Cases Of Diffuse Large B-cell Lymphoma Research Articles

Identification and Validation of a DNA Damage Repair-Related Signature for Diffuse Large B-Cell Lymphoma.

Background Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin's lymphoma in adults, whose prognostic scoring system remains to be improved. Dysfunction of DNA repair genes is closely associated with the development and prognosis of diffuse large B-cell lymphoma. The aim of this study was to establish and validate a DNA repair-related gene signature associated with the prognosis of DLBCL and to investigate the clinical predictive value of this signature. Methods DLBCL cases were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. One hundred ninety-nine DNA repair-related gene sets were retrieved from the GeneCards database. The LASSO Cox regression was used to generate the DNA repair-related gene signature. Subsequently, the level of immune cell infiltration and the correlation between the gene signature and immune cells were analyzed using the CIBERSORT algorithm. Based on the Genomics of Drug Sensitivity in Cancer (GDSC) database, the relationship between the signature and drug sensitivity was analyzed, and together with the nomogram and gene set variation analysis (GSVA), the value of the signature for clinical application was evaluated. Results A total of 14 DNA repair genes were screened out and included in the final risk model. Subgroup analysis of the training and validation cohorts showed that the risk model accurately predicted overall survival of DLBCL patients, with patients in the high-risk group having a worse prognosis than patients in the low-risk group. Subsequently, the risk score was confirmed as an independent prognostic factor by multivariate analysis. Furthermore, by CIBERSORT analysis, we discovered that immune cells, such as regulatory T cells (Tregs), activated memory CD4+ T cells, and gamma delta T cells showed significant differences between the high- and low-risk groups. In addition, we found some interesting associations of our signature with immune checkpoint genes (CD96, TGFBR1, and TIGIT). By analyzing drug sensitivity data in the GDSC database, we were able to identify potential therapeutics for DLBCL patients stratified according to our signature. Conclusions Our study identified and validated a 14-DNA repair-related gene signature for stratification and prognostic prediction of DLBCL patients, which might guide clinical personalization of treatment.

Genetic and phenotypic characterisation of HIV-associated aggressive B-cell non-Hodgkin lymphomas, which do not occur specifically in this population: diagnostic and prognostic implications.

The frequency of aggressive subtypes of B-cell non-Hodgkin lymphoma (B-NHL), such as high-grade B-cell lymphomas (HGBL) with MYC and BCL2 and/or BCL6 rearrangement (HGBL-DH/TH) or Burkitt-like lymphoma (BL) with 11q aberration, is not well known in the HIV setting. We aimed to characterise HIV-associated aggressive B-NHL according to the 2017 WHO criteria, and to identify genotypic and phenotypic features with prognostic impact. Seventy-five HIV-associated aggressive B-NHL were studied by immunohistochemistry (CD10, BCL2, BCL6, MUM1, MYC, and CD30), EBV-encoded RNAs (EBERs), and fluorescence in situ hybridisation (FISH) to evaluate the status of the MYC, BCL2, and BCL6 genes and chromosome 11q. The 2017 WHO classification criteria and the Hans algorithm, for the cell-of-origin classification of diffuse large B-cell lymphomas (DLBCL), were applied. In DLBCL cases, the frequencies of MYC and BCL6 rearrangements (14.9 and 27.7%, respectively) were similar to those described in HIV-negative patients, but BCL2 rearrangements were infrequent (4.3%). MYC expression was identified in 23.4% of DLBCL cases, and coexpression of MYC and BCL2 in 13.0%, which was associated with a worse prognosis. As for BL cases, the expression of MUM1 (30.4%) conferred a worse prognosis. Finally, the prevalence of HGBL-DH/TH and BL-like with 11q aberration are reported in the HIV setting. The phenotypic and genotypic characteristics of HIV-associated aggressive B-NHL are similar to those of the general population, except for the low frequency of BCL2 rearrangements in DLBCL. MYC and BCL2 coexpression in DLBCL, and MUM-1 expression in BL, have a negative prognostic impact on HIV-infected individuals.

INCIDENTAL PRIMARY PULMONARY DIFFUSE LARGE B-CELL LYMPHOMA

INCIDENTAL PRIMARY PULMONARY DIFFUSE LARGE B-CELL LYMPHOMA

S3393 Diffuse Large B Cell Lymphoma Presenting as Bleeding and Hypoalbuminemia: A Case Report

