The evolving landscape of COVID-19 and post-COVID condition in patients with chronic lymphocytic leukemia: A study by ERIC, the European research initiative on CLL

In this retrospective international multicenter study, we describe the clinical characteristics and outcomes of patients with chronic lymphocytic leukemia (CLL) and related disorders (small lymphocytic lymphoma and high-count monoclonal B lymphocytosis) infected by SARS-CoV-2, including the development of post-COVID condition. Data from 1540 patients with CLL infected by SARS-CoV-2 from January 2020 to May 2022 were included in the analysis and assigned to four phases based on cases disposition and SARS-CoV-2 variants emergence. Post-COVID condition was defined according to the WHO criteria. Patients infected during the most recent phases of the pandemic, though carrying a higher comorbidity burden, were less often hospitalized, rarely needed intensive care unit admission, or died compared to patients infected during the initial phases. The 4-month overall survival (OS) improved through the phases, from 68% to 83%, p = .0015. Age, comorbidity, CLL-directed treatment, but not vaccination status, emerged as risk factors for mortality. Among survivors, 6.65% patients had a reinfection, usually milder than the initial one, and 16.5% developed post-COVID condition. The latter was characterized by fatigue, dyspnea, lasting cough, and impaired concentration. Infection severity was the only risk factor for developing post-COVID. The median time to resolution of the post-COVID condition was 4.7 months. OS in patients with CLL improved during the different phases of the pandemic, likely due to the improvement of prophylactic and therapeutic measures against SARS-CoV-2 as well as the emergence of milder variants. However, mortality remained relevant and a significant number of patients developed post-COVID conditions, warranting further investigations.

BRAF V600E is associated with higher incidence of second cancers in adults with Langerhans cell histiocytosis

In this retrospective study, BRAF mutation status did not correlate with disease extent or (event-free) survival in 156 adults with Langerhans cell histiocytosis. BRAFV600E was associated with an increased incidence of second malignancies, often comprising hematological cancers, which may be clonally related.

Fixed-duration venetoclax plus obinutuzumab improves quality of life and geriatric impairments in FCR-unfit patients with CLL

Chronic lymphocytic leukemia (CLL)-related symptoms and morbidity related to the advanced age at diagnosis impairs the well-being of older adult patients. Therefore, it is essential to tailor treatment according to geriatric characteristics and aim for an improvement in health-related quality of life (HRQoL) as a primary treatment goal. In the HOVON139/GiVe trial, 12 cycles of fixed-duration venetoclax plus obinutuzumab (Ven-O) were shown to be effective and tolerable in FCR (fludarabine, cyclophosphamide, rituximab)-unfit patients with CLL (n = 67). However, prolonged venetoclax exposure as consolidation treatment led to increased toxicity with limited effect on minimal residual disease. To assess the impact of geriatric assessment on treatment outcomes and the patients' HRQoL, patient-reported outcomes (PROs), including function, depression, cognition, nutrition, physical performance, muscle parameters, comorbidities, and the European Organization for Research and Treatment of Cancer C30 and CLL17 questionnaires were assessed. At baseline, geriatric impairments were present in >90% of patients and ≥2 impairments present in 60% of patients predicted grade ≥3 nonhematological toxicity. During treatment, the number of geriatric impairments diminished significantly and clinically relevant improvements in HRQoL subscales were reached for global health status, physical functioning, role functioning, emotional functioning, fatigue, dyspnea, physical condition or fatigue, and worries or fears related to health and functioning. These improvements were comparable for patients receiving venetoclax consolidation and patients in whom treatment could mostly be discontinued. Collectively, frontline fixed-duration Ven-O improves overall PROs in older, unfit patients with CLL with and without geriatric impairments. This study was registered at EudraCT as 2015-004985-27 and the Netherlands Trial Register as NTR6043.

