A human lymphoma organoid model for evaluating and targeting the follicular lymphoma tumor immune microenvironment.

Heterogeneity in the tumor microenvironment (TME) of follicular lymphomas (FLs) can affect clinical outcomes. Current immunotherapeutic strategies, including antibody- and cell-based therapies, variably overcome pro-tumorigenic mechanisms for sustained disease control. Modeling the intact FL TME, with its native, syngeneic tumor-infiltrating leukocytes, is a major challenge. Here, we describe an organoid culture method for cultivating patient-derived lymphoma organoids (PDLOs), which include cells from the native FL TME. We define the robustness of this method by successfully culturing cryopreserved FL specimens from diverse patients and demonstrate the stability of TME cellular composition, tumor somatic mutations, gene expression profiles, and B/T cell receptor dynamics over 3 weeks. PDLOs treated with CD3:CD19 and CD3:CD20 therapeutic bispecific antibodies showed B cell killing and T cell activation. This stable system offers a robust platform for advancing precision medicine efforts in FL through patient-specific modeling, high-throughput screening, TME signature identification, and treatment response evaluation.

Recurrent and persistent fever after SARS-CoV-2 infection in patients with follicular lymphoma: A case series.

Although persistent or recurrent COVID-19 infection is well described in some immunosuppressed patient cohort, to date, there have been no reports of this phenomenon in the context of repeatedly negative SARS-CoV-2 testing in the upper respiratory tract. We reported six patients with follicular lymphoma who developed recurrent symptomatic COVID-19 infection. They tested persistently negative for SARS-CoV-2 on pharyngeal swabs and ultimately confirmed by bronchoalveolar lavage fluid metagenomics next-generation sequencing. All six patients presented with lymphopenia and B-cell depletion, and five of them received the anti-cluster of differentiation 20 treatment in the last year. Persistent fever was the most common symptom and bilateral ground-glass opacities were the primary pattern on chest computed tomography. A relatively long course of unnecessary and ineffective antibacterial and/or antifungal treatments was administered until the definitive diagnosis. Persistent fever subsided rapidly with nirmatrelvir/ritonavir treatment. Our case highlighted that recurrent COVID-19 infection should be suspected in immunocompromised patients with persistent fever despite negative pharyngeal swabs, and urgent bronchoalveolar lavage fluid testing is necessary. Treatment with nirmatrelvir/ritonavir appeared to be very effective in these patients.

The asymptomatic follicular lymphoma (AFL) trial: single-agent rituximab immunotherapy versus 90Y-ibritumomab tiuxetan radioimmunotherapy (RIT) for patients with new, untreated follicular lymphoma.

Patients with asymptomatic follicular lymphoma (AFL) are candidates for observation or immunotherapy. Given the effectiveness of radiation therapy in FL, another option is 90Yttrium-ibritumomab tiuxetan radioimmunotherapy (RIT). We conducted a trial where untreated AFL patients were randomized to rituximab 375 mg/m2 weekly × 4 or rituximab 250 mg/m2 days 1, 8, and 0.4 mCi/kg (maximum 32 mCi) of RIT day 8. Twenty patients were enrolled before the study was halted due to unavailability of RIT. The ORR for rituximab and RIT were 90% and 80%, respectively; the CR rate at 6 months was 30% and 60%, respectively. After a median follow-up of 67 months, eight patients have progressed-three in the rituximab arm and five in the RIT arm and five have required systemic therapy. All patients remain alive. Both agents are highly active for AFL. The 1-week treatment with RIT and sparing of T-cells make combination therapy with newer agents attractive.

FLI-1 is expressed in a wide variety of hematolymphoid neoplasms: a special concern in the differential diagnosis.

