Tonsillar Diffuse Large B-Cell Lymphoma of Non-Germinal Center Type With Cluster of Differentiation 5 Positive in a Pediatric Girl.

Lymphoma is a common malignancy in children. It is the second most common malignancy in children older than 1 year of age. Most extranodal non-Hodgkin lymphoma (NHL) in the head and neck is usually caused by diffuse large B-cell lymphoma (DLBCL), but pediatric DLBCL with cluster of differentiation (CD)5 expression is rarely discussed in the literature. An 8-year-old Saudi female presented with painful swallowing for a year. She underwent tonsillectomy. Histopathology and immunohistochemistry studies show stage II NHL as DLBCL in the left tonsil, non-germinal center B-cell (non-GCB) with aberrant CD5 expression. She completed all cycles of chemotherapy. She experienced febrile neutropenia after the first cycle but did not have any other complications. Current chemotherapy has an excellent prognosis, but the treatment approach depends on the disease stage risk classification. We emphasized that malignancy is not excluded by the absence of constitutional symptoms.

Prognostic Significance of Bcl-2 Expression in Non-germinal Center B-cell-Like Diffuse Large B-cell Lymphoma.

INTRODUCTION: Diffuse large B-cell lymphomas (DLBCLs) are a group of malignant neoplasms with extensive clinical and molecular heterogeneity. Several key genetic aberrations have been identified, such as those involving the MYC, BCL6, and BCL2 genes. Prior studies on the prognostic significance of Bcl-2 protein expression in DLBCL have been contradictory, with some suggesting it has an adverse effect, while others have shown no such association. Bcl-2 is known to be more highly expressed in the non-germinal center B-cell-like (non-GCB) subtype compared to germinal center B-cell-like (GCB) DLBCL. Non-GCB status is associated with a less favorable prognosis. This study aimed to investigate whether the expression of Bcl-2 protein in non-GCB DLBCL influences response to treatment, progression-free survival, or overall survival. METHODS: In this retrospective study, we investigated whether there was a difference in the clinical outcomes of non-GCB DLBCL cases (n = 97) that were confirmed by immunochemistry to demonstrate high levels of Bcl-2 protein expression (>50% neoplastic cells stained) when compared to those who were deemed negative based on this criterion. Response to rituximab-based induction immunochemotherapy, five-year progression-free survival, and five-year overall survival were assessed. RESULTS: There was no statistically significant difference in response to treatment, five-year progression-free survival, or five-year overall survival between the patients who were positive for Bcl-2 (n = 70) compared to those who were considered Bcl-2 negative (n = 27). CONCLUSION: High levels of Bcl-2 protein expression do not appear to be of prognostic significance in non-GCB DLBCL and therefore Bcl-2 may not be a key therapeutic target in the treatment and improvement of clinical outcome in such cases.

Efficacy and safety of zanubrutinib plus R-CHOP in treatment of non-GCB DLBCL with extranodal involvement.

Introduction: Treatment with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) shows poor response rates in non-germinal center B cell-like (non-GCB) diffuse large B-cell lymphoma (DLBCL) patients with multiple extranodal involvement. This study aims to evaluate anti-tumor activity and safety of zanubrutinib with R-CHOP (ZR-CHOP) in treatment naïve non-GCB DLBCL with extranodal involvement. Methods: In this single-arm, phase 2, prospective, single-center study, patients with newly diagnosed non-GCB DLBCL with extranodal involvement enrolled between October 2020 to March 2022 received ZR-CHOP for 6 cycles followed by 2 cycles of maintenance treatment with rituximab and zanubrutinib. The primary endpoint included progression-free survival (PFS) in the intent-to-treat (ITT) population whereas the secondary endpoints included overall response rate (ORR), complete response (CR), and duration of response. Further, next-generation sequencing (NGS) was used for detection of different oncogenic mutations closely related to DLBCL pathogenesis. Results: From October 2020 to March 2022, 26 patients were enrolled, and 23 of them were evaluated for efficacy after receiving 3 cycles of ZR-CHOP treatment. 1-year PFS and OS were 80.8% and 88.5% respectively while expected PFS and OS for 2-years are 74.0% and 88.5% respectively with median follow-up of 16.7 months and ORR was 91.3% (CR: 82.61%; PR: 8.70%). Oncogenic mutations closely related to DLBCL pathogenesis were assessed in 20 patients using NGS. B-cell receptor and NF-κB pathway gene mutations were detected in 10 patients, which occurred in MYD88 (7/19), CD79B (4/19), CARD11 (5/19), and TNFAIP3 (2/19). Hematological adverse events (AEs) ≥ grade 3 included neutropenia (50%), thrombocytopenia (23.1%), and anemia (7.7%) whereas non-hematological AEs ≥ grade 3 included pulmonary infection (19.2%). Conclusion: ZR-CHOP is safe and effective for treating treatment naïve non-GCB DLBCL patients with extranodal involvement. Clinical Trial Registration: Clinicaltrials.gov, NCT04835870.

