Analysis of Notch1 protein expression in methotrexate-associated lymphoproliferative disorders.

Methotrexate (MTX)-associated lymphoproliferative disorder (MTX-LPD) is a lymphoproliferative disorder in patients treated with MTX. The mechanism of pathogenesis is still elusive, but it is thought to be a complex interplay of factors, such as underlying autoimmune disease activity, MTX use, Epstein-Barr virus infection, and aging. The NOTCH genes encode receptors for a signaling pathway that regulates various fundamental cellular processes, such as proliferation and differentiation during embryonic development. Mutations of NOTCH1 have been reported in B-cell tumors, including chronic lymphocytic leukemia/lymphoma, mantle cell lymphoma, and diffuse large B-cell lymphoma (DLBCL). Recently, it has also been reported that NOTCH1 mutations are found in post-transplant lymphoproliferative disorders, and in CD20-positive cells in angioimmunoblastic T-cell lymphoma, which might be associated with lymphomagenesis in immunodeficiency. In this study, to investigate the association of NOTCH1 in the pathogenesis of MTX-LPD, we evaluated protein expression of Notch1 in nuclei immunohistochemically in MTX-LPD cases [histologically DLBCL-type (n = 24) and classical Hodgkin lymphoma (CHL)-type (n = 24)] and de novo lymphoma cases [DLBCL (n = 19) and CHL (n = 15)]. The results showed that among MTX-LPD cases, the expression of Notch1 protein was significantly higher in the DLBCL type than in the CHL type (P < 0.001). In addition, among DLBCL morphology cases, expression of Notch1 tended to be higher in MTX-LPD than in the de novo group; however this difference was not significant (P = 0.0605). The results showed that NOTCH1 may be involved in the proliferation and tumorigenesis of B cells under the use of MTX. Further research, including genetic studies, is necessary.

Sutimlimab suppresses SARS-CoV-2 mRNA vaccine-induced hemolytic crisis in a patient with cold agglutinin disease.

Cold agglutinin disease (CAD) is a rare form of acquired autoimmune hemolytic anemia driven mainly by antibodies that activate the classical complement pathway. Several patients with CAD experience its development or exacerbation of hemolysis after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or after receiving the SARS-CoV-2 mRNA vaccine. Therefore, these patients cannot receive an additional SARS-CoV-2 mRNA vaccination and have a higher risk of severe SARS-CoV-2 infection. Sutimlimab is a monoclonal antibody that inhibits the classical complement pathway of the C1s protein and shows rapid and sustained inhibition of hemolysis in patients with CAD. However, whether sutimlimab could also inhibit hemolysis caused by SARS-CoV-2 mRNA vaccination is uncertain. Here, we present the case of a 70-year-old man with CAD who repeatedly experienced a hemolytic crisis after receiving SARS-CoV-2 mRNA vaccines. The patient eventually underwent SARS-CoV-2 mRNA vaccination safely, without hemolytic attack, under classical pathway inhibition therapy with sutimlimab. This report suggests that appropriate sutimlimab administration can suppress SARS-CoV-2 mRNA vaccination-induced CAD exacerbation, and that it could be a preventive strategy to minimize hemolytic attacks in susceptible populations.

Distribution and clinical impact of molecular subtypes with dark zone signature of DLBCL in a Japanese real-world study.

The distribution and clinical impact of cell-of-origin (COO) subtypes of diffuse large B-cell lymphoma (DLBCL) outside Western countries remain unknown. Recent literature also suggests that there is an additional COO subtype associated with the germinal center dark zone (DZ) that warrants wider validation to generalize clinical relevance. Here, we assembled a cohort of Japanese patients with untreated DLBCL and determined the refined COO subtypes, which include the DZ signature (DZsig), using the NanoString DLBCL90 assay. To compare the distribution and clinical characteristics of the molecular subtypes, we used a data set from the cohort of British Columbia Cancer (BCC) (n = 804). Through the 1050 patient samples on which DLBCL90 assay was successfully performed in our cohort, 35%, 45%, and 6% of patients were identified to have germinal center B-cell-like (GCB) DLBCL, activated B-cell-like (ABC) DLBCL, and DZsig-positive (DZsigpos) DLBCL, respectively, with the highest prevalence of ABC-DLBCL, differing significantly from the BCC result (P < .001). GCB-DLBCL, ABC-DLBCL, and DZsigpos-DLBCL were associated with 2-year overall survival rates of 88%, 75%, and 66%, respectively (P < .0001), with patients with DZsigpos-DLBCL having the poorest prognosis. In contrast, GCB-DLBCL without DZsig showed excellent outcomes after rituximab-containing immunochemotherapy. DZsigpos-DLBCL was associated with the significant enrichment of tumors with CD10 expression, concurrent MYC/BCL2 expression, and depletion of microenvironmental components (all, P < .05). These results provide evidence of the distinct distribution of clinically relevant molecular subtypes in Japanese DLBCL and that refined COO, as measured by the DLBCL90 assay, is a robust prognostic biomarker that is consistent across geographical areas.

