Characterization of the input material quality for the production of tisagenlecleucel by multiparameter flow cytometry and its relation to the clinical outcome.

Tisagenlecleucel (tisa-cel) is a CD19-specific CAR-T cell product approved for the treatment of relapsed/refractory (r/r) DLBCL or B-ALL. We have followed a group of patients diagnosed with childhood B-ALL (n = 5), adult B-ALL (n = 2), and DLBCL (n = 25) who were treated with tisa-cel under non-clinical trial conditions. The goal was to determine how the intensive pretreatment of patients affects the produced CAR-T cells, their in vivo expansion, and the outcome of the therapy. Multiparametric flow cytometry was used to analyze the material used for manufacturing CAR-T cells (apheresis), the CAR-T cell product itself, and blood samples obtained at three timepoints after administration. We present the analysis of memory phenotype of CD4/CD8 CAR-T lymphocytes (CD45RA, CD62L, CD27, CD28) and the expression of inhibitory receptors (PD-1, TIGIT). In addition, we show its relation to the patients' clinical characteristics, such as tumor burden and sensitivity to prior therapies. Patients who responded to therapy had a higher percentage of CD8+CD45RA+CD27+ T cells in the apheresis, although not in the produced CAR-Ts. Patients with primary refractory aggressive B-cell lymphomas had the poorest outcomes which was characterized by undetectable CAR-T cell expansion in vivo. No clear correlation of the outcome with the immunophenotypes of CAR-Ts was observed. Our results suggest that an important parameter predicting therapy efficacy is CAR-Ts' level of expansion in vivo but not the immunophenotype. After CAR-T cells' administration, measurements at several timepoints accurately detect their proliferation intensity in vivo. The outcome of CAR-T cell therapy largely depends on biological characteristics of the tumors rather than on the immunophenotype of produced CAR-Ts.

Peripheral T-Cell Lymphomas Involving the Central Nervous System: A Report From the Czech Lymphoma Study Group Registry.

Introduction: We analyzed the incidence, risk factors of central nervous system (CNS) relapse, and outcome of CNS involvement in patients with peripheral T-cell lymphomas (PTCL) from the Czech Lymphoma Study Group Registry NiHiL (Clinical Trial gov. NCT03199066). Materials and Methods: Out of 1,040 patients with PTCL, we identified 29 patients (2.79%) with CNS involvement: 2 patients with primary CNS T cell lymphoma, 11 patients with CNS and systemic disease at diagnosis, and 16 patients (1.54%) at CNS relapse. The most common histology with CNS disease was PTCL, not otherwise specified. Progression-free survival (PFS) was defined as the time interval from diagnosis to progression or death. PFS-2 was defined as the interval from the date of a new relapse until the next relapse. Results: Patients with testicular involvement received intrathecal prophylaxis with methotrexate. High-dose methotrexate-based treatment was administered in 44.8% of patients with CNS disease. Median follow-up was 71.3 months. The difference between the median PFS of 1,027 patients without initial CNS disease (32.6 months) and 11 patients with initial CNS and systemic disease (4.8 months) was significant (p = 0.04). The difference between the median PFS2 in CNS relapses (10.1 months) and 493 relapses outside of CNS (9.1 months) was not significant (p = 0.6). Risk factors for CNS relapses included the following: involvement of more than one extranodal site (p = 0.008), soft tissue involvement (p = 0.003), testicular involvement (p = 0.046), and the presence of B symptoms (p = 0.035). The difference between the median OS of 1,027 patients without initial CNS disease (46.0 months) and 11 patients with initial CNS and systemic disease (18.2 months) was significant (p = 0.02). The median OS2 in CNS relapses was 11.8 months and that in relapses outside of CNS was 21.3 months. CNS involvement was not associated with a significantly worse OS compared to relapsed/refractory patients without CNS involvement (p = 0.1). Conclusions: The incidence of CNS disease at the time of diagnosis and at relapse in PTCL is low and usually associated with other systemic involvement. The prognosis of PTCL with initial CNS involvement is significantly worse when compared to patients without CNS disease at diagnosis. The outcome of CNS relapse is comparable with relapsed PTCL outside of CNS. The optimal treatment is not defined yet.

