showed acute pulmonary embolism involving the bilateral lower lobe segmental branches. Her influenza test was negative, but her SARS-CoV-2 test returned positive. Due to severe anemia, she was not started on any anticoagulation. Haptoglobin was low. Direct antiglobulin test returned positive for anticomplement and negative for anti-immunoglobulin G. Cold agglutinin titer was 80. Mycoplasma, Epstein-Barr virus, parvovirus, human immunodeficiency viruses, and acute hepatitis screen were negative. Abdominal and pelvic computed tomography showed a normal liver and spleen without lymphadenopathy. Peripheral blood smear showed red blood cell agglutination. On Day 2, she became hypoxic requiring 6 L oxygen. Since her Hb remained stable, she was started on low-intensity unfractionated heparin. Inflammatory markers subsequently improved and she was weaned off oxygen. Her Hb remained stable at 9 g/dL and she was discharged home. After 2 weeks, her Hb increased to 11 g/dL.

CONCLUSION

As exemplified in this case report, COVID-19 infection can lead to thromboembolism, CAD, and AIHA and it should be recognized as a potential etiology to such rare diseases.

Rituximab in autoimmune pemphigoid diseases: Indications, optimized regimens, and practice gaps

Rituximab is a monoclonal antibody targeting CD20 on B cells with proven efficacy for pemphigus vulgaris, now an FDA-approved indication. Other autoimmune bullous diseases can be challenging to treat and have significant associated morbidity and mortality, but data supporting the use of rituximab in pemphigoid group diseases remain limited. Although rituximab demonstrates efficacy for clinical improvement and remission in pemphigoid, concern for adverse events may also limit the use of this medication. We review the current evidence fo rthe use of rituximab in pemphigoid diseases, pertinent dosing schedules and laboratory monitoring, and the associated common and rare adverse events. Review of the literature to date not only supports consideration of rituximab for treatment of refractory pemphigoid group diseases but also reflects tolerability and an acceptable safety profile.

Infection risks of rituximab versus non-rituximab treatment for rheumatoid arthritis: A systematic review and meta-analysis

OBJECTIVE

The aim of this study was to assess the differences in infection rates between rituximab (RTX) and non-RTX treatment in patients with rheumatoid arthritis (RA).

METHODS

A systematic review and meta-analysis was conducted by searching databases of PubMed, MEDLINE, EMBASE, Web of Science and Cochrane Library through to June 2018. We included studies that compared RTX and non-RTX treatment for patients with RA. Outcome measures were overall infections and serious infections between RTX and non-RTX treatments.

RESULTS

A total of 11 articles, including 9502 patients (4595 with RTX treatment and 4907 with non-RTX treatment) met our inclusion criteria. The results demonstrated that RTX-related all infections and serious infections in RA patients were 43.8% and 4.4%, respectively. Pooled analysis showed no significant differences between RTX and non-RTX treatment groups in overall infections rate (43.3% vs 44.9%; odds ratio [OR] = 0.87; 95% CI = 0.70-1.08) and serious infections rate (4.1% vs 4.6%; OR = 1.05; 95% CI = 0.84-1.31). Subgroup analysis also showed no significant differences in overall infections between RTX versus placebo (OR = 0.98, 95% CI = 0.71-1.33); RTX versus tumor necrosis factor inhibitors (TNFi) (OR = 0.47, 95% CI = 0.30-1.73); RTX plus methotrexate (MTX) versus placebo plus MTX (OR = 0.98, 95% CI = 0.77-1.24), and in serious infections between RTX versus placebo (OR = 1.06, 95% CI = 0.36-3.07); RTX versus TNFi (OR = 1.25, 95% CI = 0.96-1.63); RTX plus MTX versus placebo plus MTX (OR = 0.69, 95% CI = 0.39-1.20).

CONCLUSION

In patients with RA, RTX treatment has no additional risks for infections over non-RTX treatment.

Late-Onset Neutropenia after Rituximab Treatment for Adult-Onset Nephrotic Syndrome

A 41-year-old woman developed nephrotic syndrome at the age of 32 and was diagnosed with minimal change nephrotic syndrome based on a renal biopsy. Although remission was achieved with administration of prednisolone (PSL) and cyclosporine, the nephrotic syndrome recurred. She was also started on rituximab (RTX). She developed late-onset neutropenia after RTX treatment (R-LON) and improved 17 days later. Although the majority of R-LON cases undergo spontaneous remission, cases of death have been reported. This report is intended to warn about R-LON, since the use of RTX for adult-onset nephrotic syndrome is expected to increase in the future.

