Efficacy of a third BNT162b2 mRNA COVID-19 vaccine dose in patients with CLL who failed standard 2-dose vaccination.

Patients with chronic lymphocytic leukemia (CLL) have an impaired antibody response to coronavirus disease 2019 (COVID-19) vaccination. Here, we evaluated the antibody response to a third BNT162b2 mRNA vaccine in patients with CLL/small lymphocytic lymphoma (SLL) who failed to achieve a humoral response after standard 2-dose vaccination regimen. Anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies were measured 3 weeks after administration of the third dose. In 172 patients with CLL, the antibody response rate was 23.8%. Response rate among actively treated patients (12.0%; n = 12/100) was lower compared with treatment-naïve patients (40.0%; n = 16/40; OR = 4.9, 95% CI 1.9-12.9; P < .001) and patients off-therapy (40.6%; n = 13/32; OR = 5.0, 95% CI 1.8-14.1; P < .001), (P < .001). In patients actively treated with Bruton's tyrosine kinase (BTK) inhibitors or venetoclax ± anti-CD20 antibody, response rates were extremely low (15.3%, n = 9/59, and 7.7%, n = 3/39, respectively). Only 1 of the 28 patients (3.6%) treated with anti-CD20 antibodies <12 months prior to vaccination responded. In a multivariate analysis, the independent variables that were associated with response included lack of active therapy (OR = 5.6, 95% CI 2.3-13.8; P < .001) and serum immunoglobulin A levels ≥80 mg/dL (OR = 5.8, 95% CI 2.1-15.9; P < .001). In patients with CLL/SLL who failed to achieve a humoral response after standard 2-dose BNT162b2 mRNA vaccination regimen, close to a quarter responded to the third dose of vaccine. The antibody response rates were lower during active treatment and in patients with a recent exposure (<12 months prior to vaccination) to anti-CD20 therapy. This trial was registered at www.clinicaltrials.gov as #NCT04862806.

Safety and efficacy of the BNT162b mRNA COVID-19 vaccine in patients with chronic lymphocytic leukemia.

Patients with chronic lymphocytic leukemia (CLL) have a suboptimal humoral response to vaccination. Recently, BNT162b2, an mRNA COVID-19 vaccine with a high efficacy of 95% in immunocompetent individuals, was introduced. We investigated the safety and efficacy of the BNT162b2 mRNA COVID-19 vaccine in patients with CLL from nine medical centers in Israel, Overall 400 patients were included, of whom 373 were found to be eligible for the analysis of antibody response. The vaccine appeared to be safe and only grade 1-2 adverse events were seen in 50% of the patients. Following the second dose, an antibody response was detected in 43% of the cohort. Among these CLL patients, 61% of the treatment-na ve patients responded to the vaccine, while responses developed in only 18% of those with ongoing disease, 37% of those previously treated with a BTK inhibitor and 5% of those recently given an anti-CD20 antibody. Among patients treated with BCL2 as monotherapy or in combination with anti-CD20, 62% and 14%, respectively, developed an immune response. There was a high concordance between neutralizing antibodies and positive serological response to spike protein. Based on our findings we developed a simple seven-factor score including timing of any treatment with anti-CD20, age, treatment status, and IgG, IgA, IgM and hemoglobin levels. The sum of all the above parameters can serve as a possible estimate to predict whether a given CLL patient will develop sufficient antibodies. In conclusion, the BNT162b2 mRNA COVID-19 vaccine was found to be safe in patients with CLL, but its efficacy is limited, particularly in treated patients.

Willingness and concerns of transfusion-dependent hematological patients toward the option of home transfusion therapy.

BACKGROUND: One of the main obstacles of providing home-based palliative care to transfusion-dependent hematology patients is the lack of home transfusions services. While healthcare professionals are concerned with safety and cost of home transfusions, the attitude of the patients toward home transfusions are mostly unknown. AIM: To obtain quantitative data regarding the willingness and concerns of transfusion-dependent patients with hematological diseases toward the option of home transfusions. DESIGN: A cross sectional survey including a self-administered questionnaire in one of the three main spoken languages in Israel was administered to patients in 17 hospital hematology outpatient clinics between May 2019 and March 2020. RESULTS: About 52% of 385 patients that participated in the survey preferred home transfusions to hospital transfusions. Gender, age, education, or type of disease were not associated with preference for home transfusions, nor were hospital location or its size. The likelihood to prefer home transfusions was significantly higher among the Hebrew-speakers and those who had not experienced adverse effects previously. The most significant factor associated with preference of home transfusions was a perceived negative effect of hospital-based transfusion on quality of life. The main reason to reject home transfusions was fear of possible adverse effects and concerns over losing contact with the medical staff at the treating hospital. CONCLUSION: These data suggest that a significant portion of transfusion-dependent patients in Israel view home transfusions as a preferred treatment option and that its successful implementation requires maintaining ongoing contact with the treating hospital.