Friend Leukemia Virus Integration 1 (FLI-1) is a member of E26 transformation-specific family of transcription factors that participates in hematopoietic and vascular endothelial cell development. Immunohistochemical detection of FLI-1 has been widely used to diagnose vascular tumors or, more evidently, Ewing's sarcoma. However, the expression pattern of FLI-1 in hematolymphoid neoplasms remains unclear. Therefore, in this study, we aimed to investigate the expression of FLI-1 in these tumors, focusing on high-grade lesions, which presents a diagnostic challenge by mimicking Ewing's sarcoma. We evaluated the expression FLI-1 in various types of lymphoid and plasmacytic tumors, including 27 plasmablastic lymphomas, 229 diffuse large B-cell lymphomas, 22 precursor T- or B-lymphoblastic lymphomas, 24 angioimmunoblastic-type nodal T-follicular helper cell lymphomas, 52 peripheral T-cell lymphomas, NOS, 18 Burkitt lymphomas, 18 non-gastric lymphomas of mucosa-associated lymphoid tissue, 38 chronic lymphocytic leukemia/small lymphocytic lymphomas, 15 mantle cell lymphomas, 23 gastric MALT lymphomas, 50 plasma cell myelomas, and 38 follicular lymphomas. We calculated the H-scores of FLI-1 immunostaining, ranging from 0 to 200, and used the scores to analyze the clinicopathological significance of FLI-1 statistically. FLI-1 was expressed to varying degrees in all types of hematological tumors. FLI-1 expression was detected in 84.1% of patients (466/554). FLI-1 was highly expressed in precursor T- or B-lymphoblastic lymphomas. Follicular lymphomas exhibited low FLI-1 expression. In plasmablastic lymphoma, 85.2% of the patients were focally positive for FLI-1. FLI-1 expression did not correlate with clinicopathological variables, such as demographic data or disease stage, in patients with plasmablastic lymphoma and diffuse large B-cell lymphoma. However, FLI-1 overexpression was associated with poorer overall survival in patients with plasmablastic lymphoma. This study demonstrates that FLI-1 is expressed in various hematolymphoid neoplasms. FLI-1 expression can lead to diagnostic confusion, especially in small blue round cell tumors, such as lymphoblastic lymphoma, plasmablastic lymphoma, and plasma cell myeloma, when distinguishing tumors positive for CD99 and CD56 without CD3, CD20, or CD45. Our findings also suggested the possibility of FLI-1 as a potential prognostic biomarker for plasmablastic lymphoma.

In Situ Follicular B-Cell Neoplasm Presenting as Miliary Facial Papules: A Unique Clinical Presentation and Spontaneous Regression.

ABSTRACT: In situ follicular B-cell neoplasm (ISFN) is a variant of follicular lymphoma, presenting as an incidental histologic finding in lymph node biopsy or excisional specimens. ISFN presents with a B-cell population that strongly expresses BCL2 and CD10 within the germinal centers of a lymph node or extranodal site. Genetic analysis shows t(14;18) translocation. Herein, we report a case of ISFN presenting as military and agminated facial papules in a young woman, which resolved spontaneously in the postpartum period. To our knowledge, this is the only report of a cutaneous site of involvement of this rare entity.

Impact of age on long-term relative survival benefit of radiotherapy for early-stage grade I-II follicular lymphoma from the SEER database (2000-2015).

The aim of this study was to investigate the effect of age on long-term mortality and net survival benefit of radiotherapy (RT) for early-stage grade I-II FL. Five thousand three hundred and five patients with early-stage grade I-II FL in the SEER database (2000-2015) were identified. Primary therapy included RT alone (RT, 20.7%), chemotherapy alone (CT, 27.6%), combined modality therapy (CMT, 5.9%), and observation (45.8%). Inverse probability of treatment weighting (IPTW) was conducted to balance the treatment arms. Relative survival (RS), the standardized mortality ratio (SMR), and transformed Cox regression were used to compare survival differences between treatments. RT with or without CT had significantly higher 10-year OS (approximately 78%) and RS (>95%), but lower SMR (1.47-1.76), compared with CT (67.8%; 86.3%; 2.35; ps < .001), observation (70.2%; 91.2%; 1.82; ps < .05). RT was an independent predictor of better OS and RS in multivariate analyses (p < .001). No significant interaction between age and RT was identified for RS (Pinteraction = .509) or OS (Pinteraction = .769), indicating similar survival benefits across all-ages patients. RT was associated with long-term OS and net survival benefits in patients with early-stage grade I-II FL, irrespective of age.HighlightsThe pattern and incidence of mortality varied by age-group as elderly patients often die of other diseases other than FL beyond 5 years.Radiotherapy was associated with higher long-term OS/RS and better SMR compared with other approaches, regardless of age.