A Multicenter Study of Clinicopathology and Immunohistochemical Distinction between Adult and Pediatric Large B-Cell Lymphoma.

Introduction: Pediatric DLBCL is considered a homogenous group and has superior outcomes compared to adults. This study investigated the clinical pathology and immunohistochemical distinction between adult and pediatric large B-cell lymphoma. Methods: A cross-sectional study of 314 NHLs with the morphology of diffuse pattern, large B-cell, and CD20 expression was investigated. Results: Of 314 cases, there were 6 cases of pleomorphic MCL (all in adults), 19 cases of Burkitt lymphoma (all in children), and 289 cases of DLBCL. Pediatric DLBCL had many striking differences: More frequency in extra-nodal sites; a higher proportion of centroblastic morphology; a predominance of GCB-type; a high proliferation rate; an infrequency of Bcl2 protein expression, and a lack of double-expresser lymphoma. Conclusions: Our study demonstrated the significant biological differences between adult and pediatric DLBCL.

Treatment Outcomes and Clinical Relevance in Patients with Double Expressor DLBCL.

BACKGROUND: Double-expressor lymphoma (DEL) was found to account for 20-30% of DLBCL. We conducted this study to analyze the survival, the clinical presentation, and the factors associated with treatment outcomes in DEL-DLBCL. METHODS: A retrospective study of 291 patients diagnosed with DLBCL during January 2015 - December 2018 was conducted. RESULTS: Of the 291 patients, the median age was 63 years, germinal center B cell-like DLBCL (GCB) and non-GCB subtypes were found in 32% and 68%, respectively. DEL was found in 46% of 264 patients with available immunohistochemistry staining for MYC protein. Patients with DEL was significantly more common in elderly patients (p= 0.017) and non-GCB subtype (p= 0.006). High serum lactate dehydrogenase (LDH) levels and high Ki-67 index were significantly found in DEL patients than non-DEL patients (p= 0.024 and p= 0.04, respectively). The 3y-OS rate was shorter in the DEL group than in the non-DEL group, 58.7% versus 78.9% (p=0.026), whereas no significant difference in 3y-DFS was identified between these groups (58.4% versus 67.7%, p= 0.343). Independent factors affecting OS and DFS in DEL patients were ECOG 3-4, high LDH levels, extranodal involvement> 1 site, high IPI, and stage III-IV in univariate analysis. CONCLUSIONS: High incidence of DEL was observed in this study, especially in patients aged 60 years or older and non-GCB subtype. Patients with DEL showed dismal DFS and OS.

t(9;14)(p13;q32)/PAX5-IGH translocation as a secondary cytogenetic abnormality in diffuse large B-cell lymphoma.

A 75-year-old man presented with an ileocecal tumor composed of diffuse proliferation of large cells with immunoblastic morphology. Lymphoma cells were positive for CD20, CD79a, IRF4/MUM1, and BCL2, negative for CD5, CD10, and MYC, and partially positive for BCL6. PAX5 was positive with variable staining intensity among the cell nuclei. The V-D-J sequence of IGH showed the mutated configuration. The G-banding karyotype demonstrated two cytogenetic clones with or without t(9;14)(p13;q32), but the two shared other structural and numerical abnormalities. Fluorescence in situ hybridization using PAX5 and IGH probes confirmed the presence or absence of t(9;14)(p13;q32)/PAX5-IGH in each clone. The breakpoints of t(9;14)(p13;q32) were mapped 2,170 bp upstream of the coding region of PAX5 alternative exon 1B and within the IGHJ6-Eµ enhancer intron of IGH. It is suggested that t(9;14)(p13;q32) in this case was a secondary cytogenetic abnormality and the translocation is not necessarily involved in initial malignant transformation of B-cells but can occur later during the course of diffuse large B-cell lymphoma.

Proteomic analysis in diffuse large B-cell lymphoma identifies dysregulated tumor microenvironment proteins in non-GCB/ABC subtype patients.