Circulating microRNAs in Cerebrospinal Fluid and Plasma: Sensitive Tool for Detection of Secondary CNS Involvement, Monitoring of Therapy and Prediction of CNS Relapse in Aggressive B-NHL Lymphomas.

Lymphoma with secondary central nervous system (CNS) involvement represents one of the most aggressive malignancies, with poor prognosis and high mortality. New diagnostic tools for its early detection, response evaluation, and CNS relapse prediction are needed. We analyzed circulating microRNAs in the cerebrospinal fluid (CSF) and plasma of 162 patients with aggressive B-cell non-Hodgkin's lymphomas (B-NHL) and compared their levels in CNS-involving lymphomas versus in systemic lymphomas, at diagnosis and during treatment and CNS relapse. We identified a set of five oncogenic microRNAs (miR-19a, miR-20a, miR-21, miR-92a, and miR-155) in CSF that detect, with high sensitivity, secondary CNS lymphoma involvement in aggressive B-NHL, including DLBCL, MCL, and Burkitt lymphoma. Their combination into an oncomiR index enables the separation of CNS lymphomas from systemic lymphomas or nonmalignant controls with high sensitivity and specificity, and high Receiver Operating Characteristics (DLBCL AUC = 0.96, MCL = 0.93, BL = 1.0). Longitudinal analysis showed that oncomiR levels reflect treatment efficacy and clinical outcomes, allowing their monitoring and prediction. In contrast to conventional methods, CSF oncomiRs enable detection of early and residual CNS involvement, as well as parenchymal involvement. These circulating oncomiRs increase 1-4 months before CNS relapse, allowing its early detection and improving the prediction of CNS relapse risk in DLBCL. Similar effects were detectable, to a lesser extent, in plasma.

Chimeric Antigen Receptor Based Cellular Therapy for Treatment Of T-Cell Malignancies.

T-cell malignancies can be divided into precursor (T-acute lymphoblastic leukemia/lymphoblastic lymphoma, T-ALL/LBL) and mature T-cell neoplasms, which are comprised of 28 different entities. Most of these malignancies are aggressive with rather poor prognosis. Prognosis of relapsed/refractory (R/R) disease is especially dismal, with an expected survival only several months after progression. Targeted therapies, such as antiCD30 immunotoxin brentuximab vedotin, antiCD38 antibody daratumumab, and anti-CCR4 antibody mogamulizumab are effective only in subsets of patients with T-cell neoplasms. T-cells equipped with chimeric antigen receptor (CAR-Ts) are routinely used for treatment of R/R B-cell malignancies, however, there are specific obstacles for their use in T-cell leukemias and lymphomas which are fratricide killing, risk of transfection of malignant cells, and T-cell aplasia. The solution for these problems relies on target antigen selection, CRISPR/Cas9 or TALEN gene editing, posttranslational regulation of CAR-T surface antigen expression, and safety switches. Structural chromosomal changes and global changes in gene expression were observed with gene-edited products. We identified 49 studies of CAR-based therapies registered on www.clinicaltrials.gov. Most of them target CD30 or CD7 antigen. Results are available only for a minority of these studies. In general, clinical responses are above 50% but reported follow-up is very short. Specific toxicities of CAR-based therapies, namely cytokine release syndrome (CRS), seem to be connected with the antigen of interest and source of cells for manufacturing. CRS is more frequent in antiCD7 CAR-T cells than in antiCD30 cells, but it is mild in most patients. More severe CRS was observed after gene-edited allogeneic CAR-T cells. Immune effector cell associated neurotoxicity (ICANS) was mild and infrequent. Graft-versus-host disease (GvHD) after allogeneic CAR-T cells from previous hematopoietic stem cell donor was also observed. Most frequent toxicities, similarly to antiCD19 CAR-T cells, are cytopenias. CAR-based cellular therapy seems feasible and effective for T-cell malignancies, however, the optimal design of CAR-based products is still unknown and long-term follow-up is needed for evaluation of their true potential.

