Whole-genome CRISPR screening identifies molecular mechanisms of PD-L1 expression in adult T-cell leukemia/lymphoma

ABSTRACT

Adult T-cell leukemia/lymphoma (ATLL) is an aggressive T-cell malignancy with a poor prognosis and limited treatment options. Programmed cell death ligand 1(PD-L1) is recognized to be involved in the pathobiology of ATLL. However, what molecules control PD-L1 expression and whether genetic or pharmacological intervention might modify PD-L1 expression in ATLL cells are still unknown. To comprehend the regulatory mechanisms of PD-L1 expression in ATLL cells, we performed unbiased genome-wide clustered regularly interspaced short palindromic repeat (CRISPR) screening in this work. In ATLL cells, we discovered that the neddylation-associated genes NEDD8, NAE1, UBA3, and CUL3 negatively regulated PD-L1 expression, whereas STAT3 positively did so. We verified, in line with the genetic results, that treatment with the JAK1/2 inhibitor ruxolitinib or the neddylation pathway inhibitor pevonedistat resulted in a decrease in PD-L1 expression in ATLL cells or an increase in it, respectively. It is significant that these results held true regardless of whether ATLL cells had the PD-L1 3' structural variant, a known genetic anomaly that promotes PD-L1 overexpression in certain patients with primary ATLL. Pevonedistat alone showed cytotoxicity for ATLL cells, but compared with each single modality, pevonedistat improved the cytotoxic effects of the anti-PD-L1 monoclonal antibody avelumab and chimeric antigen receptor (CAR) T cells targeting PD-L1 in vitro. As a result, our work provided insight into a portion of the complex regulatory mechanisms governing PD-L1 expression in ATLL cells and demonstrated the in vitro preliminary preclinical efficacy of PD-L1-directed immunotherapies by using pevonedistat to upregulate PD-L1 in ATLL cells.

An anti-CD19/CTLA-4 switch improves efficacy and selectivity of CAR T cells targeting CD80/86-upregulated DLBCL

Chimeric antigen receptor T cell (CAR T) therapy is a potent treatment for relapsed/refractory (r/r) B cell lymphomas but provides lasting remissions in only ∼40% of patients and is associated with serious adverse events. We identify an upregulation of CD80 and/or CD86 in tumor tissue of (r/r) diffuse large B cell lymphoma (DLBCL) patients treated with tisagenlecleucel. This finding leads to the development of the CAR/CCR (chimeric checkpoint receptor) design, which consists of a CD19-specific first-generation CAR co-expressed with a recombinant CTLA-4-linked receptor with a 4-1BB co-stimulatory domain. CAR/CCR T cells demonstrate superior efficacy in xenograft mouse models compared with CAR T cells, superior long-term activity, and superior selectivity in in vitro assays with non-malignant CD19+ cells. In addition, immunocompetent mice show an intact CD80-CD19+ B cell population after CAR/CCR T cell treatment. The results reveal the CAR/CCR design as a promising strategy for further translational study.

Clinicopathological analysis of immunohistochemical expression of immune checkpoint molecules in follicular lymphoma

Follicular lymphoma (FL) is characterized by an indolent clinical course and a high relapse rate, and often exhibits a diffuse pattern beyond the follicular area. Our group previously reported that immune checkpoint (ICP) pathways, such as programmed cell death (PD-1) and programmed death ligand 1 (PD-L1), are poor prognostic factors for diffuse large B-cell lymphoma and adult T-cell leukemia/lymphoma.In this study, the association between the expression of multiple ICP molecules according to immunohistochemistry and clinicopathological features in FL was determined via immunostaining of 173 biopsy samples. Membrane and/or cytoplasm expression of CD86 (nCD86) and PD-L1 (nPD-L1) was found in tumor cells, whereas PD-1 (miPD-1), Galectin-9 (miGalectin-9), OX40 (miOX40), CTLA-4 (miCTLA-4), Tim-3 (miTim-3), OX40L (miOX40L), and LAG-3 (miLAG-3) were expressed in non-neoplastic stromal cells. MiPD-1 expression was significantly higher in the follicular area than in the diffuse area (p=0.0450). Expression of miOX40 and miCTLA-4 was significantly higher in the diffuse area than in the follicular area (respectively, p=0.0053 and p=0.0092). MiTim-3 tended to be higher in the diffuse area than in the follicular area (p=0.0616). MiTim-3 was significantly higher in relapse cases than in new-onset cases (p=0.0440); miLAG-3 tended to be higher in relapse cases than in new-onset cases (p=0.0622, not significant). The miOX40L-high FL group had a significantly worse overall survival than the miOX40L-low group (p=0.0320).The expression of multiple ICP molecules on several cells reflects activated anti-tumor immunity and the unique FL microenvironment. Further studies on gene expression or genomic abnormalities will reveal the clinical and biological significance of ICP molecules in FL. This article is protected by copyright. All rights reserved.