The complexity of the activated B-cell like (ABC) diffuse large B-cell lymphoma (DLBCL) subtype is probably not only explained by genetic alterations and methods to measure global protein expression could bring new knowledge regarding the pathophysiology. We used quantitative proteomics to analyze the global protein expression of formalin-fixed paraffin-embedded (FFPE) tumor tissues from 202 DLBCL patients. We identified 6430 proteins and 498 were significantly regulated between the germinal center B-cell like (GCB) and non-GCB groups. A number of proteins previously not described to be upregulated in non-GCB or ABC DLBCL was found, e.g. CD64, CD85A, guanylate-binding protein 1 (GBP1), interferon-induced proteins with tetratricopeptide repeat (IFIT)2, and mixed lineage kinase domain-like protein (MLKL) and immunohistochemical staining showed higher expression of GBP1 and MLKL. A cluster analysis revealed that the most prominent cluster contained proteins involved in the tumor microenvironment and regulation of the immune system. Our data suggest that the therapeutic focus should be expanded toward the tumor microenvironment in non-GCB/ABC subtype patients.

High-Grade B-Cell Lymphoma (HGBL) with MYC and BCL2 and/or BCL6 Rearrangements Is Predominantly BCL6-Rearranged and BCL6-Expressing in Taiwan.

This study investigated the epidemiological and clinical peculiarities of BCL2 and BCL6 rearrangement in patients with high grade B-cell lymphoma (HGBL) from Taiwan, compared with data from Western countries. Two hundred and eighty-two DLBCL cases from Taipei Medical University-affiliated hospitals (n = 179) and Tri-Service General Hospital (n = 103) were enrolled for this study. From the 282, 47 (16.7%) had MYC translocation; 24 of these harbored concurrent BCL2 and/or BCL6 translocation (double-hit, DH or triple-hit, TH). Twelve DH-HGBL cases had simultaneous MYC and BCL6 translocations, 8 harbored MYC and BCL2 rearrangement, while the remaining 4 patients exhibited TH. Together, 66.7% of DH/TH-HGBL patients were BCL6 rearrangement positive. Among these BCL6-rearranged DH/TH-HGBL patients, only 6 (37.5%) overexpressed MYC and BCL6 proteins simultaneously, indicating that MYC-BCL6 co-overexpression may not be plausible surrogate biomarker for screening BCL6-rearranged DH-HGBL. By the end of year 5, all patients with TH-HGBL, BCL2 DH-HGBL and all but one BCL6 DH-HGBL cases had expired or were lost to follow-up. Progression-free survival (PFS) was longer for the non-DH/TH-HGBL group compared with the DH/TH-HGBL group. While the patients with BCL2 DH-HGBL were lost to follow-up by day 800, their remaining TH-HGBL and BCL6 DH-HGBL peers exhibited very poor PFS, regardless of age strata. More so, patients with BCL6 rearrangement were 5.5-fold more likely associated with extranodal involvement compared with their BCL2-rearranged peers. Moreover, ~60.0% of the BCL6-rearranged DH-HGBL cases were non-GCB, suggesting that including screening for BCL6 rearrangement in patients with the non-GCB phenotype may aid medical decision-making and therapeutic strategy. Contrary to contemporary data from western countries, 2 in every 3 patients with DH/TH-HGBL in Taiwan harbor BCL6 rearrangement. Consistent with present findings, we recommend mandatory screening for BCL6 rearrangement in patients with aggressive HGBL in Taiwan.

Treatment outcome and prognostic factors in PCNSL.