Introduction: Diffuse large B cell lymphoma (DLBCL) accounts for 38-57% of primary gastrointestinal (GI) lymphomas. Initial presentation can include nonspecific symptoms, such as weight loss, fatigue, and nausea. Imaging studies are typically nonspecific as well. Therefore, patients are commonly misdiagnosed or diagnosis is delayed. 20-30% of GI lymphomas are in the small intestine but are rarely in the jejunum. We present a rare case of jejunal DLBCL and illustrate the diagnostic difficulties. Case Description/Methods: A 49-year-old male presented with weeks of dizziness, dyspnea, hematochezia, and 30-pound unintentional weight loss over 4 months. Labs were notable for anemia and severe hypoalbuminemia (1.9 g/dL). Esophagogastroduodenoscopy and colonoscopy revealed diverticulosis and hemorrhoids, which were the presumed etiology of his symptoms. One month later, the patient presented similarly. Imaging demonstrated bilateral pulmonary emboli and intramural thickening of the jejunum. For worsening hypoalbuminemia (1.3 g/dL), the patient was scheduled for outpatient work-up. However, he presented again for acute GI bleed and severe anemia. Push enteroscopy revealed patchy mucosal changes in the jejunum and biopsies were consistent with DLBCL. The patient was started on chemotherapy and reported improvement in symptoms and resolution of his GI bleed. Discussion: Primary GI DLBCL is rarely found in the jejunum due to the lack of lymphoid tissue, making this case noteworthy. GI DLBCL is difficult to diagnose, since patients may be asymptomatic or present with nonspecific symptoms. Small intestinal DLBCL can present with GI bleeding, which can easily lead to a misdiagnosis of a diverticular or hemorrhoidal bleed. Imaging studies can be nonspecific and obtaining confirmation through biopsy can prove difficult due to its location, further complicating the diagnosis. One unique aspect of this case that led to the diagnosis was the severity of hypoalbuminemia. The patient was not malnourished, had no clinically apparent protein-losing enteropathy, and no proteinuria or liver failure, making underlying malignancy likely. Differential diagnoses of small bowel wall thickening on imaging is wide and includes infections, primary inflammatory processes such as IBD, and neoplastic lesions. DLBCL may have unusual clinical presentations, subtle laboratory findings and may not be easily diagnosed with initial imaging; thus, clinicians should remain vigilant of this possible diagnosis.

S1686 Primary Pancreatic Diffuse Large B Cell Lymphoma: A Rare and TreaTable Malignancy

Introduction: Pancreatic lymphoma comprise less than 1 % of pancreatic malignancies. Most common location of diffuse large B cell lymphoma (DLBCL) are lymph nodes. Clinical symptoms and imaging studies have significant similarity resulting in delayed diagnosis or early initiation of comfort care measures. It is important to determine the histology of pancreatic tumor given the differences in management and prognosis. Here we report a rare case of primary DLBCL arising from pancreas. Case Description/Methods: 62-year-old female with history of HTN and DM presented with 30 lbs unintentional weight loss epigastric abdominal pain and early satiety. CT abdomen with IV and oral contrast demonstrated pancreatic mass. Core biopsy of pancreatic head mass demonstrated infiltration by large atypical lymphoid cells with high N/C ratio, round nuclear contour, fine chromatin and variably prominent nucleoli (Figure A). Atypical mitosis and apoptosis seen in background. Lymphoma cells positive for CD 19, CD 20 (Figure B). Final diagnosis Large B cell lymphoma germinal center type. FISH for BCL 2, C MYC were normal ruling out possibility of double or triple hit lymphoma. Cancer antigen 19-9 at the time of diagnosis was within normal limits. FDG PET/CT prior to initiation of treatment showed main foci of increased tracer activity appears to be in the proximal body of the pancreas just medial to the stomach, measures greater than 4 cm in diameter, and has a maximum SUV of 11.86 (Figure C). Rituximab- Cyclophosphamide HydrOxyadriamycin Prednisone (R-CHOP) every 3 weeks initiated. After one cycle of R-CHOP reported significant improvement in epigastric pain and started gaining weight. She completed 6 cycles of R-CHOP. Post treatment FDG PET/CT complete resolution of upper abdominal lymph node mass (Figure D). She remains in remission for the past 1 year. Discussion: Our case is an example of successful biopsy and treatment with aim to cure pancreatic malignancy. Despite radiological differences between pancreas adenocarcinoma and lymphoma, it is crucial to obtain adequate tissue sampling during from pancreas to establish histological diagnosis prior to discussion of prognosis and treatment plan. In general, DLBCL germinal center type has a 5-year survival of 70% with R-CHOP. Differential diagnosis of pancreatic mass that confer better prognosis than adenocarcinoma include neuroendocrine tumor, solid pseudopapillary tumor and lymphoma. Therefore, it is important to obtain biopsy and direct therapy based on histology.Figure 1.: A: Core biopsy of pancreatic head mass demonstrated infiltration by large atypical lymphoid cells with high N/C ratio, round nuclear contour, fine chromatin and variably prominent nucleoli. B: Lymphoma cells positive for CD 19, CD 20. C: FDG PET/CT prior to initiation of treatment showed main foci of increased tracer activity appears to be in the proximal body of the pancreas just medial to the stomach, measures greater than 4 cm in diameter, and has a maximum SUV of 11.86. D: Post treatment FDG PET/CT complete resolution of upper abdominal lymph node mass.