Chronic Benign CD8+ Proliferation: A Rare Affection that Can Mimic a Lymphoma Relapse

Chronic benign CD8+ proliferation is a rare syndrome that can take the form of a variety of other diseases. Peripheral adenopathy, cytopenia, and infiltration of the liver, kidneys, bowels, or other organs are the most common clinical presentations of the syndrome. CD8+ expansion can be clonal and nonclonal. It generally occurs in patients with innate or acquired immunodeficiency (HIV+) or in patients receiving immunosuppressive therapy. It has been found repeatedly in patients who developed severe hypogammaglobulinemia after treatment with rituximab. Diagnosis of the disease can be difficult because it can mimic relapse of a lymphoma, and a common biopsy examination cannot identify the problem at first. The authors describe a case of a patient pretreated with rituximab who developed agammaglobulinemia and peripheral adenopathy. Biopsy of an enlarged lymph node showed "reactive lymphadenitis." Additionally, a flow-cytometric examination revealed a pathological population of CD8+ lymphocytes. The treatment, which differed from treatments of lymphoma relapse, consisted of corticosteroids and IVIG substitutions and has led to a regression of clinical symptoms. With more frequent usage of rituximab, one can expect increased occurrence of a very rare CD8+ expansion that can reliably emulate the relapse of a lymphoma.

Drug-Induced Hematological Cytopenia in Kidney Transplantation and the Challenges It Poses for Kidney Transplant Physicians

Drug-induced hematological cytopenia is common in kidney transplantation. Various cytopenia including leucopenia (neutropenia), thrombocytopenia, and anemia can occur in kidney transplant recipients. Persistent severe leucopenia or neutropenia can lead to opportunistic infections of various etiologies. On the contrary, reducing or stopping immunosuppressive medications in these events can provoke a rejection. Transplant clinicians are often faced with the delicate dilemma of balancing cytopenia and rejection from adjustments of immunosuppressive regimen. Differentials of drug-induced cytopenia are wide. Identification of culprit medication and subsequent modification is also challenging. In this review, we will discuss individual drug implicated in causing cytopenia and correlate it with corresponding literature evidence.

Secondary Hypogammaglobulinemia After Rituximab for Neuromyelitis Optica: A Case Report

A 17-year-old male with history of neuromyelitis optica and seizures presented to the pulmonology clinic for evaluation of recurrent pneumonias. He had received rituximab for the past 6 years. Over the past 2 years, he experienced four episodes of pneumonia. In between these episodes, he would improve briefly but continued to have daily cough that was productive with yellow phlegm. He also had recurrent rhinitis and sinusitis despite multiple antibiotic courses. Review of chest X-rays revealed localized right middle lobe and right lower lobe infiltrates. An extensive workup was performed, including computed tomography (CT) of the chest and bronchoscopy to rule out congenital lesions of the right lung and foreign body aspiration. Chest CT showed right lower lobe bronchiectasis. Flexible bronchoscopy with bronchoalveolar lavage showed normal anatomy with thick mucus secretions in the right lower lobe. Immunologic evaluation was performed and revealed low levels of immunoglobulin (Ig)-G, IgM, and IgA, which had declined since initiation of rituximab. Lymphocyte subset testing was remarkable for low cluster of differentiation (CD)-19. He was referred to allergy and immunology and was initiated on immunoglobulin-replacement therapy (IGRT) for acquired hypogammaglobulinemia secondary to rituximab. There was marked clinical improvement after initiation of IGRT.

Consequences of B-cell-depleting therapy: hypogammaglobulinemia and impaired B-cell reconstitution

Rituximab is a chimeric monoclonal antibody used to treat hematologic and autoimmune diseases by depleting CD20-expressing B cells. Patients may develop hypogammaglobulinemia following treatment, with some demonstrating failure of B-cell recovery. The true frequency of hypogammaglobulinemia and/or impaired B-cell reconstitution post rituximab is unknown due to the lack of prospective studies in different patient cohorts. The clinical significance remains controversial; some patients have recurrent infections while others are relatively asymptomatic. The aim of this review is to describe the prevalence of hypogammaglobulinemia and the associated risk for developing severe infection, in patients with differing underlying clinical conditions treated with rituximab. This may facilitate classification and prognostication of patients who develop these conditions and identify patients who may be at high risk of developing these complications, including those who may benefit from immunoglobulin replacement therapy.