RHOA mutation in follicular T-cell lymphoma: Clinicopathological analysis of 16 cases

Follicular T-cell lymphoma (FTCL) is considered to originate from follicular helper T-cell (Tfh) cells. Angioimmunoblastic T-cell lymphoma (AITL) and peripheral T-cell lymphomas with the Tfh phenotype, derived from Tfh cells, often harbor RHOA G17V mutation. We investigated whether RHOA mutations affect the clinicopathological features of FTCL. We performed deep sequencing and Sanger sequencing for RHOA exon 2 in 16 cases of FTCL. Nine cases showed RHOA mutations, including eight with c.G50T, p.Gly17Val and one with c.G50A, p.Gly17Glu, c.A52G, p.Lys18Glu, c.T102C, p.Tyr34Tyr and c.G145T, p.Asp49Tyr. Compared to the RHOA mutation-negative group, the RHOA mutation-positive group had a higher tendency for B-immunoblasts (P = 0.06), the AITL component (P = 0.09), and higher positive rate for CD10 (P = 0.09) and BCL6 (P = 0.09), and a significantly higher positive rate for CXCL13 (P = 0.04). Although not statistically significant, the RHOA mutation-positive group showed higher values for almost all characteristic AITL features. There was no significant difference in overall survival between RHOA mutation-positive and -negative groups. The RHOA mutation may play an important role in clinicopathological characteristics and lymphomagenesis of FTCL. A more detailed investigation is needed to highlight the importance of RHOA mutations in FTCL.

Lymphocyte-monocyte ratio (LMR) can predict bendamustine therapeutic efficacy in low-grade B-cell lymphoma

INTRODUCTION

Bendamustine has been reported to be effective against low-grade B-cell lymphoma. We examined the effect of bendamustine on the lymphocyte-monocyte ratio (LMR) in low-grade B-cell lymphoma patients.

METHODS

We retrospectively reviewed 127 cases of first line or relapse/refractory low-grade B-cell lymphoma in three individual institutions (Asahikawa Municipal Hospital, Aiiku Hospital, and Hakodate Municipal Hospital). Only patients who had received at least three courses of bendamustine therapy were selected; the LMR was evaluated at starting the initial course of bendamustine therapy. Time to next treatment (TTNT) was used to ascertain the efficacy of bendamustine therapy.

RESULTS

Follicular lymphoma (FL), at 68.5% (87/127), is the most common histological subtype of low-grade B-cell lymphoma. The receiver operating characteristic (ROC) curve for the LMR showed a cutoff value of 2.0, and 33 cases (26.0%) had an LMR ≤2.0. Cases with LMR ≤2.0 had a significantly earlier progression than those with LMR > 2.0, based on the TTNT (P = .0007). Additionally, LMR ≤2.0 indicates earlier progression in TTNT when comparing only FL and low-grade B-cell lymphoma cases without FL (P = .007, 0.002). For multivariate analysis, the factors associated with an LMR ≤2.0 (HR, 2.741; 95% CI, 1.4330-5.245; P = .002) were considered as early progression factors with regard to the TTNT.

CONCLUSION

Lymphocyte-monocyte ratio effectively predicts the efficacy of bendamustine therapy for low-grade B-cell lymphoma, particularly FL; its application may improve treatment strategies for this disease.

Clinicopathological analysis of splenic red pulp low-grade B-cell lymphoma

Primary splenic low-grade B-cell lymphoma of the red pulp comprises hairy cell leukemia (HCL) and splenic B-cell lymphoma/leukemia, unclassifiable (SPLL-U). SPLL-U is a rare disease that includes subtypes of a hairy cell leukemia-variant (HCL-v), splenic diffuse red pulp small B-cell lymphoma (SDRPL) and other types that are known as narrow sense SPLL-U (SPLL-U-NS). Notably, limited information is available regarding the BRAF mutation (V600E) and cyclin D3 expression in subtypes of SPLL-U. Therefore, we performed a pathological analysis of the BRAF mutation (V600E) and characterized pathological features of SPLL-U. We reviewed the pathological findings of 12 SPLL-U cases. The 12 cases considered included two cases of HCL-v, six cases of SPLL-U-NS and four undetermined cases. The BRAF mutation (V600E) was detected in three cases, which were all SPLL-U-NS. Cases with the BRAF mutation (V600E) have increased levels of CD103 expression and decreased cyclin D3 and cyclin D1 expression compared with cases that lacked the BRAF mutation. These findings suggest that the BRAF mutation might play a significant role in SPLL-U. Therefore, the significance of the BRAF mutation should be evaluated via genomic or transcriptional analyses of a large cohort of SPLL-U patients.

Clinicopathological features of in situ follicular neoplasm and relations with follicular lymphoma in Japan

This study aims to investigate the clinicopathological features of in situ follicular neoplasm (ISFN) in Japan. ISFN is a rare condition formerly considered as an early precursor of follicular lymphoma (FL). This is a first original report of ISFN from Asian country. We reviewed 19 biopsy samples of ISFN. ISFNs were categorized into two groups: (1) ISFN, consisting of ISFN with strong positivity for BCL-2 immunohistochemical staining (IHC), and obvious translocation of BCL-2; and (2) ISFN-like FL, featuring cases without obvious translocation but having morphological features and characteristic IHC findings of ISFN. As control, we adopted obvious FL. For some cases showing coexisting ISFN and FL lesions in the same lymph node, we could conduct further clonality analysis for each lesion. Nine of the 19 cases of ISFN coexisted with FL or had a history of overt B- or T-cell lymphoma including FL. Statistical comparison among ISFN-like FL and FL showed no significant differences in pathological features. Molecular analysis suggested that ISFN lesion and FL lesion in the same lymph node each have a different clonality. ISFN coexists or associates with other overt lymphomas frequently.