S2227 A Rare Case of Primary Diffuse Large B Cell Lymphoma of the Colon

Introduction: Primary colorectal lymphomas are rare and account for 0.3% of all large intestinal malignancies, with Diffuse Large B-Cell Lymphoma (DLBCL) representing the most common subtype. We present a case of primary colonic DLBCL that was diagnosed after surgical resection of the sigmoid colon. Case Description/Methods: An 86-year-old White female with a past medical history of diverticulosis and atrial fibrillation presented to the emergency department complaining of abdominal cramping and rectal bleeding. Physical examination was significant for mild abdominal tenderness and vital signs revealed blood pressure of 151/83 mmHg. Laboratory investigations were significant for white blood cell count of 10.56 x 10^3 cells/uL and potassium 2.8 mmol/L. Abdominal and pelvic computed tomography with contrast revealed sigmoid colonic diverticulosis with interposition of colon between liver and right hemidiaphragm. The patient underwent colonoscopy that showed a stricture of benign intrinsic appearance in the sigmoid colon measuring 10 cm in diameter and 3 cm in length. Histological analysis of tissue biopsies taken at that time were only significant for mild to moderate colitis. After colonoscopy, she was taken for laparoscopic low anterior resection of the sigmoid colonic mass that was later converted to an open approach due to the size of the mass. After the incision was extended, the sigmoid colon was further mobilized and the uninvolved portions of the proximal rectum and descending colon were transected. After the sigmoid colon was removed and sent to pathology, the proximal rectum and descending colon were anastomosed with no air leaks identified. Pathology report of the surgical specimen later showed malignant lymphoma with transmural invasion and involvement of numerous adjacent pericolonic nodes with negative tumor margins. Immunostains revealed the tumor to be positive for BCL-2, BCL-6, CD10, and CD20 but negative for CD3 and BCL-1. High proliferative activity was discerned for KI-67 staining in 90% of tumor cells; all evidence supporting the diagnosis of DLBCL. After an uneventful postoperative period and clinical improvement, the patient was discharged to home for close follow-up. Discussion: Primary colonic lymphomas are rare and usually present with nonspecific symptoms. Although in the case discussed, the patient did not present with any obvious predisposing conditions for DLBCL, further data is necessary to determine other possible associations and develop a standardized treatment regimen.

S2150 Triangle of Lymphocytic Colitis, Epstein-Barr Virus, and Lymphoma: Is There Any Association?

Introduction: Epstein–Barr virus (EBV), is linked to range of lymphoproliferative lesions and malignant lymphomas of B-, T- and NK-cell origin. EBV-positive diffuse large B cell lymphoma (DLBCL) not otherwise specified is a variant of DLBCL seen in patients without known immunodeficiency or prior lymphoma. In few reports EBV infection was more commonly detected in colonic mucosa of patients with Microscopic Colitis (MC), but it remains unclear if this translates to higher incidence of lymphoma in this subgroup of people. Here, we describe a case of DLBCL in patient with MC associated with EBV infection in context of recent findings. Case Description/Methods: 77-year-old female with history of COPD, diabetes underwent colonoscopy for chronic diarrhea of 4-month duration. She suffered from 3-4 loose stools/day, and had normal celiac panel, fecal elastase, and infectious workup. Colonoscopy was unremarkable except for 4 mm Paris Is polyp in sigmoid colon removed with cold snare. On pathology, the random colon biopsies were positive for lymphocytic colitis along and polyp showed DLBCL (non-germinal center phenotype) along with positive EBV infection (Figure). Discussion: It is widely believed that overall risk of malignancy is not increased in MC. However, theoretically MC should increase risk of lymphoma as it is more likely to be associated with oncogenic EBV than Ulcerative colitis or irritable bowel syndrome (90 % vs 66 % vs 0 % respectively). EBV increases the risk of lymphoma due to protein expression in transformed infected lymphocytes that results in immune evasion and suppression of apoptosis. Earlier studies have shown no evidence of higher risk of lymphoma in MC, however recently Bergman et al. (2021) analyzed data from Sweden´s pathology departments and from the Swedish Cancer Register and included 11758 patients with incident MC and found an increased risk of lymphoma (adjusted HR 1.43 [1.06–1.92]). Studies are needed to explore risk of lymphoma in subgroup of MC patients with EBV infection as inflammation cause by MC and concomitant EBV infection enhance the overall malignant potential. In conclusion, MC may not be as benign entity as it was once thought to be as it is more likely to harbor oncogenic EBV virus. Even diminutive polyps in MC can potentially harbor lymphoma and should be removed and submitted for analysis rather than being discarded.Figure 1.: Colonoscopy image showing small polyp (left) and schematic (right) of triangle between CMV, microscopic colitis and lymphoma error.

A clonality assay in canine B cell tumors targeting the immunoglobulin light chain lambda locus

Clonality assays for antigen receptor rearrangement have been used as adjunct examinations of lymphoproliferative diseases. These assays have been useful for differentiation between inflammation and clonal expansion of lymphocytes. Whereas the immunoglobulin heavy chain (IGH) and immunoglobulin light chain kappa (IGK) loci have been targeted in canine clonality assays previously, the immunoglobulin light chain lambda gene (IGL) locus has not yet been investigated. This study aimed to evaluate the usefulness of clonality assays in dogs using IGL. Canine diffuse large B cell lymphomas (DLBCL), cutaneous plasmacytomas, and pathologically diagnosed lymph nodes without lymphoma, were used in this study. Genomic DNA was extracted from formalin-fixed paraffin embedded sections. Sequences of IGLV and IGLJ were obtained from the ImMunoGeneTics database. Several primers against IGLVs and IGLJs were designed in the regions showing homology, by alignment of the gene segments. Products of polymerase chain reaction were analyzed on a capillary electrophoresis. In total, 20 of 23 cases of DLBCL showed clonality (87.0 %), whereas 8 of 30 cutaneous plasmacytomas were clonal (26.7 %). One of 23 lymph nodes without lymphoma showed clonality, thus the specificity was 95.7 %. These data indicate that the IGL locus could be a target for canine clonality assays and that the sensitivity of IGL-based clonality assays in cutaneous plasmacytomas was lower than that in DLBCL.

