Clinicopathological features of adult T-cell leukemia/lymphoma with T-follicular helper phenotype.

AIMS: T-follicular helper (TFH) cells are effector T-cells that are crucial for B-cell selection and differentiation. T-cell lymphomas derived from TFH cells have distinct characteristics. Additionally, in the World Health Organization (WHO) classification 5th edition, three lymphomas were introduced as independent disease entities with TFH cell origin. We aimed to investigate the clinicopathological features of adult T-cell leukemia/lymphoma (ATLL) with a TFH phenotype (TFHP). METHODS AND RESULTS: We performed TFH immunohistochemistry analysis of five biomarkers for the biopsy specimen, with TFHP being indicated by a positive result for more than two markers. Among 75 cases of ATLL, 37.3% of them showed TFHP. Compared with cases of ATLL without TFHP, cases of ATLL with TFHP showed higher C-reactive protein levels (p = 0.0219) and increased high endothelial venule proliferation (p = 0.024). However, there were no significant between-group differences in overall survival as well as other clinical and morphological findings. Furthermore, there was no significant between-group difference in TFH markers and FOXP3 expression. CONCLUSION: Some patients with ATLL may present a TFHP, which should not preclude the diagnosis of ATLL. Although presenting a TFHP does not affect prognosis, it is important to identify cases of ATLL with a TFHP since it may inform future treatment strategies.

Characteristics of chronic lymphocytic leukemia in Japan: Comprehensive analysis of the CLLRSG-01 study.

Chronic lymphocytic leukemia (CLL) is rare in Japan. We conducted the nationwide, prospective observational study CLLRSG-01 to clarify the current state of CLL in Japan and to make accurate international comparisons by preparing naturally air-dried smears like those used in other countries. Of the 201 untreated patients enrolled and evaluated, 119 were diagnosed with CLL and 82 with non-CLL mature B-cell neoplasms, based on the WHO classification. Of the 119 CLL patients, 90 were classified as typical and 29 as atypical according to FAB classification morphology, with the proportion of atypical CLL consistent with reports from other countries. Immunophenotypic analyses by flow cytometry showed that 55% of Japanese CLL patients had a Matutes score of 4 or higher, which is lower than the rate of about 90% in Europeans. Mutated IGHV was identified in 80% of Japanese CLL patients, which is a higher rate than in Western patients. The most frequent IGHV gene was VH3-30 (15%), followed by VH3-23 (12%) and VH4-34 (10%). VH1-69, the most common gene in Western countries, was identified in only one patient. These results indicate that the pattern of immunophenotypes and IGHV gene usage in Japanese CLL patients differs from that in Western patients.

EBV+ nodal T/NK-cell lymphoma associated with clonal hematopoiesis and structural variations of the viral genome.

ABSTRACT: Epstein-Barr virus (EBV)-positive (EBV+) nodal T- and natural killer (NK)-cell lymphoma is a peripheral T-cell lymphoma (EBV+ nPTCL) that presents as a primary nodal disease with T-cell phenotype and EBV-harboring tumor cells. To date, the genetic aspect of EBV+ nPTCL has not been fully investigated. In this study, whole-exome and/or whole-genome sequencing was performed on 22 cases of EBV+ nPTCL. TET2 (68%) and DNMT3A (32%) were observed to be the most frequently mutated genes whose presence was associated with poor overall survival (P = .004). The RHOA p.Gly17Val mutation was identified in 2 patients who had TET2 and/or DNMT3A mutations. In 4 patients with TET2/DNMT3A alterations, blood cell-rich tissues (the bone marrow [BM] or spleen) were available as paired normal samples. Of 4 cases, 3 had at least 1 identical TET2/DNMT3A mutation in the BM or spleen. Additionally, the whole part of the EBV genome was sequenced and structural variations (SVs) were found frequent among the EBV genomes (63%). The most frequently identified type of SV was deletion. In 1 patient, 4 pieces of human chromosome 9, including programmed death-ligand 1 gene (PD-L1) were identified to be tandemly incorporated into the EBV genome. The 3' untranslated region of PD-L1 was truncated, causing a high-level of PD-L1 protein expression. Overall, the frequent TET2 and DNMT3A mutations in EBV+ nPTCL seem to be closely associated with clonal hematopoiesis and, together with the EBV genome deletions, may contribute to the pathogenesis of this intractable lymphoma.