Burkitt lymphoma-a retrospective analysis of data from the Registry of the Czech Lymphoma Study Group with external validation of the Burkitt lymphoma International Prognostic Index.

Burkitt lymphoma (BL) is a rare subtype of non-Hodgkin's lymphoma with an aggressive course. To refine the individual patient's prognosis, the International Prognostic Index for BL (BL-IPI) was recently developed and 4 risk factors (RF) were determined as optimal prognostic cut-off by multivariate analysis: age ≥40 years, lactate dehydrogenase >3× upper limit of normal, ECOG performance status ≥2, and central nervous system involvement. The BL-IPI distinguishes 3 prognostic groups, low (without RF), intermediate (1 RF), and high risk (2-4 RF), with significant differences in survival. The aim of the current project was to perform an external validation of the BL-IPI in 101 patients from the Registry of Czech Lymphoma Study Group diagnosed between 1999 and 2016 (median age, 45 years). The median follow-up was 50.4 months. The induction treatment included rituximab plus chemotherapy in 82% and chemotherapy alone in 18%. The overall response rate was 78% and the complete remission rate was 73%. According to BL-IPI, low/intermediate/high risk was present in 21/35/45% of patients, showing high similarity to the training BL-IPI US (United States) dataset (18/36/46%). There were significant differences in progression-free survival (PFS) and overall survival (OS) between patients with high vs. intermediate risk (PFS: hazard ratio 0.16, 95% confidence interval 0.08-0.31, p<0.0001; OS: hazard ratio 0.17, 95% confidence interval 0.09-0.35, p<0.0001) but not between patients with low vs. intermediate risk. The 3-year OS probability according to BL-IPI with low/intermediate/high risk was 96/76/59% in the BL-IPI training dataset vs. 95/85/45% in our external validation cohort; the 3-year PFS probability with low/intermediate/high risk was 92/72/53% in the BL-IPI training dataset vs. 95/85/42% in our cohort. In summary, our external validation of the BL-IPI confirmed a good separation of high-risk patients, who have a poor prognosis and for whom the new therapeutic approaches are needed; patients with low and intermediate risk had favorable clinical outcomes, and differences between these groups were not significant, likely due to a small number of patients.

The Impact of Various Culture Conditions on Human Mesenchymal Stromal Cells Metabolism.

In vitro and in vivo analyses are closely connected, and the reciprocal relationship between the two comprises a key assumption with concern to the conducting of meaningful research. The primary purpose of in vitro analysis is to provide a solid background for in vivo and clinical study purposes. The fields of cell therapy, tissue engineering, and regenerative medicine depend upon the high quality and appropriate degree of the expansion of mesenchymal stromal cells (MSCs) under low-risk and well-defined conditions. Hence, it is necessary to determine suitable alternatives to fetal bovine serum (FBS-the laboratory gold standard) that comply with all the relevant clinical requirements and that provide the appropriate quantity of high-quality cells while preserving the required properties. Human serum (autologous and allogeneic) and blood platelet lysates and releasates are currently considered to offer promising and relatively well-accessible MSC cultivation alternatives. Our study compared the effect of heat-inactivated FBS on MSC metabolism as compared to its native form (both are used as the standard in laboratory practice) and to potential alternatives with concern to clinical application-human serum (allogeneic and autologous) or platelet releasate (PR-SRGF). The influence of the origin of the serum (fetal versus adult) was also determined. The results revealed the key impact of the heat inactivation of FBS on MSCs and the effectiveness of human sera and platelet releasates with respect to MSC behaviour (metabolic activity, proliferation, morphology, and cytokine production).

