Safety and efficacy of induction immunochemotherapy with rituximab, methotrexate, ifosfamide, and vincristine (R-MIV) in patients with primary CNS lymphoma including recent COVID-19 pandemic experience

Clinical data on primary central nervous system (CNS) lymphoma (PCNSL) patients is mostly generated from prospective studies, and many frail real-world patients are not included. Recently,the diagnosis and treatment of PCNSL patients was confounded by the COVID-19 pandemic. In particular, treatment with high-dose cytarabine was linked to increased risk of pneumonia and virus persistence. We report on outcome of the induction regimen R-MIV (rituximab, methotrexate, ifosfamide, and vincristine) involving intensive administration of high-dose methotrexate (3.5 g/m² ) with ifosfamide, every 2 weeks and rituximab once per week for six doses. The median age and performance status (PS) for 64 patients was 58 years and 2 (PS 3; 22%) respectively. The overall response rate by magnetic resonance imaging/computed tomography (MRI/CT) was 73% (n = 46/63), with an additional 17.5% (n = 11/63) patients without measurable disease at baseline. Grade 3-4 haematological toxicity was low for R-MIV (neutropenia: 25% and thrombocytopenia: 1%). Three patients (4.7%) died from treatment-related toxicity. Co-existence of SARS-CoV-2 infection with cytomegalovirus reactivation and the varicella-zoster virus in two patients was fatal. Fifty patients (78%) were eligible for consolidation. Median progression-free and overall survival were not reached (median follow-up: 44 months). In conclusion, the R-MIV regimen is feasible in routine practice, effective and safe, even during the COVID-19 pandemic.

Early efficacy and safety of obinutuzumab with chemotherapy in previously untreated patients with follicular lymphoma: A real-world retrospective report of the Polish Lymphoma Research Group

BACKGROUND

The first-line obinutuzumab-based immunochemotherapy improves the outcome of patients with follicular lymphoma (FL) compared with rituximab-based regimens. However, infusion-related reactions occur in almost half of patients during the 1st obinutuzumab administration.

OBJECTIVES

The study aimed to evaluate the early effectiveness and safety of obinutuzumab-based induction regimens in a real-world setting.

MATERIAL AND METHODS

Outcomes of patients diagnosed with FL and treated with obinutuzumab between January 2020 and September 2021 were analyzed.

RESULTS

The study group included 143 treatment-naïve patients with FL. The median age was 52 years (range: 28-89 years); 45.1% of patients had a high-risk disease as assessed using the Follicular Lymphoma International Prognostic Index (FLIPI). Induction chemotherapy included: O-CVP (obinutuzumab, cyclophosphamide, vincristine, prednisolone) in 49.0% of patients, O-CHOP (O-CVP plus doxorubicin) in 28.7% and O-BENDA (obinutuzumab, bendamustine) in 22.4%. Complete response (CR) and partial response (PR) rates were 69.9% and 26.5%, respectively. There was no difference in response rates between different regimens (p = 0.309). Maintenance was started in 115 patients (85.2%). In the 1st cycle, obinutuzumab was administered as a single 1000-milligram infusion in 47.9% of patients, whereas in 52.1%, initial infusions were split over 2 days (100 mg/900 mg). Infusion-related reactions were reported only during the 1st administration of obinutuzumab in 9.1% of patients, with a similar incidence in those receiving the total dose on a single day or split over 2 days (p = 0.458). The most common adverse events were hematological. Five patients died from coronavirus disease 2019 (COVID-19).

CONCLUSION

The early responses to induction regimens and adverse events profile were similar for every type of induction treatment. The infusion-related reactions were rare and limited to the 1st dose of obinutuzumab.

