Digital and manual interfollicular Ki-67 are associated with a progression-free survival in patients with low-grade follicular lymphoma

OBJECTIVES

Novel histopathologic prognostic factors are needed to identify patients with follicular lymphoma (FL) at risk of inferior outcomes. Our primary objective was to evaluate the Ki-67 proliferative index in follicular and interfollicular areas in tissue biopsy specimens from patients with newly diagnosed FL and correlate with clinical outcomes. Our secondary objective was to correlate PD-L1 and LAG-3 with clinical outcomes.

METHODS

Seventy cases of low-grade FL from the University of Minnesota were evaluated with Ki-67 immunohistochemical stain. Ki-67 expression as a continuous variable was interpreted digitally and manually in follicular and interfollicular areas. Progression-free survival (PFS) and overall survival (OS) were analyzed by Cox regression, and hazard ratios (HRs) per 10-point increase in Ki-67 were calculated.

RESULTS

Progression-free survival at 4 years was 28% (95% CI, 19%-41%). Interfollicular, but not follicular, Ki-67 was associated with PFS by manual (HR, 1.33; P = .01) and digital (HR, 1.38; P = .02) analysis. Digital and manual Ki-67 were only moderately correlated but demonstrated similar effects on PFS. At 4 years, OS was 90% with no association with follicular or interfollicular Ki-67 proliferation.

CONCLUSIONS

Higher interfollicular Ki-67 by either digital or manual analysis is associated with a poorer PFS in patients with low-grade FL. These results suggest further validation of this marker is warranted to improve pathologic risk stratification at FL diagnosis. PD-L1 and LAG-3 were not associated with PFS or OS.

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.

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.

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.

Endoscopic observation of a rare duodenal tumor

A 30-year-old young previously healthy man presented to our hospital with middle and upper abdominal discomfort. Abdominal computerized tomography (CT) showed no significant abnormalities. White light endoscopy showed the local mucosa in the descending part of the duodenum had granuloid uplift, some of which were fused into pieces with red color, and some other areas showed fading tone. Magnifying endoscopy with indigo-carmine staining and narrow-band imaging showed a finger-like, loose villous structure with irregular microvessels on the surface. Pathological examination of biopsy specimens showed that lymphocytes were diffused and dispersed in the mucosa with relatively simple morphology, no lymphoid follicles were observed, and local compression was obvious. Immunohistochemical staining revealed a lymphoid population highly positive for CD20 and CD10. These results were consistent with duodenal-type follicular lymphoma (D-FL).

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.

The Detection of Neoplastic Cells Using Objective Cytomorphologic Parameters in Malignant Lymphoma

Pathologic evaluation is the most crucial method for diagnosing malignant lymphomas. However, there are no established diagnostic criteria for evaluating pathologic morphology. We manually circled cell nuclei in the lesions of 10 patients with diffuse large B-cell lymphoma (DLBCL), follicular lymphoma, and reactive lymphadenitis. Seventeen parameters related to nuclear shape, color, and other characteristics were measured. We attempted to compare the statistical differences between these subtypes and extract distinctive disease-specific populations on the basis of these parameters. Statistically significant differences were observed between the different types of lymphoma for many of the 17 parameters. Through t-distributed stochastic neighbor embedding analysis, we extracted a cluster of cells that showed distinctive features of DLBCL and were not found in follicular lymphoma or reactive lymphadenitis. We created a decision tree to identify the characteristics of the cells within that cluster. Based on a 5-fold cross-validation study, the average sensitivity, specificity, and accuracy obtained were 84.1%, 98.4%, and 97.3%, respectively. A similar result was achieved using a validation experiment. Important parameters that indicate the features of DLBCL include Area, ConcaveCount, MaxGray, and ModeGray. By quantifying pathologic morphology, it was possible to objectively represent the cell morphology specific to each lymphoma subtype using quantitative indicators. The quantified morphologic information has the potential to serve as a reproducible and flexible diagnostic tool.

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.