A population-based study of transformed marginal zone lymphoma: identifying outcome-related characteristics

Histological transformation of marginal zone lymphoma (tMZL) into diffuse large B-cell lymphoma is associated with poor outcomes. Clinical characteristics associated with transformation risk and outcome after transformation are largely unknown due to scarcity of data. In this population-based study, competing risk analyses were performed to elucidate clinical characteristics associated with developing transformation among 1793 MZL patients using the Netherlands Cancer Registry. Cox regression analyses were performed to elucidate clinical characteristics associated with risk of relapse and mortality after transformation. Transformation occurred in 75 (4%) out of 1793 MZL patients. Elevated LDH and nodal MZL subtype at MZL diagnosis were associated with an increased risk, and radiotherapy with a reduced risk of developing tMZL. Most tMZL patients received R-(mini)CHOP (n = 53, 71%). Age >60 years and (immuno)chemotherapy before transformation were associated with an increased risk of relapse and mortality after transformation. Two-year progression-free survival (PFS) and overall survival (OS) were 66% (95% CI 52-77%) and 75% (95% CI 62-85%) for R-(mini)CHOP-treated tMZL patients, as compared to a PFS and OS both of 41% (95% CI 19-63%) for patients treated otherwise. Our study offers comprehensive insights into characteristics associated with transformation and survival after transformation, thereby optimizing guidelines and patient counseling.

Prognostic value of TARC and quantitative PET parameters in relapsed or refractory Hodgkin lymphoma patients treated with brentuximab vedotin and DHAP

Risk-stratified treatment strategies have the potential to increase survival and lower toxicity in relapsed/refractory classical Hodgkin lymphoma (R/R cHL) patients. This study investigated the prognostic value of serum (s)TARC, vitamin D and lactate dehydrogenase (LDH), TARC immunohistochemistry and quantitative PET parameters in 65 R/R cHL patients who were treated with brentuximab vedotin (BV) and DHAP followed by autologous stem-cell transplantation (ASCT) within the Transplant BRaVE study (NCT02280993). At a median follow-up of 40 months, the 3-year progression free survival (PFS) was 77% (95% CI: 67-88%) and the overall survival was 95% (90-100%). Significant adverse prognostic markers for progression were weak/negative TARC staining of Hodgkin Reed-Sternberg cells in the baseline biopsy, and a high standard uptake value (SUV)mean or SUVpeak on the baseline PET scan. After one cycle of BV-DHAP, sTARC levels were strongly associated with the risk of progression using a cutoff of 500 pg/ml. On the pre-ASCT PET scan, SUVpeak was highly prognostic for progression post-ASCT. Vitamin D, LDH and metabolic tumor volume had low prognostic value. In conclusion, we established the prognostic impact of sTARC, TARC staining, and quantitative PET parameters for R/R cHL, allowing the use of these parameters in prospective risk-stratified clinical trials. Trial registration: NCT02280993.

Impact of mucositis on oral bioavailability and systemic exposure of ciprofloxacin Gram-negative infection prophylaxis in patients with haematological malignancies

BACKGROUND

Patients with haematological malignancies frequently endure neutropenia and gastrointestinal (GI)-mucositis after high-dose chemotherapy. In these patients, ciprofloxacin is used for Gram-negative infection prophylaxis.

OBJECTIVES

We investigate ciprofloxacin pharmacokinetics after oral administration in patients with haematological malignancies and explore the impact of GI-mucositis on oral bioavailability and clearance in order to assure adequate systemic exposure.

METHODS

Adult haematological patients from two Dutch University Medical Centres received 500 mg twice daily oral ciprofloxacin for Gram-negative prophylaxis. The ciprofloxacin plasma concentrations were collected at various timepoints after oral ciprofloxacin administration and at various days after completion of chemotherapy. Data obtained after oral and intravenous ciprofloxacin administration in 28 healthy volunteers without mucositis served as a control group (391 samples). For haematological patients the degree of GI-mucositis was assessed using the Daily Gut Score (DGS), plasma citrulline and albumin. Data were analysed by non-linear mixed-effects modelling.