Expression and clinicopathological characteristics of PDX1, PTF1A, and SALL4 in large and small ducts of ectopic pancreas located in gastro-duodenum and jejunum.

An ectopic pancreas is defined as pancreatic tissue outside its normal location, anatomically separated from the pancreas. The transcription factor pancreas/duodenum homeobox protein 1 (PDX1) is involved in maintaining the pancreas and functions in early pancreatic development, beta cell differentiation, and endocrine non beta cells. Pancreatic transcription factor 1 subunit alpha (PTF1A) affects exocrine cell formation and regulation of acinar cell identity, and is expressed in exocrine cells as a transcription factor. The depletion of SALL4 disrupts self-renewal and induces differentiation. To clarify which of PDX1, PTF1A, or SALL4 determines the difference in Heinrich's classification, we examined the localization and number of positive cells. We analyzed the differential expression of PDX1, PTF1A, and SALL4 in large and small ducts in ectopic pancreas by immunohistochemistry. Results showed that the number of PTF1A-positive cells in large ducts was more widespread in type I than in type II in the gastro-duodenum, and more SALL4-positive cells were noticed in large ducts than in small ducts in the gastro-duodenum of type II. Our results revealed that PTF1A might promote exocrine differentiation in developing the pancreatic tissues, and that those with widespread expression differentiate into exocrine cells.

Regression of Mucosa-Associated Lymphoid Tissue Lymphoma Arising From the Nonampullary Descending Part of the Duodenum by Treatment With Antibiotics in a Helicobacter pylori-Negative Patient.

We report a 63-year-old male, Helicobacter pylori-negative patient with mucosa-associated lymphoid tissue (MALT) lymphoma of the second part of the duodenum that regressed after antibiotic treatment. Esophagogastroduodenoscopy (EGD) showed flat elevation with shallow depression on the contralateral side of the ampulla of Vater. The lesion was limited to the duodenal second part. The patient had a history of Helicobacter pylori positivity, with successful eradication at 41 years of age. Twelve months after vonoprazan (VPZ)-based antibiotic treatment, the duodenal lesion had obviously regressed, and the pathological diagnosis was complete histological response (ChR). This case suggests that certain bacteria may promote the development of duodenal MALT lymphoma.

Benefit of prednisolone alone in nodal peripheral T-cell lymphoma with T follicular helper phenotype.

A 71-year-old Japanese man presented with severe thrombocytopenia. A whole-body CT at presentation showed small cervical, axillary, and para-aortic lymphadenopathy, leading to suspicion of immune thrombocytopenia due to lymphoma. Biopsy was difficult to perform because of severe thrombocytopenia. Thus, he received prednisolone (PSL) therapy and his platelet count gradually recovered. Two and a half years after PSL therapy initiation, his cervical lymphadenopathy slightly progressed without other clinical symptoms. Hence, a biopsy from the left cervical lymph node was performed, and he was diagnosed with nodal peripheral T-cell lymphoma (PTCL) with T follicular helper (TFH) phenotype. Due to various complications, we continued treatment with prednisolone alone after the diagnosis of lymphoma; however, there was no further increase in lymph node enlargement and no other lymphoma-related symptoms for one and a half years after diagnosis. Although immunosuppressive therapy has been reported to produce a response in some patients with angioimmunoblastic T-cell lymphoma, our experience suggests that a similar subset may exist in patients with nodal PTCL with TFH phenotype, which has the same cellular origin. Immunosuppressive therapies may constitute an alternative treatment option even in the era of novel molecular-targeted therapies, especially for elderly patients who are ineligible for chemotherapy.

