Taiki Sato

MYD88 (L265P) mutation is associated with an unfavourable outcome of primary central nervous system lymphoma.

Primary central nervous system lymphomas (PCNSL) are rare forms of diffuse large B cell lymphoma (DLBCL) that arise within the brain or the eyes. The current molecular classification of DLBCL distinguishes two main subtypes: activated B-cell-like (ABC)-lymphoma and germinal centre B-cell-like (GCB)-lymphoma (Zhang et al, 2013). PCNSL typically show an immunophenotype resembling that of ABC-DLBCL (Zhang et al, 2013). Somatic mutations in the myeloid differentiation primary response gene 88. (MYD88), CD79b molecule, immunoglobulin-associated beta (CD79B) and caspase recruitment domain family, member 11 (CARD11) genes were recently shown to control cell survival of ABC-DLBCL by promoting the nuclear factor (NF)jB signalling pathway (Zhang et al, 2013). The mutation frequencies of MYD88, CD79B and CARD11 are 15–30%, 17–23% and 8–18% in ABC-DLBCL (Zhang et al, 2013) and are reported to be 40–79%, 30~-44% and 11–30% in PCNSL, Indicating that they are strongly over-represented in PCNSL (Braggio et al, 2015; Yamada et al, 2015). In addition, several other gene mutations were more prevalent in PCNSL than in DLBCL, not otherwise specified; “pim-1 oncogene” (PIM1: 20–44%), “transducin (beta)-like 1 X-linked receptor 1” (TBL1XR1: 7–23%), “BTG family, member 2” (BTG2: 22– 30%), “PR domain containing 1, with ZNF domain” (PRDM1: 7–20%) and “tumor necrosis factor, alpha-induced protein 3” (TNFAIP3: 11–20%) (Braggio et al, 2015). Nonetheless, the clinical relevance of these mutations remains unclear, although several specific clinical parameters may predict the treatment outcome of PCNSL patients. These include altered mental activity and elevated creatinine clearance (CrCl) (Taoka et al, 2010); age >50 years and Karnofsky performance score <70 (Memorial Sloan-Kettering Cancer Center prognostic score; Abrey et al, 2006); age >75 years, increased serum lactate dehydrogenase level, cerebrospinal fluid protein concentration and lymphoma involvement of deep brain structures (International Extranodal Lymphoma Study Group prognostic scoring system; Abrey et al, 2006), were identified as prognostic factors. However, recent advances in genetic knowledge are not incorporated in any of these proposals. Hence, we conducted this study to elucidate the impact of gene mutations on clinical outcome of PCNSL. We analysed 42 human immunodeficiency virus (HIV)negative PCNSL patients who were treated with a modified version of the European Organization for Research and Treatment of Cancer protocol (Taoka et al, 2010) at the University of Tsukuba Hospital between March 2005 and May 2015. This protocol consisted of intermediate-dose methotrexate (MTX), lomustine, procarbazine, methylprednisolone and intrathecal chemotherapy with MTX and cytarabine (Table SI) (Taoka et al, 2010). All PCNSL patients in this study had DLBCL. GCB and ABC phenotypes were assessed by immunohistochemistory using anti-CD10, MUM1 and BCL6 antibodies. Targeted deep sequencing was performed by using Ion Ampliseq technology (Methods S1, Table SII). Clinical parameters were collected from the clinical record (Methods S1). Overall survival (OS) and progression-free survival (PFS) were estimated using the KaplanMeier method and compared by the Peto-Peto generalized Wilcoxon test. All data were analysed with EZR (http://www. jichi.ac.jp/saitama-sct/SaitamaHP.files/statmedEN.html). Multivariate analysis was performed with Cox regression model. Significance was set at P ≤ 0 05. The major clinical characteristics of the 42 patients are summarized in Table SIII. At least one mutation was detected in 38 out of 42 cases (90 4%). Notably, we found recurrent mutations in MYD88 (67%), CD79B (43%), PIM1 (69%), TBL1XR1 (24%), BTG2 (29%), PRDM1 (24%) and TNFAIP3 (12%) (Table SIV, Fig. S1) at frequencies similar to those previously reported (Braggio et al, 2015; Yamada et al, 2015). For the entire cohort, the median follow-up time was 26 months (range, 1–105 months), with 3-years OS and PFS of 46% and 26%, respectively, comparable to the survival rate of our previous cohort treated with the same protocol (Taoka et al, 2010). Univariate analysis showed that age >75 years (P = 0 0105) and altered mental activity (P = 0 0202) (Table SV) were significantly associated with inferior OS. In addition, MYD88 L265P mutation (P = 0 127, Fig. 1A), CrCl >90 ml/min (P = 0 124) and deep brain involvement (P = 0 0649) showed a tendency to be associated with inferior OS, although statistically non-significant (Table SV). When adjusted in a multivariate Cox regression analysis, MYD88 L265P mutation remained as a significant risk factor for death (hazard ratio (HR), 2 903; 95% confidence interval (CI), 1 013–8 323, P = 0 0474), together with altered mental activity (HR, 4 729; 95% CI, 1 522–14 7, P = 0 0072) (Table I). Regarding PFS, CrCl >90 ml/min (P = 0 0286) and altered mental activity (P = 0 0473) were significant factors for inferior PFS (Table SV). MYD88 L265P mutation (P = 0 0872, Fig. 1B) was not significantly associated, but showed a tendency to be

