Unique endoscopic features of primary biliary diffuse large B-cell lymphoma: A case report with literature review (with video).

A 67-year-old man visited our hospital complaining of dark-colored urine and upper abdominal pain. Magnetic resonance cholangiopancreatography showed stricture of the distal bile duct, and contrast-enhanced computed tomography showed irregular thickening of the distal bile duct wall. However, no enlarged lymph nodes, pancreatic tumors, or other neoplastic lesions were apparent around the bile duct. Endoscopic ultrasonography and intraductal ultrasonography showed irregular thickening of the inner hypoechoic layer without the disappearance of the innermost thin hyperechoic layer. On the basis of these findings, we considered that the bile duct lesion was of non-epithelial origin. Thus, we repeatedly performed bile duct biopsies from the same site under fluoroscopy to obtain a sample of the submucosal tissue. The pathological diagnosis was diffuse large B-cell lymphoma, and the patient received systemic chemotherapy (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone). After six courses of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone, positron emission tomography-computed tomography showed the disappearance of 18-fluorodeoxyglucose uptake in the bile duct and endoscopic retrograde cholangiography showed improvement of the bile duct stricture. Endoscopic findings and repeated biopsies were useful in making the diagnosis of primary biliary diffuse large B-cell lymphoma.

Extra-Limbic Seronegative Encephalitis Preceding Recurrent Hodgkin's Lymphoma and Gastric Diffuse Large B-Cell Lymphoma: A Case Report.

We describe a patient with extra-limbic seronegative encephalitis with relapsing progressive course as the harbinger of sequential Hodgkin's lymphoma and Diffuse Large B-Cell lymphoma. Diagnosis of probable paraneoplastic neurologic syndrome (PNS) was arrived at by exhaustive elimination of alternative causes and supportive tissue diagnosis. This case highlights the phenotypic variety of paraneoplastic neurologic syndromes associated with hematologic malignancies and the challenges in their recognition, diagnosis, and treatment. We discuss and apply the updated consensus diagnostic criteria for paraneoplastic syndromes to our case as a means of bolstering probability in cases of diagnostic uncertainty.

Clinician's perspective on the diagnosis of primary cutaneous B-cell lymphoma.

Of all cutaneous lymphomas, 25% are primary cutaneous B-cell lymphomas (PCBCLs). Of these, primary cutaneous follicle center lymphoma (PCFCL), primary cutaneous marginal zone B-cell lymphoma (PCMZL), and primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT) are the most common subtypes. For the diagnosis of PCBCLs, a biopsy combined with immunohistochemistry and histological examination is the gold standard. PCBCLs are categorized into indolent or intermediate to aggressive subtypes based on their clinical behavior in a clinically oriented approach. PCDLBCL-LT has an aggressive course that spreads to extracutaneous sites in about 45% of cases, whereas PCFCL and PCMZL are indolent diseases. As a result, instrumental staging is advised for PCDLBCL-LT but not for extracutaneous disease after a diagnosis of PCMZL or PCFCL. Lastly, dermatoscopy may offer a novel diagnostic tool to improve the clinical recognition of various PCBCL subtypes when used in conjunction with a strong clinical suspicion.

Circulating tumor DNA in diffuse large B-cell lymphoma: analysis of response assessment, correlation with PET/CT and clone evolution.

INTRODUCTION: Circulating tumor DNA (ctDNA) can be obtained from cell-free DNA (cfDNA) andis a new technique for genotyping, response assessment and prognosis in lymphoma. METHODS: Eighteen patients with samples at diagnosis (ctDNA1), after treatment (ctDNA2) and extracted from diagnostic tissue (FFPE) were evaluated. RESULTS: In all patients, at least one mutation in cfDNA was detected at diagnosis. CREBBP was the most frequent mutated gene (67 %). In 12 of the 15 patients with complete remission, the mutation attributed to the disease found at diagnosis cleared with treatment. A reduction in the ctDNA was observed after treatment in 14 patients, 12 of whom achieved complete remission. Correlations were found between the ctDNA at diagnosis and total metabolic tumor volume (r = 0.51; p-value = 0.014) and total lesion glycolysis 2.5 (r = 0.47; p-value = 0.024) by PET at diagnosis and between ctDNA at diagnosis and radiomic features of the lesions with the largest standardized uptake value. There was a strong inverse correlation between ΔctDNA1 and ΔSUVmax by PET/CT (r = -0.8788; p-value = 0.002). CONCLUSION: Analysis of ctDNA and PET/CT in large B-cell lymphoma are complementary data for evaluating tumor burden and tumor clearance after treatment. Analysis of radiomic data might help to identify tumor characteristics and their changes after treatment.