Bone marrow microenvironment disruption and sustained inflammation with prolonged haematologic toxicity after CAR T-cell therapy.

Mechanisms of prolonged cytopenia (PC) after chimeric antigen receptor (CAR) T-cell therapy, an emerging therapy for relapsed or refractory diffuse large B-cell lymphoma, remain elusive. Haematopoiesis is tightly regulated by the bone marrow (BM) microenvironment, called the 'niche'. To investigate whether alterations in the BM niche cells are associated with PC, we analysed CD271+ stromal cells in BM biopsy specimens and the cytokine profiles of the BM and serum obtained before and on day 28 after CAR T-cell infusion. Imaging analyses of the BM biopsy specimens revealed that CD271+ niche cells were severely impaired after CAR T-cell infusion in patients with PC. Cytokine analyses after CAR T-cell infusion showed that CXC chemokine ligand 12 and stem cell factor, niche factors essential for haematopoietic recovery, were significantly decreased in the BM of patients with PC, suggesting reduced niche cell function. The levels of inflammation-related cytokines on day 28 after CAR T-cell infusion were consistently high in the BM of patients with PC. Thus, we demonstrate for the first time that BM niche disruption and sustained elevation of inflammation-related cytokines in the BM following CAR T-cell infusion are associated with subsequent PC.

Comparison of serum sIL-2R and LDH levels in patients with intravascular large B-cell lymphoma and patients with advanced stage diffuse large B-cell lymphoma.

Intravascular large B-cell lymphoma (IVL) is a rare type of lymphoma characterized by tumor growth selectively within the vessels. The 5th edition of the World Health Organization classification defines IVL as a large B-cell lymphoma, the same as diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS). Since the clinical manifestations of IVL are nonspecific, the diagnosis is time-consuming, and the course is often fatal. Serum soluble interleukin-2 receptor (sIL-2R) and serum lactate dehydrogenase (LDH) levels are known to be elevated in a variety of lymphomas. However, the mechanism of sIL-2R elevation in B-cell lymphomas is not fully understood. In this study, we analyzed the serum level of laboratory findings, including sIL-2R and LDH, as well as the presence of B symptoms in 39 patients with IVL, and compared them with 56 patients with stage IV DLBCL. Both sIL-2R and LDH levels were significantly higher in IVL than in DLBCL (p = 0.035 and p = 0.002, respectively). In IVL, there were no significant differences in both sIL-2R and LDH levels between patients with and without B symptoms (p = 0.206 and p = 0.441, respectively). However, in DLBCL, both sIL-2R and LDH levels were significantly higher in the presence of B symptoms (p = 0.001 and p < 0.001, respectively). The high sIL-2R and LDH levels in IVL may be related to the peripheral blood microenvironment, but further studies are needed to verify this.

Effect of a Cyclooxygenase-2 Inhibitor in Combination with (-)-Epigallocatechin Gallate or Polyphenon E on Cisplatin-Induced Lung Tumorigenesis in A/J Mice.

We investigated the effects of celecoxib combined with (-)-epigallocatechin-3-gallate (EGCG) or polyphenon E in a cisplatin-induced lung tumorigenesis model. Four-week-old female A/J mice were divided into seven groups: (i) Control, (ii) 150 mg/kg celecoxib (150Cel), (iii) 1,500 mg/kg celecoxib (1500Cel), (iv) EGCG+150 mg/kg celecoxib (EGCG+150Cel), (v) EGCG+1,500 mg/kg celecoxib (EGCG+1500Cel), (vi) polyphenon E+150 mg/kg celecoxib (PolyE+150Cel), and (vii) polyphenon E+1,500 mg/kg celecoxib (PolyE+1500Cel). All mice were administered cisplatin (1.62 mg/kg of body weight, i.p.) 1×/week for 10 weeks and sacrificed at week 30; the numbers of tumors on the lung surface were then determined. The tumor incidence and multiplicity (no. of tumors/mouse, mean±SD) were respectively 95% and 2.15±1.50 in Control, 95% and 2.10±1.29 in 150Cel, 86% and 1.67±1.20 in 1500Cel, 71% and 1.38±1.24 in EGCG+150Cel, 67% and 1.29±1.38 in EGCG+1500Cel, 80% and 1.95±1.36 in PolyE+150Cel, and 65% and 1.05±0.10 in PolyE+1500Cel. The combination of high-dose celecoxib with EGCG or polyphenon E significantly reduced multiplicity in cisplatin-induced lung tumors.