Current Immunotherapy Approaches in Non-Hodgkin Lymphomas.

Non-Hodgkin lymphomas (NHLs) are lymphoid malignancies of B- or T-cell origin. Despite great advances in treatment options and significant improvement of survival parameters, a large part of NHL patients either present with a chemotherapy-refractory disease or experience lymphoma relapse. Chemotherapy-based salvage therapy of relapsed/refractory NHL is, however, capable of re-inducing long-term remissions only in a minority of patients. Immunotherapy-based approaches, including bispecific antibodies, immune checkpoint inhibitors and genetically engineered T-cells carrying chimeric antigen receptors, single-agent or in combination with therapeutic monoclonal antibodies, immunomodulatory agents, chemotherapy or targeted agents demonstrated unprecedented clinical activity in heavily-pretreated patients with NHL, including chemotherapy-refractory cases with complex karyotype changes and other adverse prognostic factors. In this review, we recapitulate currently used immunotherapy modalities in NHL and discuss future perspectives of combinatorial immunotherapy strategies, including patient-tailored approaches.

ß-Catenin-TCF/LEF signaling promotes steady-state and emergency granulopoiesis via G-CSF receptor upregulation.

The canonical Wnt signaling pathway is mediated by interaction of ß-catenin with the T-cell factor/lymphoid enhancer-binding factor (TCF/LEF) transcription factors and subsequent transcription activation of Wnt-target genes. In the hematopoietic system, the function of the pathway has been mainly investigated by rather unspecific genetic manipulations of ß-catenin that yielded contradictory results. Here, we used a mouse expressing a truncated dominant negative form of the human TCF4 transcription factor (dnTCF4) that specifically abrogates ß-catenin-TCF/LEF interaction. Disruption of the ß-catenin-TCF/LEF interaction resulted in the accumulation of immature cells and reduced granulocytic differentiation. Mechanistically, dnTCF4 progenitors exhibited downregulation of the Csf3r gene, reduced granulocyte colony-stimulating factor (G-CSF) receptor levels, attenuation of downstream Stat3 phosphorylation after G-CSF treatment, and impaired G-CSF-mediated differentiation. Chromatin immunoprecipitation assays confirmed direct binding of TCF/LEF factors to the promoter and putative enhancer regions of CSF3R. Inhibition of ß-catenin signaling compromised activation of the emergency granulopoiesis program, which requires maintenance and expansion of myeloid progenitors. Consequently, dnTCF4 mice were more susceptible to Candida albicans infection and more sensitive to 5-fluorouracil-induced granulocytic regeneration. Importantly, genetic and chemical inhibition of ß-catenin-TCF/LEF signaling in human CD34+ cells reduced granulocytic differentiation, whereas its activation enhanced myelopoiesis. Altogether, our data indicate that the ß-catenin-TCF/LEF complex directly regulates G-CSF receptor levels, and consequently controls proper differentiation of myeloid progenitors into granulocytes in steady-state and emergency granulopoiesis. Our results uncover a role for the ß-catenin signaling pathway in fine tuning the granulocytic production, opening venues for clinical intervention that require enhanced or reduced production of neutrophils.

The interval between progression and therapy initiation is the key prognostic parameter in relapsing diffuse large B cell lymphoma: analysis from the Czech Lymphoma Study Group database (NIHIL).