Prognostic relevance of clonal hematopoiesis in myeloid neoplastic transformation in patients with follicular lymphoma treated with radioimmunotherapy.

While novel radioisotope therapies continue to advance cancer care, reports of therapy-related myeloid neoplasms (t-MN) have generated concern. The prevalence and role of clonal hematopoiesis (CH) in this process remain to be defined. We hypothesized that: (i) CH is prevalent in relapsed follicular lymphoma and is associated with t-MN transformation, and (ii) radiation in the form of radioimmunotherapy (RIT) plays a role in clonal progression. In this retrospective cohort study, we evaluated the prevalence and prognostic impact of CH on clinical outcomes in 58 heavily pre-treated follicular lymphoma patients who received RIT. Patients had been given a median of four lines of therapy before RIT. The prevalence of CH prior to RIT was 46%, while it was 67% (P=0.15) during the course of RIT and subsequent therapies in the paired samples. Fourteen (24%) patients developed t-MN. Patients with t-MN had a higher variant allele fraction (38% vs. 15%; P=0.02) and clonal complexity (P=0.03) than those without. The spectrum of CH differed from that in age-related CH, with a high prevalence of DNA damage repair and response pathway mutations, absence of spliceosome mutations, and a paucity of signaling mutations. While there were no clear clinical associations between RIT and t-MN, or overall survival, patients with t-MN had a higher mutant clonal burden, along with extensive chromosomal abnormalities (median survival, afer t-MN diagnosis, 0.9 months). The baseline prevalence of CH was high, with an increase in prevalence on exposure to RIT and subsequent therapies. The high rates of t-MN with marked clonal complexities and extensive chromosomal damage underscore the importance of better identifying and studying genotoxic stressors accentuated by therapeutic modalities.

Analysis of immunophenotypic features in hyaline vascular type Castleman disease.

BACKGROUND: Studies suggested that the immunophenotype of hyaline vascular type Castleman disease (HVCD) lacked characteristics, which was easy to be confused with other diseases. METHODS: From January 2010 to June 2022, 17 cases of HVCD were selected from the Department of Pathology of Shaanxi Provincial People's Hospital and the Department of Pathology of Shaanxi Provincial Cancer Hospital. 13 cases of reactive hyperplastic lymph nodes (RHL) and 11 cases of follicular lymphoma (FL) were selected as the control group. All cases were performed CD3, CD20, CD21 and BCL2 immunohistochemical staining. RESULTS: (i) In 17 cases of HVCD, the negative area of BCL2 of germinal center was significantly smaller than the negative area of CD3 of germinal center. However, in 13 cases of RHL, the negative area of CD3 of germinal center was basically consistent with the negative area of germinal center of BCL2 of germinal center. In 11 cases of FL, in neoplastic follicles, the negative area of CD3 was basically consistent with the positive area of BCL2. The difference between HVCD group and other two groups of diseases was statistically significant (P < 0.05). (ii) In 17 cases of HVCD, the negative area of BCL2 of germinal center was significantly smaller than the follicular dendritic cell (FDC) meshworks expressed by CD21. However, in 13 cases of RHL, the FDC meshworks expressed by CD21 were basically consistent with the negative area of BCL2 of germinal center. In 11 cases of FL, in neoplastic follicles, the FDC meshworks expressed by CD21 was basically consistent with the positive area of BCL2. The difference between HVCD group and other two groups of disease was statistically significant (P < 0.05). CONCLUSIONS: HVCD has unique immunophenotypic characteristics. The negative area of BCL2 of germinal center is significantly smaller than the negative area of CD3. The negative area of the BCL2 of germinal center is significantly smaller than the FDC meshworks expressed by CD21. These two immunophenotypic features in HVCD are very important in diagnosis and differential diagnosis.

Performance of the cobas EZH2 mutation test on clinical samples from non-Hodgkin lymphoma patients.