Rituximab and Chemotherapy for Newly Diagnosed Follicular Lymphoma - Real World Report of Polish Lymphoma Research Group

Introduction: Follicular lymphoma (FL) is the most common type of indolent B cell lymphoma with a favorable prognosis in the majority of patients. The induction treatment is still based on rituximab and chemotherapy, though new anty-CD20 antibody and chemo-free regimen have been recently introduced. The aim of the study was to analyze the management, outcomes and determinants of prognosis of newly diagnosed patients with FL in real-world experience. Methods: Data of consecutive patients diagnosed with FL in 5 years period (2011 – 2015) in three oncohematoogical centers were reviewed. Variables were compared using Mann-Whitney or chi-squared test as appropriate, survival outpoints were calculated using Kaplan-Meier method. Results: One hundred eighty-one patients were included in the study. The median patients' age at diagnosis was 56.6 years. Low histological grade (G1-G2) was found in 62.1% of patients and advanced clinical stage in 77.0% of patients. ECOG 0 performance status was observed in 57.1% of patients. The median follow-up was 5.91 years. Initially, 31.5% of the patients were qualified to watch and wait strategy (W&W) and 84.0% of the whole patients' group received systemic treatment during the observation period. As induction treatment, 53.9% and 41.4% of patients received RCVP and RCHOP regimens, respectively; 39.8% received rituximab maintenance (RM) after first-line therapy. During follow-up, transformation to aggressive lymphoma occurred in 7.2% of patients. Median overall survival (OS) was not achieved, and median progression-free survival (PFS) was 8.28 years (95% CI; 7.35, NA), 19.6% of patients relapsed during 24 months from the start of the treatment (POD24). Median PFS for POD24 group was 1.1 years (95% CI; 0.56, 1.45) with a median OS longer than 8 years. ECOG 0, low PRIMAPI and no POD24 were found as determinants of longer PFS and OS. Conclusions: Our data from clinical practice showed that rituximab and chemotherapy is still an effective method of FL treatment resulting in survival more than 8 years from diagnosis in most patients. RCVP protocol followed with RM is a reasonable choice for the first-line therapy especially in low/intermediate group of patients. The prognosis was significantly worse in patients with POD24. Therefore, searching for precise initial clinical and biological markers is warranted and development therapies to improve prognosis of POD24 patients.

EZH2 Expression in Follicular Lymphoma Is Variable and Independent from the Progression of Disease Within 24 Months of First Treatment

BACKGROUND/AIM

Follicular lymphoma (FL) relapse within 24 months of the first immunochemotherapy (POD24) indicates more precisely poor overall survival and high risk of death. The aim of the study was to assess the potential value of POD24 in FL and describe the enhancer of zeste homolog 2 (EZH2) expression profile, in correlation with clinical/histopathological/immunophenotypical characteristics.

MATERIALS AND METHODS

This retrospective single-center study included 75 patients with FL treated under watch and wait (W&W) and immunochemotherapy regimens. All cases were immunohistochemically assessed: assays were performed for EZH2, CD10, BCL6, BCL2, MUM1, MYC and p53.

RESULTS

POD24 was independent of clinical/histopathological/immunohistochemical features and separated patients with inferior outcomes. EZH2 high expression was observed in high/low grade and follicular/diffuse FL patterns. BCL2-negative (p=0.042) and MUM1 (p=0.039), MYC (p<0.001), p53 (p<0.001) - positive cases had significantly higher EZH2 expression.

CONCLUSION

POD24 is currently the most useful tool for the identification of poor outlook patients. EZH2 is crucial in FL biology, but the value of its protein expression is limited as a prognostic factor.

PD1 distribution pattern, regardless of the cell origin, is an independent microenvironmental prognostic factor for progression-free survival in follicular lymphoma