Extra copy number of BCL2 is correlated with increased BCL-2 protein expression and poor survival in diffuse large B-cell lymphoma treated with chemoimmunotherapy

The clinical significance of extra copy (EC) genotypes of BCL2, MYC, and BCL6 have not been fully elucidated. We evaluated the EC and translocation statuses of BCL2, MYC, and BCL6 in 190 diffuse large B-cell lymphoma (DLBCL) cases using fluorescence in situ hybridization. EC genotype was sub-classified according to copy number-gained tumor cell ratio (EC1, >20% but ≤50%; EC2, >50%). Only the BCL2-EC groups, not MYC-EC or BCL6-EC groups, displayed significantly increased immunoreactivity of the corresponding protein. Moreover, the BCL2-EC2 group was significantly associated with poor overall survival (OS) and progression-free survival (PFS) in a 147 R-CHOP-treated patient subset, which was also statistically significant as per the multivariate survival analysis for PFS. No significant differences in the survival of MYC, BCL6, concurrent BCL2/MYC, BCL6/MYC, BCL2/BCL6, or triple EC groups were observed. BCL2-EC may contribute to increased BCL-2 protein expression and serve as a predictor of treatment outcomes in DLBCL.

Study on influencing factors of anthracycline-induced subclinical cardiotoxicity in DLBCL patients administered (R)-CHOP

BackgroundAnthracycline-induced cardiotoxicity is an irreversible cardiac cell injury. Therefore, it’s very important to identify influencing factors of anthracycline-induced subclinical cardiotoxicity (AISC). This study was designed to analyze the influencing factors of AISC in patients with diffuse large B-cell lymphoma (DLBCL) treated with the (R)-CHOP chemotherapy regimen.MethodsThis is an ongoing observational prospective clinical trial. All patients underwent conventional echocardiography and speckle tracking echocardiography at the time of enrollment and during treatment. Changes of global longitudinal peak systolic strain were assessed after 3 cycles of (R)-CHOP chemotherapy, and patients were divided into the AISC and No-AISC groups. Demographic data, clinical variables, and biochemical variables were measured. Regression models, receiver operating characteristic curve analysis, and difference values were used to explore the relationships between variables and AISC.ResultsAmong 70 patients who completed 3 cycles of (R)-CHOP chemotherapy, 26 developed AISC. In multiple logistic regression, HDL-C (P = 0.047), ApoA1 (P = 0.022), TG (P = 0.029) and e’ (P = 0.008) were associated with AISC. The combination of HDL-C and NT-proBNP had the highest area under curves (AUC) for the diagnosis of AISC than HDL-C and NT-proBNP alone (AUC = 0.752, 95%CI: 0.63–0.87, P = 0.001). Between the No-AISC and AISC groups, there was no significant difference in HDL-C, ApoA1, and e’ at baseline and after 3 cycles of chemotherapy, respectively. The dynamic changes of HDL-C, ApoA1, and e’ from baseline to the end of the 3rd cycle of chemotherapy showed statistically significant differences.ConclusionsHDL-C, ApoA1, TG, and e’ are independent predictive factors in DLBCL cases treated with the (R)-CHOP chemotherapy regimen. The combination of HDL-C and NT-proBNP may improve the predictive ability for AISC in patients with DLBCL administered 3 cycles of (R)-CHOP chemotherapy. Dynamic changes of HDL-C, ApoA1, and e’ may be meaningful for predicting AISC.Trial registrationOur study was registered in the Chinese Clinical Trial Registry (Approval ID. ChiCTR2100054721 http://www.chictr.org.cn/showproj.aspx?proj=145082).

Primary diffuse large B-cell lymphoma of orbit: A population-based analysis.

ObjectivePrimary orbital lymphoma (POL) accounts for an essential part of adult orbital malignancies. Nevertheless, it remains a relatively rare lymphoid malignancy, accounting for <1% of all non-Hodgkin's lymphoma (NHL) cases. Orbital diffuse large B-cell lymphoma (DLBCL) is one of the most prevalent subtypes of POL that confers the worst outcomes. The prognostic determinants of orbital DLBCL remain unknown. Therefore, a retrospective analysis was conducted by investigating the Surveillance, Epidemiology, and End Results (SEER) database for independent predictive factors for the prognosis of orbital DLBCL.Materials and methodsUsing the SEER program, we acquired patient data including demographics, clinical characteristics, and treatment strategies. Our cohort included cases of primary orbital DLBCL diagnosed from 2000 to 2017. We conducted Kaplan-Meier analyses to visualize the overall survival (OS) and cause-specific survival (CSS). The Cox proportional hazard regression models were applied to assess the effects of these prognostic factors on OS and CSS.ResultsThe present cohort included 332 patients with orbital DLBCL. Age was the most impacted variable by orbital DLBCL. Three independent prognostic variables of orbital DLBCL were identified on diagnosis: advanced age, no radiation treatment, and late-stage (Stage IV). Moreover, patients who underwent chemotherapy demonstrated a greater OS when compared with those who did not. In orbital DLBCL, being unmarried was also a poor prognostic factor.ConclusionThe current study is the largest population-based case series of orbital DLBCL. The age at the time of diagnosis, marital status, absence of chemotherapy or radiotherapy, and tumor stage were all found to be correlated with worse prognosis.