Multimodal Gated Mixture of Experts Using Whole Slide Image and Flow Cytometry for Multiple Instance Learning Classification of Lymphoma.

In this study, we present a deep-learning-based multimodal classification method for lymphoma diagnosis in digital pathology, which utilizes a whole slide image (WSI) as the primary image data and flow cytometry (FCM) data as auxiliary information. In pathological diagnosis of malignant lymphoma, FCM serves as valuable auxiliary information during the diagnosis process, offering useful insights into predicting the major class (superclass) of subtypes. By incorporating both images and FCM data into the classification process, we can develop a method that mimics the diagnostic process of pathologists, enhancing the explainability. In order to incorporate the hierarchical structure between superclasses and their subclasses, the proposed method utilizes a network structure that effectively combines the mixture of experts (MoE) and multiple instance learning (MIL) techniques, where MIL is widely recognized for its effectiveness in handling WSIs in digital pathology. The MoE network in the proposed method consists of a gating network for superclass classification and multiple expert networks for (sub)class classification, specialized for each superclass. To evaluate the effectiveness of our method, we conducted experiments involving a six-class classification task using 600 lymphoma cases. The proposed method achieved a classification accuracy of 72.3%, surpassing the 69.5% obtained through the straightforward combination of FCM and images, as well as the 70.2% achieved by the method using only images. Moreover, the combination of multiple weights in the MoE and MIL allows for the visualization of specific cellular and tumor regions, resulting in a highly explanatory model that cannot be attained with conventional methods. It is anticipated that by targeting a larger number of classes and increasing the number of expert networks, the proposed method could be effectively applied to the real problem of lymphoma diagnosis.

Rejuvenated iPSC-derived GD2-directed CART Cells Harbor Robust Cytotoxicity Against Small Cell Lung Cancer.

Small cell lung cancer (SCLC) is exceptionally aggressive, with limited treatment options. Disialoganglioside (GD2) is highly expressed on SCLC and is considered a good target for chimeric antigen receptor (CAR) T cells (CART). Although GD2-directed CARTs (GD2-CART) exhibit cytotoxicity against various GD2-expressing tumors, they lack significant cytotoxicity against SCLC. To enhance cytotoxicity of GD2-CARTs against SCLC, we introduced GD2-CAR into induced pluripotent stem cells (iPSC)-derived rejuvenated cytotoxic T lymphocytes (GD2-CARrejT). GD2-CARrejTs acted much more strongly against SCLC cells than did GD2-CARTs both in vitro and in vivo. Single-cell RNA sequencing elucidated that levels of expression of TIGIT were significantly lower and levels of expression of genes associated with cytotoxicity were significantly higher in GD2-CARrejTs than those in GD2-CARTs. Dual blockade of TIGIT and programmed death-1 (PD-1) increased the cytotoxicity of GD2-CARTs to some extent, suggesting that low TIGIT and PD-1 expression by GD2-CARrejTs is a major factor required for robust cytotoxicity against SCLC. Not only for robust cytotoxicity but also for availability as "off-the-shelf" T-cell therapy, iPSC-derived GD2-CARrejTs are a promising novel treatment for SCLC. SIGNIFICANCE: This research introduces iPSC-derived rejuvenated GD2-CARTs (GD2-CARrejT) as a novel approach to combat SCLC. Compared with conventional GD2-CARTs, GD2-CARrejTs with reduced TIGIT and PD-1 expression demonstrate robust cytotoxicity against SCLC and would be a promising therapy for SCLC.

Clinicopathological comparison between PTCL-TBX21 and PTCL-GATA3 in Japanese patients.