Commentary on small-volume biopsy of follicular lymphoma: Practical issues in the molecular era

Follicular lymphoma (FL) is a common subtype of non-Hodgkin lymphoma derived from germinal center B-cells. Small-volume biopsies (SVBs), including fine-needle aspiration, needle core biopsy, and cell blocks, are often used for the assessment of patients with FL. Recently, Fitzpatrick et al. found that additional biopsies were frequently needed to supplement SVB for the initial diagnosis of FL. However, regardless of the type of SVB used, additional biopsies were usually not necessary for assessments for transformed or recurrent FL. Their multi-institutional study reflects the fact that SVB may be sufficient for clinical decision-making in these medical settings, although surgical excision is the gold standard for a definitive diagnosis of FL. With ancillary tests and advances in molecular testing, SVB has become increasingly popular and helpful, although there are practical limitations.

AN UNUSUAL CASE OF PRIMARY VITREORETINAL LYMPHOMA: A TRANSFORMED LYMPHOMA

PURPOSE

To report a case of primary vitreoretinal lymphoma (VRL) presenting as diffuse large b-cell lymphoma 19 years after initial systemic follicular lymphoma.

METHOD

A case report.

RESULTS

An 81-year-old male patient presented with a 1-month history of floaters and blurry vision in the left eye. He had a history of follicular non-Hodgkin lymphoma treated with systemic chemotherapy in 2002 and prostate cancer treated surgically in 2004. Ophthalmic examination revealed vitritis, retinal whitening, perivascular sheathing, and a vascularized cream-colored retinal mass in the superonasal periphery of the left eye. Diagnostic vitrectomy with retina and vitreous biopsies demonstrated diffuse large b-cell lymphoma. Positron emission tomography/computed tomography confirmed the isolated lesion in the left eye without systemic involvement. Treatment with systemic and intraocular chemotherapy was planned.

CONCLUSION

To the best of our knowledge, this is the first reported case of primary vitreoretinal lymphoma of diffuse large b-cell lymphoma transformed from follicular lymphoma. Intravitreal and systemic chemotherapy, including rituximab, should be considered in the management of patients with transformed vitreoretinal lymphoma.

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.

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.

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.

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.

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.

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.

[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.

Evolution of Lymphoma Diagnosis in the Era of Personalized Medicine: A Marriage of Pathology and Genomics for Clinical Practice

The modern taxonomy of disease builds a framework for precision medicine, by which traditional pathologic criteria are integrated with clinical and genomic features to define disease entities. Two of the most common subtypes of lymphoma on a worldwide basis are follicular lymphoma (FL) and diffuse large B-cell lymphoma. Although BCL2 translocation is the signature lesion of most nodal FL, recent studies have identified significant diversity among follicle center-derived lesions. BCL2-negative FL is a genetically heterogeneous disease that occurs in both nodal and extranodal sites. Several distinct entities have been recognized in the pediatric age group, including pediatric-type FL, testicular FL, and interferon regulatory factor 4 (IRF4)-rearranged large B-cell lymphoma. Diffuse large B-cell lymphoma is a family of aggressive B-cell neoplasms with marked variation in pathogenesis and clinical features. Gene expression profiling >20 years ago identified the cell of origin as a key discriminator, but more recently high-throughput sequencing has identified highly varied mutational profiles that point the way in the future toward improvements in targeted therapy and patient outcome.

[CD23 positive, BCL2 rearrangement-negative germinal centre lymphomas]

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.

