PD-L1 expression on neoplastic or stromal cells is respectively a poor or good prognostic factor for adult T-cell leukemia/lymphoma.

Programmed cell death ligand 1 (PD-L1) is expressed on both tumor and tumor-infiltrating nonmalignant cells in lymphoid malignancies. The programmed cell death 1 (PD-1)/PD-L1 pathway suppresses host antitumor responses, although little is known about the significance of PD-1/PD-L1 expression in the tumor microenvironment. To investigate the clinicopathological impact of PD-L1 expression in adult T-cell leukemia/lymphoma (ATLL), we performed PD-L1 immunostaining in 135 ATLL biopsy samples. We observed 2 main groups: 1 had clear PD-L1 expression in lymphoma cells (nPD-L1(+), 7.4% of patients), and the other showed minimal expression in lymphoma cells (nPD-L1(-), 92.6%). Within the nPD-L1(-) group, 2 subsets emerged: the first displayed abundant PD-L1 expression in nonmalignant stromal cells of the tumor microenvironment (miPD-L1(+), 58.5%) and the second group did not express PD-L1 in any cell (PD-L1(-), 34.1%). nPD-L1(+) ATLL (median survival time [MST] 7.5 months, 95% CI [0.4-22.3]) had inferior overall survival (OS) compared with nPD-L1(-) ATLL (MST 14.5 months, 95% CI [10.1-20.0]) (P = .0085). Among nPD-L1(-) ATLL, miPD-L1(+) ATLL (MST 18.6 months, 95% CI [11.0-38.5]) showed superior OS compared with PD-L1(-) ATLL (MST 10.2 months, 95% CI [8.0-14.7]) (P = .0029). The expression of nPD-L1 and miPD-L1 maintained prognostic value for OS in multivariate analysis (P = .0322 and P = .0014, respectively). This is the first report describing the clinicopathological features and outcomes of PD-L1 expression in ATLL. More detailed studies will disclose clinical and biological significance of PD-L1 expression in ATLL.

Expression of programmed death ligand 1 is associated with poor prognosis in myeloid sarcoma patients.

Myeloid sarcoma (MS) is a rare condition and is an extramedullary tumour of immature myeloid cells. It is now known that the programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) pathway suppresses the host antitumor responses and that these products are expressed on both tumour cells and tumour-infiltrating cells in various malignancies. However, little is known about the significance of PD-1/PD-L1 expression on tumour cells and tumour microenvironmental cells in MS. To investigate the clinicopathological significance of PD-1/PD-L1 expression in MS, we analyzed 98 patients by immunohistochemistry. Of these, 10.2% of cases had neoplastic tumour cells positive for PD-L1 (nPD-L1+ ). However, the rate of nPD-L1+ was <5% (range: 0.27 to 2.97%). On the other hand, PD-L1 expression on 1 or more of stromal cells in the tumour microenvironment (miPD-L1+ ) was observed in 37.8% of cases. Because all nPD-L1+ cases expressed PD-1 on less than 5% of tumour cells, we compared the miPD-L1+ and miPD-L1- groups. There was a correlation between miPD-L1+ status and the number of PD-1-expressing tumour -infiltrating lymphocytes (PD-1+ TILs; P = .0229). miPD-L1+ was found to be associated with poorer overall survival and progression-free survival (P = .00392, P = .00261, respectively). Multivariate analysis also confirmed miPD-L1+ to be an independent poor prognostic factor. In conclusion, our study indicated that the immunotherapy blocking the PD-1/PD-L1 pathway may improve the clinical outcome of MS.

Methotrexate-associated lymphoproliferative disorders with angioimmunoblastic T-cell lymphoma-like features accompanied by gamma-heavy chain disease in a patient with rheumatoid arthritis.