Frontline treatment with the combination obinutuzumab ± chlorambucil for chronic lymphocytic leukemia outside clinical trials: Results of a multinational, multicenter study by ERIC and the Israeli CLL study group.

In recent years, considerable progress has been made in frontline therapy for elderly/physically unfit patients with CLL. The combination of obinutuzumab and chlorambucil (O-Clb) has been shown to prolong progression free survival (PFS, median PFS-31.5 months) and overall survival (OS) compared to chlorambucil alone. More recently, obinutuzumab given in combination with either ibrutinib or venetoclax improved PFS but not OS when compared to O-Clb. In this retrospective multinational, multicenter co-operative study, we evaluated the efficacy and safety of frontline treatment with O ± Clb in unfit patients with CLL, in a "real-world" setting. Patients with documented del (17p13.1)/TP53 mutation were excluded. A total of 437 patients (median age, 75.9 years; median CIRS score, 8; median creatinine clearance, 61.1 mL/min) were included. The clinical overall response rate was 80.3% (clinical complete and partial responses in 38.7% and 41.6% of patients, respectively). Median observation time was 14.1 months and estimated median PFS was 27.6 months (95% CI, 24.2-31.0). In a multivariate analysis, high-risk disease [del (11q22.3) and/or IGHV-unmutated], lymph nodes of diameter > 5 cm, obinutuzumab monotherapy and reduced cumulative dose of obinutuzumab, were all independently associated with shorter PFS. The median OS has not yet been reached and estimated 2-year OS is 88%. In conclusion, in a "real-world" setting, frontline treatment with O-Clb achieves PFS comparable to that reported in clinical trials. Inferior outcomes were noted in patients with del (11q22.3) and/or unmutated IGHV and those treated with obinutuzumab-monotherapy. Thus, O-Clb can be still considered as legitimate frontline therapy for unfit CLL patients with low-risk disease.

CD74 is a novel transcription regulator.

CD74 is a cell-surface receptor for the cytokine macrophage migration inhibitory factor. Macrophage migration inhibitory factor binding to CD74 induces its intramembrane cleavage and the release of its cytosolic intracellular domain (CD74-ICD), which regulates cell survival. In the present study, we characterized the transcriptional activity of CD74-ICD in chronic lymphocytic B cells. We show that following CD74 activation, CD74-ICD interacts with the transcription factors RUNX (Runt related transcription factor) and NF-κB and binds to proximal and distal regulatory sites enriched for genes involved in apoptosis, immune response, and cell migration. This process leads to regulation of expression of these genes. Our results suggest that identifying targets of CD74 will help in understanding of essential pathways regulating B-cell survival in health and disease.

Low-dose fludarabine and cyclophosphamide combined with standard dose rituximab (LD-FCR) is an effective and safe regimen for elderly untreated patients with chronic lymphocytic leukemia: The Israeli CLL study group experience.