Oral follicular lymphoma: a clinicopathologic and molecular study

Follicular lymphoma is a hematolymphoid neoplasm that originates from germinal center B cells. It is made up of a combination of small cleaved centrocytes and a varying quantity of larger non-cleaved centroblasts to describe the clinical, microscopic, immunohistochemical, and molecular features of oral follicular lymphomas. Follicular lymphomas affecting the oral cavity were retrieved from pathology files. Immunohistochemistry was performed to confirm the diagnosis, and fluorescence in situ hybridization (FISH) was employed to detect rearrangements in BCL2, BCL6, and MYC genes. Clinical and follow-up data were obtained from the patient's medical and pathology files. Twenty cases were obtained. There was an equal sex distribution (10 males: 10 females) and a mean age of 60.9 years (range: 10-83 years-old). Lesions presented as asymptomatic swellings, usually in the palate (10 cases) and the buccal mucosa (7 cases). Five patients presented with concomitant nodal involvement. Microscopic evaluation depicted the follicular growth pattern with diffuse areas in six cases. Grades 1 and 2 follicular lymphomas represented 12 cases, while grade 3A neoplasms accounted for other 8 cases. Two cases showed rearrangements in MYC, BCL2, and BCL6 genes, while single BCL2 translocation was found in eight cases. Two cases had no translocation. Three patients deceased and the 2-year overall survival achieved 88%. Follicular lymphoma affecting the oral cavity is uncommon, usually affects the palate as a non-ulcerated swelling and the presence of a systemic disease most always be ruled out.

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).

[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.

The clinical and molecular taxonomy of t(14;18)-negative follicular lymphomas

Follicular lymphoma (FL) is a neoplasm derived from germinal center B cells, composed of centrocytes and centroblasts, with at least a focal follicular growth pattern. The t(14;18) translocation together with epigenetic deregulation through recurrent genetic alterations are now recognized as the hallmark of FL. Nevertheless, FL is a heterogeneous disease, clinically, morphologically, and biologically. The existence of FL lacking the t(14;18) chromosomal alteration highlights the complex pathogenesis of FL, and indicates that there are alternative pathogenetic mechanisms that can induce a neoplasm with follicular center B-cell phenotype. Based on their clinical presentation, t(14;18)-negative FLs can be divided into 3 broad groups: nodal presentation, extranodal presentation, and those affecting predominantly children and young adults. Recent studies have shed some light into the genetic alterations of t(14;18)-negative FL. Within the group of t(14;18)-negative FL with nodal presentation, cases with STAT6 mutations are increasingly recognized as a distinctive molecular subgroup, often cooccurring with CREBBP and/or TNFRSF14 mutations. FL with BCL6 rearrangement shows clinicopathological similarities to its t(14;18)-positive counterpart. In contrast, t(14;18)-negative FL in extranodal sites is characterized mainly by TNFRSF14 mutations in the absence of chromatin modifying gene mutations. FL in children have a unique molecular landscape when compared with those in adults. Pediatric-type FL (PTFL) is characterized by MAP2K1, TNFRSF14, and/or IRF8 mutations, whereas large B-cell lymphoma with IRF4 rearrangement is now recognized as a distinct entity, different from PTFL. Ultimately, a better understanding of FL biology and heterogeneity should help to understand the clinical differences and help guide patient management and treatment decisions.

Mutations associated with progression in follicular lymphoma predict inferior outcomes at diagnosis: Alliance A151303

Follicular lymphoma (FL) is clinically heterogeneous, with select patients tolerating extended watch-and-wait, whereas others require prompt treatment, suffer progression of disease within 24 months of treatment (POD24), and/or experience aggressive histologic transformation (t-FL). Because our understanding of the relationship between genetic alterations in FL and patient outcomes remains limited, we conducted a clinicogenomic analysis of 370 patients with FL or t-FL (from Cancer and Leukemia Group B/Alliance trials 50402/50701/50803, or real-world cohorts from Washington University School of Medicine, Cleveland Clinic, or University of Miami). FL subsets by grade, stage, watch-and-wait, or POD24 status did not differ by mutation burden, whereas mutation burden was significantly higher in relapsed/refractory (rel/ref) FL and t-FL than in newly diagnosed (dx) FL. Nonetheless, mutation burden in dx FL was not associated with frontline progression-free survival (PFS). CREBBP was the only gene more commonly mutated in FL than in t-FL yet mutated CREBBP was associated with shorter frontline PFS in FL. Mutations in 20 genes were more common in rel/ref FL or t-FL than in dx FL, including 6 significantly mutated genes (SMGs): STAT6, TP53, IGLL5, B2M, SOCS1, and MYD88. We defined a mutations associated with progression (MAP) signature as ≥2 mutations in these 7 genes (6 rel/ref FL or t-FL SMGs plus CREBBP). Patients with dx FL possessing a MAP signature had shorter frontline PFS, revealing a 7-gene set offering insight into FL progression risk potentially more generalizable than the m7-Follicular Lymphoma International Prognostic Index (m7-FLIPI), which had modest prognostic value in our cohort. Future studies are warranted to validate the poor prognosis associated with a MAP signature in dx FL, potentially facilitating novel trials specifically in this high-risk subset of patients.