AIM: Peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) is a heterogeneous disease that can be classified into the PTCL-TBX21 and PTCL-GATA3 subtypes. METHODS: In this study, we compared the clinicopathological features of PTCL-NOS in a Japanese cohort, classified using an IHC algorithm. RESULTS: One hundred patients with PTCL-NOS were categorized as having PTCL-TBX21 (n = 55), PTCL-GATA3 (n = 24), or PTCL-unclassified (n = 21). When comparing PTCL-TBX21 and PTCL-GATA3, PTCL-TBX21 showed significantly lower CD4 positivity (p = 0.047), lower counts of high endothelial venules (p = 0.032), and a tendency for a better response to initial treatment (p = 0.088). Gene expression analysis using the nCounter system showed higher expression of tumor immunity-related genes, such as PD-L1, LAG3, and IDO1, in PTCL-TBX21 than in PTCL-GATA3. PTCL-GATA3 had significantly worse overall survival (OS) than those with PTCL-TBX21 (p = 0.047), although a similar tendency was observed for progression-free survival (PFS) (p = 0.064). PTCL-GATA3 was a prognostic factor for OS in univariate analysis (HR 2.02; 95% CI, 1.09-3.77; p = 0.027), although multivariate analysis did not show significance (HR 2.07; 95% CI, 0.93-4.61; p = 0.074). In the PFS analysis, PTCL-GATA3 was an independent prognostic factor by univariate analysis (HR 1.96; 95% CI, 1.08-3.56; p = 0.027) and multivariate analysis (HR 2.34; 95% CI, 1.07-5.11; p = 0.032). CONCLUSION: The classification of PTCL-NOS into PTCL-TBX21 and PTCL-GATA3 is useful for predicting the prognosis of Japanese patients and stratifying the administration of tumor immune checkpoint inhibitors in clinical practice.

Secondary central nervous system involvement in patients with diffuse large B-cell lymphoma treated with rituximab combined CHOP therapy - a supplementary analysis of JCOG0601.

Secondary central nervous system involvement (sCNSi) in diffuse large B-cell lymphoma (DLBCL) is fatal. However, its features in patients with sCNSi who are categorized as lower risk by international prognostic index (IPI) or CNS-IPI are not yet fully understood. In the present analysis, we evaluated DLBCL patients who developed sCNSi at their first progression and who participated in JCOG0601, most of whom were lower risk by IPI. Of 409 patients, 21 (5.1%) developed sCNSi during a median follow-up of 4.9 years. Five-year cumulative incidence of sCNSi were 5.1%; and 4.0%, 5.3%, and 11.5% at low, intermediate, and high risk of CNS-IPI, respectively. The most common locations of extranodal lesions at the time of registration in patients with sCNSi were the stomach (n = 4), paranasal cavity (n = 3), and bone marrow (n = 2). In univariable analysis, paranasal cavity lesion was a high-risk factor for sCNSi (subdistribution hazard ratio, 4.34 [95% confidence interval 1.28-14.73]). Median overall survival after sCNSi was 1.3 years, with a 2-year overall survival rate of 39.3%. The incidence of sCNSi in DLBCL patients at lower risk of CNS-IPI was low, as previously reported, but paranasal cavity lesion might indicate high risk for organ involvement. CLINICAL TRIAL REGISTRATION: JCOG0601 was registered in the UMIN Clinical Trials Registry (UMIN000000929, date of registration; December 04, 2007) and the Japan Registry of Clinical Trials (jRCTs031180139, date of registration; February 20, 2019).

Primary renal peripheral T-cell lymphoma, not otherwise specified, treated with partial nephrectomy.