RESULTS

In total, 250 blood samples were collected in 47 patients with a wide variety of haematological malignancies between 0-30 days after start of chemotherapy. Mucositis was generally mild [DGS median (IQR) 1 (1-1) and citrulline 16 μmol/L (12-23)]. The time to Cmax was slower in haematological patients compared with healthy volunteers although no association with the degree of mucositis (defined as DGS or citrulline) could be identified. Ciprofloxacin bioavailability and clearance were 60% and 33.2 L/h, respectively.

CONCLUSIONS

This study supports oral dosing of ciprofloxacin as Gram-negative infection prophylaxis in haematological patients with mild-to-moderate mucositis capable of oral intake.

How to choose first salvage therapy in Hodgkin lymphoma: traditional chemotherapy vs novel agents

Approximately 10% to 30% of patients with classical Hodgkin lymphoma (cHL) develop relapsed or refractory (R/R) disease. Of those patients, 50% to 60% show long-term progression-free survival after standard salvage chemotherapy followed by high-dose chemotherapy (HDCT) and autologous stem cell transplant (ASCT). In the past decade, novel therapies have been developed, such as the CD30-directed antibody-drug conjugate brentuximab vedotin and immune checkpoint inhibitors, which have greatly extended the treatment possibilities for patients with R/R cHL. Several phase 1/2 clinical trials have shown promising results of these new drugs as monotherapy or in combination with chemotherapy, but unfortunately, very few randomized phase 3 trials have been performed in this setting, making it difficult to give evidence-based recommendations for optimal treatment sequencing. Two important goals for the improvement in the treatment of R/R cHL can be identified: (1) increasing long-term progression-free and overall survival by optimizing risk-adapted treatment and (2) decreasing toxicity in patients with a low risk of relapse of disease by evaluating the need for HDCT/ASCT in these patients. In this review, we discuss treatment options for patients with R/R cHL in different settings: patients with a first relapse, primary refractory disease, and in patients who are ineligible or unfit for ASCT. Results of clinical trials investigating novel therapies or strategies published over the past 5 years are summarized.

Combining brentuximab vedotin with dexamethasone, high-dose cytarabine and cisplatin as salvage treatment in relapsed or refractory Hodgkin lymphoma: the phase II HOVON/LLPC Transplant BRaVE study

Achieving a metabolic complete response (mCR) before high-dose chemotherapy (HDC) and autologous peripheral blood stem-cell transplant (auto-PBSCT) predicts progression free survival (PFS) in relapsed/refractory classical Hodgkin lymphoma (R/R cHL). We added brentuximab vedotin (BV) to DHAP to improve the mCR rate. In a Phase I dose-escalation part in 12 patients, we showed that BV-DHAP is feasible. This Phase II study included 55 R/R cHL patients (23 primary refractory). Treatment consisted of three 21-day cycles of BV 1.8 mg/kg on day 1, and DHAP (dexamethasone 40mg days 1-4, cisplatin 100mg/m2; day 1 and cytarabine 2x2g/m2; day 2). Patients with a metabolic partial response (mPR) or mCR proceeded to HDC/auto-PBSCT. Based on independent central FDG-PET-CT review, 42 of 52 evaluable patients (81% [95% CI: 67-90]) achieved an mCR before HDC/auto-PBSCT, five had an mPR and five had progressive disease (three were not evaluable). After HDC/auto-PBSCT, four patients with an mPR converted to an mCR. The 2-year PFS was 74% [95% CI: 63-86], and the overall survival 95% [95% CI: 90-100]. Toxicity was manageable and mainly consisted of grade 3/4 hematological toxicity, fever, nephrotoxicity, ototoxicity (grade 1/2) and transiently elevated liver enzymes during BV-DHAP. Eighteen patients developed new onset peripheral neuropathy (maximum grade 1/2) and all recovered. In conclusion, BV-DHAP is a very effective salvage regimen in R/R cHL patients, but patients should be monitored closely for toxicity. ClinicalTrials.gov identifier: NCT02280993.