OBJECTIVE: To present the technical verification and clinical validation of the companion diagnostic assay, cobas® EZH2 Mutation Test (cobas EZH2 Test), targeting gain-of-function EZH2 mutations in follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL). The focus is on patient clinical samples proving that the test met the performance criteria required for FDA approval of a companion diagnostic test. DESIGN: Epizyme, Inc., Eisai Co., Ltd., and Roche Molecular Systems, Inc., collaborated to develop the cobas EZH2 Test on an RT-PCR platform. The assay design needed to detect the gain-of-function EZH2 mutations found in FL and DLBCL indications. Thus, the test was optimized for investigational purposes in a clinical trial setting. Part of its technical verification included testing of patient tumor samples with a documented diagnosis of FL and DLBCL procured from commercial vendors, and the clinical validation used patient samples from the Epizyme clinical study. Both the technical performance verification method correlation study (104 clinical commercially acquired samples) and the clinical validation accuracy study (341 patient samples from the therapeutic study) used next-generation sequencing as a reference method to establish true vs. false results by cobas EZH2 Test. The reproducibility study used a 15-member panel of DNA samples with varying EZH2 mutation status from procured clinical FL and DLBCL patient samples under multiple variables. RESULTS: Single and rare, infrequent double EZH2 mutations were detected in FL and DLBCL samples. Agreements between results from cobas EZH2 and sequencing were >98% from commercial clinical samples and from the therapeutic study clinical samples. The reproducibility study obtained 178 to 180 valid results for each panel member, with an overall invalid rate of 0.37%. The agreement for each per panel member was 100%. CONCLUSION: cobas EZH2 Test data demonstrated that the test is reliable and will perform well in a commercial customer environment.

An Atypical relapsing follicular lymphoma to composite Hodgkin's lymphoma.

Composite lymphoma is defined as two or more lymphomas with distinct morphological and immunophenotypical characteristics synchronously diagnosed at the same anatomical site. Composite lymphoma is rare, and the most common combination is follicular lymphoma (FL) associated with diffuse large B cell lymphoma, followed by FL associated with classic Hodgkin's lymphoma (HL). Histologically, composite lymphomas display a mixed pattern or distinct zonal distribution of each lymphoma component. Composite lymphoma poses a diagnostic challenge, especially when two lymphoma components are mixed in the same lymph node. Here, we report a case of composite HL and FL 11 years after initial and repeat biopsies consistent with FL in a man in his 70s emphasising the importance of repeat biopsy in lymphoma diagnosis.

[Transcriptome analysis of tissue microbiota diversity in tumor and non-tumor lymph nodes]. / Transkriptomnyi analiz raznoobraziya mikrobioty tkanei opukholevykh i neopukholevykh limfaticheskikh uzlov.

BACKGROUND: Metagenomic studies in recent years have demonstrated that all tissues of the human body studied by genomic and transcriptomic sequencing methods, both in pathological processes and in normality, contain fragments of DNA and RNA from a variety of microorganisms. The composition of tissue microbiota and its relationship with development of pathological changes are still poorly understood, despite increasing number of studies in this area every year. In this study, gene expression of the lymph node microbiome in reactive follicular hyperplasia and follicular lymphoma was investigated. OBJECTIVE: To study expression of lymph node microbiome genes in reactive follicular hyperplasia and follicular lymphoma. MATERIAL AND METHODS: The work included 38 biopsy samples of lymph nodes with follicular lymphoma of different cytological subtypes and 10 biopsy samples of lymph nodes with reactive follicular hyperplasia. Verification of diagnosis was carried out using standard histological, histochemical and immunohistochemical methods. Using sequencing method, the transcriptome was examined. Statistical analysis and data visualization were performed using the R programming language (version 4.2.1). RESULTS: Tumor lymph nodes are characterized by large Simpson and Shannon alpha diversity values (p-value = 0.026465 and p-value = 0.007122, respectively). Two clusters were discovered, characterized by different levels of relative abundance of microorganisms. CONCLUSION: It has been proven that diversity of microorganisms present in tumor tissue and their number are statistically significantly higher than corresponding indicators in the lymph nodes with follicular hyperplasia.