Relapsing diffuse large B cell lymphomas (rDLBCL) represent a heterogeneous disease. This heterogeneity should be recognized and reflected, because it can deform the interpretation of clinical trial results. DLBCL patients with the first relapse and without CNS involvement were identified in the Czech Lymphoma Study Group (CLSG) database. Interval-to-therapy (ITT) was defined as the time between the first manifestation of rDLBCL and the start of any treatment. The overall survival (OS) of different ITT cohorts (< 7 vs. 7-21 vs. > 21 days) was compared. In total, 587 rDLBCLs (51.8% males) progressed with a median of 12.8 months (range 1.6 to 152.3) since the initial diagnosis (2000-2017). At the time of relapse, the median age was 67 years (range 22-95). First-line therapy was administered in 99.3% of the patients; CHOP and anti-CD20 were given to 69.2% and 84.7% of the patients, respectively. The salvage immune/chemotherapy was administered in 88.1% of the patients (39.2% platinum-based regimen). The median ITT was 20 days (range 1-851), but 23.2% of patients initiated therapy within 7 days. The 5-year OS was 17.4% (range 10-24.5%) vs. 20.5% (range 13.5-27.4%) vs. 42.2% (range 35.5-48.8%) for ITT < 7 vs. 7-21 vs. > 21 days (p < 0.001). ITT was associated with B symptoms (p 0.004), ECOG (p < 0.001), stage (p 0.002), bulky disease (p 0.005), elevated LDH (p < 0.001), and IPI (p < 0.001). The ITT mirrors the real clinical behavior of rDLBCL. There are patients (ITT < 7 days) with aggressive disease and a poor outcome. Conversely, there are rDLBCLs with ITT ≥ 21 days who survive for a long time.

Rituximab maintenance significantly reduces early follicular lymphoma progressions in patients treated with frontline R-CHOP.

Twenty percent of patients with high-tumor-burden (HTB) follicular lymphoma (FL) develop progression/relapse of disease (POD) within 24 months of frontline immunochemotherapy. Unfortunately, about 50% of these patients die within 5 years since POD event. Rituximab maintenance was proven to reduce relapse rate in responding FL, but its role on preventing POD was not defined. We analyzed 1360 HTB-FL patients from the Czech Lymphoma Study Group registry treated with frontline rituximab-containing regimen. Of those, 950 cases received rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and achieved complete or partial remission: 712 patients received rituximab maintenance (MAINT) and 238 were a historical observational cohort (OBS). We have proposed a modified POD24 (mPOD24) endpoint for the chemosensitive patients calculated from the end-of-induction (EOI). Survival rates since EOI were as follows: 5-year overall survival (OS) 86.2% versus 94.5% in the OBS and MAINT groups, respectively (P < .001) and 5-year progression-free survival 58.5% (OBS) and 75.4% (MAINT) (P < .001). The Cox proportional hazards model showed a decrease in mPOD24 incidence in the MAINT group with the overall hazard rate reduced by 56% (hazard ratio = 0.44; P < .001). The cumulative incidence of mPOD24 was reduced from 24.1% in OBS to 10.1% in MAINT (P < .001). Comparison of non-mPOD24 cases showed OS similar to that in the general population. Rituximab maintenance given after R-CHOP resulted in a 2.4-fold reduction in mPOD24 incidence. Once the non-POD24 status is achieved, FL does not shorten the patients' life expectancy.

First-line therapy for T cell lymphomas: a retrospective population-based analysis of 906 T cell lymphoma patients.

Peripheral T cell lymphomas (PTLs) have a globally poor prognosis. The CHOP regimen shows insufficient efficacy; first-line consolidation with autologous stem cell transplantation (auto-SCT) is a promising strategy but has never been confirmed by randomized data. We analyzed retrospectively 906 patients diagnosed with PTL between 1999 and 2015. Chemotherapy was given to 862 patients, and 412 of them were < 60 years. In this subset, we compared induction with CHOP (n = 113) vs. CHOEP (n = 68) and tested auto-SCT (n = 79) vs. no SCT (n = 73) in the intent-to-treat analysis. The median age of the whole cohort at diagnosis was 60 years (range; 18-91); the median follow-up was 4.3 years (range; 0.1-17.8). A shorter overall survival (OS) was associated with the male gender, age ≥ 60 years, stage III/IV, performance status ≥ 2, bulky tumor ≥ 10 cm, and elevated LDH. CHOEP induction showed a better 5-year PFS (25.0% vs. 32.9%; p.001), and 5-year OS (65.6% vs. 47.6%; p.008) than CHOP. Auto-SCT compared to no SCT brought a 5-year OS of 49.2% vs. 59.5% (p.187). Auto-SCT did not influence the OS in low-risk or low-intermediate risk PTLs. The high-intermediate and high-risk IPIs displayed a worse 5-year OS in auto-SCT arm (17.7% vs.46.2%; p.049); however, 73.9% of the patients never received planned auto-SCT. Our population-based analysis showed the superiority of CHOEP over CHOP in first-line treatment. We confirm the 5-year OS of around 50% in PTLs undergoing auto-SCT. However, the intended auto-SCT could not be given in 73.9% of the high-risk PTLs.