Abstract A12: Pervasive hypermutation of super-enhancer regions dysregulates oncogene expression in diffuse large B-cell lymphoma

Abstract Coding-genome sequencing efforts have identified several genes/pathways altered in Diffuse Large B-cell Lymphoma (DLBCL), including new potential therapeutic targets. However, the mutational contribution of the non-coding genome of DLBCL remains largely unexplored. To identify functionally relevant non-coding mutations targeting regulatory domains, we integrated enhancer (E)/super-enhancer (SE) identification, by ChIP-seq analysis of the hallmark H3K27 histone mark, with whole genome sequencing (WGS) and RNA-seq analysis in 29 DLBCL cell lines representative of the major DLBCL subtypes, along with germinal center (GC) B cells representing the normal counterpart of DLBCL. Following validation in 93 normal/tumor DLBCL biopsies, we found that active SEs are specifically hypermutated (≥3 somatic mutations/Kb) in 99% of DLBCLs, as compared to the same loci when not active as SE (in total, 159 hypermutated SEs, with at least 2/case). As evidence of oncogenic relevance, we have shown that the hypermutated SEs linked to the BCL6 and BCL2 proto-oncogenes prevent the binding and transcriptional downregulation by transcriptional repressors. Genetic correction of selected mutations using the CRISPR/Cas9 technology restored repressor DNA-binding, downregulated target gene expression, and led to the counter-selection of cells harboring corrected alleles, indicating oncogenic dependency from the SE mutations. A third recurrently hypermutated SE was the CXCR4-SE, affected in 19% of cases. CXCR4 encodes for a G-protein coupled chemokine receptor involved in cell migration within the GC, and is mutationally activated in 40% of Waldenström macrobulinemia (WM), a post-GC lymphoproliferative disease. We identified a mutational hotspot preventing the binding of the NR3C1 glucocorticoid receptor in 7.5% of DLBCL cases. Correction of the mutations in cell lines led to counter selection and reduced expression of CXCR4. Conversely, the introduction of a mutation disrupting NR3C1 binding in WT DLBCL cells increased CXCR4 expression. Together, these results are consistent with dependency of the mutant cells on the CXCR4-SE mutation, and confirm a direct link between SE mutations in this region and deregulated gene expression through escape from NR3C1-mediated suppression. In primary cases, mutations in the NR3C1 binding site of the CXCR4-SE were observed in the absence of NR3C1 coding mutations and correlated with increased CXCR4 transcript levels, as documented by RNA-seq. Together with the oncogenic role of CXCR4 in WM, these findings reveal this chemokine receptor as a potential oncogenic target in DLBCL. Collectively, these findings reveal a new layer of genetic alterations, which identifies novel mechanisms of dysregulation for known oncogenes, as well as new dysregulated genes and pathways, with implications for precision classification and therapeutic targeting of DLBCL. * Co-senior authors. Citation Format: Elodie Bal, Rahul Kumar, Mohammad Hadigol, Antony B. Holmes, Laura K. Hilton, Jui Wan Loh, Kostiantyn Dreval, Jasper Wong, Sofija Vlasevska, Clarissa Corinaldesi, Rajesh Kumar Soni Soni, Katia Basso, Ryan D. Morin, Hossein Khiabanian, Laura Pasqualucci, Riccardo Dalla-Favera. Pervasive hypermutation of super-enhancer regions dysregulates oncogene expression in diffuse large B-cell lymphoma [abstract]. In: Proceedings of the Third AACR International Meeting: Advances in Malignant Lymphoma: Maximizing the Basic-Translational Interface for Clinical Application; 2022 Jun 23-26; Boston, MA. Philadelphia (PA): AACR; Blood Cancer Discov 2022;3(5_Suppl):Abstract nr A12.

Diffuse Large B Cell Lymphoma Arising in Patients with Preexisting Hodgkin Lymphoma.

The metachronic onset of diffuse large B-cell lymphoma (DLBCL) after classic Hodgkin lymphoma (cHL) is a rare event affecting patients’ outcomes. However, although several studies have investigated the prognostic role of this event, little is known about a hypothetical common origin of the two different neoplastic cells. Aims: To investigate a possible relationship between DLBCL and cHL, in this retrospective study of 269 patients with newly diagnosed cHL treated at Bari University Hospital (Italy) between 2007 and 2020, we analyzed data from 4 patients (3 male and 1 female) with cHL who subsequently developed DLBCL. Methods: Gene expression profile analysis, assessed by NanoString Lymphoma Subtype Assay, was performed to identify the cell of origin in the DLBCL cases, in addition to Hans’s algorithm. Results: Using Hans’s algorithm, all DLBCL cases showed a germinal center-B-Cell subtype. The gene expression profile evaluated by the NanoString Lymphoma Subtype Assay revealed two cases of the GCB molecular subtype, while the others were unclassified. After first-line chemotherapy, 1 patient achieved complete remission, 3 were non-responders (2 died of lymphoma within 6 months, whereas the other achieved complete remission after autologous and allogeneic stem cell transplantation and is still alive). Conclusions: The origin of the second neoplastic cell in patients with DLBCL with a previous history of cHL remains controversial, although the different immunophenotypic characteristics suggest that it may mainly arise de novo in a subject with a possible individual predisposition to develop lymphoid neoplasms.