B cells facilitate platelet production mediated by cytokines in patients with essential thrombocythaemia

We investigated the role of activated B cells in thrombopoiesis through the production of interleukin (IL)-1beta and IL-6 in patients with essential thrombocythaemia. The number of B cells did not differ between essential thrombocythaemia patients, irrespective of the presence of Janus activated kinase-2 V617F mutation or wild type, and age-matched healthy adults. However, the number of IL-1beta/IL- 6-producing B cells was significantly higher in essential thrombocythaemia patients than that in healthy controls. The relatively high level of IL-1beta/IL-6 production by B cells was associated with serum B cell-activating factor and expression of Toll-like receptor 4 on B cells. A high level of B cell-activating factor was present in essential thrombocythaemia patients with both Janus activated kinase-2 genotypes. Incubation with B cell-activating factor enhanced the expression of Toll-like receptor 4 on B cells. IL-1beta and IL-6 production was not stimulated by B cell-activating factor alone; Toll-like receptor 4 was activated by lipopolysaccharide or patients’ sera to produce IL-1beta and IL-6 in B cells. Moreover, essential thrombocythaemia patient B cells facilitated megakaryocyte differentiation when co-cultured with CD34+ haematopoietic stem cells. Antibody neutralisation of IL-1beta and IL-6 attenuated megakaryocyte differentiation. These data suggest that B cells play a crucial role in thrombopoiesis in essential thrombocythaemia patients.

Risk factors predisposing to the development of hypogammaglobulinemia and infections post-Rituximab

Rituximab (RTX) is a monoclonal antibody against CD20, commonly used in the treatment of hematological malignancies and autoimmune diseases. The use of RTX is related to the development of hypogammaglobulinemia and infections. Aim of this review is to summarize the evidence supporting the association of specific risk factors with the development of hypogammaglobulinemia and infections post-RTX. Immunological complications are more common in patients with malignant diseases as compared to non-malignant diseases. Moreover, the use of more than one dose of RTX, maintenance regimens, low pre-treatment basal immunoglobulin levels and the association with Mycophenolate and purine analogues represent risk factors for the development of hypogammaglobulinemia. The number of RTX courses, the evidence of low IgG levels for more than 6 months, the use of G-CSF, the occurrence of chronic lung disease, cardiac insufficiency, extra-articular involvement in patients with rheumatoid arthritis, low levels of IgG and older age have been correlated with a higher risk of infections. Even though the heterogeneity of the studies in terms of study population age and underlying disease, RTX schedules as well as differences in pre-treatment or concomitant therapy doesn't allow drawing definitive conclusions, the study of the literature highlight the association of specific risk factors with the occurrence of hypogammaglobulinemia and/or infections. A long term randomized controlled clinical trial could be useful to define a personalized evidence-based risk management plan for patients treated with RTX.

Incidence of late onset neutropenia associated with rituximab use in B cell lymphoma patients undergoing autologous stem cell transplantation

Reversible late onset neutropenia associated with rituximab has been reported with incidence rates varying from 15 to 70% in B cell lymphoma patients receiving autologous stem cell transplantation. We conducted a retrospective descriptive study at one tertiary care center in adult B cell lymphoma patients treated with rituximab and autologous stem cell transplantation between 1 January 2004 and 30 June 2014. Late onset neutropenia was defined as an absolute neutrophil count <1.0 × 109 cells/L after neutrophil engraftment and less than six months post autologous stem cell transplantation. The primary objective was to determine the incidence of late onset neutropenia. The secondary objectives were to examine whether the use of rituximab with re-induction therapy, mobilization or high dose chemotherapy regimens increased the risk for late onset neutropenia, and to evaluate infectious complications. Of 315 subjects, 92 (29.2%) developed late onset neutropenia. Mobilization regimens containing rituximab (OR 2.90 95% CI: 1.31–6.40), high dose chemotherapy containing rituximab (OR 1.87 95% CI: 1.14–3.05), and exposure to rituximab in either or both regimens (OR 3.05 95% CI: 1.36–6.88) significantly increased the risk of late onset neutropenia. While neutropenic, 17.4% experienced an infection, 7.6% experienced febrile neutropenia, and 5.4% were hospitalized. In conclusion, rituximab with mobilization or high dose chemotherapy may increase the risk of late onset neutropenia post autologous stem cell transplantation.

Effect of FCGR polymorphism on the occurrence of late-onset neutropenia and flare-free survival in rheumatic patients treated with rituximab

Background

The causes and mechanisms of late-onset neutropenia (LON) following rituximab treatment in patients with rheumatic diseases are not known. In this study, we aimed to investigate the role of established Fcγ receptor gene (FCGR) polymorphisms and B-cell-activating factor (BAFF) gene promoter polymorphisms for the development of LON and for the efficacy of rituximab in patients with rheumatic diseases.

Methods

A single-center case-control retrospective study was nested in a cohort of 214 consecutive patients with rheumatic diseases treated with rituximab. Eleven patients presented with LON. Fifty non-LON control subjects were matched by diagnosis, age, sex, and treatments. Single-nucleotide polymorphisms of FCGR (FCGR2A 131H/R, FCGR2B 232I/T, FCGR3A 158V/F) and BAFF promoter polymorphism −871C/T were analyzed with polymerase chain reaction-based techniques, and serum immunoglobulin M (IgM) and BAFF levels were analyzed by enzyme-linked immunosorbent assay. Flare-free survival was related to LON occurrence and polymorphisms.