Follicular lymphoma (FL) is a well-studied microenvironment-dependent hematological malignancy, but the crosstalk between various involved cell subtypes is still not fully understood. Recent promising results of immunotherapy in recurrent FL warrant the need for an in-depth analysis of the expression and role of immune system-related proteins in the FL microenvironment. Seventy-one patients with FL and available diagnostic paraffin blocks were enrolled in the retrospective analysis. Histopathological diagnoses were revised according to the World Health Organization recommendations. Patients were either observed (watch and wait/W&W group) or immediately treated with chemo(immuno)therapy regimens according to their clinical status. Immunohistochemical assessment of PD1, PDL1, CD4, CD8, CD163, CD68-KP1, CD68-PGM1 was performed. The scoring methods included both semi-quantitative estimation of positive cells and architectural pattern distribution. The differences between PD1 staining distribution and intensity were classified as intra/perifollicular vs. interfollicular/diffuse cells and presented bright vs. dim immunoreactivity, respectively. No statistically significant differences in the density distribution of the immunohistochemical stainings were found between W&W and chemo(immuno)therapy groups. Interfollicular/diffuse pattern of PD1 expression had significantly decreased progression-free survival when analyzing the whole cohort and patients on chemo(immuno)therapy (p = 0.014 and p = 0.07, respectively). The high dependence was not significant in the W&W group. PD1 positivity of cells did not correlate with CD4 or CD8 immunophenotype. Morphologically FL neoplastic cells were entirely PDL1 negative, but granular and membranous staining was detected in the FL microenvironment. In line with previous studies, PD1/PDL1 expression was predominantly localized in the FL microenvironment, indicating that FL cells might not be the direct target for anti-PDL1 therapy. However, we show that the localization of PD1 expression could be a viable progression-free survival biomarker for FL.

Clinicopathological characteristics and outcome of plasmablastic lymphoma patients: A single-center retrospective analysis

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Background: Plasmablastic lymphoma (PBL) is a rare CD20-negative lymphoma with an aggressive clinical course and short median survival ranging from 9 to 32 months. It is often associated with HIV infection but it also affects immunocompetent patients. Due to the rare occurrence most data comes from small, retrospective series. Methods: This is a retrospective single-center analysis of PBL patients (pts) referred to MSCNRIO between 2003-2019. Diagnosis was established according to the WHO 2017 classification criteria. Kaplan–Meier method was used for calculating overall survival (OS) and progression-free-survival (PFS) and the log-rank test for comparisons. Univariate analysis of prognostic factors was carried out. Results: 24 pts with a diagnosis of PBL were included. The median age at diagnosis was 54 years (range 29-90). 15 pts (63%) were men. LDH was elevated in 10 pts (41%). Stage III or IV was reported in 21 (87.5%) pts, IPI score of 3-5 in 12 (50%) and ECOG performance status > 1 in 7 pts (29%). 20 pts (83.3%) had extranodal involvement, including oropharynx (n = 12), gastrointestinal tract (n = 1), bone marrow (n = 7), skeletal bone (n = 9), central nervous system (n = 3), skin and subcutaneous tissue (n = 2). Only 3 pts (13%) were infected by HIV, 2 had history of immunosuppressive therapy. Pathologically, all cases were negative for CD20 and positive for CD38 or CD138 expression. Ki67 > 90% was noted in 16 cases (66%). 11 pts received CHOP chemotherapy, 3 pts - thalidomide- and 4 pts - bortezomib-based regimens, 1 was treated with both agents. 4 pts received different protocols; 1 pt received no treatment. CR was observed in 8 pts (33%), PR in 6 (25%) and no response in 10 (42%). 2 pts received ASCT in the 1st remission. 17 pts (71%) experienced relapsed/progressive disease. 16 pts died: 11 from disease progression, 2 from other neoplasm. With a median follow-up of 20 months (range 2-122) median OS was 21 months and 2-year OS rate was 46% (95%C.I 27%, 65%). 2-year PFS rate was 37% (95% C.I. 17%, 57%), with median PFS 12 months (range 0.7-105). On univariate analysis there was a trend for correlation of high IPI with PFS; (95%C.I 0.99-1.03, P= 0.08). Achieving CR significantly correlated with better OS (HR 5; 95% C.I. 1.41-17; P= 0.01)) and PFS (HR 5.1, 95%C.I. 1.4, 18; P= 0.004). Conclusions: Our results confirm other reported data on PBL. Patients in our cohort shared typical clinical features but majority of them were immunocompetent. PBL prognosis remains poor despite incorporating novel agents into treatment and requires new therapeutic approaches.

Significance of CD10 protein expression in the diagnostics of follicular lymphoma: A comparison of conventional immunohistochemistry with flow cytometry supported by the establishment of BCL2 and BCL6 rearrangements

INTRODUCTION

Histopathological examination and immunohistochemistry (IHC) with a crucial role of CD10 expression remain a standard diagnostic tool in follicular lymphoma (FL). The results of IHC CD10 detection with different primary antibodies are not fully reproducible, but some reports show that flow cytometry (FCM) can be a reliable method of CD10 identification.