Although gamma heavy chain disease (γ-HCD) lesions occasionally morphologically resemble angioimmunoblastic T-cell lymphoma (AITL), no association has been described in detail due to the rarity of the disease. In this report, we present a rare manifestation of methotrexate (MTX)-associated lymphoproliferative disorders (LPDs) with AITL-like features accompanied by γ-HCD in a 75-year-old man with rheumatoid arthritis (RA). A biopsy specimen was evaluated using immunohistochemistry, clonal analyses of immunoglobulin VH and T-cell receptor γ gene rearrangements by polymerase chain reaction, and Sanger sequencing for confirmation of the structure of deleted γ-HCD clones. The histological features characterized by proliferation of CD4- and PD-1-positive medium-sized T cells and arborizing high endothelial venules together with numbers of small lymphocytes, eosinophils, plasma cells, and histiocytes in the background mimicked those of AITL, but did not completely fulfill the diagnostic criteria. Clonal analysis demonstrated that the specimen contained multiple LPDs of both B-cell and T-cell lineages. Sequence analysis confirmed the co-existence of a clone responsible for production of the abnormal heavy chain. This report provides new insights into the pathology of γ-HCD. Multiple host-derived factors (e.g., RA and/or use of MTX) may be responsible for the occurrence of LPDs of multiple lineages within a single lymph node.

Clinicopathological analysis of primary splenic diffuse large B-cell lymphoma.

Splenic infiltration is often seen in diffuse large B-cell lymphoma (DLBCL). However, primary splenic DLBCL is rare and studies on its clinicopathological features are limited. We assessed 66 cases of primary splenic DLBCL and 309 control DLBCL, not otherwise specified. Hepatitis C virus antibody prevalence, B symptoms, poor performance status and CD5 positivity differed significantly between the primary splenic DLBCL and control DLBCL groups. Primary splenic DLBCL cases were classified histopathologically into two groups [white pulp pattern (n = 46), red pulp pattern (n = 20)]. Survival analysis showed no difference in overall survival between the primary splenic DLBCL and the control group, but the former had a more favourable progression-free survival. In the examination of primary splenic DLBCL, the white pulp pattern was statistically associated with a lower performance status (2-4), and a lower CD5 positivity than the red pulp pattern. In the survival analysis, the red pulp pattern demonstrated poorer overall survival. Multivariate analysis of overall survival in primary splenic DLBCL cases identified CD5 positivity as an indicator of poor prognosis. Classifying primary splenic DLBCL into white and red pulp patterns was useful in terms of clinicopathological features and overall survival.

Expression of programmed cell death ligand 1 is associated with poor overall survival in patients with diffuse large B-cell lymphoma.

Programmed cell death ligand 1 (PD-L1) is expressed on both select diffuse large B-cell lymphoma (DLBCL) tumor cells and on tumor-infiltrating nonmalignant cells. The programmed cell death 1 (PD-1)/PD-L1 pathway inhibits host antitumor responses; however, little is known about how this pathway functions in the tumor microenvironment. The aim of this study was to determine the clinicopathological impact of PD-L1(+) DLBCL. We performed PD-L1/PAX5 double immunostaining in 1253 DLBCL biopsy samples and established a new definition of PD-L1(+) DLBCL. We also defined the criteria for microenvironmental PD-L1(+) (mPD-L1(+)) DLBCL (ie, PD-L1(-) DLBCL in which PD-L1(+) nonmalignant cells are abundant in the tumor microenvironment). Of the 273 patients whose clinical information was available, quantitative analysis of PD-1(+) tumor-infiltrating lymphocytes (TILs) was performed. The prevalence rates of PD-L1(+) and mPD-L1(+) DLBCL were 11% and 15.3%, respectively. Both PD-L1(+) and mPD-L1(+) DLBCL were significantly associated with non-germinal center B-cell (GCB) type and Epstein-Barr virus positivity. The number of PD-1(+) TILs was significantly higher in GCB-type tumors and lower in mPD-L1(-) and PD-L1(+) DLBCL. Patients with PD-L1(+) DLBCL had inferior overall survival (OS) compared with that in patients with PD-L1(-) DLBCL (P = .0009). In contrast, there was no significant difference in OS between mPD-L1(+) and mPD-L1(-) DLBCL (P = .31). The expression of PD-L1 maintained prognostic value for OS in multivariate analysis (P = .0323). This is the first report describing the clinicopathological features and outcomes of PD-L1(+) DLBCL. Immunotherapy targeting the PD-1/PD-L1 pathway should be considered in this distinct DLBCL subgroup.

Comparison of clinicopathological characteristics between T-cell prolymphocytic leukemia and peripheral T-cell lymphoma, not otherwise specified.