Epstein barr virus associated Hodgkin and non-Hodgkin lymphoma

Background: The Epstein-Barr virus (EBV) has been linked to a variety of B-cell lymphomas, including Burkitt lymphoma (BL), classical Hodgkin lymphoma (cHL), and diffuse large B-cell lymphoma (DLBCL), at rates ranging from 5 to 10% of DLBCL cases to &gt;95% in endemic BL. Methods: The Present study conducted in AL-Najaf Holy City; it is a cross sectional study. All patients were recruited from Middle Euphrates Cancer Research Unit Laboratory, from pre-existing samples. Tissues collected from the previously mentioned laboratory were fixed in 10% formalin and placed in a cassette before being embedded in paraffine. The tissues were examined and diagnosed as with Hodgkin disease. Eighty samples were subjected in the present study. All study group was diagnosed formerly as paraffin imbedding blocks. Molecular analysis also used to detection of EBV-LMP-1 Gene. Histopathological examination using hematoxylin and eosine stain (H&amp;E) then examining under light microscope to check for EBV-LMP-1 protein in twenty block samples of tissues with lymphoma. Results: The result of the current study revealed that EBV-LMP-1 marker found in 12.5% of cases that had been diagnosed by PCR and IHC.

HDAC inhibitor chidamide synergizes with venetoclax to inhibit the growth of diffuse large B-cell lymphoma via down-regulation of MYC, BCL2, and TP53 expression.

Diffuse large B-cell lymphoma (DLBCL) is an aggressive type of non-Hodgkin's lymphoma. A total of 10%‒15% of DLBCL cases are associated with myelocytomatosis viral oncogene homolog(MYC) and/or B-cell lymphoma-2 (BCL2) translocation or amplification. BCL2 inhibitors have potent anti-tumor effects in DLBCL; however, resistance can be acquired through up-regulation of alternative anti-apoptotic proteins. The histone deacetylase (HDAC) inhibitor chidamide can induce BIM expression, leading to apoptosis of lymphoma cells with good efficacy in refractory recurrent DLBCL. In this study, the synergistic mechanism of chidamide and venetoclax in DLBCL was determined through in vitro and in vivo models. We found that combination therapy significantly reduced the protein levels of MYC, TP53, and BCL2 in activated apoptotic-related pathways in DLBCL cells by increasing BIM levels and inducing cell apoptosis. Moreover, combination therapy regulated expression of multiple transcriptomes in DLBCL cells, involving apoptosis, cell cycle, phosphorylation, and other biological processes, and significantly inhibited tumor growth in DLBCL-bearing xenograft mice. Taken together, these findings verify the in vivo therapeutic potential of chidamide and venetoclax combination therapy in DLBCL, warranting pre-clinical trials for patients with DLBCL.

Effects of hsa-miR-28-5p on Adriamycin Sensitivity in Diffuse Large B-Cell Lymphoma.

Background Adriamycin (doxorubicin) is an important traditional drug that exhibits cytotoxicity in Diffuse Large B-cell Lymphoma (DLBCL). Doxorubicin affects the DLBCL cells at all stages of their cell cycle. Combined with our previous results, this study discovered that the overexpression of hsa-miR-28-5p inhibited the proliferation, promoted apoptosis, and triggered cell cycle arrest at the S-phase in DLBCL cells. However, the effect of (Homo sapiens, hsa)-microRNA (miR)-28-5p on doxorubicin sensitivity in DLBCL has not been investigated. This study aims to reveal the effects of hsa-miR-28-5p on doxorubicin sensitivity at the level of DLBCL cells. Methods To determine the optimal concentration of doxorubicin, different concentrations of doxorubicin were used to treat DLBCL cells. CCK-8 assay was used to detect the proliferation of DLBCL cells. The hsa-miR-28-5p-mimic NC and hsa-miR-28-5p mimic were transfected to doxorubicin-mediated DLBCL cells. Simultaneously, blank control groups were set up. The cells were cultured and transfected for 24 h. Next, each group was administered with different concentrations of doxorubicin and cultured again for 24 h to observe the effects of hsa-miR-28-5p on doxorubicin sensitivity at different times. The proliferation, early apoptosis, and late apoptosis in DLBCL cells were determined using soft agar colony-forming assay, mitochondrial membrane potential assay, and caspase-3 activity assay, respectively. The apoptosis and cell cycle were explored using Annexin V-PE/7-AAD and PI/RNase staining buffer, respectively. We speculated that PD-L1 might be involved in the effect of hsa-miR-28-5p on the sensitivity of adriamycin (doxorubicin) in the DLBCL cells. Hence, we performed immunohistochemistry (IHC) to determine PD-L1 expression within formalin-fixed paraffin-embedded (FFPE) samples from 52 DLBCL cases. Results The optimal concentration of doxorubicin targeting DLBCL cells was found to be 3.028 μmol/l. The effect of doxorubicin on DLBCL cells was time- and concentration-dependent. hsa-miR-28-5p mimic + doxorubicin remarkably decreased proliferation of DLBCL. DLBCL cell apoptosis rate was the highest in hsa-miR-28-5p mimic + doxorubicin group. Apart from that, hsa-miR-28-5p mimic plus doxorubicin had the best effect in promoting DLBCL cell apoptosis. After the intervention of hsa-miR-28-5p mimic + doxorubicin on DLBCL cells, the cell cycle was arrested in the S-phase and DNA synthesis was blocked. hsa-miR-28-5p mimic + doxorubicin could regulate the cycle of DLBCL cells. As a result, overexpression of hsa-miR-28-5p combined with doxorubicin is possibly involved in the development of DLBCL by affecting the proliferation, apoptosis, and cycle of DLBCL cells. PD-L1 showed an association with the prognosis of DLBCL patients. Combining with the literature, this suggested hsa-miR-28-5p may influence DLBCL occurrence and therapeutic effect by regulating the PD-L1 level. Conclusion The combination of hsa-miR-28-5p mimic and doxorubicin may be considered more effective in inhibiting growth, arresting the cell cycle, and promoting cell apoptosis of DLBCL cells compared to using doxorubicin alone. The effects of doxorubicin on DLBCL cells were found to be time- and concentration-dependent. The overexpression of hsa-miR-28-5p enhanced the effect of doxorubicin on DLBCL cells, which may be attributed to the regulation of PD-L1 levels.