Gastrointestinal Follicular Lymphoma: A Single-institutional Experience of 22 Cases With Emphasis on the Comprehensive Clinicopathological Analysis and Diagnostic Re-classification

BACKGROUND/AIM

Distinguishing gastrointestinal involvement in classic follicular lymphoma (CFL) and duodenal-type follicular lymphoma (DFL) is crucial for proper treatment. This study aimed to describe an integrated diagnostic re-classification of gastrointestinal follicular lymphoma (GIFL) and identify useful features for its differential diagnosis.

PATIENTS AND METHODS

We reviewed radiological and endoscopic images and pathology slides of 22 GIFL cases, not otherwise specified.

RESULTS

Thirteen cases of duodenal grade 1 FL without nodal disease were re-classified as DFL. Five cases of non-duodenal grade 3 FL accompanied by nodal enlargement were re-classified as CFL. The DFL showed peripherally accentuated CD21 immunoreactivity, whereas the CFL showed strong homogeneous CD21 expression. Four atypical cases were re-classified as DFL and CFL in one and three cases, respectively.

CONCLUSION

Our findings support the notion that DFL differs from CFL. In cases of GIFL with atypical features, the possibility of gastrointestinal involvement by CFL should be considered. CD21 expression patterns can assist in the differential diagnosis of CFL and DFL.

Outcomes in grade 3B follicular lymphoma: an international study led by the Australasian Lymphoma Alliance

Grade (G) 3B follicular lymphoma (FL) is a rare FL subtype which exists on a histological continuum between 'lowgrade' (Grade 1, 2 and 3A FL) and diffuse large B-cell lymphoma (DLBCL) appearing to share features with each. Clinical characteristics and outcomes are poorly understood due to lack of adequate representation in prospective trials and large-scale analyses. We analyzed 157 G3BFL cases from 18 international centers, and two comparator groups; G3AFL (n=302) and DLBCL (n=548). Composite histology with DLBCL or low-grade FL occurred in approximately half of the G3BFL cases. With a median of 5 years follow-up, the overall survival and progression-free survival of G3BFL patients was better than that of DLBCL patients (P<0.001 and P<0.001, respectively); however, G3BFL patients were younger (P<0.001) with better performance status (P<0.001), less extranodal disease (P<0.001) and more frequently had normal lactate dehydrogenase (P<0.001) at baseline. The overall and progression-free survival of patients with G3BFL and G3AFL were similar (P=0.83 and P=0.80, respectively). After frontline immunochemotherapy, 24% of G3BFL relapsed; relapse rates were 63% in the DLBCL cohort and 19% in the low-grade FL cohort. Eight percent of relapses occurred beyond 5 years. In this G3BFL cohort, the revised International Prognostic Index successfully delineated risk groups, but the Follicular Lymphoma International Prognostic Index did not. We conclude that patients with immunochemotherapy-treated G3BFL have similar survival outcomes to those with G3AFL, yet a favorable baseline profile and distinctly superior prognosis compared to patients with DLBCL.

External Validation of the FLIPI Risk Score Measured at Diagnosis and POD24 Among Individuals With Follicular Lymphoma at the Time of Subsequent Relapse

BACKGROUND

The Follicular lymphoma international prognostic index (FLIPI) risk score and POD24 have previously been shown to have prognostic value in follicular lymphoma (FL), but the extent to which they can inform prognosis at the time of subsequent relapse is uncertain.

PATIENTS AND METHODS

We conducted a longitudinal cohort study of individuals diagnosed with FL between 2004 and 2010 in Alberta, Canada who received front-line therapy and subsequently relapsed. FLIPI covariates were measured prior to the initiation of front-line therapy. Median overall survival (OS), progression-free survival (PFS2), and time to next treatment (TTNT2) were estimated from the time of relapse.