Useful prognostic tools based on complete blood cell counts in diffuse large B-cell lymphoma

INTRODUCTION

Diffuse large B-cell lymphoma (DLBCL) is the most frequent lymphoma. Three prognostic factors are widely used in DLBCL: International Prognostic Index (IPI), Revised-IPI (R-IPI), and National Comprehensive Cancer Network-IPI (NCCN-IPI).

METHOD

We established a prognostic model using peripheral blood absolute lymphocyte/absolute monocyte counts ratio (LMR), hemoglobin, and platelet counts obtained from complete blood cell counts (CBC) data at diagnosis based on 214 cases of DLBCL who received more than one course of R-CHOP therapy at a single institution.

RESULTS

The cutoff values for using the receiver operating characteristics (ROC) curve for LMR, hemoglobin, and platelet counts were 1.6, 100 g/L, and 150 × 10⁹ /L, respectively. Stratification was performed using the three factors (LMR < 1.6, hemoglobin < 100 g/L, and platelet counts < 150 × 10⁹ /L). CBC Group 1 (none of the 3 factors) included 92 cases, CBC Group 2 (1 or 2 of these factors) included 108 cases, and CBC Group 3 (all 3 factors) included 11 cases. The 5-year OS rates were 78.2%, 60.9%, and 10.1%, respectively. In multivariate analysis, CBC Group 3 (hazard ratio, 2.9760; 95% confidence interval, 1.2670-6.991; P = .01) were prognostic factors for OS. CBC Group 3 had factors based on which the further stratification of the poor prognosis group into IPI high-risk and R-IPI poor-risk groups (P = .01, <.0001, respectively) was possible.

CONCLUSIONS

In DLBCL, combination of three CBC parameters has the potential to be a useful prognostic tool.

Clinicopathological features of HCV-positive splenic diffuse large B cell lymphoma

The hepatitis C virus (HCV) is a single-stranded RNA virus which is thought to be involved in the onset of B cell lymphoma. HCV-positive diffuse large B cell lymphoma (DLBCL) has been reported to clinically manifest in extranodal lesions (e.g., in the liver, spleen, and stomach). Here, we investigated HCV-positive and -negative primary splenic DLBCL (p-spDLBCL) and non-primary splenic DLBCL (ordinary DLBCL). Furthermore, to examine HCV lymphomagenesis, RNA in situ hybridization (ISH), RT-PCR (reverse-transcription polymerase chain reaction), and NS3 immunostaining of HCV viral nonstructural proteins were performed. HCV-positive p-spDLBCL patients presented fewer B symptoms (asymptomatic) and better performance status, with elevated presence of splenic macronodular lesions and more germinal center B cell (GCB) sub-group cases than HCV-negative p-spDLBCL patients. However, HCV-positive ordinary DLBCL patients were found to have more non-GCB sub-group cases than HCV-negative ordinary DLBCL patients. HCV-positive DLBCL patients showed 20.6% (7/34) NS3 positivity, 16.7% (1/6) HCV-RNA in situ positivity, and 22.2% (2/9) detection of HCV-RNA in tumor tissue by RT-PCR. Splenic samples were found to have a higher frequency of HCV detection than lymph node samples, thus suggesting that HCV may be closely related to lymphomagenesis, especially in splenic lymphoma.

Analysis of GNA13 Protein in Follicular Lymphoma and its Association With Poor Prognosis

GNA13 is a G protein involved in modulating tumor proliferative capacity, infiltration, metastasis, and migration. Genomic alteration of GNA13 was frequently observed in follicular lymphoma (FL). In this study, we examined 167 cases of FL by immunostaining of GNA13 using tissue microarray to evaluate the clinical significance. There were 26 GNA13-positive cases (15.6%) and 141 GNA13-negative cases (84.4%). GNA13-positive cases had a higher incidence of early progression of disease for which disease progression was recognized within 2 years compared with GNA13-negative cases (P=0.03). There were no significant differences in other clinicopathologic factors including histological grade, BCL2-IGH translocation, immunohistochemical phenotype, and Follicular Lymphoma International Prognostic Index. In addition, overall survival and progression-free survival were poorer in GNA13-positive cases than in GNA13-negative cases (P=0.009 and 0.005, respectively). In multivariate analysis, GNA13 positivity was found to be a poor prognostic factor for overall survival and progression-free survival. Thus, GNA13 protein expression was an independent prognostic factor and may affect disease progression in FL.