Hematopoietic Stem Cell Transplantation From Haploidentical Donors in Aplasia After Cladribine/Cytarabine Chemotherapy for Refractory Acute Myeloid Leukemia or Myelodysplastic Syndrome.

INTRODUCTION: Survival rate of patients with chemorefractory acute myeloid leukemia (AML) or myelodysplastic syndrome with excess blasts (MDS-EB) is poor. Allogeneic hematopoietic cell transplantation (HCT) is the only potentially curative therapy in these patients. PATIENTS AND METHODS: We report a retrospective analysis of outcomes of therapy of 24 patients with AML or MDS-EB refractory to high-dose salvage chemotherapy or who had failed previous HCT, who received T-cell-replete HLA haploidentical HCT in aplasia after cladribine/cytarabine-based chemotherapy followed by reduced intensity or myeloablative conditioning. All patients had active disease before commencement of the treatment. RESULTS: Of the patients, 91.7% achieved complete remission (CR), whereas 2 patients (8.2%) died in aplasia. One-year relapse rate was 49.3%. Cumulative incidence of nonrelapse mortality (NRM) was 25.6%. In a subgroup of patients with HCT-comorbidity index score ≤ 3, NRM was 15.4%. Two-year overall survival and relapse-free survival were 30.6% and 22.6%, respectively. Incidence of grade 3 and 4 acute graft versus host disease was 21.3% and 8.3, respectively. CONCLUSION: We found that sequential therapy with HCT in aplasia after cladribine/cytarabine chemotherapy is feasible, results in high CR rates, and has acceptable toxicity profile; however, posttransplant relapse is common in patients treated with active disease.

Maintenance rituximab in newly diagnosed mantle cell lymphoma patients: a real world analysis from the Czech lymphoma study group registry†.

We analyzed 495 MCL patients from the Czech Lymphoma Study Group data registry. With the median follow-up of 4.4 years, 51.7% patients progressed or relapsed and 34.1% died. Five-year overall survival reached 65.3% and five-year progression free survival 44.1% of the patients. Maintenance rituximab (MR) after first line therapy improved overall and progression free survival compared to the patients under observation only (both p < .001). Elevated beta-2-microglobulin (p = .003), presence of systemic symptoms (p = .002), ECOG >0 (p = .003), age (p = .014), and MIPI (p < .001) were associated with MR failure. Patients who did not achieve complete remission have had two-fold higher risk of MR failure (p < .001). Autologous stem cell transplant reduced the risk of MR failure by 69% (p < .001). The MIPI and the beta-2-microglobulin were identified as independent predictors of MR failure (p = .02 and p = .03, respectively). Patients who relapsed/progressed on MR reached shorter OS calculated from the MR start compared to patients without failure (HR = 15.0; p < .001).

miR-150 downregulation contributes to the high-grade transformation of follicular lymphoma by upregulating FOXP1 levels.