OBJECTIVES: Standard treatment with a thiotepa-based regimen in countries with a limited resource is less feasible. Aims of the study were to evaluate the treatment outcome, and identify the prognostic factors in patients with primary central nervous system lymphoma (PCNSL). METHODS: We conducted a retrospective study of 43 patients diagnosed with PCNSL, DLBCL subtype, who were treated with either HDMTX-based regimen, whole brain radiotherapy (WBRT), or both between 2010 and 2017. RESULTS: There were 43 patients with a median age of 65 years (range 34-89 years). Protein expression of CD10, Bcl6, MUM1, Bcl2 and MYC were found in 19, 86, 91, 91 and 23%, respectively. Both germinal center B cell (GCB) and double-expressor (MYC+/Bcl2+) lymphomas were found in 21%. Multiple brain lesions and maximum tumor diameter (MTD) ≥5 cm were seen in 27 and 10 patients, respectively. Chemotherapy combined with WBRT, chemotherapy and WBRT were given to 20, 14 and 9 patients, respectively. Overall complete remission (CR) rate was 55.8%. Those receiving a combined-modality therapy had a higher CR rate than those treated with either chemotherapy (75% versus 36%, p = 0.036) or WBRT (75% versus 44%, p = 0.109). Median follow-up time was 17 months, and a 7-year overall survival (OS) was 40%. Features associated with a prolonged OS were an ECOG score ≤ 2 (p = 0.001), multiple brain lesions (p = 0.010), multiple area of brain involvement (p = 0.023), MTD < 5 cm (p = 0.004), GCB subtype (p = 0.003) and positive CD10 staining (p = 0.007). Expression of Bcl2 protein was associated with a significantly worse OS in the non-GCB DLBCL patients. DISCUSSION: The factors affecting treatment outcomes in PCNSL were cell of origin of DLBCL, lesion characteristics, patients' status and treatment regimen.

The prognostic impact of hypermethylation for a panel of tumor suppressor genes and cell of origin subtype on diffuse large B-cell lymphoma.

Diffuse Large B-cell lymphoma (DLBCL) is an aggressive disease with heterogeneous outcome and marked variable response to chemotherapy. We assessed promoter hypermethylation (PM) for a panel of tumor suppressor genes in 75 DLBCLs compared to 20 lymphoid hyperplasia (LH) and 30 normal control, using methylation specific PCR. Results were correlated to patients' clinic-pathological characteristics, immunophenotyping, and patients' outcome. DAPK1, RUNX3, MT1G, MGMT, CDH1 and p16 PM were detected in 38.7% (29/75), 49.3% (37/75), 46.7% (35/75), 44% (33/75), 49.3% (37/75) and 42.7% (32/75);respectively, of DLBCL patients compared to LH group (P < 0.05). Aberrant PM of RUNX3, MGMT, CDH1 and p16 was significantly higher in non-germinal central B-cell like (non-GCB) compared to GCB (58.3% vs. 33.3%, 56.2% vs. 22.2, 62.5% vs. 25.9, and 56.2% vs. 18.5%, respectively). PM of studies genes in DLBCL associated significantly with worse survival outcome and resistance to chemotherapy (P ≤ 0.01). In non-GCB group, DAPK1, MT1G, RUNX3, CDH1 and p16 PM associated significantly with reduced DFS (P ≤ 0.004) and OS (P ≤ 0.015). Multivariate analysis indicated that RUNX3 and CDH1 PM were independent prognostic factors for OS (P = 0.03 and 0.04; respectively), while DAPK1, RUNX3 and MT1G PM were independent prognostic factors for DFS (P = 0.002, 0.037& 0.007; respectively). DAPK1, RUNX3, MT1G, CDH1 and p16 PM are promising prognostic and/or predictive markers for non-GCB independent of IPI. Upregulation of those genes using new demethylating agents is a promising approach that sensitize chemoresistant DLBCL patients, especially the non-GCB subtype.

Impact of Double Expression of C-MYC/BCL2 Protein and Cell of Origin Subtypes on the Outcome among Patients with Diffuse Large B-Cell Lymphoma: a Single Asian Center Experience

Background: Diffuse large B-cell lymphoma (DLBCL) with double expression of c-MYC and BCL2 protein is associated with dismal outcome after treatment with R-CHOP. Local data on disease burden and survival outcome in DLBCL is limited. We investigated the prognostic values of c-MYC/BCL2 protein co-expression and cell of origin subtypes using immunohistochemistry (IHC) and to determine their associations with multiethnic groups under resource limited setting. Methods: This was a retrospective study which recruited 104 patients in between June 2012 and December 2015 for IHC review and analysis. Result: We demonstrated that patients with high International Prognostic Index (IPI) (score 3-5) and co-expression of c-MYC/BCL2 protein had significant inferior overall survival (OS) and event free survival (EFS) respectively (P<0.05). c-MYC/BCL2 protein co-expression was more common in non-germinal center B-cell (non-GCB) (P=0.048) and contributed to adverse prognosis in this group of patients (OS, P=0.004; EFS, P=0.005). In multivariate analysis, double-protein co-expression was a significant independent predictor of inferior outcome after adjusted for IPI and cell of origin subtypes (OS hazard ratio [HR], 2.11; 95% CI, 1.01 to 4.04; P=0.048; EFS HR, 2.31; 95% CI, 1.05 to 5.04; P=0.036). In addition, non-GCB subtype was more common than GCB in Malays (60% vs 40%, P=0.106) and Chinese (81.2% vs 18.8%, P=0.042). Indians had more DLBCL without c-MYC/ BCL2 protein co-expression compared to double-protein positive cases (66.7% vs 33.3%, P=0.414). Otherwise, the prognostic impact of ethnicity on survival outcome was insignificant (P=0.961). Conclusion: c-MYC/BCL2 protein co-expression in non-GCB subtype constituted a unique group with extremely inferior outcome regardless of ethnicity. Gene expression profile (GEP) may possibly provide insights into the cause of discrepancies in DLBCL subtypes and protein expression among the multiethnic groups.