Targeting the HTLV-I-Regulated BATF3/IRF4 Transcriptional Network in Adult T Cell Leukemia/Lymphoma

Adult T cell leukemia/lymphoma (ATLL) is a frequently incurable disease associated with the human lymphotropic virus type I (HTLV-I). RNAi screening of ATLL lines revealed that their proliferation depends on BATF3 and IRF4, which cooperatively drive ATLL-specific gene expression. HBZ, the only HTLV-I encoded transcription factor that is expressed in all ATLL cases, binds to an ATLL-specific BATF3 super-enhancer and thereby regulates the expression of BATF3 and its downstream targets, including MYC. Inhibitors of bromodomain-and-extra-terminal-domain (BET) chromatin proteins collapsed the transcriptional network directed by HBZ and BATF3, and were consequently toxic for ATLL cell lines, patient samples, and xenografts. Our study demonstrates that the HTLV-I oncogenic retrovirus exploits a regulatory module that can be attacked therapeutically with BET inhibitors.

Unilateral conjunctival infiltration of Adult T-cell leukemia/lymphoma. Case report and literature review

Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell lymphoma caused by human T-cell leukemia virus type 1 infection. Although conjunctival lymphoma is commonly reported with B-cell lymphoma, it rarely occurs in cases of ATLL. A 73-year-old Japanese female patient was admitted to our institution with evidence of abnormal lymphocytes, lymphadenopathy, and lung nodular lesions. Acute type ATLL was diagnosed, and therapy following the mLSG15 protocol was initiated. At the end of the second course, new bone lesions were detected. A modified treatment regimen was scheduled, but was postponed due to the appearance of gastrointestinal symptoms. Close observation resulted in a diagnosis of cytomegalovirus enteritis. One month after the diagnosis, the patient developed pain and discomfort in her left eye, which was determined to be due to a bulbar conjunctival tumor. Pathological findings revealed conjunctival infiltration of ATLL. Mogamulizumab treatment was initiated and was successful in eradicating the conjunctival lesions after the first course. However, at the end of the third course of therapy, pancytopenia was noted. Therefore, mogamulizumab therapy was discontinued, and the patient was on follow-up observation. Although there was no relapse of the conjunctival lesions, the patient died 1 year after the initial diagnosis, following therapy resistance.

Clinicopathological analysis of polyploid diffuse large B-cell lymphoma

Polyploid chromosomes are those with more than two sets of homologous chromosomes. Polyploid chromosomal abnormalities are observed in various malignant tumors. The prognosis in such cases is generally poor. However, there are no studies examining the prognosis of diffuse large B-cell lymphoma (DLBCL) with polyploid chromosomal abnormalities. Therefore, we statistically compared the clinicopathological features between polyploid DLBCL and DLBCL without polyploid abnormalities. Herein, 51 polyploid DLBCL and 53 control (without polyploid chromosomal abnormalities) cases were examined. G-banding method was employed to define polyploidy by cytogenetic analysis. Subsequently, flow cytometric immunophenotyping and immunohistochemical staining were performed. Polyploid DLBCL was defined as DLBCL with either near-tetraploid or greater number of chromosomes, as detected by the G-band. In a survival analysis, a significantly worse overall survival (OS) was observed for polyploid DLBCL (p = 0.04; p = 0.02 in cases who received R-CHOP regimens). In a multivariate analysis of OS, polyploid chromosomal abnormalities were an independent prognostic factor. Our results suggest that polyploid chromosomal abnormalities detected through G-band may represent a new poor prognostic factor for DLBCL.

Expression pattern of immunosurveillance-related antigen in adult T cell leukaemia/lymphoma

AIMS

Adult T cell leukaemia/lymphoma (ATLL) is an aggressive malignancy with a poor prognosis. Human leucocyte antigen (HLA) and β2 microglobulin (β2M) serve as key molecules in tumour immunity, and their expression is reduced frequently in tumour cells. Programmed cell death (PD)-1/PD-ligand1 (PD-L1) interactions play a role in escape of tumour cells from T cell immunity. Therefore, this study aimed to determine the clinicopathological relevance of HLA and β2M expressions in ATLL cells and PD-L1 expression in lymphoma or stromal cells and predict the overall survival of patients with ATLL.

METHODS AND RESULTS

We analysed a total of 123 biopsy samples from patients newly diagnosed with ATLL by using immunohistochemical analysis. Of the patients enrolled, 91 (74%) were positive for HLA (in cell membrane, 60 patients), 89 (72%) were positive for β2M (in cell membrane, 54 patients) and 48 (39%) were positive for both HLA and β2M in the cell membrane (HLA^m+ β2M^m+ ). No significant clinical differences other than prognosis were found between the HLA^m+ β2M^m+ group and the other groups. Immunophenotypical evaluation revealed significantly higher rates of CD30-positive lymphoma cells (P = 0.003) and PD-L1-positive stromal cells in microenvironments (miPD-L1^high ) (P = 0.011) of the HLA^m+ β2M^m+ group than in the other groups. The HLA^m+ β2M^m+ group had a significantly better prognosis that the other groups (P = 0.0096), and patients showing HLA^m+ β2M^m+ with miPD-L1^high had the most favourable prognosis among all groups.

CONCLUSIONS

The membranous expression of HLA and β2M is likely to reflect the immune response and would be useful to predict prognosis before starting ATLL therapy.