Results

The FCGR3A V allele, but not other FCGR polymorphisms, correlated with the occurrence of LON; each V allele conferred a fourfold increased OR for LON (p = 0.017). FCGR3A 158V/V and presentation with LON were associated with a longer flare-free survival (p = 0.023 and p = 0.031, respectively). FCGR3A 158V/V was related to lower IgM levels (p = 0.016). Serum BAFF levels showed no relationship with LON and BAFF −871C/T promoter polymorphism. There was a tendency toward longer flare-free survival in patients with the BAFF −871T/T allotype compared with the C/T or C/C allotypes (p = 0.096).

Conclusions

The results of the present study suggest that presentation with LON may be a result of the intrinsic efficacy of rituximab in patients with rheumatic diseases. LON could indicate a longer biological and therapeutic activity of rituximab modulated by a certain genotypic polymorphism: the high-affinity FCGR3A V allele. This genotype and the occurrence of LON are both related to longer flare-free survival, suggestive of common mechanisms for LON and duration of response to rituximab. The role of the BAFF −871C/T promoter polymorphism in LON occurrence is unclear.

Disseminated intravascular coagulation-like reaction following rituximab infusion

Rituximab generally is a well-tolerated medication used in a variety of haematological and autoimmune conditions. The safety profile of the medication has been reviewed in the literature. Infusion reactions due to cytokine release are the most common side effects. With the increased use of rituximab, there is an increase incidence of cytopenias, most commonly thrombocytopenia and leucopenia. Coagulopathy is quite rare, reported previously in four cases in the literature. We highlighted the clinical course of a 39-year-old patient with precursor B-cell acute lymphoblastic leukaemia who was started on rituximab infusion. The patient developed a cytokine-release syndrome with haemodynamic instability, followed by rapid-onset cytopenias and disseminated intravascular coagulation abnormalities characterised by coagulopathy with fibrinolysis and mucocutaneous bleeding. The report is followed by a review of the literature. It is important to recognise rituximab-induced coagulopathy early as part of the differential diagnosis of thrombocytopenia and disseminated intravascular coagulation following rituximab administration.

Challenges in the Role of Gammaglobulin Replacement Therapy and Vaccination Strategies for Hematological Malignancy

Patients with chronic lymphocytic leukemia (CLL) and multiple myeloma (MM) are prone to present with antibody production deficits associated with recurrent or severe bacterial infections that might benefit from human immunoglobulin (Ig) (IVIg/SCIg) replacement therapy. However, the original IVIg trial data were done before modern therapies were available, and the current indications do not take into account the shift in the immune situation of current treatment combinations and changes in the spectrum of infections. Besides, patients affected by other B cell malignancies present with similar immunodeficiency and manifestations while they are not covered by the current IVIg indications. A potential beneficial strategy could be to vaccinate patients at monoclonal B lymphocytosis and monoclonal gammopathy of undetermined significance stages (for CLL and MM, respectively) or at B-cell malignancy diagnosis, when better antibody responses are attained. We have to re-emphasize the need for assessing and monitoring specific antibody responses; these are warranted to select adequately those patients for whom early intervention with prophylactic anti-infective therapy and/or IVIg is preferred. This review provides an overview of the current scenario, with a focus on prevention of infection in patients with hematological malignancies and the role of Ig replacement therapy.

Impact of rituximab maintenance and maintenance schedule on prognosis in first-line treatment of follicular lymphoma. Retrospective analysis from Czech Lymphoma Study Group (CLSG) database

Rituximab maintenance (RM) improves time to progression (PFS) in advanced follicular lymphoma (FL), but the impact of various RM schedules remains unknown. This study performed a retrospective evaluation of RM given for up to 2 years vs observation in 319 untreated FL patients (stage II-IV; grade 1-3A) responding to RCHOP induction and a comparison of two different RM schedules (RM8=eight doses given every 3 months and RM12=12 doses given every 2 months). A total of 183 patients received RM and 136 patients were observed; 5-year PFS was better in the RM arm, 74.1% vs 52.3% (p<0.001), which was projected in 5-year OS 93.8% vs 87.5% (p=0.005). However, 5-year PFS was similar in both the RM8 (n=54) and RM12 (n=56) arms. In the first line, RM significantly prolongs PFS and OS in FL, but different RM schedules bring a similar benefit.

Rituximab treatment strategy for patients with diffuse large B-cell lymphoma after first-line therapy: a systematic review and meta-analysis

BACKGROUND

Rituximab in combination with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) significantly prolonged event-free survival in first-line chemotherapy for patients with diffuse large B-cell lymphoma (DLBCL). But relapse and refractory DLBCL occur frequently. Although rituximab is effective, its role in salvage therapy after autologous transplant remains unclear. Maintenance therapy with rituximab in responding patients after first line chemotherapy may be a useful novel approach capable of eradicating minimal residual disease and to bring survival benefit. This systematic review and meta-analysis evaluated the effects of rituximab maintenance treatment and salvage therapy of patients with DLBCL.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials and compared rituximab maintenance or salvage therapy at relapse with observation. We searched the Cochrane Library, PubMed, EMBASE, conference proceedings, databases of ongoing trials, and references of published trials. Two reviewers independently assessed the quality of the trials and extracted data. Hazard ratios for time-to-event data were estimated and pooled.