Should We Use Cell of Origin and Dual-protein Expression in Treating DLBCL?

Treatment outcomes in diffuse large B-cell lymphoma (DLBCL) following standard R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) therapy is highly variable and dependent on a number of clinical, biologic, and genetic features. The identification of molecular heterogeneity via gene expression profiling dichotomizes patients based on the cell of origin (COO) model into germinal center B-cell-like (GCB) and activated B-cell-like (ABC) subsets, with ABC-DLBCL having a worse outcome. Along with the COO classification, other molecular phenotypes have also been identified, further highlighting the clinical and biologic complexity of this disease. Double-hit lymphomas, with concurrent chromosomal translocations of the MYC and BLC2 genes, or less commonly MYC and BCL6 genes, are associated with an aggressive clinical course and adverse outcomes when treated with R-CHOP. Furthermore, dual overexpression of MYC and BCL2 proteins has emerged as an important adverse prognostic factor, can be present through different mechanisms in both GCB and ABC subsets, and further complicates treatment considerations. Studies investigating the biologic underpinnings of these diverse subtypes have revealed a number of novel targets, which may provide therapeutic benefit. Moving forward, clinical trials focusing on molecular subsets of DLBCL, and incorporating rational targeted agents, will ideally lead to improved outcomes and allow a more personalized treatment approach. This review will focus on emerging data regarding DLBCL management based on either COO or dual overexpression of MYC/BCL2 proteins.

Successful experience of treatment of a patient with generalized non-GCB- DLBCL using the R-mNHL-BFM-90 protocol with lenalidomide: case report and review of literature.

Diffuse large B-cell lymphoma is categorized by gene expression profiling into germinal center (GCB) and activated B-cell (ABC) subtype, also referred to as non-germinal center B-cell (non-GCB) by immunohistochemistry. ABC DLBCL is characterized by NF-κB pathway activation and high expression of IRF4/MUM1, a key transcription factor in B cell differentiation. Patients with ABC DLBCL have a significantly worse outcome when treated with standard chemotherapy (R-CHOP). Lenalidomide have shown activity in the ABC-DLBCL in combination with R-CHOP. But about 40% of patients remain resistant. We present the experience of treatment of a patient with generalized non-GCB-DLBCL using the intensive protocol R-mNHL-BFM-90 with lenalidomide.

Stratifying diffuse large B-cell lymphoma patients treated with chemoimmunotherapy: GCB/non-GCB by immunohistochemistry is still a robust and feasible marker.

Diffuse large B cell lymphoma (DLBCL) is a heterogeneous group of aggressive lymphomas that can be classified into three molecular subtypes by gene expression profiling (GEP): GCB, ABC and unclassified. Immunohistochemistry-based cell of origin (COO) classification, as a surrogate for GEP, using three available immunohistochemical algorithms was evaluated in TMA-arranged tissue samples from 297 patients with de novo DLBCL treated by chemoimmunotherapy (R-CHOP and R-CHOP-like regimens). Additionally, the prognostic impacts of MYC, BCL2, IRF4 and BCL6 abnormalities detected by FISH, the relationship between the immunohistochemical COO classification and the immunohistochemical expression of MYC, BCL2 and pSTAT3 proteins and clinical data were evaluated. In our series, non-GCB DLBCL patients had significantly worse progression-free survival (PFS) and overall survival (OS), as calculated using the Choi, Visco-Young and Hans algorithms, indicating that any of these algorithms would be appropriate for identifying patients who require alternative therapies to R-CHOP. Whilst MYC abnormalities had no impact on clinical outcome in the non-GCB subtype, those patients with isolated MYC rearrangements and a GCB-DLBCL phenotype had worse PFS and therefore might benefit from novel treatment approaches.