Follicular lymphoma (FL) is a common indolent B-cell malignancy with a variable clinical course. An unfavorable event in its course is histological transformation to a high-grade lymphoma, typically diffuse large B-cell lymphoma. Recent studies show that genetic aberrations of MYC or its overexpression are associated with FL transformation (tFL). However, the precise molecular mechanisms underlying tFL are unclear. Here we performed the first profiling of expression of microRNAs (miRNAs) in paired samples of FL and tFL and identified 5 miRNAs as being differentially expressed. We focused on one of these miRNAs, namely miR-150, which was uniformly downmodulated in all examined tFLs (∼3.5-fold), and observed that high levels of MYC are responsible for repressing miR-150 in tFL by binding in its upstream region. This MYC-mediated repression of miR-150 in B cells is not dependent on LIN28A/B proteins, which influence the maturation of miR-150 precursor (pri-miR-150) in myeloid cells. We also demonstrated that low miR-150 levels in tFL lead to upregulation of its target, namely FOXP1 protein, which is a known positive regulator of cell survival, as well as B-cell receptor and NF-κB signaling in malignant B cells. We revealed that low levels of miR-150 and high levels of its target, FOXP1, are associated with shorter overall survival in FL and suggest that miR-150 could serve as a good biomarker measurable in formalin-fixed paraffin-embedded tissue. Overall, our study demonstrates the role of the MYC/miR-150/FOXP1 axis in malignant B cells as a determinant of FL aggressiveness and its high-grade transformation.

The influence of maintenance therapy of rituximab on the survival of elderly patients with follicular lymphoma. A retrospective analysis from the database of the Czech Lymphoma Study Group.

The rituximab maintenance (RM) therapy for follicular lymphoma is effective and clinically well tolerated, however there is limited data regarding this from the elderly segment of the population. This analysis was performed to evaluate the efficacy of RM in elderly patients 65 years of age and older and to assess the influence of the induction therapy with immunochemotherapy (R-CHEMO) on the treatment outcome in a real world setting. A total of 232 consecutive patients treated with first-line R-CHEMO and RM (RM1 group; n = 158) or observation (RM0 group; n = 74) were analyzed. The effect of which induction therapy (R-CHOP vs. R-CVP) and the response of the patients to the first-line therapy were also evaluated. The addition of RM improved the treatment results in elderly patients. The 5- year overall survival rate in patients receiving R-CHEMO + RM1 compared to patients receiving R-CHEMO + RM0, was 83.7% (95% CI 76.1-89%) and 64.3% (95% CI 51.8-74.3%), respectively, p = 0.0012. The induction therapy with R-CHOP was found to be more effective than R-CVP but it is necessary to point out higher age of patients in the R-CVP arm. The 5- year overall survival rate in patients using R-CHOP ± RM and R-CVP ± RM was 84.9% (95% CI 77.5-90%), and 65.0% (95% CI 50.1-76.4%), respectively, p = 0.0008. The patients who achieved CR + uCR after having received first-line therapy had better outcomes compared to patients in PR. The 5- year overall survival rate in uCR + CR patients treated with R-CHEMO + RM1 and PR patients treated with R-CHEMO + RM1 was 90.6% and 68.3%, respectively, p = 0.0019. Rituximab maintenance treatment in patients 65 years and older yielded improved survival rates in a real world clinical setting. The R-CHOP regimen seems to be a more effective induction agent than R-CVP but the outcome of less intensively treated patients with R-CVP + RM is also acceptable. The achievement of uCR + CR after first-line therapy is associated with a better outcome.

Potential loss of prognostic significance of minimal residual disease assessment after R-CHOP-based induction in elderly patients with mantle cell lymphoma in the era of rituximab maintenance.

Rituximab maintenance (RM) prolongs survival of elderly patients with mantle cell lymphoma (MCL). Persistent minimal residual disease (MRD) after induction repeatedly correlated with shorter progression-free survival (PFS). However, none of the published studies analyzed patients treated with RM. The main purpose was to analyze prognostic significance of MRD in the elderly patients with newly diagnosed MCL treated according to the recently published observational trial protocol (alternation of R-CHOP and R-cytarabine, 3 + 3 cycles, GovTrial number NCT03054883) at the centers that implemented RM. Minimal residual disease was evaluated by a EuroMRD standardized real-time PCR approach after 3 and 6 cycles of the induction therapy. Prognostic significance of MRD was analyzed in a subcohort of patients treated at the centers that implemented RM as a standard approach. Bone marrow proved to be a significantly more sensitive source for MRD detection than peripheral blood. In either compartment MRD (positive versus negative) after 3 or 6 cycles of the induction therapy did not correlate with PFS. The observed loss of prognostic significance of MRD after the R-CHOP-based induction appears to be a consequence of RM immune control over the residual lymphoma.