METHODS

The aim of the study was to compare results of CD10 expression in FL by IHC and FCM including immunophenotypic features in the context of the BCL2 and BCL6 alterations.

RESULTS

Out of 76 histopathologically diagnosed FL, a group of 25 cases had simultaneously FCM. Immunohistochemically 77.6% of cases were CD10-positive with comparable and reproducible results to FCM. Differences between the FCM expression of CD5/CD10/CD11c/CD25/CD43 and BCL2 overexpression (BCL2(+)^higher ) correlated with the BCL2 and BCL6 rearrangements (R) status. Lack of CD10 expression corresponded with the absence of BCL2R and higher MUM1 expression by IHC results but had no clinical impact on the long-time outcomes.

CONCLUSIONS

Immunohistochemistry staining is a comparable method to FCM assessment in the evaluation of CD10 expression and diagnosis of FL. Fine-needle aspiration biopsy/FCM (FNAB/FCM) could be a useful tool for verifying FL diagnosis and CD10 detection. Despite its heterogeneity, FL has a characteristic immunophenotype. BCL2R and BCL6R FL cases differ mainly in levels of BCL2 and CD10 with CD43 co-expression; BCL2(+)^higher by FCM correlates with BCL2R. Moreover, FNAB plays an important role in material provision for supportive karyotyping and BCL2R, BCL6R assessed by FISH.

The outcome of high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements or NOS compared to DLBCL patients from a single institution

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Background: 2016 update of the WHO 2008 classification of lymphoid neoplasms introduced new categories of highly aggressive B lymphomas (BCL): high grade B lymphoma (HGBL) with MYC and BCL2 and/or BCL6 rearrangements (HGBLR) and HGBL not otherwise specified (NOS). The prognosis for HGBL is generally considered poor, the optimal therapy is unknown. Here we evaluated outcome after first line treatment in patients with a diagnosis of HGBLR, HGBL, NOS, and DLBCL at our institution. Methods: Medical records of 591 consecutive patients with aggressive BCL were evaluated, archived pathology reports and samples were reviewed, diagnosis revised if necessary according to 2016 update of WHO classification. We identified 16 cases of HGBLR (3%), 26 cases of HGBL, NOS (4%), and 565 cases of DLBCL (93%). Response to first line therapy, progression free survival (PFS), and overall survival (OS) were calculated and compared between these three entities. Results: DLBCL patients were treated with RCHOP between 2005-2012, HGBL patients were treated between 2005-2016 with RDAEPOCH (n = 31, 5%), RCHOP or other regimens. For the first line treatment in patients with DLBCL, HGBLR and HGBL NOS, the overall response/complete response rate was 92%/75%, 81%/56%, 93%/65%, respectively (p = NS). After a median (range) follow up of 42(1-155) months, median PFS and OS for DLBCL was not reached. For both HGBLR and HGLB, NOS patients median PFS was 10 months, median OS was 16 months. The HR for risk of progression in patients with HGBLR vs DLBCL and HGBL NOS vs DLBCL was 2.4 (1.1-4.7), p = 0.01 and 2.0 (1.1-3.5), p = 0.01. The HR for risk of death, for HGBLR vs DLBCL and HGLB NOS vs DLBCL was 2.59(1.32-5.07), p < 0.01 and 1.8(0.9-3.3), p = 0.08. The risk of progression and the risk of death in HGBLR vs HGBL, NOS was similar, for PFS: 1.08 (0.46- 2.5), p = NS for OS: 1.2 (0.5 -3,1) p = NS. Conclusions: Our data confirms reports by others on poor prognosis for patients with a diagnosis of HGBL with MYC and BCL2 and/or BCL6 rearrangements as well as HGBL, NOS with an increased risk of death and risk of progression compared to DLBCL patients. There was no difference in outcome between HGBL-R and HGBL, NOS patients in our series.