RESULTS

Seven trials including 1470 DLBCL patients were included in this systematic review and meta-analysis. Patients treated with maintenance rituximab have better overall survival (OS) and event-free survival (EFS) than patients in the observation arm, but there was no statistical significance. Patients who received rituximab salvage therapy for relapse or refractory DLBCL have statistically significantly better OS [HR of death = 0.72, 95% CI (0.55-0.94), P = 0.02], progression-free survival (PFS) [HR = 0.61, 95% CI (0.52-0.72), P < 0.05], odds ratio (OR) [RR = 1.26, 95% CI (1.07-1.47), P = 0.004] than patients in the observation arm. The rate of infection-related adverse events was higher with rituximab treatment [RR = 1.37, 95% CI = (1.14 - 1.65) P =0.001].

CONCLUSIONS

After first-line chemotherapy, the two rituximab-combined treatment strategies, including maintenance and salvage therapies can bring survival benefit. But due to the few studies, the low methodological quality assessment and the low outcome evidence quality, it's not confirmed that the two strategies are better than normal chemotherapy regimens. More high-quality randomized controlled trials are still needed to provide reliable evidence. The higher rate of infections after rituximab therapy should be taken into consideration when making treatment decisions.

Late-onset neutropenia after treatment with rituximab for rheumatoid arthritis and other autoimmune diseases: data from the AutoImmunity and Rituximab registry

Objectives

To evaluate the prevalence of late-onset neutropenia and its complications in patients treated with rituximab (RTX) for rheumatoid arthritis (RA) and other autoimmune diseases (AIDs) in a prospective registry.

Methods

The AutoImmunity and Rituximab registry is an independent 7-year prospective registry promoted by the French Society of Rheumatology. For each episode of neutropenia, data were validated by the clinician in charge of the patient.

Results

Among 2624 patients treated with RTX for refractory AIDs, and at least 1 follow-up visit (a total follow-up of 4179 patient-years in RA and 987 patient-years in AIDs), late-onset neutropenia was observed in 40 patients (25 RA (1.3% of patients with RA, 0.6/100 patient-years), and AIDs in 15 (2.3% of patients with AIDs, 1.5/100 patient-years)). 6 patients (15%) had neutrophils <500/mm³, 8 (20%) had neutrophils between 500 and 1000/mm³, and 26 (65%) had neutrophils between 1000 and 1500/mm³. Neutropenia occurred after a median period of 4.5 (3–6.5) months after the last RTX infusion in patients with RA, and 5 (3–6.5) months in patients with AIDs. 5 patients (12.5%), 4 of them with neutrophils lower than 500/mm³, developed a non-opportunistic serious infection and required antibiotics and granulocyte colony-stimulating factor injections, with a favourable outcome. After resolution of their RTX-related neutropenia, 19 patients (47.5%) were re-treated, and neutropenia reoccurred in 3 of them.

Conclusions

Late-onset neutropenia might occur after RTX and may result in serious infections. Thus, monitoring of white cell count should be performed after RTX. However, in this large registry of patients with AIDs, the frequency of RTX-induced neutropenia was much lower than that previously reported in patients treated for blood malignancies or AIDs.

Rituximab-related late-onset neutropenia in patients with rheumatic diseases: successful re-challenge of the treatment

BACKGROUND

We describe here 2 patients who developed late-onset neutropenia after Rituximab treatment. While this phenomenon is well described among patients suffering from hematological malignancies, such adverse effects are rare among patients with rheumatic diseases.

CASE REPORT

Two patients, the first with rheumatoid arthritis and the second with granulomatosis with polyangiitis, were treated by Rituximab after all previous treatments failed. The patients developed late-onset neutropenia after several courses of treatment. The first patient, with symptomatic neutropenia, recovered after a single dose of granulocyte macrophage stimulating factor, and the second patient's neutrophils increased spontaneously. Both patients were retreated by rituximab in their scheduled time without further complications.

CONCLUSIONS

Our case series is unique because the same phenomenon appeared in patients with different rheumatic diseases. This case series confirms the possibility of continuing the treatment without further adverse effects.

Rituximab-associated agranulocytosis in children with refractory idiopathic nephrotic syndrome: case series and review of literature

BACKGROUND

Agranulocytosis has been reported as a delayed-onset complication of rituximab treatment. However, the exact incidence and risk factors of this complication in patients with nephrotic syndrome remain unknown.