RESULTS

A total of 216 individuals were included. The FLIPI risk score was highly prognostic at the time of relapse for OS (c-statistic = 0.70; HR[High vs. Low] = 7.38; 95% CI: 3.05-17.88), PFS2 (c-statistic = 0.68; HR[High vs. Low] = 5.84; 95% CI: 2.93-11.62) and TTNT2 (c-statistic = 0.68; HR[High vs. Low] = 5.72; 95% CI: 2.87-11.41). POD24 was not prognostic at the time of relapse for either OS, PFS2, or TTNT2 (c-statistic = 0.55).

CONCLUSION

The FLIPI score measured at diagnosis may help with the risk stratification of individuals with relapsed FL.

A Review of the Flow Cytometric Findings in Classic Hodgkin Lymphoma, Nodular Lymphocyte Predominant Hodgkin Lymphoma and T Cell/Histiocyte-Rich Large B Cell Lymphoma

Classic Hodgkin lymphoma, nodular lymphocyte predominant Hodgkin lymphoma, and T cell/histiocyte-rich large B cell lymphoma form a unique set of lymphomas with similar morphologic growth patterns (occasional neoplastic cells within a prominent cellular cell background) that are pathobiologically related. Distinguishing these entities has been historically difficult by flow cytometry; however, our laboratory has developed antibody-fluorochrome combinations capable of immunophenotyping these lymphomas. Additionally, characterization of the background reactive lymphocytes can aid in narrowing the differential diagnosis. This review summarizes the immunophenotypic features and insights of the neoplastic and reactive populations found in this unique group of lymphomas.

Follicular lymphoma grade 3B: low grade, high grade or should we skip the grade?

Not available.

Donor-Derived Follicular Lymphoma After Kidney Transplantation: A Case Report

Donor-derived follicular lymphoma after kidney transplant revealed by genomic profiling.

Estimating the Lifetime Treatment Burden of Patients With Follicular Lymphoma: A Retrospective Study Using Real-World Multicenter Data

PURPOSE

Although follicular lymphoma is characterized by long natural history and frequent relapses, data on the number of patients receiving subsequent therapy lines are scarce. To perform reliable health economical calculations for various treatment options, data regarding the lifetime number of therapy courses are needed. The purpose of this study was to use real-world data to create a model that could estimate the treatment burden over a 20-year period.

MATERIALS AND METHODS

We performed a 20-year simulation on the basis of retrospectively obtained multicenter data of 743 patients with follicular lymphoma. The simulation was carried out in two steps: First, a competing risk model on the basis of Weibull distribution was used to simulate the state transitions from diagnosis onward and from first-line therapy onward. Then, the data were completed by imputing on the basis of the existing data. Completion of data was repeated for 1,000 times to estimate reliability.

RESULTS

In 20 years, 97% (2.5-97.5 percentile range: 96%-98%), 66% (61%-70%), 34% (30%-41%), and 15% (9%-18%) of the patients received first-line, second-line, third-line, and fourth-line therapies, respectively. The median number of therapy lines received by each patient was two.

CONCLUSION

Despite long remissions, approximately two thirds of the patients receive at least two lines and one-third at least three lines of therapy during their lifetime.

Parallel testing of liquid biopsy (ctDNA) and tissue biopsy samples reveals a higher frequency of EZH2 mutations in follicular lymphoma

BACKGROUND

Recent genomic studies revealed enhancer of zeste homolog 2 (EZH2) gain-of-function mutations, representing novel therapeutic targets in follicular lymphoma (FL) in around one quarter of patients. However, these analyses relied on single-site tissue biopsies and did not investigate the spatial heterogeneity and temporal dynamics of these alterations.

OBJECTIVES

We aimed to perform a systematic analysis of EZH2 mutations using paired tissue (tumor biopsies [TB]) and liquid biopsies (LB) collected prior to treatment within the framework of a nationwide multicentric study.