Chronic lymphocytic leukemia (CLL) is a disease of elderly patients. The fludarabine, cyclophosphamide, and rituximab (FCR) regimen is considered the treatment of choice for young fit patients with CLL; however, this combination is toxic for older patients. At the time this study was first planned and initiated, there was no standard chemo-immunotherapy regimen regarded as standard therapy for the less fit elderly patient with CLL. Here, we conducted a single-arm, phase II trial to examine the efficacy and safety of lower-dose fludarabine and cyclophosphamide combined with a standard dose of rituximab (LD-FCR) in elderly patients with previously untreated CLL. Forty patients received LD-FCR and were included in the efficacy analysis. Two patients treated with FC alone were only included in the safety analysis. The median age was 72.7 years (range, 65.0 to 85.0). The overall response and complete response rates were 67.5% and 42.5%, respectively. Median progression-free survival (PFS) was 35.5 months (95% CI, 29.27-41.67). Two patients (4.8%) died during the study period. Hematological toxicities and infections were the most common complications encountered; grade 3 to 4 treatment-related neutropenia occurred in 20 (47.6%) patients. During the entire study follow-up, 26 patients (61.9%) had all grades of infection including six (14.3%) with neutropenic fever and eight (19%) with grade 3 to 4 non-neutropenic infections. In conclusion, LD-FCR is an effective and relatively safe regimen for previously untreated patients with CLL. It has the advantage of being both "time and cost limited" and, even in the era of novel agents, can still be considered when planning treatment for elderly patients without high-risk biomarkers. However, recent results in fit elderly patients using the combination of bendamustine and rituximab which have achieved longer PFS with good safety profile must be taken into consideration in this regard.

A new risk model to predict time to first treatment in chronic lymphocytic leukemia based on heavy chain immunoparesis and summated free light chain.

BACKGROUND: Chronic lymphocytic leukemia (CLL) is frequently accompanied by immune dysregulation. AIMS: In this multicenter prospective study, we investigated whether heavy + light chains (HLC: IgGκ, IgGλ, IgAκ, IgAκ, IgMκ, IgMλ) and IgG subclasses (IgG1, IgG2, IgG3, and IgG4) could be used as novel prognostic markers of immunoparesis in 105 treatment-naïve patients with CLL. RESULTS: Heavy + light chains immunoparesis of ≥1, ≥2, and ≥3 isotypes was evident in 74 (70%), 58 (55%), and 36 (34%) patients, respectively. Severe HLC immunoparesis was identified in 40 (38%) patients. Of the IgG subclasses, IgG1 and IgG2 were most frequently suppressed, affecting 46 (44%) and 36 (34%) patients, respectively; 63 (60%) patients had low levels of at least one IgG subclass. In multivariate analysis, severe HLC immunoparesis (hazard ratio [HR]: 36.5; P = .010) and ΣFLC ≥ 70 mg/L (HR: 13.2; P = .004) were the only factors independently associated with time to first treatment (TTFT). A risk model including these variables identified patients with 0, 1, and 2 risk factors and significantly different TTFT (P < .001). Patients with two factors represented an ultra-high-risk group with a median TTFT of only 1.3 months. CONCLUSION: The above findings demonstrate the potential for the use of HLC immunoparesis, together with sFLC measurements, as future prognostic biomarkers in CLL.

Characteristics, management and outcome of DLBCL patients, presenting with simultaneous systemic and CNS disease at diagnosis: A retrospective multicenter study.

The incidence of systemic diffuse large B cell lymphoma (DLBCL) concurrently involving the central nervous system (CNS) at diagnosis, is very low and data regarding the clinical course of these patients are scarce. We investigated characteristics, efficacy of treatment regimens including consolidative autologous stem cell transplantation and outcome of patients presenting with concomitant systemic and CNS DLBCL. The records of 44 patients, diagnosed between 2004 and 2017, who fulfilled the inclusion criteria, were retrospectively reviewed. CNS involvement was diagnosed as solely parenchymal in 41%, solely leptomeningeal in 43%, and paranchymal with leptomeningeal in 11% of the patients. Induction regimens were anthracycline-based combined with high-dose methotrexate (HD-MTX) in 80% (n = 35) of patients, anthracycline-based combined with intrathecal MTX in 3, cytarabine-based (without antracyclines) in 2, HD-MTX in 1 and palliative in three. Five of 41 patients treated with chemotherapy died of treatment-related toxicity, all due to infections. Nineteen patients had consolidative autologous transplantation. Overall response rate following induction was 80% (complete responses 66% and partial responses 15%). All relapses (n = 11) occurred within less than 2 years. Within a median follow-up of 26.8 months, 3-years projected overall survival (OS) and progression free survival rates for the entire cohort were 56% ± 8.3 and 42% ± 8.9, respectively. In multivariate analysis, RCHOP-HD MTX-based induction [HR = 0.228, (0.054-0.964)], administration of 3.5 g/m2 MTX [HR = 0.735 (0.620-0.871)], and attaining CR following induction [HR = 0.185, (0.051-0.667)] predicted longer OS. RCHOP-HD MTX can provide prolonged remissions in DLBCL patients presenting with concomitant systemic and CNS involvement whereas role of autograft remains uncertain.