High-grade Endometrial Carcinoma With a Hepatoid Carcinoma-like Component.

Endometrial carcinoma with hepatoid differentiation is rare and <20 reported cases have been reported as endometrial hepatoid carcinoma (EHC). We present a case of EHC associated with serous carcinoma in a 76-yr-old Japanese woman. The hepatoid component showed trabecular, pseudoglandular, and diffuse proliferation of hepatoid cells. The hepatoid cells were positive for α-fetoprotein, Hep-Per-1, glypican 3, and HNF-1ß, weakly and focally positive for SALL4, and negative for PAX8. Both of the serous and hepatoid components showed overexpression of p53. The serum α-fetoprotein on postoperative day 5 was 3691 ng/mL. The postoperative course has remained uneventful for 4 yr. These findings suggested that EHC developed from serous carcinoma by acquiring hepatocytic features and losing Müllerian features. Both serous and hepatoid components showed p53 overexpression, suggesting they share a TP53 mutation as a common primary driver.

Follicular lymphoma and marginal zone lymphoma: how many diseases?

Follicular lymphoma (FL) and marginal zone lymphoma (MZL) are indolent mature B-cell neoplasms with variable clinical presentation and distinct histopathologic features. Recent advances in the biology and molecular characteristics of these lymphomas have further expanded our understanding of the heterogeneous nature of these lymphomas, with increasing recognition of specific disease entities within the broader categories of FL and MZL. Here, we discuss the conclusions of the 2022 International Consensus Classification of Mature Lymphoid Neoplasms (2022 ICC) dealing with FL, and review differences with the proposed WHO 5th Edition classification. We review issues related to grading and alternative forms of FL especially those lacking the genetic hallmark of FL, the t(14;18) chromosomal alteration. Among them, t(14;18)-negative CD23+ follicle center lymphoma has been proposed by the 2022 ICC as a provisional entity. Other follicle center-derived lymphomas such as pediatric-type follicular lymphoma, testicular follicular lymphoma, primary cutaneous follicle center lymphoma, and large B-cell lymphoma with IRF4 rearrangement are considered distinct entities separate from conventional FL. Importantly, large B-cell lymphoma with IRF4 rearrangement introduced as a provisional entity in the WHO 2017 is upgraded to a definite entity in the 2022 ICC. We also discuss diagnostic strategies for recognition of MZLs including splenic MZL, extranodal MZL (MALT lymphoma), and primary nodal MZL. The importance of molecular studies in the distinction among marginal zone lymphoma subtypes is emphasized, as well as their value in the differential diagnosis with other B-cell lymphomas.

An unusual case of hepatosplenic T-cell lymphoma-like unclassifiable T/NK-cell lymphoma accompanied by acute myeloid leukemia.

We describe a case of unclassifiable T/NK-cell lymphoma with concomitant acute myeloid leukemia (AML). A 73-year-old Japanese man was diagnosed with AML by bone marrow smear, but the presence of splenomegaly and liver tumor was incompatible with AML. Splenectomy and hepatic resection were performed to resolve the thrombocytopenia and define the diagnosis. The pathological findings showed sinusoidal involvement of abnormal lymphoid cells that were CD3-positive but negative for T-cell receptor (TCR) rearrangement. Our case could not be categorized as hepatosplenic T-cell lymphoma because of the lack of immunohistological expression of TCR, despite the clinical similarity.

Immunohistochemistry for IRTA1 and MNDA helps differentiate gastric MALT lymphoma from chronic gastritis/reactive lymphocyte hyperplasia.