A novel EZH1/2 dual inhibitor inhibits GCB DLBCL through Cell Cycle Regulation and M2 Tumor-Associated Macrophage Polarization.

The incidence of germinal center B-cell-like type diffuse large B-cell lymphoma (GCB DLBCL) is steadily increasing, with a known hereditary component. Although some molecular mechanisms in GCB DLBCL have been elucidated, understanding remains incomplete, limiting the effectiveness of targeted therapies. In GCB DLBCL patients, abnormally high expression of zeste homologs 2 (EZH2) is noted, and the compensatory effect of EZH1 following EZH2 inhibition contributes to poor prognosis. This highlights the potential of dual targeting of EZH1/2 as a promising strategy. In this study, we developed a novel inhibitor, EZH-1-P2, targeting EZH1/2, and evaluated its anti-tumor effects on DLBCL cells. Mechanistically, inhibition of EZH1/2 affects the epigenetic regulation of gene expression related to p53, impacting cell cycle progression and GCB DLBCL cell growth. Additionally, while EZH1/2 inhibition impacts NOTCH signaling, the precise mechanism by which it affects M2-type tumor-associated macrophage (M2-TAM) polarization and germinal center expansion requires further investigation. Our research introduces EZH-1-P2 as a novel inhibitor with potential as a candidate for GCB DLBCL therapy, although further studies are needed to fully elucidate its mechanisms.

EQ-5D-5L and SF-6Dv2 health utilities scores of diffuse large B-cell lymphoma patients in China.

BACKGROUND: This study evaluates the health-related quality of life (HRQoL) of persons with diffuse large B-cell lymphoma (DLBCL) by using EQ-5D-5L and SF-6Dv2 and compares the measurement properties of the two instruments. METHOD: DLBCL patients were identified via a patient group and were surveyed using web-based questionnaires. Demographic information, socioeconomic status (SES), clinical characteristics, and EQ-5D-5L and SF-6Dv2 responses were collected and statistically described. The association between the EQ-5D-5L and SF-6Dv2 dimensions were analyzed using the Spearman's correlation coefficient, whereas the correlation of the utility scores was evaluated using Pearson's correlation coefficient. The agreement between the responses of the two instruments were examined using a Bland-Altman (B-A) plot. A one-way analysis of variance (ANOVA) was performed to compare the utility scores across subgroups in different clinical states (a t-test was used if there were two subgroups). In addition, the graded response model (GRM) was used to describe the discrimination ability and difficulty characteristics of the dimensions in the two instruments. RESULTS: In total, 582 valid responses were collected, among which 477 respondents were associated with initial-treatment and 105 respondents were relapsed/refractory (RR) patients. The mean (standard deviation [SD]) EQ-5D-5L and SF-6Dv2 utility scores of the DLBCL patients were 0.828 (0.222) and 0.641 (0.220), respectively. The correlation between the EQ-5D-5L and SF-6Dv2 dimensions ranged from 0.299 to 0.680, and the correlation between their utility scores was 0.787. The B-A plot demonstrated an acceptable but not strong agreement between EQ-5D-5L and SF-6Dv2 utility scores. The GRM model results indicated that all dimensions of each instrument were highly discriminating overall, but EQ-5D-5L had suboptimal discriminative power among patients with good health. CONCLUSION: Both the EQ-5D-5L and SF-6Dv2 showed valid properties to assess the HRQoL of DLBCL patients. However, utility scores derived from the two instruments had substantial difference, thereby prohibiting the interchangeable use of utilities from the two instruments.

Comparison of Thiotepa-based Conditioning Regimens for Older Adults with Primary Diffuse Large B-cell Lymphoma of the Central Nervous System Undergoing Autologous Hematopoietic Cell Transplantation.