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

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

Outcomes of second-line treatment after fludarabine cyclophosphamide and rituximab in patients with chronic lymphocytic leukemia outside clinical trials.

OBJECTIVE: To evaluate disease characteristics and long-term outcomes in patients requiring second-line treatment following fludarabine, cyclophosphamide, and rituximab (FCR), for relapsed/refractory disease (R/R), or following discontinuation due to toxicities. METHOD: A retrospective analysis of 126 chronic lymphocytic leukemia patients treated with frontline FCR: 63 received second-line treatment (41 relapsed, nine refractory [SD/PD], 13 prior toxicity). Time to next treatment (TTNT) was calculated from beginning FCR to initiation of second-line therapy. Overall and event-free survival was calculated from initiation of salvage treatment (OS2/EFS2). RESULTS: Median follow-up for the entire cohort was 67 and 37 months from second-line therapy. TTNT < 24 months was associated with shorter OS2 and EFS2 similar to those observed with primary refractory disease (OS2 19 and 23 months; EFS2 12 and 9 months for TTNT < 24 months and SD/PD, respectively). TTNT ≥ 24 months (71% chemotherapy-based second-line), had longer OS2 and EFS2 (48 and 20 months). Among the 13 patients receiving second-line therapy after discontinuing FCR due to toxicity EFS2 was 41 months (59 months from initiation of FCR). CONCLUSION: With limitations of sample size and treatment heterogeneity, patients progressing <24 months following FCR have poor outcomes, similar to refractory patients, while longer remissions are indicative of a chemoimmunotherapy sensitive disease. Patients who discontinue FCR for toxicities may achieve excellent outcomes with subsequent treatment.

[THE ROLE OF THE PLANT ARTEMISIA IN SURVIVAL AND INDUCTION OF APOPTOSIS OF B CELLS IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL)].

BACKGROUND: The cytotoxic effect of plants such as green tea and turmeric (curcumin) on B chronic lymphocytic leukemia (CLL) cells has been established. The plant Artemisia has been used in China for anti-cancer and anti-malaria applications. In Israel, Artemisia absinthium ("the Chiba") is used to release abdominal pain. In attempts to evaluate the cytotoxic effect of this plant in CLL cells, we prepared a decoction of Artemisia leaves and after filtration used it as an inducer of apoptosis of B CLL cells. METHODS: CLL cells were collected from 7 patients in different stages of the disease. Apoptosis was measured using an annexin based flow cytometry assay. RESULTS: First a viability test showed that 100µl/106 cells was the most effective dilution for killing up to 70% cells after 48 hours of incubation. In these conditions Artemisia induced approximately 75% apoptosis in comparison to 32% in the cultures without Artemisia. CONCLUSIONS: We concluded that decoction of Artemisia absinthium is a potent inducer of in vitro apoptosis of CLL cells. Our results provide a laboratory basis for further clinical application.

Characteristics of primary splenic diffuse large B-cell lymphoma and role of splenectomy in improving survival.

BACKGROUND: Primary splenic diffuse large B-cell lymphoma (PS-DLBCL), an uncommon type of non-Hodgkin lymphoma, has been investigated only in small patient series before the rituximab era. The therapeutic role of splenectomy in addition to immunochemotherapy is unknown. METHODS: The databases of 7 medical centers in Israel were searched for patients diagnosed with PS-DLBCL in 1982-2013, and clinical, treatment, and outcome data were collected for 87 patients. The mean patient age was 59.6 years; 57.5% were male. RESULTS: Patients presented with abdominal pain (81%), B symptoms (59%), splenomegaly (84%), splenic masses (97%), and high lactate dehydrogenase (LDH) levels (84%); 61% had stage I or II disease. The diagnosis was made with core-needle biopsy in 46 patients and with diagnostic splenectomy in 39 patients. Eighty patients (92%) were treated with cyclophosphamide, doxorubicin, vincristine, and prednisone; 68 (78%) received rituximab. A complete response was achieved in 67 patients (77%), and a partial response was achieved in 8 (9%). At 5 years, the overall survival (OS) rate was 77%, and the progression-free survival (PFS) rate was 67%. When patients were stratified by splenectomy at diagnosis, the OS rates were 91% for splenectomized patients and 68% for nonsplenectomized patients (P = .08), and the PFS rates were 85% and 55%, respectively (P = .02). The respective values for the subgroup with early-stage disease were 96% and 63% for OS (P = .009) and 90% and 51% for PFS (P = .01). In a multivariate analysis, a low Eastern Cooperative Oncology Group performance status and splenectomy independently predicted better PFS (P < .03). CONCLUSIONS: Patients with PS-DLBCL usually present with abdominal pain, high LDH levels, and a splenic mass. This study shows for the first time that splenectomy at diagnosis improves survival, specifically in patients with early-stage disease.