A distinct subtype of Epstein-Barr virus-positive T/NK-cell lymphoproliferative disorder: adult patients with chronic active Epstein-Barr virus infection-like features

The characteristics of adult patients with chronic active Epstein-Barr virus infection are poorly recognized, hindering early diagnosis and an improved prognosis. We studied 54 patients with adult-onset chronic active Epstein-Barr virus infection diagnosed between 2005 and 2015. Adult onset was defined as an estimated age of onset of 15 years or older. To characterize the clinical features of these adults, we compared them to those of 75 pediatric cases (estimated age of onset <15 years). We compared the prognosis of adult-onset chronic active Epstein-Barr virus infection with that of patients with nasal-type (n=37) and non-nasal-type (n=45) extranodal NK/T-cell lymphoma. The median estimated age of onset of these lymphomas was 39 years (range, 16–86 years). Compared to patients with pediatric-onset disease, those in whom the chronic active Epstein-Barr virus infection developed in adulthood had a significantly decreased incidence of fever (P=0.005), but greater frequency of skin lesions (P<0.001). Moreover, hypersensitivity to mosquito bites and the occurrence of hydroa vacciniforme were less frequent in patients with adult-onset disease (P<0.001 and P=0.0238, respectively). Thrombocytopenia, high Epstein-Barr virus nuclear antigen antibody titer, and the presence of hemophagocytic syndrome were associated with a poor prognosis (P=0.0087, P=0.0236, and P=0.0149, respectively). Allogeneic hematopoietic stem cell transplantation may improve survival (P=0.0289). Compared to pediatric-onset chronic active Epstein-Barr virus infection and extranodal NK/T-cell lymphoma, adult-onset chronic active Epstein-Barr virus infection had a poorer prognosis (P<0.001 and P=0.0484, respectively). Chronic active Epstein-Barr virus infection can develop in a wide age range, with clinical differences between adult-onset and pediatric-onset disease. Adult-onset chronic active Epstein-Barr virus infection is a disease with a poor prognosis. Further research will be needed.

Hepatitis C virus infection is an independent prognostic factor in follicular lymphoma

Hepatitis C virus (HCV) is a single-stranded RNA virus that not only affects hepatocytes, by B cells as well. It is thought that HCV is involved in the onset of B-cell lymphoma. The clinicopathological characteristics of HCV-positive diffuse large B-cell lymphoma (DLBCL) and HCV-positive splenic marginal zone lymphoma (SMZL) are known, but there has been no report on HCV-positive follicular lymphoma (FL). In this study, the clinicopathological characteristics of HCV-positive FL were examined in 263 patients with FL who were classified into a HCV-positive group with HCV antibody and negative groups without one. The number of patients with HCV-positive FL and HCV-negative FL was 10 (3.8%) and 253 (96.2%), respectively. The patients with HCV-positive FL commonly had more than one region of lymphadenopathy, Ann Arbor stage III/IV, hemoglobin <120 g/l, elevated lactate dehydrogenase level, and high-risk categorization of Follicular Lymphoma International Prognostic Index (FLIPI) than in patients with HCV-negative FL. Overall survival and progression-free survival were poorer in patients with HCV-positive FL than in those with HCV-negative FL (p < 0.0001 and 0.006, respectively). Also, multivariate analysis revealed that positive HCV antibody was a poor prognostic factor of OS. In conclusion, HCV-positive FL has unique clinical features and may have a great impact on the overall survival of affected patients.

Prognostic factors for histiocytic and dendritic cell neoplasms

Histiocytic and dendritic cell neoplasms are rare and poorly studied. We report the clinical characteristics and prognostic factors in such cases in Japan. We investigated the clinical characteristics and survival in 87 adult patients with histiocytic and dendritic cell neoplasms. Fifty patients had histiocytic sarcoma, 12 had Langerhans cell histiocytosis, 11 had follicular dendritic cell sarcoma, 8 had Langerhans cell sarcoma, 6 had interdigitating cell sarcoma and 1 had indeterminate dendritic cell sarcoma. The median follow-up period was 18.0 (range: 9.6-71.8) months, and median overall survival (OS) was 23.5 months. The 2-year OS rate was 49.2%. In the multivariate analysis, elevated lactate dehydrogenase (LDH) (p =.004), ECOG performance status (PS) 2-4 (p =.006), and Ann Arbor stage III-IV (p =.008) affected OS. Stratification by elevated LDH, ECOG PS 2-4, and Ann Arbor stage III-IV allowed classification of patients into low risk, intermediate risk, and high risk groups. The same classification was applicable for HS and non-HS categories. In the rare neoplasms of histiocytic and dendritic cell sarcoma, ECOG PS, Ann Arbor stage, and LDH are important prognostic factors for predicting survival.