Combined treatment of primary vitreoretinal lymphomas significantly prolongs the time to first relapse.

BACKGROUND: Vitreoretinal lymphomas belong to the family of central nervous system (CNS) lymphomas. The optimal approach for the treatment of isolated primary vitreoretinal lymphoma is unclear because of the lack of large comparative clinical series. Combination of intravitreal and systemic chemotherapy is recommended in many reports. The aim of our retrospective study was to compare the survival rate and prognosis of patients with vitreoretinal lymphoma with and without CNS involvement. METHODS: Twenty patients with vitreoretinal lymphomas were observed between the years 2004and2016, 10 patients with primary vitreoretinal lymphoma and 10 with primary CNS lymphoma. To compare survival rates, we included 53 patients diagnosed with primary CNS lymphoma without vitreoretinal involvement between the years 2002and2011 from our haemato-oncology department. RESULTS: The 5-year survival rate was estimated 71% in patients with vitreoretinal lymphoma in our observation. Significantly longer 5-year overall survival (P˂0.01) was observed in patients with vitreoretinal lymphoma compared with patients with primary CNS lymphoma without vitreoretinal involvement. Progression-free survival was almost equal in both groups of patients with primary vitreoretinal lymphoma and primary CNS lymphoma (P=0.363). The relapse of lymphoma was frequent (50%-60%) with the median time to first relapse of 31 months. Combined treatment (local and systemic) in patients without CNS involvement significantly prolonged progression-free survival in our study (P˂0.05). CONCLUSION: Combined treatment of primary vitreoretinal lymphoma significantly delays the relapse of lymphoma compared with local therapy alone. Intraocular involvement brings significant positive prognostic value when overall survival is compared.

The incidence of biopsy-proven transformation in follicular lymphoma in the rituximab era. A retrospective analysis from the Czech Lymphoma Study Group (CLSG) database.

The aim of this study is to assess the incidence, risk factors, and outcome of biopsy-proven transformation in follicular lymphoma (FL) patients in the rituximab era. Transformation was analyzed in 1233 patients with initially diagnosed FL grades 1-3A, identified between 2002 and 2012 in the prospectively maintained Czech Lymphoma Study Group database. Only patients with histologically proven transformation (HT) were included. HT occurred in 58 cases at a median of 3.0 years from the initial FL diagnosis; the HT rate was 4% at 5 years. Transformation occurred most frequently at the first relapse (84% patients). Median OS from the HT was 2.5 years (95% CI 0.4-4.6) and 6-year OS with HT was shorter compared to all FLs (60 vs. 83.9%; 95% CI). A bulky tumor (≥ 10 cm), increased lactate dehydrogenase, age ≥ 60 years, and International Prognostic Index (intermediate/high risk), but not Follicular Lymphoma International Prognostic Index, were associated with transformation (p < 0.05). In the first line, 70% of patients received rituximab (including 36% rituximab maintenance), 57% CHOP-like regimens, and 2.6% of patients were treated with fludarabine-based therapy, whereas 11% of patients were watched only. The patients treated with R-CHOP in the first line (n = 591) showed the transformation rate at 5 years of 4.23% (95% CI 2.52-5.93); subsequent rituximab maintenance (n = 276) vs. observation (n = 153) was associated with a lower transformation rate (p.033; HR 3.29; CI 1.10-9.82). The transformation rate seems to be lower than in previous series, which may be influenced by broad use of rituximab, but prognosis of HT developed during therapy continues to be poor.