OBJECTIVES: T-cell prolymphocytic leukemia (T-PLL) is a very rare, aggressive T-cell neoplasm. Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is also a highly aggressive lymphoma. These two diseases can often be confused with each other; therefore, we aimed to determine the clinical and pathological differences between T-PLL and PTCL-NOS. METHODS: We analyzed 15 T-PLL and 91 PTCL-NOS patients and also compared clinical features between T-PLL and PTCL-NOS with leukemic presentation. Peripheral blood images and biopsy specimens were analyzed, and treatment responses were determined via imaging modalities. The clinicopathological characteristics were statistically compared. RESULTS: T-PLL cells were smaller in size than those of PTCL-NOS with leukemic presentation (P=.0068); moreover, PTCL-NOS cells with leukemic presentation were smaller than those of PTCL-NOS without leukemic presentation (P=.0017). Immunophenotypic patterns in T-PLL and PTCL-NOS were similar. Five-year overall survival rates of T-PLL and all PTCL-NOS patients were 57.5% and 36.8%, respectively. No significant differences were found in clinical manifestations or prognoses; T-PLL and PTCL-NOS with leukemic presentation had essentially equivalent characteristics. CONCLUSION: T-PLL and PTCL-NOS may share common biological and clinical characteristics in Japanese patients.

Spontaneous splenic rupture in a patient with light-chain deposition disease undergoing autologous peripheral blood stem cell transplantation.

Light-chain deposition disease (LCDD) is a rare plasma cell neoplasm that secretes an abnormal immunoglobulin light chain, which is deposited in tissues, leading to organ dysfunction. Spontaneous splenic rupture is a rare and life-threatening complication of treatment with granulocyte colony-stimulating factor (G-CSF). Herein, we describe spontaneous splenic rupture after the administration of lenograstim to a patient with LCDD undergoing autologous stem cell transplantation (ASCT). The patient was successfully treated by transcatheter embolization of the splenic artery, and long-term stringent complete remission was attained. Plasma cell neoplasms, including multiple myeloma with amyloidosis, are among the most commonly reported conditions associated with spontaneous splenic rupture in patients undergoing ASCT. This finding suggests that, in addition to the effect of G-CSF on the spleen, a combination of factors, including tissue vulnerability induced by the infiltration of abnormal immunoglobulins, may be involved in the pathogenesis of spontaneous splenic rupture. Notably, splenomegaly is not always evident in these patients. Surgical treatment may not be an option, because of severe myelosuppression, and thus less invasive treatment using transcatheter embolization may be feasible.

Danazol-induced peliosis hepatis accompanied by disseminated intravascular coagulation in a patient with myelodysplastic syndrome transformed from aplastic anemia.

Peliosis hepatis (PH) is a condition involving benign tumors pathologically characterized by multiple blood-filled cavities, mostly affecting the liver and spleen. Androgenic-steroids are widely used in patients with bone marrow failure syndromes (e.g.: aplastic anemia) and these patients are at increased risk of developing PH. Although patients with PH are generally asymptomatic, PH can progress to liver failure and even fatal spontaneous intraabdominal hemorrhage. Therefore, early diagnosis is critical in order to prevent life-threatening complications of PH. We herein report a patient with PH which had been treated with danazol, who presented with liver dysfunction and multiple hepatic lesions on imaging studies at the time of diagnosis. Although the patient presented with disseminated intravascular coagulation (DIC), a bone marrow biopsy revealed no evidence of leukemic transformation. The patient was diagnosed as having danazol-induced PH, and these abnormalities spontaneously resolved after the discontinuation of danazol. PH is one of the most important complications of long-term administration of androgenic-steroids. Although the mechanisms remain unclear, the multiple blood-filled cavities characteristic of PH may be responsible for the development of DIC. Therefore, monitoring of coagulation markers might also be a key strategy for early diagnosis of PH.

Clinicopathological features of double-hit B-cell lymphomas with MYC and BCL2, BCL6 or CCND1 rearrangements.