BACKGROUND: In this study, we compare outcomes of older patients with primary diffuse large B-cell lymphoma of the central nervous system (PCNSL) undergoing autologous hematopoietic cell transplantation (autoHCT) with either thiotepa/carmustine (BCNU/Thio) or thiotepa/busulfan/cyclophosphamide (TBC) conditioning. METHODS: We used a post-publication dataset made available by the Center for International Blood and Marrow Research (CIBMTR) including patients who were ≥65 years in age with PCNSL and underwent autoHCT as consolidation with TBC or BCNU/Thio conditioning. RESULTS: Out of 147 patients; n=84 received BCNU/Thio and n=63 received TBC. The 1-year NRM in the BCNU/Thio group was 10% versus 22% in the TBC group (p=0.05) and the 2-year relapse rate was 5% versus 5%, respectively (p=1.00). The 2-year PFS in the BCNU/Thio group was 85% versus 71% in the TBC group (p=0.05) and 2-year OS was 86% vs 74% (p=0.08). In a multivariable regression model, BCNU/Thio was associated with a lower risk for NRM [Hazard Ratio (HR), 0.33, p=0.009], improved PFS (HR, 0.41, p=0.008) and OS (HR, 0.37, p=0.007), but there was no association with relapse risk. CONCLUSION: We found that in older adults with PCNSL undergoing consolidation with autoHCT, BCNU/Thio conditioning is associated with lower NRM and improved OS compared to TBC.

The future of immunotherapy for diffuse large B-cell lymphoma.

With the introduction of anti-CD19 chimeric antigen receptor (CAR) T-cell (CAR T) therapies, bispecific CD3/CD20 antibodies and anti-CD19 antibodies, immunotherapy continues to transform the treatment of diffuse large B-cell lymphoma (DLBCL). A number of novel immunotherapeutic strategies are under investigation to build upon current clinical benefit and offer further options to those patients who cannot tolerate conventional intensive therapies due to their age and/or state of health. Alongside immunotherapies that leverage the adaptive immune response, natural killer (NK) cell and myeloid cell-engaging therapies can utilize the innate immune system. Monoclonal antibodies engineered for greater recognition by the patient's immune system can enhance antitumor cytotoxic mechanisms mediated by NK cells and macrophages. In addition, CAR technology is extending into NK cells and macrophages and investigational immune checkpoint inhibitors targeting macrophage/myeloid cell checkpoints via the CD47/SIRPα axis are in development. Regimens that engage both innate and adaptive immune responses may help to overcome resistance to current immunotherapies. Furthermore, combinations of immunotherapy and oncogenic pathway inhibitors to reprogram the immunosuppressive tumor microenvironment of DLBCL may also potentiate antitumor responses. As immunotherapy treatment options continue to expand, both in the first-line setting and further lines of therapy, understanding how to harness these immunotherapies and the potential for combination approaches will be important for the development of future DLBCL treatment approaches.

The gut microbiota is altered significantly in primary diffuse large b-cell lymphoma patients and relapse refractory diffuse large b-cell lymphoma patients.

PURPOSE: Studies have shown that the gut microbiota may affect anti-tumor immunity by regulating the host immune system and tumor microenvironment. To date, little is known about whether the gut microbiota underlies the occurrence of diffuse large B-cell lymphoma (DLBCL) and drug resistance. METHODS: In the present study, we compared the gut microbiota structure of fecal samples from 26 patients with primary DLBCL, 28 patients with relapsed and refractory (RR) DLBCL, and 30 healthy people. RESULTS: Notably, Fusobacteria (from phylum to species) was enriched in the primary group. A decrease of Fusobacterium and an increase of Enterococcus were found in the RR group. PICRUSt analysis found that genes related to cytochrome P450 were upregulated in the RR group compared to the primary group, which likely contributes to the occurrence of DLBCL and the formation of drug resistance. CONCLUSIONS: Our study provides further evidence for the relationship between gut microbiota and DLBCL and the formation of drug resistance, highlighting the potential significance of the bacterial variations may be used as new biomarkers of DLBCL.

Gene regulatory mechanisms of T cell exhaustion in diffuse large B cell lymphoma based on single-cell transcriptome data.

Diffuse large B cell lymphoma (DLBCL) is a heterogeneous and aggressive B cell malignancy that accounts for about 30 % of non-Hodgkin lymphomas. The current standard treatment for DLBCL is rituximab plus chemotherapy, but many patients are refractory or relapse, indicating the need for improved understanding of its molecular pathology. T cell exhaustion is a state of dysfunction or impairment that occurs in chronic infections or cancers, and is associated with poor prognosis in DLBCL. However, the molecular mechanisms of T cell exhaustion in DLBCL are poorly understood. In this study, we performed a comprehensive analysis of T cell exhaustion in DLBCL using public single-cell transcriptome data. We identified different subtypes of T cells and characterized their gene expression features. We found that DLBCL had a significantly higher proportion of exhausted T cells than normal tonsil, and that exhausted T cells had distinct gene expression signatures from non-exhausted T cells. These signatures included genes related to inhibitory receptors, cytokines, transcription factors and metabolic enzymes. We also found that ID3 gene was significantly upregulated in exhausted T cells in DLBCL, which may play a key role in T cell exhaustion. We constructed a protein-protein interaction network, identifying major hub proteins involved in T cell exhaustion or migration. We also performed KEGG and GO enrichment analysis for the differentially expressed genes between exhausted and non-exhausted T cells, and found important signaling pathways related to T cell exhaustion in DLBCL. Our results provide new insights into the molecular mechanisms underlying T cell exhaustion and offer novel therapeutic targets for this complex disease.