Clinicopathological features of primary splenic follicular lymphoma

Follicular lymphoma (FL) is a low-grade lymphoma that is usually characterized by generalized lymphadenopathy. Extranodal invasion by FL generally involves the bone marrow, skin, and duodenum; splenic infiltration often occurs in the advanced stages. However, primary splenic FL is very rare. Hence, few studies have been performed on splenic FL, and its clinicopathological features have not been established. This study aimed to investigate the clinicopathological features of primary splenic FL, as compared to nodal FL. We analyzed 17 patients diagnosed with primary splenic FL and 153 control patients with systemic FL. Hepatitis C virus (HCV)-positive status was significantly more common in patients with splenic FL than in the control patients (p = 0.02). Ann Arbor stage III or IV (p = 0.0003) and high-risk FLIPI (Follicular Lymphoma International Prognostic Index) (p = 0.03) were significantly less common in patients with splenic FL than in the control patients; however, the overall and progression-free survival curves were not significantly different between the groups. Among the 17 patients with splenic FL, the progression-free survival was significantly worse in patients who underwent splenectomy without receiving postoperative chemotherapy than in those who did (p = 0.03). These results suggest that primary splenic FL should be considered different from systemic FL; accordingly, its management should also be conducted differently.

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.

Clinical features of diffuse large B-cell lymphoma with polyploidy

Polyploidy, defined as more than two sets of homologous chromosomes, is found in a variety of malignant tumors and is thought to be related to disease pathogenesis. However, there have been no studies that have investigated polyploidy in diffuse large B-cell lymphoma (DLBCL). Here we reviewed clinicopathological features of 16 cases of DLBCL with polypoidy, which was defined as DLBCL with either near-tetraploid or greater number of chromosomes as detected by the G-band method. The frequency of polyploid DLBCL was 2.9 % (16/544), including 15 near-tetraploid and one near-pentaploid case. CD5, CD30 and EBER positive cases were 13 % (2/16), 13 % (2/16) and 6 % (1/16), respectively. Bcl2 positive cases were 75 % (12/16). The numbers of huge and multinucleated cells were higher in polyploid than in non-polyploid DLBCL (P = 0.0029 and P < 0.0001, respectively). Clinical features of polyploid DLBCL included reduced infiltration of extranodal sites (2/15, 13 %) and major lymph node infiltration. Of seven cases that received chemotherapy, six responded to treatment and survived. Our results suggest that polyploid DLBCL represents a clinicopathologically characteristic group of DLBCL. This knowledge can be useful for informing more personalized and targeted management of DLBCL patients.

CCR4 frameshift mutation identifies a distinct group of adult T cell leukaemia/lymphoma with poor prognosis

Adult T cell leukaemia/lymphoma (ATLL) is an intractable T cell neoplasm caused by human T cell leukaemia virus type 1. Next-generation sequencing-based comprehensive mutation studies have revealed recurrent somatic CCR4 mutations in ATLL, although clinicopathological findings associated with CCR4 mutations remain to be delineated. In the current study, 184 cases of peripheral T cell lymphoma, including 113 cases of ATLL, were subjected to CCR4 mutation analysis. This sequence analysis identified mutations in 27% (30/113) of cases of ATLL and 9% (4/44) of cases of peripheral T cell lymphoma not otherwise specified. Identified mutations included nonsense (NS) and frameshift (FS) mutations. No significant differences in clinicopathological findings were observed between ATLL cases stratified by presence of CCR4 mutation. All ATLL cases with CCR4 mutations exhibited cell-surface CCR4 positivity. Semi-quantitative CCR4 protein analysis of immunohistochemical sections revealed higher CCR4 expression in cases with NS mutations of CCR4 than in cases with wild-type (WT) CCR4. Furthermore, among ATLL cases, FS mutation was significantly associated with a poor prognosis, compared with NS mutation and WT CCR4. These results suggest that CCR4 mutation is an important determinant of the clinical course in ATLL cases, and that NS and FS mutations of CCR4 behave differently with respect to ATLL pathophysiology.

Prognostic Value of Programmed Death Ligand 1 and Programmed Death 1 Expression in Thymic Carcinoma

PURPOSE

The immune checkpoint of the programmed death 1/programmed death ligand 1 (PD-1/PD-L1) pathway is believed to play an important role in evasion of host antitumor immune surveillance in various malignancies; however, little is known about its role in thymic carcinoma. This study investigated PD-1/PD-L1 expression and its association with clinicopathologic features, the expression of immune-related proteins in tumor-infiltrating lymphocytes (TIL), and patient prognosis.

EXPERIMENTAL DESIGN

PD-L1 and PD-1 expression was evaluated by IHC in 25 thymic carcinoma tissue specimens. Copy number alterations of the PD-L1 gene in 11 cases were assessed in formalin-fixed, paraffin-embedded material using qRT-PCR.

RESULTS

Compared with normal subjects, 3 thymic carcinoma patients showed an increase in PD-L1 copy number, whereas 8 did not. PD-L1 was significantly overexpressed in cases with copy number gain as compared with normal cases. High PD-L1 expression was associated with higher disease-free and overall survival rates as compared to cases with low expression. Prognostic analysis revealed low PD-L1 expression and high number of PD-1(+) TILs as significant predictors of poor survival, together with Masaoka-Koga stage IVa/IVb disease and incomplete resection. In the quantitative analysis of TILs, PD-L1 expression correlated proportionally with the number of infiltrating CTLs.

CONCLUSIONS

Here, for the first time, we report that PD-L1 and PD-1 expression might be useful prognostic predictors in thymic carcinoma. Further studies are expected to substantiate the prognostic value of PD-L1 and PD-1 expression, and the potential efficacy of targeting the PD-1/PD-L1 pathway in thymic carcinoma via immunotherapy. Clin Cancer Res; 22(18); 4727-34. ©2016 AACR.