Prognostic impact of B-cell lymphoma 6 in primary CNS lymphoma.

BACKGROUND: We investigated the prognostic significance of B-cell differentiation status and common B-cell differentiation markers in a post hoc analysis of 119 patients with primary CNS lymphoma (PCNSL) homogeneously receiving high-dose methotrexate (HDMTX)-based chemotherapy within the prospective G-PCNSL-SG1 trial. METHODS: We evaluated protein expression of B-cell lymphoma 2 (BCL2), BCL6, CD10, and multiple myeloma oncogene 1/interferon regulatory factor 4 (MUM1/IRF4) by immunohistochemistry and analyzed the association with survival. RESULTS: The median follow-up of all patients was 67.5 months. Median progression-free survival (PFS) was 10.61 months (95% CI: 4.23-17.00). Median overall survival (OS) was 28.85 months (95% CI: 17.96-39.73). Eighty-nine tumors expressed BCL2 (92.7%), 24 (20.5%) expressed CD10, 60 (54.1%) expressed BCL6, and 87 (79.0%) expressed MUM1/IRF4. On the basis of the Hans algorithm, 80 tumors (73.4%) were classified to the non-germinal center B group, suggesting a post-germinal center origin of PCNSL. Expression of BCL6 (cutoff point 30%), but none of the other markers, was associated with shorter PFS (P = .047) and OS (P = .035). On multivariate analysis, BCL6 expression was associated with shorter PFS (hazard ratio: 1.95, 95% CI: 1.22-3.12, P = .005) but not OS (hazard ratio: 1.85, 95% CI: 0.71-4.80, P = .21). Classification according to Hans algorithm and expression status of the single B-cell markers BCL2, CD10, and MUM1/IRF4 did not correlate with prognosis. CONCLUSION: The findings are limited by the fact that only 23% of all G-PCNSL-SG1 patients could be included in the analysis. If validated in an independent cohort, BCL6 may assume clinical relevance as an unfavorable prognostic biomarker in PCNSL.

Prognostic effect of Ki-67 expression in rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone-treated diffuse large B-cell lymphoma is limited to non-germinal center B-cell-like subtype in late-elderly patients.

This study evaluated the effect of age and cell of origin on the prognostic significance of Ki-67 labeling index (Ki-67 LI) on overall survival (OS) of diffuse large B-cell lymphoma (DLBCL) in a cohort of 697 patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP). Multivariate analysis revealed no prognostic significance of high Ki-67 LI (≥ 85%) for OS. However, on subgroup analysis, high Ki-67 LI was significantly associated with poor OS in late-elderly patients (aged ≥ 70 years) (p = 0.021) and non-germinal center B-cell-like (GCB) subtype (p = 0.015). In particular, high Ki-67 LI was associated with a poor prognosis in late-elderly patients with non-GCB subtype. No correlation was observed in young adults (aged < 60 years) or early-elderly (aged 60-70 years) patients or GCB subtype. The present study shows that high Ki-67 LI is a risk factor for poor OS in the late-elderly age group and non-GCB subtype in patients with DLBCL treated with R-CHOP.

Prognostic value of immunohistochemical biomarkers at different cut-off values in patients with diffuse large B-cell lymphoma treated with CHOP chemotherapy.

Many predictive models have been proposed for better stratification of diffuse large B-cell lymphoma (DLBCL). Hans' algorithm has been widely used as standard to sub-classify DLBCL into germinal center B-cell (GCB) and non-GCB origins. However, there have been disagreements in the literature regarding its prognostic significance. Here, we retrospectively analyzed Hans' algorithm and the individual immunohistochemical biomarkers at different cut-off values (5%, 30%, 50% or 75%) in 94 Korean patients with DLBCL treated with combination chemotherapy with cyclophosphamide, daunorubicin, vincristine, and prednisone. No significant differences were observed between the GCB (18 patients, 19.1%) and non-GCB (76, 80.9%) groups. Among individual biomarkers, CD10 negativity (cut point: 30%) and bcl-6 positivity (cut point: 5%) were independent good prognostic markers in progression-free survival (PFS), whereas bcl-6 (cut point: 5%) positivity was an independent good prognostic marker in overall survival irrelevant of international prognostic index. The present study showed the lack of predictability of Hans' algorithm in DLBCL patients, and that CD10, Bcl-6 may have diverse prognostic significance at different cut-off values. Our results suggest that the proposed cut-off value may not be applied universally, and that the optimal cut-off value may need to be optimized for individual laboratory.