CD3xCD19 DART molecule treatment induces non-apoptotic killing and is efficient against high-risk chemotherapy and venetoclax-resistant chronic lymphocytic leukemia cells

BACKGROUND

Bispecific antibodies are promising new therapeutics in B cell malignancies. Whether they lead to potent T cell activation despite described T cell dysfunction in chronic lymphocytic leukemia (CLL), and are able to effectively target high-risk or venetoclax-resistant samples, is currently unknown.

METHODS

CD19⁺ cell lines or primary (high-risk) CLL were cocultured in vitro with healthy donor (HD) or CLL-derived T cells in the presence of a CD3xCD19 dual affinity retargeting molecule (CD3xCD19 DART). Cell cytotoxicity, T cell activation, proliferation and effector molecule production were analyzed using flow cytometry.

RESULTS

Here, we report that a bispecific CD3xCD19 DART mediates efficient killing by HD T cells of CD19⁺ cell-lines and primary CLL cells, regardless of immunoglobulin heavy chain variable region (IGHV) mutational status TP53 status or chemotherapy, ibrutinib or venetoclax sensitivity. Whereas TCR stimulation of CLL-derived T cells resulted in dysfunctional T cell activation and proliferation, treatment with CD3xCD19 DART led to a similar activation profile in CLL-derived and HD-derived T cells. Consistently, co-culture of CLL derived T cells with JeKo-1 or CLL cells in the presence of CD3xCD19 DART resulted in significant cytotoxicity by both CD4⁺ and CD8⁺ T cells. On stimulation of CLL cells with CD40L, CLL cells become resistant to the specific inhibitor of anti-apoptotic Bcl-2 protein venetoclax, due to upregulation of Bcl-2 family members such as Bcl-XL. Nevertheless, CD40L stimulated CLL cells were as efficiently lysed on CD3xCD19 DART treatment as unstimulated CLL cells. Further examination of the mechanism of CD3xCD19 DART mediated killing showed that lysis was dependent on granules, but was independent of BAX/BAK or caspase activity, indicating non-apoptotic cell death.

CONCLUSIONS

These data show that CD3xCD19 DART in CLL leads to robust T cell activation and lysis of high-risk venetoclax resistant CLL cells through a non-apoptotic mechanism.

Overcoming the Hurdles of Autologous T-Cell-Based Therapies in B-Cell Non-Hodgkin Lymphoma

Simple Summary

The activity of novel therapies that utilize patient’s own T-cells to induce remission of B-cell non-Hodgkin lymphoma (B-NHL), including chronic lymphocytic leukemia (CLL), is still suboptimal. In this review, we summarize the clinical efficacy of T-cell-based therapies in B-NHL and provide a biologic rationale for the observed (lack of) responses. We describe and compare the acquired T-cell dysfunctions that occur in the different subtypes of B-NHL. Furthermore, we discuss new insights that could enhance the efficacy of T-cell-based therapies for B-NHL and CLL.

Abstract

The next frontier towards a cure for B-cell non-Hodgkin lymphomas (B-NHL) is autologous cellular immunotherapy such as immune checkpoint blockade (ICB), bispecific antibodies (BsAbs) and chimeric antigen receptor (CAR) T-cells. While highly successful in various solid malignancies and in aggressive B-cell leukemia, this clinical success is often not matched in B-NHL. T-cell subset skewing, exhaustion, expansion of regulatory T-cell subsets, or other yet to be defined mechanisms may underlie the lack of efficacy of these treatment modalities. In this review, a systematic overview of results from clinical trials is given and is accompanied by reported data on T-cell dysfunction. From these results, we distill the underlying pathways that might be responsible for the observed differences in clinical responses towards autologous T-cell-based cellular immunotherapy modalities between diffuse large B-cell lymphoma (DLBCL), chronic lymphocytic leukemia (CLL), follicular lymphoma (FL), mantle cell lymphoma (MCL), and marginal zone lymphoma (MZL). By integration of the clinical and biological findings, we postulate strategies that might enhance the efficacy of autologous-based cellular immunotherapy for the treatment of B-NHL.