Introduction: Renal involvement by non-Hodgkin's lymphoma is very rare, and the kidney as the primary site of this lymphoma is much more uncommon. We report a case of primary renal peripheral T-cell lymphoma, not otherwise specified, treated with partial nephrectomy. Case presentation: A 63-year-old man was hospitalized with coronavirus infectious disease, emerged in 2019 in the emergency department. Computed tomography examination showed a 2-cm renal mass in the right kidney. Abdominal enhanced computed tomography examination revealed that the noted mass showed good enhancement in the corticomedullary phase and washout in the nephrogenic phase. No metastatic lesions were found. He was diagnosed as having cT1aN0M0 renal cell carcinoma, and robotic-assisted partial nephrectomy was carried out. The pathological diagnosis was peripheral T-cell lymphoma, not otherwise specified. He has been followed for 20 months after robotic-assisted partial nephrectomy without additional treatment and recurrence. Conclusion: We experienced a primary renal peripheral T-cell lymphoma, not otherwise specified that was followed up without treatment after surgery.

Co-expression of regulatory B-cell markers, transforming growth factor ß and interleukin-10 as a prognostic factor in diffuse large B-cell lymphoma.

Regulatory B cells (Bregs) suppress antitumor immunity by producing anti-inflammatory cytokines such as transforming growth factor ß (TGF-ß) and interleukin-10 (IL-10) and promoting tumor growth. It is unknown whether diffuse large B-cell lymphoma (DLBCL), a common subtype of B-cell malignancy, exhibits characteristics similar to those of Bregs. This study aimed to clarify the features of DLBCLs carrying Breg markers. In 123 DLBCL cases, we evaluated TGF-ß and IL-10 expression in tumor biopsy samples using immunohistochemical staining and retrospectively analyzed their clinicopathological characteristics. Fifteen cases (12.2 %) classified as Breg-type DLBCL were positive for both TGF-ß and IL-10. Breg-type DLBCL is mainly classified as having activated B cell-like cells of origin. Breg-type DLBCL cases showed significantly worse progression-free survival and overall survival (OS) than other DLBCL cases (P = 0.0016 and P = 0.042, respectively). In multivariate analysis, Breg-type DLBCL significantly affected OS (hazard ratio, 3.13; 95 % confidence interval 1.15-8.55; P = 0.025). Gene expression analysis showed that the expression of follicular dendritic cell-associated genes (FCER2, PIK3CD, FOXO1) was downregulated in Breg-type DLBCLs compared to other DLBCLs. These results suggest that the double expression of Breg markers, TGF-ß and IL-10, in tumor cells indicates a poor prognosis in DLBCL patients. Further studies evaluating genomic abnormalities could confirm the characteristics of Breg-type DLBCL.

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.

Increased expression of leucine-rich α-2 glycoprotein 1 as a predictive biomarker of favorable progression-free survival in meningioma.

Most meningiomas, which are frequent central nervous system tumors, are classified as World Health Organization (WHO) grade 1 because of their slow-growing nature. However, the recurrence rate varies and is difficult to predict using conventional histopathological diagnoses. Leucine-rich α-2 glycoprotein 1 (LRG1) is involved in cell signal transduction, cell adhesion, and DNA repair and is a predictive biomarker in different malignant tumors; however, such a relationship has not been reported in meningiomas. We examined tissue microarrays of histological samples from 117 patients with grade 1 and 2 meningiomas and assessed their clinical and pathological features, including expression of LRG1 protein. LRG1-high meningiomas showed an increased number of vessels with CD3-positive cell infiltration (P = 0.0328) as well as higher CD105-positive vessels (P = 0.0084), as compared to LRG1-low cases. They also demonstrated better progression-free survival (hazard ratio [HR] 0.11, 95% confidence interval [CI] 0.016-0.841) compared to LRG1-low patients (P = 0.033). Moreover, multivariate analysis indicated that high LRG1 expression was an independent prognostic factor (HR, 0.13; 95% CI, 0.018-0.991; P = 0.049). LRG1 immunohistochemistry may be a convenient tool for estimating the prognosis of meningiomas in routine practice. Further studies are required to elucidate the key role of LRG1 in meningioma progression.

Clinicopathological analysis of CD47 and signal regulatory protein alpha expression in myeloid sarcoma patients: CD47 expression is a favourable prognostic factor.