Efficacy and safety of front-line therapy with fludarabine-cyclophosphamide-rituximab regimen for chronic lymphocytic leukemia outside clinical trials: the Israeli CLL Study Group experience.

This study aimed to evaluate the efficacy and safety of the fludarabine-cyclophosphamide-rituximab regimen for young physically fit patients with chronic lymphocytic leukemia in the "real-life" setting. We specifically focused on the impact of dose reduction on patient outcomes. The patient cohort consisted of 128 patients with chronic lymphocytic leukemia (≤ 70 years) treated at 10 Israeli centers with front-line fludarabine-cyclophosphamide-rituximab. We defined reduced chemotherapy as two-thirds or less of the total indicated dose. Patients treated with rituximab were divided into two groups and compared: those who received full dosages of 375 mg/m(2) or 500 mg/m(2), and patients given less than six cycles with either dose. Overall and clinical complete response rates (92.8% and 70.4%), as well as toxicities and overall survival (median not reached at 6 years), were similar to other reported clinical trials, but progression-free survival was shorter (42.5 months). Almost 50% of patients had some dose reduction of chemotherapy, 21% receiving less than two-thirds of the indicated dose, while close to 30% did not complete six cycles of rituximab. Reduced doses of chemotherapy and rituximab were independently associated with shorter progression-free survival (hazard ratio 3.6, P<0.0001 for reduced chemotherapy; hazard ratio 2.5, P=0.003 for incomplete-treatment with rituximab). Achieving a complete response was associated with longer overall survival but was not linked to the given dose of chemoimmunotherapy. In younger physically fit patients, front-line fludarabine-cyclophosphamide-rituximab therapy in the "real-life" setting achieves long remissions (albeit shorter than in clinical trials) and prolonged overall survival. However, dose reductions are commonly administered and may impact outcome.

Serum immunoglobulin levels at diagnosis have no prognostic significance in stage A chronic lymphocytic leukemia: a study of 1113 cases from the Israeli CLL Study Group.

OBJECTIVES: Hypogammaglobulinemia, commonly encountered in chronic lymphocytic leukemia (CLL), is one of the main causes of morbidity and mortality; however, its prognostic significance in patients diagnosed in early stages of disease remains uncertain. The aim of this study was to evaluate the predictive power of hypogammaglobulinemia at Bonet stage A. METHODS: Using the database of the Israeli CLL Study Group, we analyzed the relationship between low serum levels of IgG, IgA, and IgM; the presence of paraproteinemia, as well as other well-recognized prognostic markers in CLL; and time to first treatment (TTT) and overall survival. A total of 1113 patients consecutively diagnosed during the last 25 yrs with Binet stage A CLL were evaluated, and baseline information on serum immunoglobulin levels was found in 857 of the cases. RESULTS: Overall survival times correlated with age >65 yr, male gender, the presence of lymphadenopathy, high serum beta 2-microglobulin (b2m), CD38 and ZAP-70 expression, but not with low levels of immunoglobulin or the presence of paraproteinemia. By univariate analysis, patients with low IgA levels had a shorter TTT; however, on multivariate analysis, the presence of lymphadenopathy (P 0.02), b2m (P 0.04), CD38 (P < 0.001), and ZAP-70 (P < 0.001) was the only laboratory parameters with prognostic significance. CONCLUSIONS: In our cohort of patients with early-stage CLL, baseline hypogammaglobulinemia and the presence of paraproteinemia were not found to correlate with prognosis.