[Analysis of 9 cases of pediatric-type follicular lymphoma].

Objective: To summarize the pathological diagnosis, clinical features, treatment methods and outcomes of pediatric-type follicular lymphoma (PTFL). Methods: Clinical data including the pathology, clinical features, treatment methods, and follow-up results of 9 PTFL patients admitted to Henan Cancer Hospital from February 2017 to February 2023 were analyzed retrospectively. Results: The age of onset in 9 children was 6 to 18 years, all the patients were males. The clinical manifestation was local painless lymph node enlargement in the head and neck, with a stage of Ⅰ-Ⅱ. The histomorphological characteristics of PTFL were similar to those of classic follicular lymphoma (FL). The germinal center of most follicles were enlarged, the mantle zone disappeared, centroblasts were easily visible, and the histological grade were mostly grade Ⅲ, which may be accompanied by the "starry sky" phenomenon. Monoclonal peaks can be seen in B cell clonal rearrangements (BCR). Immunohistochemistry (IHC) showed CD20 positive, CD10 positive, Bcl-6 positive, Bcl-2 negative, C-myc negative, and Ki-67 was 70%-95%. Fluorescence in situ hybridization (FISH) test was negative for t (14, 18), Bcl-2 translocation, and C-myc translocation. Six cases underwent surgical resection, and 3 cases underwent surgical resection combined with chemotherapy. Up to February 2023, with a follow-up time of 45 to 72 months, all children survived without any recurrence and were in a complete remission state. Conclusions: PTFL is mainly characterized by adolescent male onset, with early clinical manifestations and pathological manifestations of high-level histological status, high proliferation index, and lack of t (14; 18)/Bcl-2 translocation and Bcl-2 expression. It is mainly treated by localized surgical excision and has a good prognosis.

[CD23 positive, BCL2 rearrangement-negative germinal centre lymphomas]. / CD23-positive, BCL2-Rearrangement-negative Keimzentrumslymphome.

Acknowledgeing that the group of follicular lymphomas is to be regarded as very heterogeneous, a group of follicular lymphomas has been delineated in recent years that was characterised by an often diffuse growth (without formation of evident follicular structures) as well as expression of CD23 in the lymphoma cells and the absence of the classic BCL2 translocation. Further characteristics are a preferred inguinal localisation of the lymphomas and a localised stage with a good prognosis. Genetically, this lymphoma group is characterised by a high rate of either STAT6 or SOCS1 mutations.The ICC classification took this development into account by introducing the provisional entity CD23 positive, BCL2 rearrangement-negative germinal centre lymphoma. Further studies must now show how exactly this entity can be defined (combination of morphology, immunohistochemical phenotype, focus on genetic alterations) in order to pave the way towards a uniform classification and a better clinical characterisation of these cases - especially with regard to possible new therapeutic treatment options.

[Clinical pathological characteristics analysis of ocular adnexal follicular lymphoma].