Imatinib mesylate reduces c-MYC expression in double-hit lymphoma cells by suppressing inducible cytidine deaminase.

BACKGROUND: Double-hit lymphoma (DHL) with c-MYC gene translocation is highly aggressive and has a poor prognosis. In DHL cells, activation-induced cytidine deaminase (AID) promotes antibody class switch recombination (CSR), ultimately leading to c-MYC gene translocation caused by Myc/IgH DNA double-strand breaks. However, currently there is still no method to suppress the expression of AID. METHODS: In this study, we compared the clinical significance of AID expression in DHL, Additionally, two human double-hit lymphoma cell lines were used to analyze the effect of imatinib mesylate on c-MYC in vitro, and the therapeutic effect was also evaluated in xenograft mouse models. RESULTS: Imatinib mesylate downregulated the AID and c-MYC proteins in patients with chronic myelogenous leukemia associated with DHL. In addition, imatinib mesylate reduced AID and c-MYC expression in SU-DHL-4 and OCI-Ly18 DHL cells. Imatinib mesylate exerted significant inhibitory effects on the proliferation and metastasis of SU-DHL-4 and OCI-Ly18 cells. Finally, imatinib mesylate reduced not only tumor burden in DHL mouse models, but also AID and c-MYC expression in vivo. CONCLUSION: These findings reveal that imatinib mesylate effectively reduces the carcinogenic function of c-MYC in DHL, providing novel strategies for developing therapies targeting c-MYC-driven DHL.

Neurolymphomatosis mimicking a Guillain-Barré syndrome triggered by COVID-19 vaccination.

Guillain-Barré syndrome (GBS) is an acute disorder of the peripheral nervous system, causing flaccid paralysis, areflexia, and variable sensory involvement. Proximal as well distal muscles of the limbs can be involved, and in most severe and advanced cases progresses to respiratory failure and death. GBS is considered an autoimmune disease, and at the basis of the attack at the peripheral nervous system different mechanisms have been recognized, in particular viral infections or other immune stimulations. Cranial nerve involvement in patients with diffuse large B-cell lymphoma (DLBCL) and primary central nervous system lymphoma are rare conditions that could present with similar clinical features. Here we present a case of a 36-year-old man hospitalized for acute polyradiculoneuritis of the cranial nerves and lumbar roots that arose a 14 days after severe acute respiratory syndrome COVID-19 2 (Sars-CoV-2) vaccination. Most of the main criteria for the diagnosis of GBS were met, including clinical and electrophysiological criteria. Albuminocytologic dissociation and high protein level in cerebrospinal fluid were also found. Therefore, the patient was treated with a cycle of intravenous immunoglobulin (IVIG) with notable improvement of symptoms and gradual recovery of motility. A five months later, following SARS-CoV-2 infection, the patient presented with worsening of neurological symptoms and was readmitted to the hospital. He underwent instrumental tests again and was treated with repeated cycles of IVIG and then with a cycle of plasmapheresis without any improvement. In the following 10 days he developed very serious conditions; he was transferred to intensive care unit and deceased after 6 days. The cause of the neurological syndrome was determined only after autoptic analysis, which revealed the presence of primary peripheral nervous system (PNS) DLBCL. The reported case highlights that GBS-like presentation always requires a careful differential diagnosis, and physicians should also consider the possibility of an occult cancer.

Identification of Immune-Related Gene Pair Signature to Predict Prognosis of Diffuse Large B-Cell Lymphoma Based on Bioinformatics Analyses.

Since over one-third of DLBCL patients experience relapse or refractory after standard therapy, high-risk patients must be predicted. We developed a prognostic immune-related gene pairs (IRGPs) signature for DLBCL patients using bioinformatics analyses. This signature can predict the prognosis of these patients adequately, either alone or in combination with other clinical parameters. It hopes to improve the stratification and management of these patients for broad clinical applications.