Human CXCR5+ PD-1+ CD8 T cells in healthy individuals and patients with hematologic malignancies

Immune checkpoint blockade (ICB) has revolutionized cancer therapy, but varying response rates illustrate the need for biomarkers of response. Studies in mice have identified a subset of CD8 T cells that is essential for response to PD‐1 ICB. These CD8 T cells co‐express CXCR5, PD‐1 and Tcf1, and provide effector T cells upon PD‐1 ICB. It is unknown whether similar T cells play a role in PD‐1 ICB in humans.

We studied human peripheral blood and lymph nodes (LNs) for the frequency, phenotype, and functionality of CXCR5⁺PD‐1⁺ CD8 T cells. We find that CXCR5⁺PD‐1⁺ CD8 T cells are memory‐like cells, express Tcf1, and lack expression of effector molecules. CXCR5⁺PD‐1⁺ CD8 T cells produce cytokines upon stimulation, but have limited proliferative capacity. We studied patients with hematologic malignancies with varying response rates to PD‐1 ICB. Specifically in chronic lymphocytic leukemia, in which PD‐1 ICB does not induce clinical responses, CXCR5⁺PD‐1⁺ CD8 T cells show loss of the memory phenotype and increased effector differentiation.

In conclusion, we identified CXCR5⁺PD‐1⁺ CD8 T cells in human peripheral blood and LN, which could play a similar role during PD‐1 ICB. Future studies should analyze CXCR5⁺PD‐1⁺ CD8 T cells during PD‐1 ICB and their importance for therapeutic response.

The impact of prior malignancies on the development of second malignancies and survival in follicular lymphoma: A population‐based study

We assessed the impact of a prior malignancy diagnosis (PMD) – as a potential proxy for genetic cancer susceptibility – on the development of a second primary malignancy (SPM) and mortality in follicular lymphoma (FL) patients. From the nationwide Netherlands Cancer Registry, we selected all adult FL patients diagnosed in 1994‐2012 (n = 8028) and PMDs and SPMs relative to FL, with follow‐up until 2017. We constructed two Fine and Gray models – with death as a competing risk – to assess the association between a PMD and SPM incidence. A PMD was associated with an increased incidence of SPMs (subdistribution hazard ratio [SHR], 1.30; 95% confidence interval [CI], 1.03‐1.64) – especially carcinomas of the respiratory tract (SHR, 1.83; 95% CI, 1.10‐3.05) and cutaneous squamous cell carcinomas (SHR, 1.58; 95% CI, 1.01‐2.45) – and a higher risk of mortality in a multivariable model (HR, 1.43; 95% CI, 1.19‐1.71). However, when additionally adjusted for the receipt of systemic therapy and/or radiotherapy before FL diagnosis, only patients who received such therapies had an increased incidence of SPMs (SHR, 1.40; 95% CI, 1.02‐1.93). In conclusion, patients with a PMD had a higher rate of SPMs and mortality than those without a PMD, which might have resulted from therapy‐related carcinogenesis.

Proteomic markers with prognostic impact on outcome of chronic lymphocytic leukemia patients under chemo-immunotherapy: results from the HOVON 109 study

Despite recent identification of several prognostic markers, there is still a need for new prognostic parameters able to predict clinical outcome in chronic lymphocytic leukemia (CLL) patients. Here, we aimed to validate the prognostic ability of known (proteomic) markers measured pretreatment and to search for new proteomic markers that might be related to treatment response in CLL. To this end, baseline serum samples of 51 CLL patients treated with chemo-immunotherapy were analyzed for 360 proteomic markers, using Olink technology. Median event-free survival (EFS) was 23 months (range: 1.25-60.9). Patients with high levels of sCD23 (>11.27, p = 0.026), sCD27 (>11.03, p = 0.04), SPINT1 (>1.6, p = 0.001), and LY9 (>8.22, p = 0.0003) had a shorter EFS than those with marker levels below the median. The effect of sCD23 on EFS differed between immunoglobulin heavy chain variable gene-mutated and unmutated patients, with the shortest EFS for unmutated CLL patients with sCD23 levels above the median. Taken together, our results validate the prognostic impact of sCD23 and highlight SPINT1 and LY9 as possible promising markers for treatment response in CLL patients.