Myeloid sarcoma is a rare extramedullary haematopoietic malignancy. Interaction between CD47 and signal regulatory protein α (SIRPα) inhibits phagocytosis. CD47-positive tumours confer poor prognoses in various malignant tumours, including acute myeloid leukaemia. This study aimed to investigate the clinicopathological effects of CD47 and SIRPα expression in myeloid sarcoma. Immunohistochemistry (IHC) of CD47 and SIRPα was performed in 84 biopsy samples obtained from patients with myeloid sarcoma, some of which were CD47-positive. Patients were categorised into the following two groups based on IHC of SIRPα: those with SIRPα-positive neoplastic cells (nSIRPα) and, SIRPα expression on non-neoplastic stromal cells in tumour microenvironment (miSIRPα). In addition, patients with CD47 positivity had higher lymphocytic infiltration into the tumour microenvironment. Overall, these patients had significantly higher overall survival, however, no significant difference was observed in progression-free survival. No significant prognostic differences were observed between the nSIRPα and miSIRPα groups. This is the first study to demonstrate an association between CD47 expression and improved prognosis in myeloid sarcoma. Nonetheless, it will be necessary to conduct additional research on gene expression and genomic abnormalities to elucidate the corresponding pathogenesis of myeloid sarcoma.

iPSC-derived hypoimmunogenic tissue resident memory T cells mediate robust anti-tumor activity against cervical cancer.

Functionally rejuvenated human papilloma virus-specific cytotoxic T lymphocytes (HPV-rejTs) generated from induced pluripotent stem cells robustly suppress cervical cancer. However, autologous rejT generation is time consuming, leading to difficulty in treating patients with advanced cancer. Although use of allogeneic HPV-rejTs can obviate this, the major obstacle is rejection by the patient immune system. To overcome this, we develop HLA-A24&-E dual integrated HPV-rejTs after erasing HLA class I antigens. These rejTs effectively suppress recipient immune rejection while maintaining more robust cytotoxicity than original cytotoxic T lymphocytes. Single-cell RNA sequencing performed to gain deeper insights reveal that HPV-rejTs are highly enriched with tissue resident memory T cells, which enhance cytotoxicity against cervical cancer through TGFßR signaling, with increased CD103 expression. Genes associated with the immunological synapse also are upregulated, suggesting that these features promote stronger activation of T cell receptor (TCR) and increased TCR-mediated target cell death. We believe that our work will contribute to feasible "off-the-shelf" T cell therapy with robust anti-cervical cancer effects.

Angioimmunoblastic T-Cell Lymphoma after Treatment of Classic Hodgkin Lymphoma: A Case Report.

We report a case of a 24-year-old man who developed angioimmunoblastic T-cell lymphoma (AITL) after treatment for refractory lymphocyte-rich classic Hodgkin lymphoma (LR-CHL). This patient was treated with the BV+AVD (brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine) protocol for LR-CHL but progressed before completing chemotherapy. The pathological imaging showed the typical findings of LR-CHL at the first onset and first progression. Rescue chemotherapy and high-dose chemotherapy combined with autologous hematopoietic stem cell transplantation (AHSCT) were performed for refractory LR-CHL, and complete remission was achieved. However, the recurrence was suspected 6 months after AHSCT. The pathological findings of the lymph node biopsy at this time were different from those of the previous two lymph node biopsies, demonstrating findings of AITL. The finding of the immunohistochemical staining and polymerase chain reaction results supported the diagnosis. Although it has been reported that the risk for the development of non-Hodgkin lymphoma after treatment for Hodgkin lymphoma is increased, most are B-cell lymphomas, and few cases of AITL have been reported. AITL is a type of peripheral T-cell lymphoma that generally occurs in middle-aged and elderly people and that rarely occurs in young people. Here, we were able to make an accurate diagnosis by performing re-examination even when recurrence of LR-CHL was suspected. As there are no detailed case reports of AITL developing into secondary non-Hodgkin lymphoma, here we report on an identified case.

Updated guidelines for chronic active Epstein-Barr virus disease.