METHODS

Records of 213 rituximab treatments for 114 patients with refractory nephrotic syndrome between February 2006 and April 2013 were reviewed to identify episodes of agranulocytosis (defined as an absolute neutrophil count of <500 mm(3)).

RESULTS

Eleven episodes of agranulocytosis were detected in 11 patients. Median time of onset of agranulocytosis was 66 days (range, 54-161 days) after rituximab treatment. Nine patients experienced acute infections and received antibiotics. All but one patient received granulocyte colony-stimulating factor. Agranulocytosis resolved in all cases within a median of 3 days. The incidence of agranulocytosis was 9.6% in total patients and 5.2% in all treatments. Median age of the 11 patients who developed agranulocytosis was 6.4 years at the first rituximab treatment, significantly younger than the median age of the 103 patients who did not (median, 12.5 years; P = 0.0009). Five patients received re-treatment with rituximab. No recurrence of agranulocytosis was observed in any patient.

CONCLUSIONS

It is important to pay extra attention to this clinically serious delayed-onset complication as it may be accompanied by life-threatening infections such as sepsis. Further clinical studies are needed to clarify its pathogenesis.

Autoimmune neutropenia

Autoimmune neutropenia (AIN) is a rare entity caused by antibodies directed against neutrophil-specific antigens. It includes primary and secondary autoimmune neutropenia. Acute autoimmune neutropenia can be related to drug-induced mechanism or viral infections. Chronic autoimmune neutropenias occur in the context of autoimmune diseases, hematological malignancies, such as large granular lymphocyte leukemia, primary immune deficiency syndromes or solid tumors. The therapeutic management depends on the etiology. Granulocyte growth factor is the main therapeutic option, raising the question of their long-term utilization safety. Corticosteroids or immunosuppressive therapy are indicated in infection-related AIN or in case of symptomatic autoimmune disease or LGL leukemia.

A Case of an Acquired Factor VIII Inhibitor Complicated by Multiple Treatment-Related Opportunistic Infections and Review of the Literature

This case report describes a patient with an idiopathic acquired Factor VIII inhibitor and severe bleeding. She was treated with rituximab after failing first-line treatment with steroids and cyclophosphamide. Two months following rituximab treatment, our patient developed a succession of severe opportunistic infections requiring intensive care unit admission. Over a period of 12 weeks she required treatment for Pseudomonas aeruginosa septicaemia, herpes simplex gingivostomatitis and pharyngotonsillitis, clostridium difficile-related diarrhoea, systemic cytomegalovirus infection, pneumocystis jiroveci, and invasive pulmonary aspergillosis lung infections. After significant rehabilitation, the patient was finally discharged following a 5-month admission. This case highlights the complexity of balancing a life-threatening condition with the side effects of treatment. It also raises the issue of routine prophylaxis for immunosuppression in nonmalignant conditions, which will become a common dilemma with the expanding indications for rituximab use.

A phase II study of a nonmyeloablative allogeneic stem cell transplant with peritransplant rituximab in patients with B cell lymphoid malignancies: favorably durable event-free survival in chemosensitive patients

The aim of this prospective phase II trial was to determine the safety and efficacy of a nonmyeloablative conditioning program incorporating peritransplant rituximab in patients with CD20+ B cell non-Hodgkin lymphoma (B-NHL) receiving an allogeneic stem cell transplant (allo-SCT). Fifty-one adult B-NHL patients, with a median age of 54 years, were treated with cyclophosphamide, fludarabine, and 200 cGy of total body irradiation. Rituximab 375 mg/m(2) was given on day -8 and in 4 weekly doses beginning day +21. Equine antithymocyte globulin was given to recipients of volunteer unrelated donor grafts. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and mycophenolate mofetil and tacrolimus, sirolimus, and methotrexate in 8 and 43 patients, respectively. Thirty-three patients received grafts from unrelated donors, and 18 received grafts from matched related donors. All patients engrafted. Full donor chimerism in bone marrow and peripheral T cells was seen in 92% and 89% of patients, respectively, at 3 months after allo-SCT. The cumulative incidence of grades II to IV acute GVHD at 6 months was 25% (95% confidence interval [CI], 13% to 38%) and grades III to IV was 11% (95% CI, 2% to 20%). The 2-year cumulative incidence of chronic GVHD was 29% (95% CI, 15% to 44%). The 2-year event-free and overall survival for all patients was 72% (95% CI, 59% to 85%) and 78% (95% CI, 66% to 90%), respectively. The 2-year event-free survival for chemosensitive patients was 84% (95% CI, 72% to 96%) compared with 30% (95% CI, 2% to 58%) for chemorefractory patients before allo-SCT (P < .001). This nonmyeloablative regimen, with peritransplant rituximab, is safe and effective in patients with B-NHL.