METHODS

Pretreatment LB and TB samples were collected from 123 patients. Among these, 114 had paired TB and LB, with 39 patients characterized with paired diagnostic and relapse samples available. The EZH2 mutation status and allele burden were assessed using an in-house-designed, highly sensitive multiplex droplet digital PCR assay.

RESULTS

EZH2 mutation frequency was found to be 41.5% in the entire cohort. In patients with paired TB and LB samples, EZH2 mutations were identified in 37.8% of the patients with mutations exclusively found in 5.3% and 7.9% of TB and LB samples, respectively. EZH2 mutation status switch was documented in 35.9% of the patients with paired diagnostic and relapse samples. We also found that EZH2 wild-type clones may infiltrate the bone marrow more frequently compared to the EZH2 mutant ones.

CONCLUSION

The in-depth spatio-temporal analysis identified EZH2 mutations in a considerably higher proportion of patients than previously reported. This expands the subset of FL patients who most likely would benefit from EZH2 inhibitor therapy.

CD30 expression in cutaneous B-cell lymphomas

INTRODUCTION

CD30 expression has been infrequently described in cutaneous B-cell lymphomas (CBCLs). We examined CD30 expression in reactive lymphoid hyperplasia (RLH) and CBCL and correlated expression with clinicopathologic features.

METHODS

CD30 was examined in 82 CBCL patients and 10 RLH patients that had been evaluated in our cutaneous lymphoma clinics. The CBCL patients included: primary cutaneous follicle center lymphoma (PCFCL), Grade 1/2 systemic/nodal follicular lymphoma (SFL); primary cutaneous marginal zone lymphoma/lymphoproliferative disorder (PCMZL/LPD); systemic marginal zone lymphoma (SMZL); primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT); and extracutaneous/systemic diffuse large B-cell lymphoma (eDLBCL). We scored CD30 expression for intensity and extent and related CD30 expression to age at first diagnosis, sex, site of biopsy, clinical appearance, extracutaneous involvement, multiple cutaneous lesions, B-symptoms, lymphadenopathy, positive positron emission tomography/computed tomography (PET/CT), elevated lactate dehydrogenase (LDH), and positive bone marrow biopsy.

RESULTS

CD30 expression was identified in 35% of CBCL, ranging from few, weak, scattered cells to strong and diffuse expression. It was most common in PCFCL and was not expressed in PCDLBCL-LT. Rare PCFCL expressed strong, diffuse CD30. Some cases of PCMZL/LPD, SMZL, FL, and RLH showed scattered, strongly positive cells. CD30 expression in CBCL was associated with favorable clinical features: younger age, negative PET/CT, and an LDH within normal limits.

CONCLUSIONS

CD30 may be expressed in CBCL, possibly causing diagnostic confusion. CD30 expression was most commonly identified in PCFCL and is associated with favorable clinical features. In cases with strong and diffuse expression, CD30 could be a therapeutic target.

Ki67 proliferation index in follicular lymphoma is associated with favorable outcome in patients treated with R-CHOP

Follicular lymphoma (FL) is a common, indolent small B-cell lymphoma. While the Follicular Lymphoma International Prognostic Index is widely used, reliable prognostic and predictive biomarkers are needed. A recent study suggested that architectural patterns of CD10, BCL6, and Ki67 expression may correlate with progression-free survival (PFS) in FL patients treated with chemotherapy-free regimens. We examined the prognostic and predictive utility of architectural patterns of CD10, BCL6, Ki67, and FOXP1 in 90 patients treated with immunochemotherapy (bendamustine-rituximab [BR] and R-cyclophosphamide, doxorubicin, vincristine, prednisone [CHOP]). We found that high follicular Ki67 (≥30%) was associated with longer PFS in the subgroup of patients treated with R-CHOP but not among those treated with BR. Validation of this biomarker may support routine use of Ki67 as a predictive marker in FL.