Double-hit (DH) lymphomas are B-cell lymphomas characterized by chromosomal rearrangements, specifically of MYC and either BCL2, BCL6 or CCND1. We reviewed 22 cases of DH lymphomas. BCL2/MYC DH lymphomas constituted the majority of these DH lymphomas (17 cases; 77%), followed by BCL6/MYC (2 cases; 9%) lymphomas. Assessing morphological features using the 2008 World Health Organization classification system, 15 cases (68%) were determined to be B-cell lymphoma, unclassifiable with features intermediate between diffuse large B-cell lymphoma (DLBCL) and Burkitt lymphoma (BCLU) (10 cases; 45%), or as DLBCL (5 cases; 23%), and 2 cases (9%) were classified as morphologically untransformed follicular lymphoma. Burkitt lymphoma was rare (1 case; 5%) among DH lymphomas. Nineteen cases were treated with R-CHOP or a high dose chemotherapy regimen. After a median follow-up of 11 months, 7 patients had died, and the 1-year survival rate was 62.5%. High dose chemotherapy did not improve the outcome. We suggest that screening of genetic variations to detect DH lymphomas is required in diagnosing all lymphomas, even those determined morphologically to be follicular lymphoma.

Low incidence of MYC/BCL2 double-hit in Burkitt lymphoma.

Translocations involving MYC are highly characteristic for Burkitt lymphoma (BL). BCL2 expression has also been found previously in about 10 to 20% of BL cases, and BCL2 translocation is a major mechanism for the deregulation of BCL2 expression in non-Hodgkin lymphomas. However, we know little about the incidence of MYC/BCL2 double-hit (DH) in BL. We examined BL cases to determine how frequently they contained BCL2 translocations in combination with MYC translocations using fluorescence in situ hybridization. We also determined the effect of BCL2 expression on clinical outcomes of BL. BCL2 translocations were detected in 3.5% (2/57 cases) of the cases, and BCL2 expression was detected in 33%. Two cases with BCL2 translocation also showed BCL2 expression. The incidence of BCL2 expression was significantly higher in patients 16 years of age and older (46%) than in patients under 16 years of age (6%). Among patients 16 years of age and older, we did not detect significant differences in overall survival with respect to BCL2 expression status. In conclusion, BCL2 translocation is a rare cytogenetic abnormality in BL, and BL probably accounts for only a small fraction of MYC/BCL2 DH lymphomas. BCL2 expression in BL is probably not associated with BCL2 translocations.

[CD20-positive plasma cell myeloma with lymphoplasmacytoid appearance mimicking low-grade B-cell lymphoma].

CD 20 positive myeloma with small lymphoplasmacytoid morphology is difficult to differentiate from mature B-cell lymphoma. A 71-year-old male was referred to our hospital because of osteolytic vertebral fractures and anemia. Urine was positive for Bence Jones protein, κ type. Bone marrow consisted of approximately 30% small lymphoplasmacytoid cells with scant cytoplasm, and these cells were positive for CD20, CD23 and CD138. FISH analysis revealed t(11;14)(CCND1/IGH). Myeloma with t(11;14) is closely associated with small lymphoplasmacytoid appearance and CD20 and CD23 expressions. The patient was diagnosed as having myeloma based on clinical and cytogenetic findings, and achieved VGPR (very good partial response) after treatment with lenalidomide.

CD5-positive follicular lymphoma characterized by CD25, MUM1, low frequency of t(14;18) and poor prognosis.

CD5-positive follicular lymphoma (FL), although rare, has been described in a number of case reports. However, a statistically valid, clinicopathological comparison between CD5-positive FL and CD5-negative FL has never been performed because of its rarity. We statistically compared clinicopathological characteristics of 22 cases of CD5-positive FL, diagnosed by immunohistochemistry, flow cytometry and morphological findings, with those of 62 cases of FL without CD5 expression (control cases). CD5-positive FL patients showed a higher tendency of peripheral blood involvement (P = 0.076) and a higher frequency of CD25 expression (P = 0.0004) and MUM1 protein expression (P = 0.0008), and a lower frequency of t(14;18)(q32;q21) (P = 0.017). The overall survival (OS) curve of CD5-positive FL was significantly worse than that of control cases (P = 0.0266), although progression-free survival curves did not show a significant difference (P = 0.7899). Moreover, CD5 expression was shown to be an independent poor prognostic factor for OS in both univariate analysis [Hazard Ratio (HR), 3.63; P = 0.0464] and multivariate analysis (HR, 57.16; P = 0.0001). CD5-positive FL showed different clinicopathological characteristics from FL lacking CD5 expression. These results suggest that CD5-positive FL should be considered a different type of FL, and its clinicopathological management should be conducted differently.