Richter's transformation to diffuse large B-cell lymphoma: a retrospective study reporting clinical data, outcome, and the benefit of adding rituximab to chemotherapy, from the Israeli CLL Study Group.

Richter's syndrome (RS) is the rare development of an aggressive lymphoid malignancy in a patient with pre-existing chronic lymphocytic leukemia (CLL). Data on RS is sparse and mostly derived from case reports or small series of patients and only a few larger cohorts have been published. The purpose of this large retrospective study was to summarize our national experience with RS in CLL, examine possible risk factors, and analyze relevant demographic, laboratory and clinical parameters, including results of therapy and outcome. We first evaluated data obtained from 119 patients with RS diagnosed during 1971-2010 from 12 medical centers in Israel. The final cohort summarized consisted of 81 patients with RS who developed only diffuse large B-cell lymphoma (DLBCL) after exclusion all cases with insufficient data and those who were not DLBCL. Median overall survival from time of diagnosis of RS was 8 months; after applying the Richter score, patients could be stratified into three prognostic groups, while all other clinical and laboratory parameters evaluated had no prognostic significance. Prior therapy for CLL had no impact on RS survival (P = 0.8) and patients with therapy "naïve" RS and those who had already received chemotherapy prior to developing RS, had the same survival. The addition of rituximab to chemotherapy for RS improved 2 years overall survival from 19% in the chemotherapy alone arm to 42% (P value of 0.001). Although prognosis of patients with RS remains dismal, this retrospective observation provides support for the use of chemo-immunotherapy in DLBCL-RS.

The cytokine midkine and its receptor RPTPζ regulate B cell survival in a pathway induced by CD74.

Lasting B cell persistence depends on survival signals that are transduced by cell surface receptors. In this study, we describe a novel biological mechanism essential for survival and homeostasis of normal peripheral mature B cells and chronic lymphocytic leukemia cells, regulated by the heparin-binding cytokine, midkine (MK), and its proteoglycan receptor, the receptor-type tyrosine phosphatase ζ (RPTPζ). We demonstrate that MK initiates a signaling cascade leading to B cell survival by binding to RPTPζ. In mice lacking PTPRZ, the proportion and number of the mature B cell population are reduced. Our results emphasize a unique and critical function for MK signaling in the previously described MIF/CD74-induced survival pathway. Stimulation of CD74 with MIF leads to c-Met activation, resulting in elevation of MK expression in both normal mouse splenic B and chronic lymphocytic leukemia cells. Our results indicate that MK and RPTPζ are important regulators of the B cell repertoire. These findings could pave the way toward understanding the mechanisms shaping B cell survival and suggest novel therapeutic strategies based on the blockade of the MK/RPTPζ-dependent survival pathway.

Significance of bone marrow reticulin fibrosis in chronic lymphocytic leukemia at diagnosis: a study of 176 patients with prognostic implications.

BACKGROUND: Bone marrow (BM) biopsies from patients with chronic lymphocytic leukemia (CLL) may show reticulin fibrosis at diagnosis, but its significance remains unclear. This study sought to assess the prognostic impact of BM reticulin fibrosis in patients with previously untreated CLL. METHODS: Data was reviewed from untreated CLL patients in the national Israel CLL database, followed during 1987 to 2012. All bone marrow biopsies were graded for reticulin fibrosis using a modified scoring system containing 4 grades (0-3), based on the European consensus report. Grade of reticulin fibrosis was correlated with overall survival (OS), outcome, and a number of well-recognized prognostic factors for CLL. RESULTS: The final cohort included 176 patients (122 males and 51 females). Median age was 63 years (range, 32-86 years) and the 5-year OS was 77.1%. Grade of BM reticulin fibrosis correlated with OS (P < .0001) and mortality (P = .001), and separated patients into 2 groups with different survival curves. Advanced reticulin fibrosis (grades 2-3) was associated with thrombocytopenia (platelet counts of < 100,000/mm(3) ) (P = .025), anemia (P = .018), elevated ß2-microglobulin < 4000 µg/mL (P = .048), and the presence of 11q deletion (P = .0015). CONCLUSIONS: There was a significant correlation between poor survival and grade of BM reticulin fibrosis. This staining procedure is easy to perform and can readily be added routinely when examining BM biopsies in CLL, because the findings do have prognostic implications.