It is difficult to histologically differentiate extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) from chronic gastritis (CG)/ reactive lymphoid hyperplasia (RLH). To determine whether immunohistochemistry for IRTA1 and MNDA can differentiate gastric MALT lymphoma from CG/RLH, we investigated 81 stomach biopsy specimens [Wotherspoon grade (WG) 1, 11 cases; WG 2, 9 cases; WG 3, 20 cases; WG 4, 31 cases; and WG 5, 10 cases]. According to a previously reported algorithm involving PCR for immunoglobulin heavy (IgH) chain locus rearrangement, all 81 cases were divided into three groups: CG/RLH (55 cases), MALT lymphoma (19 cases) groups, and IgH undetectable group (7 cases). We analyzed the CG/RLH and MALT lymphoma groups. The median percentage of IRTA1-positive cells was 0% (range 0%-90.6%) in the CG/RLH group and 43.5% (range 0%-97.6%) in the MALT lymphoma group (p < 0.0001). The median percentage of MNDA-positive cells was 32.4% (range 0%-97.6%) in the CG/RLH group and 55.1% (range 0%-97.6%) in the MALT lymphoma group (p = 0.0044). These results indicate that immunohistochemistry for IRTA1 and MNDA can help differentiate gastric MALT lymphoma from CG/RLH.

A Case Report on Apocrine Encapsulated Papillary Carcinoma of the Breast with Frank Invasion: A Diagnostic Quandary.

Encapsulated papillary carcinoma is a special type of breast cancer defined in the fifth edition of the World Health Organization breast tumor classification guidelines. Apocrine encapsulated papillary carcinoma is extremely rare, and only 10 cases have been described previously. We encountered a case of apocrine encapsulated papillary carcinoma with frank invasion. The patient was a 77-year-old woman with a painless mass in her right breast. Core needle biopsy revealed that the tumor cells had voluminous eosinophilic cytoplasm and enlarged nuclei with prominent nucleoli. We diagnosed this lesion as carcinoma with apocrine differentiation and suggested the possibility of an encapsulated papillary carcinoma. The patient underwent a right-sided mastectomy. Gross examination of the resected specimen revealed a multilobulated tumor. Microscopically, the tumor cells, which had voluminous eosinophilic cytoplasm and enlarged nuclei with prominent nucleoli, proliferated in papillary fashion with fibrous stalks in the cystic space. Myoepithelial cells were not observed around the cystic space. Frank invasion was also observed around the encapsulated papillary carcinoma. Immunohistochemistry analysis revealed that the tumor cells were negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 and positive for androgen receptor and gross cys-tic disease fluid protein 15. Based on these findings, we diagnosed this lesion as an apocrine encapsulated papillary carcinoma with frank invasion.

Historical and pathological overview of Castleman disease.

Castleman disease consists of several lymphoproliferative subtypes that share some histological features in the lymph nodes. On the other hand, numerous clinical findings and etiologies make the disease challenging to understand. The origin of the disease is the hyaline vascular-type unicentric Castleman disease (UCD), first reported by Benjamin Castleman et al. in 1954. Although UCD is characterized by localized lesions and lack of symptoms, multicentric Castleman disease (MCD) with multiple lesions and systemic symptoms was reported by Frizzera in 1983. MCD is further divided according to KSHV/HHV8 infection status. In KSHV/HHV8-related MCD, viral infection signals lead to excessive cytokine production, and cause clinical and pathologic abnormalities. Some cases of plasma cell-type KSHV/HHV8-negative MCD can be found in association with POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, M-proteins, and skin changes), which is a paraneoplastic syndrome. The others are idiopathic MCD, which are currently considered a heterogeneous group of diseases with overlapping pathological and clinical features. In this article, we summarize the historical evolution of Castleman disease to help understand the disease concept. We also review the latest ideas and definitions of the subtypes within the MCD spectrum and summarize the histopathological findings.

Systemic Abscopal Effect of Low-dose Radiotherapy (2 Gy ×2) against Palatine Tonsil Follicular Lymphoma.

A 52-year-old man presented with palatine tonsillar swelling caused by follicular lymphoma. His tumor burden was low, but exacerbation of snoring and dysphagia was observed. Considering the first wave of coronavirus disease 2019 (COVID-19) pandemic, he received palliative 4-Gy irradiation to the tonsils in 2 fractions, which induced partial regression of tonsillar swellings and eradication of the circulating lymphoma cells. We suggest that low-dose radiotherapy triggered an abscopal effect of lymphoma, which allowed the patient time to receive COVID-19 vaccination before starting immunosuppressive chemo-immunotherapy.