Adverse events to monoclonal antibodies used for cancer therapy: Focus on hypersensitivity responses

Fifteen monoclonal antibodies (mAbs) are currently registered and approved for the treatment of a range of different cancers. These mAbs are specific for a limited number of targets (9 in all). Four of these molecules are indeed directed against the B-lymphocyte antigen CD20; 3 against human epidermal growth factor receptor 2 (HER2 or ErbB2), 2 against the epidermal growth factor receptor (EGFR), and 1 each against epithelial cell adhesion molecule (EpCAM), CD30, CD52, vascular endothelial growth factor (VEGF), tumor necrosis factor (ligand) superfamily, member 11 (TNFSF11, best known as RANKL), and cytotoxic T lymphocyte-associated protein 4 (CTLA4). Collectively, the mAbs provoke a wide variety of systemic and cutaneous adverse events including the full range of true hypersensitivities: Type I immediate reactions (anaphylaxis, urticaria); Type II reactions (immune thrombocytopenia, neutopenia, hemolytic anemia); Type III responses (vasculitis, serum sickness; some pulmonary adverse events); and Type IV delayed mucocutaneous reactions as well as infusion reactions/cytokine release syndrome (IRs/CRS), tumor lysis syndrome (TLS), progressive multifocal leukoencephalopathy (PML) and cardiac events. Although the term "hypersensitivity" is widely used, no common definition has been adopted within and between disciplines and the requirement of an immunological basis for a true hypersensitivity reaction is sometimes overlooked. Consequently, some drug-induced adverse events are sometimes incorrectly described as "hypersensitivities" while others that should be described are not.

Late-onset neutropenia during long-term rituximab therapy in neuromyelitis optica

Late-onset neutropenia (LON) has been described as a side effect of rituximab (RX) therapy in patients with rheumatological and/or haematooncological diseases but not neuromyelitis optica (NMO). We describe a 71-year old female patient, who had NMO for 22 years, had been treated with RX monotherapy five times (cumulative dosage: 11g; duration of treatment: 3 years) before she developed severe neutropenia (IV) 3 months after the last RX infusion.(1) After exclusion of other causes, the diagnosis of LON was made. No complications occurred and neutropenia resolved without therapy. RX therapy was continued with intensive monitoring without any further LON and/or complications. In conclusion LON is a possible side effect during RX therapy and may also occur in NMO patients.

Leveraging administrative data to monitor rituximab use in 2875 patients at 42 freestanding children's hospitals across the United States

OBJECTIVE

To describe the pharmacoepidemiology of rituximab use in children and to estimate the frequency of infectious events within a 1-year period after rituximab exposure.

STUDY DESIGN

This is a retrospective cohort study of patients who received rituximab at 1 of 42 children's hospitals contributing data to the Pediatric Health Information System between January 1999 and June 2011. International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) discharge diagnosis codes were analyzed to categorize underlying diseases (hematologic malignancies, primary immunodeficiencies, autoimmune diseases, and transplant recipients) and to estimate inpatient infectious complication rates within each category.

RESULTS

A total of 2875 patients with 4639 rituximab admissions were identified. The median age at index admission was 11 years (IQR, 5-15 years). The rate of rituximab admissions increased from 3 to 185 per 100,000 admissions per year over the study interval. During the 1-year follow-up period, 463 patients (16%) died. Infectious events were assessed in 2246 of the rituximab-exposed patients; 6.1% were diagnosed with sepsis and 2.0% with septic shock. The frequency of sepsis ranged from 2.4% in patients with autoimmune diseases to 12.2% in those with primary immunodeficiencies. Three patients were assigned an ICD-9-CM discharge diagnosis code for Pneumocystis joroveci pneumonia, 1 patient was assigned an ICD-9-CM discharge diagnosis code for hepatitis B, and 1 patient was assigned an ICD-9-CM discharge diagnosis code for progressive multifocal leukoencephalopathy.

CONCLUSION

The use of rituximab has increased significantly in children with a variety of underlying diseases. Based on ICD-9-CM code data, the rates of sepsis and other life-threatening infections after rituximab exposure vary depending on the underlying condition. Based on surveillance of infection using ICD-9-CM diagnosis codes, the rates of opportunistic infections appear to be low.

Rituximab purging and/or maintenance in patients undergoing autologous transplantation for relapsed follicular lymphoma: a prospective randomized trial from the lymphoma working party of the European group for blood and marrow transplantation

PURPOSE

The objective of this randomized trial was to assess the efficacy and safety of rituximab as in vivo purging before transplantation and as maintenance treatment immediately after high-dose chemotherapy and autologous stem-cell transplantation (HDC-ASCT) in patients with relapsed follicular lymphoma (FL).