Recent advances in treatment of nodal and gastrointestinal follicular lymphoma

Follicular lymphoma (FL) is the most common low-grade lymphoma, and although nodal FL is highly responsive to treatment, the majority of patients relapse repeatedly, and the disease has been incurable with a poor prognosis. However, primary FL of the gastrointestinal tract has been increasingly detected in Japan, especially due to recent advances in small bowel endoscopy and increased opportunities for endoscopic examinations and endoscopic diagnosis. However, many cases are detected at an early stage, and the prognosis is good in many cases. In contrast, in Europe and the United States, gastrointestinal FL has long been considered to be present in 12%-24% of Stage-IV patients, and the number of advanced gastrointestinal cases is expected to increase. This editorial provides an overview of the recent therapeutic advances in nodal FL, including antibody-targeted therapy, bispecific antibody therapy, epigenetic modulation, and chimeric antigen receptor T-cell therapy, and reviews the latest therapeutic manuscripts published in the past year. Based on an understanding of the therapeutic advances in nodal FL, we also discuss future possibilities for gastroenterologists to treat gastrointestinal FL, especially in advanced cases.

Small volume biopsy diagnostic yield at initial diagnosis versus recurrence/transformation of follicular lymphoma: A retrospective Cyto-Heme Interinstitutional Collaborative study

BACKGROUND

Few studies have evaluated diagnostic yield of small volume biopsies (SVB) for the diagnosis and management of follicular lymphoma (FL).

METHODS

The authors performed a multi-institutional retrospective analysis of SVBs including fine-needle aspiration (FNA) and needle core biopsy (NCB) for initial FL diagnosis and suspected recurrence or transformation of FL. A total of 676 workups beginning with SVB were assessed for the mean number of biopsies per workup, the proportion of workups requiring multiple biopsies, and the proportion with a complete diagnosis including grade, on initial biopsy.

RESULTS

Compared to workups performed for question transformation/recurrence, those done for initial FL diagnosis were significantly more likely to require multiple biopsies (p < .01), had a higher mean number of biopsies per workup (1.7 vs. 1.1, absolute standardized difference = 1.1), and a lower complete diagnosis rate at initial biopsy (39% vs. 56%). At initial FL diagnosis, NCB +/- FNA was associated with fewer biopsies per workup compared to FNA +/- CB (1.2 vs. 1.9), fewer workups requiring multiple biopsies (23% vs. 83%), and a higher complete diagnosis rate (71% vs. 18%). In contrast, during assessment for transformation/recurrence, NCB and FNA showed a similar mean number of biopsies per workup (1.2 vs. 1.2) and few workups required multiple biopsies (6% vs. 19%).

CONCLUSIONS

SVB at initial FL diagnosis often required additional biopsies to establish a complete diagnosis. In contrast, when assessing for transformed/recurrent FL, additional biopsies were generally not obtained regardless of SVB type, suggesting that in these clinical settings SVB may be sufficient for clinical decision-making.

Study of the Utility of Myeloid Cell Nuclear Differentiation Antigen (MNDA) in the Diagnosis of Marginal Zone Lymphoma

Myeloid cell nuclear differentiation antigen (MNDA) is normally expressed on myelomonocytic cells and a subset of B lymphocytes. It was found to be differentially expressed between nodal marginal zone lymphoma (MZL) and follicular lymphoma (FL). However, MNDA has not been widely used as a diagnostic marker in clinical practice. To validate its utility, we studied the expression of MNDA by immunohistochemistry in 313 cases of small B-cell lymphomas. Our results showed that MNDA was positive in 77.9% of MZL, 21.9% of mantle cell lymphoma, 28.9% of small lymphocytic lymphoma/chronic lymphocytic leukemia, 2.6% of FL, and 25% of lymphoplasmacytic lymphoma. MNDA positivity varied from 68.0% to 84.0% among the 3 MZL subtypes, with extranodal MZL having the highest percentage. There was a statistically significant difference in MNDA expression between MZL and FL, mantle cell lymphoma, small lymphocytic lymphoma/chronic lymphocytic leukemia, or lymphoplasmacytic lymphoma. CD43 expression was slightly more frequent in MNDA-negative MZL than in MNDA-positive MZL. Combined use of CD43 and MNDA improved the diagnostic sensitivity for MZL from 77.9% to 87.8%. There was a trend of positive correlation between MNDA and p53 in MZL. In conclusion, MNDA is preferentially expressed in MZL among small B-cell lymphomas and it is a useful marker for the differentiation of MZL and FL.