Microsatellite Instability Analysis and Its Prognostic Value in Invasive Nonampullary Duodenal Adenocarcinoma.

PURPOSE: Nonampullary duodenal adenocarcinoma (NADA) is a rare disease. Although several prognostic factors have been reported for this disease, they remain controversial due to their rarity. In this study, we retrospectively analyzed 54 cases of invasive NADA, focusing on the microsatellite instability (MSI) phenotype, programmed cell death-ligand 1 (PD-L1) expression, and prognostic factors. METHODS: Expression of the PD-L1 protein and cell differentiation markers in tumors was detected by immunohistochemistry. Microsatellite markers (NR-21, NR-22, NR-24, BAT-25, and BAT-26) were amplified for MSI assessment by PCR. RESULTS: The incidence of MSI in invasive NADA was 35.2%. No significant correlation between the MSI phenotype and clinicopathological factors was observed. Positive expression of PD-L1 by immune cells was common in advanced-stage disease (p = 0.054), and positive expression of PD-L1 in cancer cells correlated significantly with the histologically undifferentiated type (p = 0.016). Kaplan-Meier survival analysis demonstrated a significantly better overall survival (OS) in patients with MSI (p = 0.013) and at early-stage disease (p = 0.000) than in those with microsatellite-stable or at late tumor stages. Univariate and multivariate analyses showed that MSI (hazard ratio [HR]: 0.282, 95% confidence interval [CI]: 0.106-0.751, p = 0.011) and early tumor stage (stage I-II) (HR: 8.81, 95% CI: 2.545-30.500, p = 0.001) were independent better prognostic factors of OS. CONCLUSIONS: MSI and early tumor stage (stage I-II) were independent better prognostic factors of OS. A high proportion of MSI phenotypes and positive PD-L1 expression may be helpful for identifying immune checkpoint inhibitors as a novel therapeutic strategy.

Angioimmunoblastic T-cell Lymphoma Presenting as a Methotrexate-associated Lymphoproliferative Disorder with Extreme Peripheral Blood Plasmacytosis.

A 74-year-old man was admitted to our hospital because of systemic lymphadenopathy, weight loss, and a fever at night that had persisted for approximately 1 month. Blood tests revealed extreme peripheral blood plasmacytosis and hypergammaglobulinemia. A lymph node biopsy showed angioimmunoblastic T-cell lymphoma (AITL). Based on the history of methotrexate (MTX) administration, the established diagnosis was MTX-associated lymphoproliferative disorder (MTX-LPD). After MTX was discontinued, the lymphadenopathy spontaneously regressed and the plasmacytosis disappeared. He had no disease progression for three years. We found that AITL as an MTX-LPD can cause plasmacytosis, and the prognosis of this disease may not be poor.

Chronic active Epstein-Barr virus infection presenting as refractory chronic sinusitis.

A 44-year-old Japanese man presented with fever and sore throat. He had a history of refractory chronic sinusitis that did not respond to several years of pharmacotherapy, and underwent endoscopic sinus surgery (ESS) 5 months prior to his presentation, but his symptoms persisted. A biopsy specimen was taken from the right nasal cavity, and extranodal natural killer/T-cell lymphoma, nasal type (ENKTL) was diagnosed. Two years after complete remission was achieved by chemoradiation therapy, he developed hemophagocytic lymphohistiocytosis (HLH) without recurrence of ENKTL. Epstein-Barr virus (EBV)-DNA copy number was relatively high and EBV-infected lymphocytes (CD8 + T cells) were detected in the peripheral blood. Pathological review of the biopsy specimens taken during ESS showed that CD8 + T cells with slightly atypia infiltrating the stroma were EBV positive. These findings suggested that the patient had underlying chronic active EBV infection (CAEBV) that caused the refractory chronic sinusitis, eventually developed into ENKTL, and also caused HLH. Clinicians should consider adult-onset CAEBV in the differential diagnosis of patients with refractory chronic sinusitis.