PATIENTS AND METHODS

Patients with relapsed FL who achieved either complete or very good partial remission with salvage chemotherapy were randomly assigned using a factorial design to rituximab purging (P+; 375 mg/m(2) once per week for 4 weeks) or observation (NP) before HDC-ASCT and to maintenance rituximab (M+; 375 mg/m(2) once every 2 months for four infusions) or observation (NM).

RESULTS

From October 1999 to April 2006, 280 patients were enrolled. The median age was 51 years (range, 26 to 70 years), and baseline characteristics were well balanced between groups. On average, patients were 44 months (range, 3 to 464 months) from diagnosis, with 79% having received two lines and 15% three lines of prior therapy. Median follow-up was 8.3 years. In contrast to purging, 10-year progression-free survival (PFS) was 48% for P+ and 42% for NP groups (hazard ratio [HR], 0.80; 95% CI, 0.58 to 1.11; P = .18); maintenance had a significant effect on PFS (10-year PFS, 54% for M+ and 37% for NM; HR, 0.66; 95% CI, 0.47 to 0.91; P = .012). Overall survival (OS) was not improved by either rituximab purging or maintenance.

CONCLUSION

Rituximab maintenance after HDC-ASCT is safe and significantly prolongs PFS but not OS in patients undergoing transplantation for relapsed FL. Pretransplantation rituximab in vivo purging, even in rituximab-naive patients, failed to improve PFS or OS.

Rituximab for managing acquired hemophilia A in a case of chronic neutrophilic leukemia with the JAK2 kinase V617F mutation

Background

Acquired hemophilia A is rarely found in association with myeloproliferative neoplasms, such as the JAK2 kinase V617F mutation-positive chronic neutrophilic leukemia (CNL).

Case report

An 80-year-old Japanese male was diagnosed with acquired hemophilia A. He had compartment-like symptoms due to soft tissue hemorrhage in his left forearm and right lower extremity. A blood examination showed neutrophilia with a white blood cell count of 31,900/μL (91.9% neutrophils), an activated partial thromboplastin time of 69.0 seconds, coagulation factor VIII (FVIII) < 1.0%, and anti-FVIII inhibitor, 190 BU/mL. The bleeding episodes were controlled with intravenous activated prothrombin complex concentrate (FEIBA^®) followed by recombinant factor VIIa (NovoSeven^®). In addition, oral prednisolone (maximum dose, 30 mg/day) plus four doses of rituximab effectively suppressed anti-FVIII inhibitor levels while simultaneously reducing the neutrophil count. CNL with the JAK2 kinase V617F mutation was identified as the underlying disease.

Conclusion

This report describes the effectiveness of a combination of prednisolone and rituximab in managing acquired hemophilia A in an elderly man with a rare case of JAK2 kinase V617F mutation-positive CNL.

Prolonged immunochemotherapy with rituximab, cytarabine and fludarabine added to cyclophosphamide, doxorubicin, vincristine and prednisolone and followed by rituximab maintenance in untreated elderly patients with mantle cell lymphoma: a prospective study by the Finnish Lymphoma Group

There is no consensus on treatment strategies for elderly patients with mantle cell lymphoma (MCL). In this prospective phase II study we investigated whether the poor outcome could be improved, with reasonable toxicity, by prolonging the immunochemotherapy. Ten cycles of alternating cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP)/cytarabine (AraC) with eight doses of rituximab (R) were given as induction. The potential synergism of intermediate-dose AraC and fludarabine was tested in cycles 6-8. Induction was followed by bimonthly rituximab maintenance for 2 years. The median age of the 60 included patients was 74 years, and the Mantle Cell Lymphoma International Prognostic Index (MIPI) was intermediate or high risk in 98% of the patients. The overall response rate was 95% (complete response/complete response unconfirmed 87%). The response of 11 patients improved with cycles 6-8 (R-fludarabine-AraC). Progression-free survival was 70% and overall survival 72% at 4 years, respectively. Treatment related mortality was 2%. Severe infections were rare, with only one grade 4 infection. More dose reductions were needed during fludarabine-containing courses as compared to R-AraC. In 20 patients a transient grade 4 neutropenia without severe infections was recorded during maintenance. In conclusion, elderly patients with MCL can be treated relatively intensively with acceptable toxicity.

‘Les liaisons dangereuses’: Hepatitis C, Rituximab and B-cell non-Hodgkin’s lymphomas

Rituximab has provided a revolutionary contribution to the treatment of B-cell non-Hodgkin’s lymphomas (NHL). A high prevalence of hepatitis C virus (HCV) infection has been described in B-cell NHL patients. Cases of liver dysfunction in HCV-positive patients have been reported with Rituximab-containing regimens. In this paper we review the recent data regarding the effects of Rituximab in NHL patients with HCV infection. We also added a section devoted to improving communication between oncohaematologists and hepatologists. Furthermore, we propose a common methodological ground to study hepatic toxicity emerging during chemotherapy.