Primary Breast Lymphoma: A Case Report of a Common Tumor in an Uncommon Location.

Primary breast lymphoma (PBL) is a rare malignant lymphoid neoplasm limited to the breast, accounting for about 0.15% of all malignant breast tumors and 1.7% to 2.2% of extra-nodal lymphomas. PBL must be distinguished from conventional breast carcinomas due to different therapeutic approaches. A 25-year-old female presented with a left breast mass. Histopathology and immunohistochemical tests confirmed the diagnosis of diffuse large B-cell lymphoma (DLBCL). She had no similar lesions elsewhere in the body. She received 1 cycle of R-CHOP chemotherapy but absconded from the treatment and succumbed afterward while at home. Recent developments in DLBCL treatment have greatly improved patient outcomes by incorporating targeted medicines like rituximab, increased chemotherapy regimens, new drugs, and individualized treatment techniques. PBL appears to have a worse prognosis; thus, delay or abscondment from treatment is of serious concern when it comes to improving the prognosis of patients with PBL.

A Real-World Data-Based Analysis of Prognostic Indices as Part of Trial Eligibility Criteria in Diffuse Large B-Cell Lymphoma Patients.

OBJECTIVES: Recent front-line clinical trials used the International Prognostic Index (IPI) to identify trial-eligible patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). However, many IPI-like variants with improved accuracy have been developed over the years for rituximab-treated patients. METHODS: We assessed the impact of International Prognostic Indices on patient enrolment in clinical trials, aiming to exclude low-risk IPI patients based on POLARIX/EPCORE DLBCL-2 trial criteria. RESULTS: We identified 2877 patients in the Danish Lymphoma Registry who would have been eligible for the POLARIX trial if patients with IPI 0-1 scores were included. IPI and NCCN-IPI assigned 33.3% and 11.9% of patients to the low-risk group, respectively. Shorter 5-year overall survival (91.4% vs. 97.5%), higher relapse rate (9.9% vs. 4.4%), and more deaths (16.1% vs. 4.4%) occurred in the low-risk IPI group compared with low-risk NCCN-IPI group. Analyzed models failed to identify true high-risk patients with poor prognosis. Similar results were found in the confirmatory cohort developed based on EPCORE DLBCL-2 trial eligibility criteria. CONCLUSION: True low-risk patients are more optimal identified by NCCN-IPI and should be excluded from front-line clinical trials due to their excellent prognosis. However, additional high-risk factors besides clinical prognostic models need to be considered when selecting trial-eligible patients.

Tumour-associated macrophages in diffuse large B-cell lymphoma: the prognostic and therapeutic impact in a South African centre with high HIV seroprevalence.

Diffuse large B-cell lymphoma (DLBCL) is a common malignancy among people living with HIV. Macrophage enrichment of the tumour microenvironment (TME) is a prognostic factor in DLBCL among immunocompetent people, with some studies reporting that macrophage enrichment predicts a superior response to rituximab therapy. The macrophage phenotype is also important, with reportedly poorer outcomes with enrichment of anti-inflammatory (M2) macrophages. To date, the relationship between the type/number of tumour macrophages and outcomes in HIV-associated DLBCL (HIV-DLBCL) has been poorly explored. In this study, we assessed tumour macrophage numbers in a South African cohort of patients with DLBCL and a high HIV-seropositivity rate. Immunohistochemistry for CD68 and CD163 was performed on the diagnostic biopsies of 79 patients with DLBCL. Relevant information was documented from the clinical records, including disease stage, international-prognostic index score, HIV-related parameters, C-reactive protein, ferritin levels and immune cell numbers (monocytes, lymphocytes and neutrophils). Survival analysis was performed using Kaplan-Meier survival estimates, and the correlation between tumour macrophage numbers and a variety of immunological parameters was assessed using Spearman's rho. Of the 79 patients included, 87.2% were living with HIV, and rituximab therapy was used in 46.9%. Tumour macrophage numbers were not related to HIV status, but low pro-inflammatory (M1) macrophage numbers (CD68 + CD163 -) were significantly associated with poorer outcomes (HR 2.02, p = 0.03). M2 macrophage (CD68 + CD163 +) enrichment was not predictive of survival but was associated with improved response to rituximab therapy (HR 0.19; p = 0.002). Macrophage numbers were marginally correlated with ferritin levels, which showed modest performance as a peripheral blood biomarker of the TME macrophage status (AUC 0.6 at a level of 374 µg/L), and high ferritin levels were associated with a superior response to rituximab-therapy (HR 0.28, p = 0.034). Pro-inflammatory macrophages are important in tumour control in HIV-DLBCL, while M2 macrophage enrichment improves the response to rituximab therapy. Ferritin shows promise as a biomarker for identifying patients more likely to benefit from rituximab therapy.