Weekly nanoparticle albumin-bound paclitaxel(nab-PTX) as second-or later-line treatment for unresectable or recurrent gastric cancer in practice

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Background: Nanoparticle albumin-bound paclitaxel (nab-PTX) is a novel, solvent polyoxyethylated castor oil-free, biologically interactive form of paclitaxel (PTX). Nab-PTX allows shorter infusion schedules and needs no premedication for hypersensitivity reactions, so nab-PTX will be used as the alternative to PTX for more patients. In Japan, nab-PTX was approved as tri-weekly regimen (210mg/m2 every 3weeks) for gastric cancer. On the other hands, weekly PTX (80mg/m2 on day1, 8, and 15, every 4weeks) is mostly used as PTX regimen as 2nd or later line treatment for gastric cancer in Japan. So in practice, nab-PTX would be used by weekly regimen same as weekly PTX. However, the safety and efficacy of weekly nab-PTX for gastric cancer had not been reported yet. Methods: Unresectable or metastatic gastric cancer patients who began receiving weekly nab-PTX as 2nd or later line chemotherapy in our two facilities from February 2013 to August 2014 were retrospectively analyzed for the safety and efficacy. Written informed consent about the treatment of weekly nab-PTX was obtained from all patients before treatment. Results: A total of 32 patients were assessed, retrospectively. The dose and schedule of nab-PTX was 100mg/m2 on day1, 8, and 15, every 4weeks in all patients. Patients characteristics were as follows: median age 67.5(37-84); Male/female: 24/8; PS 0/1/2/3:15/8/7/2; treatment line 2/3/4/5: 12/14/5/1. The overall response rate was 9.3% (CR/PR/SD/PD/NE: 1/2/12/15/2). The median progression-free survival (mPFS) and median overall survival (mOS) were 2.99 months and 5.95 months, in all patients. In 23 patients whose PS were 0 or 1, mPFS and mOS were 4.14 months and 8.44 months. Most common grade 3/4 hematological toxicities were anemia (46.9%), neutropenia (40.6%), febrile neutropenia (15.6%). About the sensory neuropathy, grade 3 was 9.3%, grade2 was 21.9%, and grade1 was 3.1%. There were no treatment-related deaths. Conclusions: Weekly nab-PTX showed promising efficacy against previously treated unresectable or recurrent gastric cancer especially for good PS patients, The Common toxicities of weekly nab-PTX were well-tolerated.

[Acute renal tubular damage caused by disseminated Trichosporon infection in primary myelofibrosis]

A 70-year-old man received a course of therapy that consisted of prednisolone, cyclosporine, and etoposide due to hemophagocytic syndrome which had developed during primary myelofibrosis. He also received micafungin (MCFG) as prophylaxis against a potential fungal infection. We diagnosed febrile neutropenia due to the hemophagocytic syndrome therapy and candidemia because Candida species were detected in blood cultures. He received liposomal amphotericin B (L-AMB) for the candidemia but did not respond to this treatment. Oliguria was diagnosed and renal failure progressed rapidly. We suspected that his renal failure had been induced by the antibiotics. We thus changed the antibiotic regimen but he died of progressive renal failure. We performed renal necropsy and diagnosed acute interstitial tubular nephritis, due to a yeast-like fungus that generally invades the renal tubules. The yeast-like fungus was later identified as Trichosporon asahii, rather than candida, by blood cultures. An immunocompromised host receiving MCFG for acute progressive renal failure requires an appropriate antifungal drug considering the possibility of disseminated Trichosporon.

Hepatitis B virus reactivation with rituximab-containing regimen

Rituximab is recognized as a useful drug for the treatment of B-cell non-Hodgkin’s lymphoma and its use has been extended to such diseases as idiopathic thrombocytopenic purpura, thrombotic thrombocytopenic purpura, chronic rheumatoid arthritis and ANCA-associated vasculitides. One serious complication associated with its use is the reactivation of hepatitis B virus and the search for methods to prevent this occurrence has resulted in the rapid accumulation of knowledge. In this review, we discuss case analyses from our department and other groups and outline the current knowledge on the topic and the remaining issues.

Primary biliary cirrhosis associated with ulcerative colitis

A rare case of concurrent primary biliary cirrhosis and ulcerative colitis is described in a 61 year-old Japanese male. Primary biliary cirrhosis was diagnosed on the basis of characteristic histologic findings and a positive serum mitochondrial antibody test. Ulcerative colitis was diagnosed from typical findings on colonoscopy and the histologic features of a sigmoid colon biopsy specimen. This is the 12th report of a patient presenting with the combination of primary biliary cirrhosis and ulcerative colitis. The potential autoimmune relationships on the basis of these conditions are discussed.