Ibrutinib-associated invasive fungal diseases in patients with chronic lymphocytic leukaemia and non-Hodgkin lymphoma: An observational study

BACKGROUND

Invasive fungal diseases (IFD) are life-threatening infections most commonly diagnosed in acute leukaemia patients with prolonged neutropenia and are uncommonly diagnosed in patients with lymphoproliferative diseases.

OBJECTIVES

Following the initial report of aspergillosis diagnosed shortly after beginning ibrutinib for chronic lymphocytic leukaemia, a survey was developed to seek additional cases of IFD during ibrutinib treatment.

METHODS

Local and international physicians and groups were approached for relevant cases. Patients were included if they met the following criteria: diagnosis of chronic lymphocytic leukaemia/non-Hodgkin lymphoma; proven or probable IFD; and ibrutinib treatment on the date IFD were diagnosed. Clinical and laboratory data were captured using REDCap software.

RESULT

Thirty-five patients with IFD were reported from 22 centres in eight countries: 26 (74%) had chronic lymphocytic leukaemia. The median duration of ibrutinib treatment before the onset of IFD was 45 days (range 1-540). Aspergillus species were identified in 22 (63%) of the patients and Cryptococcus species in 9 (26%). Pulmonary involvement occurred in 69% of patients, cranial in 60% and disseminated disease in 60%. A definite diagnosis was made in 21 patients (69%), and the mortality rate was 69%. Data from Israel regarding ibrutinib treated patients were used to evaluate a prevalence of 2.4% IFD.

CONCLUSIONS

The prevalence of IFD among chronic lymphocytic leukaemia/non-Hodgkin lymphoma patients treated with ibrutinib appears to be higher than expected. These patients often present with unusual clinical features. Mortality from IFD in this study was high, indicating that additional studies are urgently needed to identify patients at risk for ibrutinib-associated IFD.

Engaging Cytotoxic T and NK Cells for Immunotherapy in Chronic Lymphocytic Leukemia

Chronic lymphocytic leukemia (CLL) is characterized by an acquired immune dysfunction. CLL cells affect the phenotype and function of the entire spectrum of innate and adaptive immune cells, including monocytes, T cells, and natural killer (NK) cells, leading to a tumor-supportive environment and reduced immunosurveillance. Novel immunotherapies like immune checkpoint blockade, bi- and tri-specific antibodies, and chimeric antigen receptor (CAR) T cells use the patients' immune system to induce therapeutic responses. Although these novel immunotherapies showed impressive results in several B cell lymphomas, responses in CLL were often disappointing. The strong immunomodulatory effect of CLL is believed to play a pivotal role in the low response rates to these immunotherapeutic strategies. In this review, we summarize how CLL influences the function of non-malignant lymphocytes, with a special focus on T and NK cells, two important cellular mediators for immunotherapy. Secondly, we provide a short overview of the activity of several immunotherapeutics in CLL, and discuss how novel strategies may overcome the disappointing response rates in CLL.

Induction of TAp73 by platinum-based compounds to overcome drug resistance in p53 dysfunctional chronic lymphocytic leukemia

In chronic lymphocytic leukemia (CLL), strategies to overcome drug resistance due to p53 dysfunction are highly needed. Platinum-based compounds such as cisplatinum (CDDP) are active in fludarabine-refractory CLL through a largely unknown mechanism. We analyzed the mechanism of action of CDDP in the context of p53 dysfunctionality. In vitro treatment with CDDP did not induce death in quiescent CLL cells, but did induce apoptosis in CD40-ligand (and CpG) stimulated and proliferating cells, irrespective of p53 function. In the p53 dysfunctional prolymphocytic cell-line MEC1, CDDP treatment resulted in apoptosis, cell cycle arrest and ABL1-dependent expression of TAp73, CDKN1A, PUMA and BID. TAp73 RNA-interference decreased sensitivity to CDDP. Finally, both in vitro stimulated CLL cells and lymph node (LN) derived CLL cells showed increased TAp73 expression in comparison with quiescent peripheral blood derived cells. Activity of CDDP may therefore be mediated by TAp73, especially in the context of activation such as occurs in the LN microenvironment.