Diffuse large B-cell lymphoma of the gallbladder with hepatoduodenal invasion exhibiting a necrotic tendency.

We report a case of diffuse large B-cell lymphoma (DLBCL) of the gallbladder with extensive hepatoduodenal invasion, which was challenging to diagnose histologically due to a strong tendency to be necrotic. An 71 year-old man presented with upper abdominal pain and was referred to our hospital. Computed tomography revealed a distended gallbladder with air within the irregular gallbladder wall and an indistinct border with the hepatoduodenum, suggesting invasion. Esophagogastroduodenoscopy detected an ulceration in the duodenal bulb. However, histologic analysis failed to provide a definitive diagnosis due to the presence of necrotic tissue. Furthermore, direct biopsy from the gallbladder mucosa by endoscopic retrograde cholangiography revealed only necrotic tissue and no diagnosis. Contrast ultrasonography for the hepatic invasion revealed enhancement with blood flow, suggesting non-necrotic tissue. Subsequently, an ultrasound-guided core-needle biopsy was conducted to obtain tissue samples from the described lesion. The pathology showed atypical lymphocytes with irregular nuclei. Immunostaining indicated positive expression of CD10, CD20, Bcl-6, and C-Myc, consistent with a diagnosis of DLBCL. In our case, the lymphoma exhibited a strong tendency to be necrotic, making histologic diagnosis difficult. However, selective biopsy from the site of blood flow made the diagnosis possible and proved to be useful.

Multimodality Radiologic and Pathologic Findings in Large B-cell Lymphoma With Hepatic Presentation in an Unusually Young Male.

Diffuse large B-cell lymphoma (DLBCL) is the most prevalent type of non-Hodgkin lymphoma (NHL), and typically presents in patients who are at least 60 years old with gastrointestinal (GI) tract involvement. We report a case of a young patient with DLBCL. A 27-year-old African American male presented to the emergency room with complaints of abdominal distention. Imaging showed hepatosplenomegaly with multiple nodular lesions in both the liver and spleen. The biopsy confirmed a diagnosis of DLBCL. This case report highlights a rare clinical presentation of DLBCL due to the uncommon hepatic initial presentation of the disease paired with the patient's age and race varying significantly from the demographic norm. Clinicians should maintain a high index of suspicion for DLBCL in patients with atypical extranodal involvement, such as in this patient, to optimize patient outcomes.

Association of overall survival benefit of radiotherapy with progression-free survival after chemotherapy for diffuse large B-cell lymphoma: A systematic review and meta-analysis.

Objective: To evaluate whether improved progression-free survival (PFS) from radiotherapy (RT) translates into an overall survival (OS) benefit for diffuse large B-cell lymphoma (DLBCL). Methods: A systematic literature search identified randomized controlled trials (RCTs) and retrospective studies that compared combined-modality therapy (CMT) with chemotherapy (CT) alone. Weighted regression analyses were used to estimate the correlation between OS and PFS benefits. Cohen's kappa statistic assessed the consistency between DLBCL risk-models and PFS patterns. Furthermore, the benefit trend of RT was analyzed by fitting a linear regression model to the pooled hazard ratio (HR) according to the PFS patterns. Results: For both 7 RCTs and 52 retrospective studies, correlations were found between PFS HR (HRPFS) and OS HR (HROS) at trial level (r = 0.639-0.876), and between PFS and OS rates at treatment-arm level, regardless of CT regimens (r = 0.882-0.964). Incorporating RT into CT increased about 18% of PFS, and revealed a different OS benefit profile. Patients were stratified into four CT-generated PFS patterns (>80%, >60-80%, >40-60%, and ≤40%), which was consistent with risk-stratified subgroups (kappa > 0.6). Absolute gain in OS from RT ranged from ≤5% at PFS >80% to about 21% at PFS ≤40%, with pooled HROS from 0.70 (95% CI, 0.51-0.97) to 0.48 (95% CI, 0.36-0.63) after rituximab-based CT. The OS benefit of RT was predominant in intermediate- and high-risk patients with PFS ≤ 80%. Conclusion: We demonstrated a varied OS benefit profile of RT to inform treatment decisions and clinical trial design.