Autoimmune cholangiopathy associated with rheumatoid arthritis

We herein describe a patient with autoimmune cholangiopathy complicated with rheumatoid arthritis. A 58-year-old female was admitted to our hospital due to complications of arthralgia in her fingers, shoulders, elbows, knees and ankles. She presented with abnormally elevated levels of transaminases, alkaline phosphatase and was also negative for hepatitis B virus, hepatitis C virus and the serum mitochondrial antibody test, but had high titers of serum antinuclear antibody, rheumatoid factor and rheumatoid arthritis hemagglutination. A liver biopsy specimen showed chronic non-suppurative destructive cholangitis. She was thus diagnosed to have autoimmune cholangiopathy and rheumatoid arthritis. She began treatment with prednisolone 40 mg per day. After 20 days of steroid therapy, her hepatic function tests improved and the arthralgia symptoms disappeared. This is, to our knowledge, the first case of autoimmune cholangiopathy associated with rheumatoid arthritis, in which both symptoms improved with steroid therapy.

Hepatocellular carcinoma with metastasis to the rib complicated by hemothorax. An autopsy case

A 64-year old man was admitted to our hospital with multiple hepatocellular carcinoma (HCC) lesions in the liver, lung and bone. Three weeks after admission, the patient became complicated with right upper chest pain. A chest radiograph showed a marked increase in right pleural effusion. Thoracentesis demonstrated a hemothorax. Despite treatment with a continuous pleural tap and blood transfusions, the patient's clinical status worsened and he developed severe dyspnea. His right pleural effusion might be considered to be caused by a rupture of the HCC metastasis in the right 2nd rib. The patient died due to respiratory and hepatic failure 26 hours after his occurring the pleural effusion. An autopsy revealed moderately differentiated HCC in the liver, lung and bone. The HCC metastasis of the right 2nd rib was found to have torn the nearby pleura. We described a rare case in which hemothorax was caused by a ruptured rib-based HCC.

Ruptured duodenal varices: an autopsy case report

Bleeding from duodenal varices is a rare and life-threatening complication of cirrhosis. The diagnosis and management of this disease remains problematic. We herein report an autopsy case of a patient who suffered from recurrent bleeding from duodenal varices. A 48 year-old man with cirrhosis presented with upper gastrointestinal bleeding. He had three episodes of massive melena during the 6 months prior to admission. However, the source of bleeding was not known. Emergent endoscopy revealed jet bleeding from varices in the second to third portion of the duodenum. Endoscopic ethanol injection sclerotherapy was attempted but rebleeding occurred and the patient died.

Recurring encephalopathy abolished by gastrorenal shunt ligation in a diabetic hemodialysis patient

A 57-year-old man was admitted to our hospital for hepatic encephalopathy. He previously had undergone a partial gastrectomy for gastric ulcer, and also had been on maintenance hemodialysis because of diabetic nephropathy. Despite treatment with branched-chain amino acids and lactulose, encephalopathy occurred repeatedly. The findings of his laboratory examinations, computed tomography, and liver biopsy were not suggestive of chronic liver damage. Angiography revealed a portal-systemic shunt from the superior mesenteric vein via the left gastric vein to the left renal vein. A ligation of the gastrorenal shunt was performed. After the shunt ligation, hepatic encephalopathy no longer recurred, and no medication was required to prevent it. The insulin requirements also decreased, the plasma ammonia concentration then decreased, and serum concentration of several amino acids related to the ammonia metabolism also decreased. The molar ratio of branched-chain amino acids to aromatic amino acids increased. The ligation of the portal-systemic shunt was thus considered to be the key to the successful treatment of hepatic encephalopathy in this unusual case.

A rare case of hepatic injury associated with ovarian hyperstimulation syndrome

A 26-year-old married woman was admitted to our hospital because of massive ascites and hepatic injury. The patient had been treated with human menopausal gonadotropin and clomiphene citrate to prevent recurrence of spontaneous abortions. About 1 month later, she developed upper abdominal pain and noticed dark urine. On admission, she had elevated concentrations of serum transaminases with an asparate aminotransferase of 127 IU/L and alanine aminotransferase of 194 IU/L. An abdominal ultrasound showed massive ascites. Her serum concentration of estradiol was high at 12,100 pg/mL, which was much greater than the value of early stage of pregnancy (2,279-7,353 pg/mL). She was thus diagnosed as having ovarian hyperstimulation syndrome. Following a period of bed rest, her liver function normalized and the ascites disappeared. Based on the above findings, the patient was considered to have suffered from ovarian hyperstimulation syndrome, complicated by hepatic injury.

[Thyroid function in patients with Yusho: 28 year follow-up study]

To evaluate chronic effect of polychlorinated biphenyl (PCB) on thyroid functions, thyroid hormone levels and thyroidal autoantibodies were studied in 81 patients with Yusho in 1996. Serum level of thyroid stimulating hormone (TSH) was elevated in 7 cases (8.6%). All of them showed normal triiodothyronine (T3), thyroxine (T4) and free T4 levels, and regarded as latent hypothyroidism. There were no significant correlations between blood PCB concentrations and TSH levels, T2 levels, T4 levels or free T4 levels. Thyroglobulin antibodies were detected in 8 cases (19.5%) of 41 Yusho patients with high PBC concentration (higher than 3.0 ppb), and in only one case (2.5%) of 40 patients with low PBC concentration (lower than 2.9 ppb). We conclude that thyroglobulin antibody in patients with Yusho is not frequent and it may be associated with blood PCB concentration.