Double Hit and Double Expresser Diffuse Large B Cell Lymphoma Subtypes: Discrete Subtypes and Major Predictors of Overall Survival

Improved outcomes of localized diffuse large B-cell lymphoma at the Waldeyer ring in comparison to the sinonasal area in the rituximab era

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) of the head-and-neck area primarily involves the Waldeyer ring (WR) and sinonasal area (SN). However, the differential clinical outcomes between patients with WR-DLBCL and those with SN-DLBCL in the rituximab era remain unclear.

METHODS

To avoid confounding factors contributed by advanced DLBCL with WR and SN involvement, we assessed the clinical outcomes of patients with stage I/II WR-DLBCL and SN-DLBCL and compared them with those having corresponding stages of DLBCL in the lymph nodes but without other extranodal involvement (LN-DLBCL) in the same period. We compared the patients' clinical characteristics, treatment modalities, event-free survival (EFS), and overall survival (OS) among the three subgroups.

RESULTS

We analyzed 67, 15, and 106 patients with WR-DLBCL, SN-DLBCL, and LN-DLBCL, respectively, between January 2000 and December 2019. All patients received front-line rituximab-based regimens, and > 80% received rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone-based regimens. More patients with SN-DLBCL had revised International Prognostic Index (R-IPI) score 3 (27%) when compared with those with WR-DLBCL (7%) and those with LN-DLBCL (10%, p = 0.181). Patients with WR-DLBCL, LN-DLBCL, and SN-DLBCL had 5-year EFS and OS rates of 80.7%, 59.5%, and 41.9% (p = 0.021) and 83.7%, 70.8%, and 55.8% (p = 0.032), respectively. Compared to patients with LN-DLBCL, those with WR-DLBCL also had a significantly favorable 5-year EFS rate (p = 0.021) and 5-year OS rate (p = 0.023). Three of the 15 patients with SN-DLBCL experienced lymphoma recurrence in the brain after front-line treatment. In multivariate analyses, R-IPI scores of 1-2 and 3 served as significantly poor prognostic factors for patients with poor EFS and OS.

CONCLUSIONS

Compared to patients with LN-DLBCL, patients with WR-DLBCL receiving front-line rituximab-based treatments had favorable clinical outcomes; however, patients with SN-DLBCL had worse clinical outcomes. Further studies on molecular prognostic factors and treatment strategies for SN-DLBCL are warranted.

Targeting MYC-driven lymphoma: lessons learned and future directions

MYC plays a central role in tumorigenesis by orchestrating cell proliferation, growth and survival, among other transformation mechanisms. In particular, MYC has often been associated with lymphomagenesis. In fact, MYC overexpressing lymphomas such as high-grade B-cell lymphoma (HGBL) and double expressor diffuse large B-cell lymphomas (DLBCL), are considered addicted to MYC. In such a context, MYC targeting therapies are of special interest, as MYC withdrawal is expected to result in tumor regression. However, whether high MYC levels are always predictive of increased sensitivity to these approaches is not clear yet. Even though no MYC inhibitor has received regulatory approval to date, substantial efforts have been made to investigate avenues to render MYC a druggable target. Here, we summarize the different classes of molecules currently under development, which mostly target MYC indirectly in aggressive B-cell lymphomas, paying special attention to subtypes with MYC/BCL2 or BCL6 translocations or overexpression.

An immunohistochemical study of double-expressor lymphomas and its correlation with cell of origin

Background

Diffuse large B cell Lymphomas (DLBCL) that co express C MYC and BCL 2 are known as 'double expressor lymphomas' and are believed to have a worse prognosis than other diffuse large B cell lymphomas. This was a study to assess the frequency of double expressor lymphomas in our cohort of DLBCL.

Aims and Objectives

The aims of this study were to assess the frequency of double expression of C MYC and BCL 2 in cases of DLBCL and to correlate the same with clinicopathological parameters including cell of origin, namely germinal centre type versus non germinal centre type.

Materials and Methods

This was a retrospective observational study Immunostaining for MYC antibody and BCL2 were performed using the standard polymer/DAB technique. 40% for MYC and 50% for BCL2 were taken as cut off values.Chi square analysis was used to compare the variables, and a p value of less than 0.05 was taken as statistically significant.

Results

Of 40 cases studied, 11 (27.5%) were double expressors. There was no significant correlation of double expression with gender, site (nodal versus extra nodal), cell of origin namely germinal centre/non germinal centre types and Ki67 index when compared to the other group which did not show double expression.

Conclusions

Immunohistochemistry is a useful technique to detect double expressor lymphomas which are known to have an aggressive course. Cell of origin did not show significant correlation with double expression in our study.