[Successful treatment with oral low-dose sobuzoxane and etoposide combined with rituximab in an elderly patient with HHV-8-negative primary effusion lymphoma-like lymphoma].

Primary effusion lymphoma (PEL) is a rare B-cell lymphoma, characterized by human herpes virus 8 (HHV8) infection and serous effusions without detectable tumor masses. However, cases with HHV8 unrelated PEL have also been reported, mainly in Japan, and these are referred to as PEL-like lymphoma (PEL-LL). We describe a 70-year-old man with cardiac comorbidity who developed PEL-LL with pleural effusion. The patient achieved a complete response (CR) after treatment with oral low-dose sobuzoxane and etoposide combined with rituximab. To date, the patient has been in CR for about 7 months without chemotherapy. PEL-LL reportedly has a better prognosis than PEL. Because PEL-LL is positive for CD20, unlike PEL, combination therapy including rituximab may be effective. PEL-LL mainly affects elderly people, so that further investigation of tolerable and effective regimens is required.

Methotrexate/iatrogenic lymphoproliferative disorders in rheumatoid arthritis: histology, Epstein-Barr virus, and clonality are important predictors of disease progression and regression.

OBJECTIVES: Patients with rheumatoid arthritis (RA) may develop lymphoproliferative disorders (RA-LPD). Immunosuppressive states due to methotrexate (MTX) and Epstein-Barr virus (EBV) reactivation have been regarded as causes. Sometimes spontaneous regression occurs after withdrawal of MTX. The objective of this study was to identify factors predictive of relapse and survival in patients with RA-LPD, and spontaneous regression in patients with RA-LPD treated with MTX (MTX-LPD). METHODS: We evaluated the clinicopathological features, clinical characteristics, and treatment outcomes in 102 cases of RA-LPD. In addition, EBV infection and clonality of immunoglobulin heavy chain gene (IGH) were analyzed by in situ hybridization and polymerase chain reaction, respectively. RESULTS: The 102 cases included patients with diffuse large B-cell lymphoma (DLBCL; n = 53), Hodgkin lymphoma (n = 9), polymorphic B-cell LPD (n = 20), reactive lymphadenitis (n = 11), peripheral T-cell lymphoma (PTCL; n = 4), composite lymphoma (n = 2), and follicular lymphoma (n = 3). EBV was detected in 60% (56/93) of patients. Spontaneous regression occurred in 59% (28/47) of patients in whom MTX was withdrawn. Regression was associated with EBV positivity (P = 0.007) and non-DLBCL (P = 0.006), but not with MTX amount and other clinical features. Monoclonal bands of IGH were observed in 31 of 74 cases. In patients with DLBCL, poor disease-free survival (P = 0.05) was associated with clonality of IGH. In all patients, factors predictive of shorter survival were age (>70 yr) and histological type of DLBCL. CONCLUSIONS: Histology, EBV positivity, and monoclonality of IGH are useful for predicting clinical outcomes in patients with RA-LPD.

Comparison of CD20 expression in B-cell lymphoma between newly diagnosed, untreated cases and those after rituximab treatment.

Few studies have statistically investigated reduced CD20 expression in B-cell lymphoma after rituximab therapy and genomic mutation of CD20 associated with reduction. We examined CD20-positive rate in follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) by flow cytometry (FCM) and immunohistochemical staining (IHS), comparing 138 cases after rituximab therapy with 360 initial, not yet treated cases. Sequence analysis of exons 3 to 8 of CD20 was performed on 22 cases with low CD20-positive rate after rituximab treatment. The results showed a statistical correlation between CD20-positive rate in FCM and IHS. By FCM, the CD20-positive rate among post-rituximab cases was significantly lower than among initial cases in DLBCL, non-germinal center origin B-cell type (average values [avg] 57.8 and 87.9, respectively) (P < 0.0001), FL2 (avg, 93.9; 103.2) (P = 0.0083), and FL3A (avg, 90.6; 100.7) (P = 0.033). Stratified analyses of post-rituximab cases showed significantly lower CD20-positive rate in cases that were resistant at the start of the treatment and cases with progressive disease during rituximab therapy before biopsy. Sequence analysis showed silent mutation of exon 4 (632 C/T) in seven cases, although this number was not statistically significant. These results suggest the influence of B-lymphoma subtype and a therapeutic effect before biopsy on CD20 expression at relapse and contribute to a better therapeutic approach for relapse cases after rituximab therapy.