Dasatinib in combination with fludarabine in patients with refractory chronic lymphocytic leukemia: a multicenter phase 2 study

Resistance to chemotherapy-induced apoptosis in CLL is associated with overexpression of antiapoptotic proteins induced by signals from the microenvironment. In vitro, dasatinib effectively inhibits expression of anti-apoptotic regulators and restores fludarabine sensitivity in activated CLL. The aim of this study was to evaluate efficacy of one cycle of dasatinib monotherapy (100mg/day, days 1-28) followed by combination of dasatinib with fludarabine (40mg/m²/day, days 1-3 every 28 day) for a total of 6 cycles in fludarabine-refractory CLL. The primary endpoint was overall response rate according to the IWCLL'08 criteria. 20 patients were enrolled: 18 completed at least one cycle of treatment of which 67% finished at least 2 cycles of combination treatment. 3 of these 18 patients reached a formal PR (16.7%). Majority of patients obtained some reduction in lymph node (LN) size. Most frequent toxicity was related to myelosuppression. NF-κB RNA expression levels of circulating CLL cells decreased whereas the levels of pro-apoptotic NOXA increased during treatment. In conclusion, dasatinib/fludarabine combination has modest clinical efficacy in fludarabine-refractory patients.

Chest pain in sickle cell disease

The differential diagnosis of chest pain in a patient with sickle cell disease is difficult and may encompass several serious conditions, including chest syndrome, pulmonary embolism and infectious complications. In this manuscript we provide an overview on the various underlying diseases that may cause chest pain in patients with sickle cell disease and provide clues for a proper diagnostic workup.

Expansion of effector T cells associated with decreased PD-1 expression in patients with indolent B cell lymphomas and chronic lymphocytic leukemia

In patients with chronic lymphocytic leukemia (CLL), numbers of CD8 + CD45RA +/- CD27- effector T cells are expanded. We investigated whether this expansion is also present in other B cell malignancies and the possible mechanism underlying these changes. Whereas an increase in total CD4+and CD8+ T cell numbers was found only in CLL, numbers of CD4+ and CD8+ effector T cells were significantly increased in both CLL and indolent lymphoma, but not aggressive lymphoma and myeloma. Interestingly, PD-1 expression was decreased on effector T cells and inversely correlated with effector T cell numbers, suggesting a functional role for PD-1 in regulating T cell homeostasis. In vitro experiments revealed impaired up-regulation of PD-1 upon T cell activation in the presence of malignant but also healthy B cells. Our data suggest that in CLL and indolent lymphoma, the malignant B cells affect PD-1 expression on effector T cells, resulting in an expansion of these subsets.

Standards for the treatment of relapsed chronic lymphocytic leukemia: a case-based study

In recent years, considerable advances have been made in first-line treatment strategies for chronic lymphocytic leukemia (CLL). Combination of conventional chemotherapy with immunotherapeutic agents is currently considered the most active strategy, with improved progression-free survival and overall survival. However, patients are not cured and invariably experience relapsing disease requiring treatment. In contrast to the advances made in first-line treatment strategies, much less progress has been made for patients with relapsed and especially refractory CLL. The activity of most chemotherapeutic drugs used in CLL rely on intact p53 function, and repeated cycles of therapy might eventually result in drug resistance because of acquired cytogenetic alterations, mainly affecting genes involved in the p53 response. As a consequence, most commonly used treatment regimens are ineffective in patients with refractory disease. A number of promising alternative treatment approaches are currently under investigation. In this review, the approach to patients with relapsed and refractory CLL and current promising experimental treatment options for these distinct clinical patient categories are discussed.