Meta-Analysis of MS-Based Proteomics Studies Indicates Interferon Regulatory Factor 4 and Nucleobindin1 as Potential Prognostic and Drug Resistance Biomarkers in Diffuse Large B Cell Lymphoma

The prognosis of diffuse large B cell lymphoma (DLBCL) is inaccurately predicted using clinical features and immunohistochemistry (IHC) algorithms. Nomination of a panel of molecules as the target for therapy and predicting prognosis in DLBCL is challenging because of the divergences in the results of molecular studies. Mass spectrometry (MS)-based proteomics in the clinic represents an analytical tool with the potential to improve DLBCL diagnosis and prognosis. Previous proteomics studies using MS-based proteomics identified a wide range of proteins. To achieve a consensus, we reviewed MS-based proteomics studies and extracted the most consistently significantly dysregulated proteins. These proteins were then further explored by analyzing data from other omics fields. Among all significantly regulated proteins, interferon regulatory factor 4 (IRF4) was identified as a potential target by proteomics, genomics, and IHC. Moreover, annexinA5 (ANXA5) and nucleobindin1 (NUCB1) were two of the most up-regulated proteins identified in MS studies. Functional enrichment analysis identified the light zone reactions of the germinal center (LZ-GC) together with cytoskeleton locomotion functions as enriched based on consistent, significantly dysregulated proteins. In this study, we suggest IRF4 and NUCB1 proteins as potential biomarkers that deserve further investigation in the field of DLBCL sub-classification and prognosis.

Application of next-generation sequencing in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of invasive non-Hodgkin lymphoma. There is great heterogeneity in its molecular biological characteristics, clinical manifestations and prognosis. The use of rituximab has greatly improved the cure rate of DLBCL, but there are still 30% of patients with poor prognosis. In the era of precision medicine, the significance of molecular biology and genetic factors on the diagnosis, treatment and prognosis of patients has been found. Among these, next-generation sequencing technology plays an important role. This paper reviews the research progress of next-generation sequencing technology in the classification, diagnosis, prognosis and molecular targeted therapy of DLBCL.

Comparison of the Effectiveness and Safety of the Oral Selective Inhibitor of Nuclear Export, Selinexor, in Diffuse Large B Cell Lymphoma Subtypes

BACKGROUND

The SADAL study evaluated oral selinexor in patients with relapsed and/or refractory diffuse large B-cell lymphoma (DLBCL) after at least 2 prior lines of systemic therapy. In this post-hoc analysis, we analyzed the outcomes of the SADAL study by DLBCL subtype to determine the effects of DLBCL subtypes on efficacy and tolerability of selinexor.

PATIENTS AND METHODS

Data from 134 patients in SADAL were analyzed by DLBCL subtypes for overall response rate (ORR), overall survival (OS), duration of treatment response, progression-free survival, and adverse events rate.

RESULTS

ORR in the entire cohort was 29.1%, and similar in patients with germinal center (GCB) versus non-GCB DLBCL (31.7% vs. 24.2%, P = 0.45); transformed DLBCL showed a trend towards higher ORR than de novo DLBCL: 38.7% vs. 26.2% (P = 0.23). Despite similar prior treatment regimens and baseline characteristics, patients with DLBCL and normal C-MYC/BCL-2 protein expression levels had a significantly higher ORR (46.2% vs.14.8%, P = 0.012) and significantly longer OS (medians 13.7 vs. 5.1 months, hazard ratio 0.43 [95% CI, 0.23-0.77], P = 0.004) as compared with those whose DLBCL had C-MYC and BCL-2 overexpression. Among patients who had normal expression levels of either C-MYC or BCL-2 and baseline hemoglobin levels ≥ 10g/dL, ORR was 51.5% (n = 47), with median OS of 15.5 months and median PFS of 4.6 months. Similar rates of adverse events were noted in all subgroups.

CONCLUSIONS

Overall, single agent oral selinexor showed strong responses in patients with limited treatment alternatives regardless of germinal center B-cell type or disease origin.

Double-Expressor Phenotype (BCL-2/c-MYC Co-expression) of Diffuse Large B-Cell Lymphoma and Its Clinicopathological Correlation

Introduction Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease, the spectrum of which is increasing with time. The 2016 World Health Organization (WHO) update on hematopoietic tumors recognized a prognostic subgroup of DLBCL called double-expressor DLBCL. Double-expressor DLBCL is defined by the co-expression of c-MYC and BCL-2 by using immunohistochemical (IHC) studies. To our knowledge, very few studies have looked into the pathological features of this newly defined prognostic category of DLBCL; therefore, in this study we evaluated the frequency of the double-expressor phenotype of DLBCL and its association with other clinicopathological parameters. Methods We conducted a retrospective observational study in the Department of Histopathology, Liaquat National Hospital and Medical College, from November 2017 till December 2020. Pathological and clinical records were retrieved from departmental archives. All cases diagnosed as DLBCL were included in the study. More than 40% c-MYC expression in the presence of more than 50% BCL-2 expression was defined as double-expressor DLBCL. Results The mean age of the patients was 52.1±16.9 years. The mean Ki67 index was 73.0±17.0%. A total of 48.6% cases were of germinal center B-cell-like (GCB) subtype, and 59.6% cases were nodal. Double-expressor phenotype was noted in 35.8% of DLBCL cases. A significant association of double-expressor phenotype was noted with age, gender, Ki67 index and subtype of DLBCL. Double-expressor DLBCL had a higher mean age than non-double-expressor DLBCL. Similarly, double-expressor DLBCL had a higher Ki67 index. Moreover, double-expressor phenotype was associated with non-GCB subtype DLBCL. Conclusion We found a high proportion of double-expressor phenotype DLBCL in our population. Moreover, double-expressor phenotype DLBCL was associated with female gender, higher age, higher Ki67 and non-GCB subtype. The association of double-expressor DLBCL with a high Ki67 index and non-GCB subtype confers a poor prognostic significance of this variant of DLBCL, requiring more aggressive therapy.