Chronic active Epstein-Barr virus disease (CAEBV), formerly named chronic active Epstein-Barr virus infection, is characterized by systemic inflammation and clonal proliferation of Epstein-Barr virus (EBV)-infected T or NK cells. As CAEBV is a potentially life-threatening illness, appropriate diagnosis and therapeutic interventions are necessary for favorable clinical outcomes. Substantial evidence regarding the pathogenesis and treatment of CAEBV has been accumulated since previous guidelines for the diagnosis of CAEBV were proposed. To reflect this evidence, we updated the guidelines for the diagnosis and treatment of CAEBV to improve clinical management of the disease. The details of the updated guidelines are presented in this report. Diagnosis of CAEBV now requires confirmation of a high copy number of EBV genome and EBV-infected T or NK cells. An EBV DNA load ≥ 10,000 IU/mL in whole blood is proposed as the diagnostic cutoff value for CAEBV in this updated guideline. A standard treatment approach for CAEBV has not been established, and hematopoietic stem cell transplantation (HSCT) is considered the only curative treatment. Chemotherapy can be administered to control disease activity before HSCT.

Intratumoral thrombosis as a histological biomarker for predicting epidermal growth factor receptor alteration and poor prognosis in patients with glioblastomas.

PURPOSE: Intratumoral thrombosis is a specific finding in glioblastomas and considered the origin of palisading necrosis. Its distribution and contribution to the glioblastoma pathophysiology and systemic thrombosis are obscure, although deep vein thrombosis is a common complication in glioblastoma cases. METHODS: Clinicopathological and genetic analyses were performed on 97 glioblastoma tissue specimens to elucidate the role of thrombotic events and associated molecular abnormalities. RESULTS: Morphologically, intratumoral thrombosis was observed more frequently in vessels composed of single-layered CD34-positive endothelium and/or αSMA-positive pericytes in the tumor periphery, compared to microvascular proliferation with multi-channeled and pericyte-proliferating vessels in the tumor center. Intratumoral thrombosis was significantly correlated with the female sex, high preoperative D-dimer levels, and epidermal growth factor receptor (EGFR) amplification. The presence of one or more thrombi in 20 high-power fields was a predictive marker of EGFR amplification, with a sensitivity of 81.5% and specificity of 52.6%. RNA sequencing demonstrated that the group with many thrombi had higher EGFR gene expression levels than the group with few thrombi. The tumor cells invading along the vessels in the tumor periphery were positive for wild-type EGFR but negative for EGFRvIII, whereas the cells around the microvascular proliferation (MVP) in the tumor center were positive for both wild-type EGFR and EGFRvIII. Intratumoral thrombosis is an independent poor prognostic factor. CONCLUSIONS: Aberrant but exquisitely regulated EGFR can induce thrombosis in non-MVP vessels in the tumor invasion area and then promote palisading necrosis, followed by hypoxia, abnormal angiogenesis, and further tumor cell invasion.

Digital spatial profiling of CD4+ T cells in classic Hodgkin lymphoma.

Classic Hodgkin lymphoma (CHL) harbors a small number of Hodgkin-Reed-Sternberg (HRS) cells scattered among numerous lymphocytes. HRS cells are surrounded by distinct CD4+ T cells in a rosette-like manner. These CD4+ T cell rosettes play an important role in the tumor microenvironment (TME) of CHL. To elucidate the interaction between HRS cells and CD4+ T cell rosettes, we completed digital spatial profiling to compare the gene expression profiles of CD4+ T cell rosettes and other CD4+ T cells separated from the HRS cells. Immune checkpoint molecules including OX40, programed cell death-1 (PD-1), and cytotoxic T lymphocyte associated protein 4 (CTLA-4) expression was higher in CD4+ T cell rosettes compared to other CD4+ T cells. Immunohistochemistry confirmed variable PD-1, CTLA-4, and OX40 expression in the CD4+ T cell rosettes. This study introduced a new pathological approach to study the CHL TME, and provided deeper insight into CD4+ T cells in CHL.