A spindle cell variant of diffuse large B-cell lymphoma is characterized by T-cell/myofibrohistio-rich stromal alterations: analysis of 10 cases and a review of the literature.

Spindle-shaped diffuse large B-cell lymphoma (Sp-DLBCL) has been recognized as a rare morphologic variant of DLBCL. However, the biological processes that contribute to the specific features of Sp-DLBCL remain poorly understood. In this study, a combined immunophenotypic and genetic analysis was performed in 10 Sp-DLBCL. First, we investigated several unique markers for anaplasia (CD30, ALK, CD68, and EBER-ISH), mesenchyma (SMA, desmin, and vimentin), and B-cell differentiation (CD10, BCL6, and MUM1). We also performed conventional cytogenetic and fluorescence in situ hybridization studies to look for common chromosomal break points (BCL2, BCL6, and MYC). We found that most Sp-DLBCLs were germinal center B cell-like and that none had any other specific phenotypes or any karyotypic abnormalities. Instead, T cells, CD68-positive macrophages and SMA-positive myofibroblasts were significantly increased in Sp-DLBCL when compared with conventional GCB origin DLBCL cases (n = 10) (P = 0.012, P < 0.001, and P < 0.0001, respectively). To further characterize Sp-DLBCL, we next compared the expression of fibroblast growth factor 2 (FGF2) and transforming growth factor-ß1 (TGFß1) between the two types of DLBCL. Finally, we confirmed that the number of FGF2- and TGFß1-positive stromal cells was markedly increased in Sp-DLBCL and that the difference between these and conventional GCB origin DLBCLs was significant (P < 0.0001 and P = 0.0017, respectively). Thus, T-cell/myofibrohistio-rich stromal alterations in Sp-DLBCL, especially those mediated by TGFß1 and FGF2, may play a role in the transition of lymphoma cells into those with spindle-shaped features.

Clinicopathological features and prognostic significance of CXCL12 in blastic plasmacytoid dendritic cell neoplasm.

BACKGROUND: Blastic plasmacytoid dendritic cell neoplasm (BPDC) is a rare hematologic neoplasm, which almost always involves the skin and shows poor prognosis. OBJECTIVE: The aim of our study was to enhance BPDC diagnosis and indications for prognosis. METHODS: This study involved 26 patients with BPDC. To investigate the histogenesis of BPDC, we reviewed the clinical features and stained markers of various hematopoietic lineages, chemokines, and their receptors. RESULTS: Bone-marrow infiltration was detected in 13 of the 19 cases examined and leukemic changes in 18. Complete remission was achieved in 14 cases, but more than half of the patients showed recurrence within a short time, and 14 patients died of the disease after 1 to 25 months (mean 8.5 months). Positivity for CD123 was detected in 18 of 24 cases and for T-cell leukemia 1 in 18 of 22 cases. Of the chemokines and their receptors, 8 of 15 skin biopsy specimens proved to be positive for CXCL12. Leukemic change subsequent to skin lesions occurred in 7 of 8 CXCL12-positive cases (87.5%) and in 3 of 6 CXCL12-negative cases (50%). Seven of the 8 CXCL12-positive patients (87.5%) and two of the 6 CXCL12-negative patients (33.3%) have died, whereas one of 8 CXCL12-positive patients (12.5%) and 4 of 6 CXCL12-negative patients (66.7%) remain alive. LIMITATIONS: The number of patients was limited. CONCLUSIONS: We speculate that the presence of CXCL12-positive cells in the skin may be associated with leukemic change and a poor prognosis.

Malignant lymphoma of the spleen in Japan: a clinicopathological analysis of 115 cases.