Review of lymphoma in the duodenum: An update of diagnosis and management

The presentation, subtype, and macroscopic images of lymphoma vary depending on the site of the tumor within the gastrointestinal tract. We searched PubMed for publications between January 1, 2012 and October 10, 2022, and retrieved 130 articles relating to duodenal lymphoma. A further 22 articles were added based on the manual screening of relevant articles, yielding 152 articles for full-text review. The most predominant primary duodenal lymphoma was follicular lymphoma. In this review, we provide an update of the diagnosis and man-agement of representative lymphoma subtypes occurring in the duodenum: Follicular lymphoma, diffuse large B-cell lymphoma, extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue, mantle cell lymphoma, and T-cell lymphomas.

Diagnostic Discrepancies in Small-volume Biopsy for the Initial Diagnosis, Recurrence, and Transformation of Follicular Lymphoma: A Multi-Institutional Collaborative Study

Small-volume biopsies (SVBs) including fine-needle aspiration (FNA), cell block, and needle core biopsies (NCB) are increasingly utilized to diagnose and guide the clinical management of lymphoma. We established a multi-institutional interdisciplinary collaboration of cytopathologists, hematopathologists, and oncologists focused on the role of SVB in the management of patients with follicular lymphoma (FL). To assess the performance characteristics of SVB in this setting, we evaluated all consecutive SVBs performed for clinical indications of initial diagnosis, recurrence, or transformation of FL over a 5-year period and focused on the 182 that had at least one subsequent biopsy within 3 months as part of the same clinical work-up. The most common outcome of a subsequent biopsy as part of the same clinical work-up was a more specific diagnosis usually assigning the pathologic grade (111/182, 61%), followed by a complete agreement with the SVB (24/182, 13%), and change from nondiagnostic on initial biopsy to diagnostic on subsequent biopsy (21/182, 12%). A minority resulted in a diagnostic change from benign to lymphoma (17/182, 9%), a change in FL grade (5/182, 3%), or change in the lymphoma diagnostic category (4/182, 2%). There were no cases where an initial diagnosis of lymphoma was overturned. The distribution of discrepancies was similar across initial SVB types (FNA, FNA + cell block, NCB with or without FNA). Tissue limitations were noted in a minority of cases (53/182, 29%) and were enriched among initially nondiagnostic biopsies (16/21, 76%). Flow cytometry immunophenotyping was performed in the majority of cases both at the first and last biopsy (147/182, 81%). SVB can be a powerful method to detect FL in various clinical indications, with discrepant cases mostly resulting from a refinement in the initial diagnosis.

Disease-Defining Molecular Features of Primary Cutaneous B-Cell Lymphomas: Implications for Classification and Treatment

Primary cutaneous B-cell lymphoma-primary cutaneous follicle center lymphoma; primary cutaneous marginal zone lymphoma; and primary cutaneous diffuse large B-cell, leg type-is a heterogeneous group with a variety of clinical and histological presentations. Until recently, the molecular bases of these disease subtypes have been unclear. We and others have identified the specific genetic characteristics that distinguish these subtypes from their respective systemic counterparts. These molecular features can improve diagnoses, determine the likelihood of concurrent or future systemic disease, and enable the rational design of novel clinical trials.

Ovarian Follicular Lymphoma Diagnosed Due to Hydronephrosis

A 74-year-old woman presented with left lateral abdominal pain. Abdominal echography revealed left hydronephrosis and a pelvic mass. The patient underwent left adnexal resection of a suspected left ovarian tumor and was diagnosed with follicular lymphoma (FL) of clinical stage IIIA, grade 2. The patient was treated with rituximab-combined chemotherapy and achieved complete remission. The most common histological types of ovarian lymphoma are diffuse large B-cell lymphoma and Burkitt lymphoma, with FL being an extremely rare variant. We herein report a case of ovarian FL diagnosed as hydronephrosis.

[Transcriptome analysis of tissue microbiota diversity in tumor and non-tumor lymph nodes]

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.