Primary Diffuse Large B-Cell Lymphoma of Ovary: Report of Cases and Literature Review

Objective: Our study aimed to review the characters of primary diffuse large B-cell lymphoma (DLBCL) of ovary and provide recommendations of management for this rare disease. Methods: We presented 4 cases of primary ovarian DLBCL (PODLBCL) from Beijing Chaoyang Hospital between 2003 and 2021. Furthermore, we searched PubMed and Web of Science database for literature published between 1998 and 2021.A total of 16 articles included 24 cases with histopathologically confirmed PODLBCL and detailed evaluation and follow-up were reviewed. Results: The median age of patients with PODLBCL was 43y (5-73y). The main clinical symptoms were pelvic mass, abdominal pain, followed by irregular vaginal bleeding and urinary incontinence. 25% patients had bilateral ovarian tumors, and 61.1% of unilateral tumors were in the left ovary. Cancer antigen 125 (CA125) and serum lactate dehydrogenase (LDH) were usually elevated to varying degrees. Most cases were diagnosed by surgery and presented in early stage. Treatments included surgery, chemotherapy and monoclonal antibody therapy. There was no evidence of recurrence within a median follow-up time of 20 months (range 5-72 months) in 79.1% (19/21) of patients. Conclusions: PODLBCL had no significantly specific character to distinguish from ovarian epithelial malignant tumors. The prognosis of patients with PODLBCL was usually good. We proposed that chemotherapy combined with monoclonal antibody therapy may be the first-line treatment for PODLBCL, and surgical resection of the tumor may be avoided. The key problem is how to make an early preoperative diagnosis. Therefore, more case reports and institutional studies are needed to confirm these conclusions.

Immunohistochemical subtyping of diffuse large B-cell lymphoma into germinal center B-cell and activated B-cell subtype, along with correlation of the subtypes with extranodal involvement, serum lactate dehydrogenase, and positron emission tomography scan-based response assessment to chemotherapy

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma in Indian population and is divided into the prognostically important subtypes, germinal center B-cell (GCB) and activated B-cell-like (ABC), using immunohistochemistry-based algorithm. The present study aims to evaluate the influence of immunohistochemical derived DLBCL subtype, GCB or ABC on prognostically significant variables - extranodal involvement and serum lactate dehydrogenase (LDH) level at presentation, and response to chemotherapy assessed on pre- and posttreatment fluorodeoxyglucose-positron emission tomography study. This was a retro-prospective, 2-year observational study at a tertiary health-care center, New Delhi. The study population includes a total 236 cases of DLBCL. According to the Hans algorithm, DLBCL cases were allocated to the GCB and ABC subgroups. For comparison of mean values, independent t-test and analysis of variance were used. For this purpose, we used SPSS 20.0 software. P < 0.05 was considered as statistically significant. Ninety-eight patients (41.5%) had GCB immunophenotype and 138 patients (58.5%) were ABC. A significant difference was observed between mean baseline level of LDH between GCB and ABC subtypes (P < 0.05). The proportion of cases with extranodal involvement was comparatively higher in ABC subtype (P < 0.05). Association between response to chemotherapy with DLBCL immunophenotypes was found to be highly significant (P < 0.00). The response rates were much better in GCB subtype. The mean baseline level of LDH is significantly higher in ABC subtype. The proportion of cases with extranodal involvement was comparatively higher in ABC and shows poor response to chemotherapy as compared to GCB. Baseline LDH level was found to be important prognostic marker in the DLBCL.