Objective: To investigate the clinical pathological characteristics of ocular adnexal follicular lymphoma (OAFL). Methods: A retrospective case series study was conducted. Clinical data of 10 OAFL patients diagnosed at Tianjin Eye Hospital from January 1990 to May 2022 were collected. The study analyzed general patient information, medical history, site of involvement, imaging, histopathology, and molecular detection. Among them, 7 cases underwent Epstein-Barr virus-encoded small RNA (EBER) and B-cell lymphoma protein 2 (BCL-2)/immunoglobulin heavy chain gene (IgH) translocation gene detection. Treatment and prognosis of patients were followed up. Results: All 10 patients (10 eyes) had unilateral involvement, including 5 males and 5 females, with an age range of 58 (43, 68) years. Clinical manifestations included eyelid swelling, pink conjunctival thickening, painless slow-growing masses in the lacrimal gland area, extraconal muscle cone, conjunctiva, lacrimal sac, or a combination of lacrimal sac and conjunctiva. Among them, 8 cases were primary, and 2 cases were secondary. According to the Ann Arbor staging, 8 cases were stage Ⅰ-Ⅱ E, and 2 cases were stage Ⅲ E. Histopathological grading revealed 6 cases of grade 1-2 and 3 cases of grade 3A. One case showed grade 3B in the lacrimal sac area and grade 1-2 in the conjunctiva. The predominant subtype was follicular in 4 cases, diffuse in 3 cases, and mixed in 2 cases. One case had a mixed subtype involving the lacrimal sac and conjunctiva. All patients expressed positivity for leukocyte differentiation antigens (CD) 20, CD21, and CD23. Nine cases were positive for CD10, with 1 case showing partial CD10 positivity. All patients were positive for B-cell lymphoma protein 6 (BCL-6), and 9 cases were positive for BCL-2. Specific markers CyclinD1 and Multiple Myeloma Oncogene Protein 1 (MUM-1) were negatively expressed in all cases. The Ki-67 proliferation index ranged from 10% to 90%. Molecular detection was performed in 7 patients, with none showing positive EBER in situ hybridization. However, 5 cases exhibited BCL2/IgH gene fusion. Among 7 patients with follow-up data, the median follow-up time was 17 (6, 34) months. Four patients achieved complete remission, 2 had partial remission, and 1 patient died due to lung infection. Conclusions: OAFL is a tumor originating from follicular center B-cells, characterized by positive expression of BCL-2, CD10, and BCL-6. It can involve the lacrimal gland, extraconal muscles, lacrimal sac, and conjunctiva. Patients generally have a favorable prognosis.

Proteomics identifies apoptotic markers as predictors of histological transformation in patients with follicular lymphoma.

Follicular lymphoma (FL) is an indolent lymphoma with a generally favorable prognosis. However, histological transformation (HT) to a more aggressive disease leads to markedly inferior outcomes. This study aims to identify biological differences predictive of HT at the time of initial FL diagnosis. We show differential protein expression between diagnostic lymphoma samples from patients with subsequent HT (subsequently-transforming FL [st-FL]; n = 20) and patients without HT (nontransforming FL [nt-FL]; n = 34) by label-free quantification nano liquid chromatography-tandem mass spectrometry analysis. Protein profiles identified patients with high risk of HT. This was accompanied by disturbances in cellular pathways influencing apoptosis, the cytoskeleton, cell cycle, and immune processes. Comparisons between diagnostic st-FL samples and paired transformed FL (n = 20) samples demonstrated differential protein profiles and disrupted cellular pathways, indicating striking biological differences from the time of diagnosis up to HT. Immunohistochemical analysis of apoptotic proteins, CASP3, MCL1, BAX, BCL-xL, and BCL-rambo, confirmed higher expression levels in st-FL than in nt-FL samples (P < .001, P = .015, P = .003, P = .025, and P = .057, respectively). Moreover, all 5 markers were associated with shorter transformation-free survival (TFS; P < .001, P = .002, P < .001, P = .069, and P = .010, respectively). Notably, combining the expression of these proteins in a risk score revealed increasingly inferior TFS with an increasing number of positive markers. In conclusion, proteomics identified altered protein expression profiles (particularly apoptotic proteins) at the time of FL diagnosis, which predicted later transformation.

Gene expression and copy number profiling of follicular lymphoma biopsies from patients treated with first-line rituximab without chemotherapy.

The Nordic Lymphoma Study Group has performed two randomized clinical trials with chemotherapy-free first-line treatment (rituximab +/- interferon) in follicular lymphoma (FL), with 73% of patients alive and 38% without any need of chemotherapy after 10.6 years median follow-up. In order to identify predictive markers, that may also serve as therapeutic targets, gene expression- and copy number profiles were obtained from 97 FL patients using whole genome microarrays. Copy number alterations (CNAs) were identified, e.g. by GISTIC. Cox Lasso Regression and Lasso logistic regression were used to determine molecular features predictive of time to next therapy (TTNT). A few molecular changes were associated with TTNT (e.g. increased expression of INPP5B, gains in 12q23/q24), but were not significant after adjusting for multiple testing. Our findings suggest that there are no strong determinants of patient outcome with respect to GE data and CNAs in FL patients treated with a chemotherapy-free regimen (i.e. rituximab +/- interferon).