Primary splenic lymphoma is rare, but malignant lymphoma often produces a lesion in the spleen as part of systemic disease. The frequency of splenic malignant lymphoma in Japan is unknown. We classified 184 specimens of the spleen according to the World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues, 4th edition (2008). Of the 184 specimens, 115 were determined to be lymphoid neoplasm (62.5%). The most common subtype of lymphoid neoplasm was diffuse large B-cell lymphoma (DLBCL) (46 cases), followed by splenic marginal zone lymphoma (SMZL) (28 cases), follicular lymphoma (11 cases), splenic B-cell lymphoma, unclassifiable (SBL-U) (6 cases) and peripheral T-cell lymphoma, not otherwise specified (4 cases). In the SBL-U subtype, 5 of 6 cases were splenic diffuse red pulp small B-cell lymphoma, and one case was the hairy cell leukemia variant. Analysis of clinical features revealed that patients with DLBCL had a higher age, high lactate dehydrogenase and tumor formation in the spleen. On the other hand, it was found that patients with SMZL had splenomegaly but no discrete tumor formation. Most of the patients with SBL-U presented with thrombocytopenia, bone marrow involvement, and advanced stage. Our study revealed the frequency and clinical features of splenic malignant lymphoma in Japan.

FOXP3(+) regulatory and TIA-1(+) cytotoxic T lymphocytes in HIV-associated Hodgkin lymphoma.

Human immunodeficiency virus (HIV) infects CD4(+) lymphocytes, leading to a development of malignant lymphomas, such as HIV-associated Hodgkin Lymphoma (HIV-HL). This study aimed to assess the differences in cellular composition of the inflammatory reactive background of HIV-HLs. We examined infiltrating T lymphocytes, specifically regulatory T cells, cytotoxic cells, Epstein-Barr virus (EBV) related antigens and HIV-receptor CCR5. In all HIV-HL cases, Hodgkin and Reed-Sternberg (HRS) cells showed EBER1 expression, LMP-1 staining positivity and EBNA-2 staining negativity, except for one case which showed LMP-1 staining negativity. Our histological findings indicate the percentage of CD8(+) , TIA-1(+) lymphocytes was significantly higher in HIV-HL than in non-HIV-HL cases (P < 0.05). On the other hand, the percentage of CD4(+) , FOXP3(+) lymphocytes was significantly lower in HIV-HL than in non-HIV-HL cases (P < 0.05) but present. The percentage of CCR5(+) lymphocytes was significantly lower in HIV-HL than in non-HIV-HL cases (P < 0.05). Usually, CD4(+) and CCR5(+) lymphocytes are reported to be rarely detected in HIV-associated non-Hodgkin lymphomas, but the presence of CD4(+) and/or FOXP3(+) lymphocytes may be implicated in the pathogenesis of HL. In addition, although additional CD8(+) lymphocytes are probably not EBV-LMP specific cytotoxic T-cells, these lymphocytes may also well be involved in the pathogenesis of HIV-HL.

Clinicopathological analysis of a composite lymphoma containing both T- and B-cell lymphomas.

Composite lymphomas (CLs) have been reported in 1-4.7% of all lymphomas, however, CLs containing both T- and B-cell lymphomas (CTBLs) are very rare. Here, we examined the clinical and pathological features of 29 CTBLs. These CTBLs included 21 patients with angioimmunoblastic T-cell lymphoma (AITL) and diffuse large B-cell lymphoma (DLBCL), two with adult T-cell leukemia/lymphoma and DLBCL, one with AITL and Follicular lymphoma, one with Lennert lymphoma and DLBCL, one with subcutaneous panniculitis-like T-cell lymphoma and DLBCL, one with peripheral T-cell lymphoma (PTCL) and DLBCL, one with cutaneous T-cell lymphoma and DLBCL, and one with PTCL and chronic lymphocytic leukemia. Eighteen of 27 patients (67%) were shown to be Epstein-Barr virus (EBV)-encoded RNA-positive in their B-cell lymphoma component. T-cell and B-cell clonality were confirmed by flow cytometry, Southern blot analysis, and/or polymerase chain reaction (PCR). Using Southern blot analysis, clonal immunoglobulin heavy chain (IgH) and T-cell receptor (TCR) rearrangements were detected in 11 of 21 and 15 of 24 cases, respectively. Using PCR analysis, clonal IgH and TCR rearrangements were detected in 7 of 8 and 7 of 7 Southern blot-negative cases, respectively. Our results suggested that PCR analysis was useful in diagnosing CTBL.