PB2095: RELAPSED AND REFRACTORY DIFFUSE LARGE B CELL LYMPHOMA: EXPERIENCE OF A LOW-INCOME CENTER IN TIME OF NEW DRUGS

Background: Refractory/relapsed (RR) disease is the main cause of morbidity and mortality in Diffuse Large B cell Lymphoma (DLBCL). Unfortunately, one-third of patients with diffuse large B-cell lymphoma continue on to relapsed or refractory disease despite the improvement of its management. Aims: The aim of this study is to evaluate our management of RR disease in our low-income center in the era of immunotherapy and monoclonal antibodies. Methods: This is a single-center retrospective study. We included all the cases of DLBCL diagnosed in University Hospital of Sfax between 2008-2019 that were refractory and/or relapsed. Clinical and biological characteristics at diagnosis were reported. A second biopsy was indicated in all cases when feasible. Refractory disease was defined as the absence of criteria of remission (complete or partial). Relapse was defined as the appearance of new lesions or the increase of at least 50% from nadir in the SPD from any previously involved site after a complete remission. Early relapse was defined as a relapse happening 12 months after end of treatment. The patients were treated with a second-line platinum based chemotherapy if fit. Autologous stem cell transplantation (ASCT) was indicated for patients who respond to second line treatment (partial or complete remission) and are fit for ASCT. Kaplan Meier system was used to estimate survival. Results: Among the 150 DLBCL diagnosed and treated during the study, 46 (31%) were relapsed/refractory: 13 (9%) were refractory to first line chemotherapy and 33 experienced relapse (22%). At the diagnosis, RR-patients are aged of 60 and less in 69% of the cases. A poor performans status≥2 was found in 30% of the cases. We found raised LDH levels in 53%. The disease was localized in 31%. aaIPI was at a minimum of 1 in 87% of the cases (1: 42%, 2: 24%, 3: 21%). We identified 3 predictive factors of refractory disease: Performans status (p=0,007), aaIPI (p=0,036) and raised LDH (p=0,019). For patients who relapsed, an early relapse was noted in 51,5% of the cases. Five patients relapsed after ASCT. Mean time from diagnosis was 20 months (2-72). Twenty-six patients were eligible for chemotherapy: 20 were treated with DHAP and 6 with ICE regimen. Five patients were in complete remission after salvage chemotherapy and 3 were in partial remission. Only 1 patient underwent ASCT after relapse and 3 patients after refractory disease. 1-year and 5-years Post-RR survival were respectively 24% and 14%. Summary/Conclusion: Even in the Rituximab era, patients continue to experience relapse and refractory disease. Our results are comparable to the literature where one third of DLBCL are either refractory (10-15%) or relapse (20-30%) and most relapses happen within the first 2 years after treatment. Predictive factors of RR identified in our study are the same than the factors reported in the literature in addition to age, B symptoms, advanced stage of the disease and bulk. Post-RR survival was poor in our study as well as in reports from the literature. The poor survival post-RR could be improved with new drugs regrettably not available in our country.

P1168: CHARACTERISTICS PREDICTIVE OF PROGRESSION DURING FRONTLINE TREATMENT IN AGGRESSIVE B-CELL LYMPHOMAS

Background: Primary refractory diffuse large B-cell lymphoma (DLBCL) represents 10-15% of DLBCL cases. The subgroup of refractory patients who have no response or progressive disease (PD) by the end of frontline treatment (EOT) is a high-risk group with particularly poor outcomes. It is challenging to identify such patients at diagnosis. Aims: To identify clinical, pathological, and cytogenetic characteristics of patients with progression during frontline treatment. Methods: Adult patients with newly diagnosed DLBCL, including patients with high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements (DHL/THL), between 2002 and 2019 and seen at Mayo Clinic Rochester were identified from the prospective Molecular Epidemiology Resource (MER) cohort study of the University of Iowa/Mayo Clinic Lymphoma SPORE. We analyzed patients who had no response or PD during treatment or by EOT (early PD group) and compared to non-early PD (non-ePD) patients (including relapsed patients). We compared demographics, clinical characteristics, cell of origin (COO), and MYC rearrangements using Chi-square analysis. Results: Out of 1,505 patients with DLBCL, there were 66 patients (4.3%) with early PD (N=20 PD/stable disease at interim PET-CT, N=46 PD by EOT). At baseline, 61% were male and the median age was 60. Early PD patients had more advanced stage III-IV (72.7% vs 53.3%), elevated serum lactate dehydrogenase (LDH) (64.0% vs 47.3%), >1 extranodal site involved (36.4% vs 23.3%), and International Prognostic Index (IPI) ≥3 (52.0% vs 33.6%)(all p <0.05 compared to non-ePD). COO distribution was similar between early PD and non-ePD patients. Among patients with complete pathological and cytogenetic data available (early PD, n=47; non-ePD, n=813), DHL or THL was observed in 23.4% of early PD patients compared to 9.2% in non-ePD patients (p=0.001). Of the DHL patients in the early PD group (n=8), MYC/BCL2 rearrangement was present in 87.5%, MYC/BCL6 in 12.5%. Dual Myc/Bcl2 expressor (DEL) was present in 42.2% of early PD patients (n=45) compared to 25.5% in non-ePD patients (n=736)(p=0.013). First-line treatment regimens in the early PD group included R-CHOP (74.2%), R-EPOCH (7.6%), and other immunochemotherapy (IC)(18.2%), which was similar to non-ePD patients. Summary/Conclusion: High-risk characteristics including DHL/THL and DEL are significantly associated with progressive disease during frontline treatment, suggesting that MYC-signaling may mediate chemoresistance. Known high-risk clinical features including advanced stage, elevated LDH, >1 extranodal site, and IPI ≥3 are also associated with early PD. Early identification of patients at high risk for early PD through clinical, pathological, and cytogenetic features is of utmost importance given the availability of clinical trials incorporating novel therapies in both frontline and consolidative approaches.