DNMT3a expression pattern and its prognostic value in lung adenocarcinoma.

OBJECTIVES DNA methyltransferases (DNMTs) are an important part of the methylation pathway that is highly correlated with the pathophysiology of cancers. Several studies have reported overexpression of DNMTs in human lung cancer, but none have compared the expression pattern to pathological features. In this study, we clarified the association of DNMT3a expression pattern with pathological features and prognosis of lung adenocarcinoma. MATERIALS AND METHODS 135 cases of surgically resected lung adenocarcinoma specimens were used for DNMT3a immunohistochemistry (IHC). IHC score was determined by counting the number of positive nuclei. The ROC curve was drawn to determine the best cut-off point of the score; this was set at 57.5. Western blot also implemented and confirmed the specificity of the antibody. Correlations between expression pattern and clinicopathological features and prognosis were analyzed using chi-squared method and Cox proportional hazards model respectively. RESULT Seventy-nine of the 135 cases (58.5%) showed strong positive reactivity to anti-DNMT3a. In terms of histological subtypes, among invasive lung adenocarcinomas 41 out of 53 lepidic adenocarcinomas (77%) were strongly positive, while among the other histological subtypes only 23 out of 66 cases (34.8%) showed a positive reaction. Among non-invasive lung adenocarcinomas 15 out of 16 cases (93.8%) were strongly positive. The level of DNMT3a expression was associated with patient outcome, and patients with weak expression of DNMT3a had a poorer outcome than those with strong expression. Multivariate analysis also indicated that DNMT3a is an independent prognostic marker in lung adenocarcinoma. CONCLUSION Our results indicate that DNMT3a expression in lung adenocarcinoma is associated with the histologically non-invasive type and lepidic subtype, and a favorable prognosis. We also showed that DNMT3a expression is an independent prognostic marker in lung adenocarcinoma. Since lack of DNMT3a is thought to facilitate tumor progression, DNMT3a might be clinically applicable as an indicator of favorable prognosis.

miR-3941: A novel microRNA that controls IGBP1 expression and is associated with malignant progression of lung adenocarcinoma

Immunoglobulin (CD79a) binding protein 1 (IGBP1) is universally overexpressed in lung adenocarcinoma and exerts an anti‐apoptotic effect by binding to PP2Ac. However, the molecular mechanism of IGBP1 overexpression is still unclear. In the present study, we used a microRNA (miRNA) array and TargetScan Human software to detect IGBP1‐related miRNAs that regulate IGBP1 expression. The miRNA array analysis revealed more than 100 miRNAs that are dysregulated in early invasive adenocarcinoma. On the other hand, in silico analysis using TargetScan Human revealed 79 miRNAs that are associated with IGBP1 protein expression. Among the miRNAs selected by miRNA array analysis, six (miR‐34b, miR‐138, miR‐374a, miR‐374b, miR‐1909, miR‐3941) were also included among those selected by TargetScan analysis. Real‐time reverse transcription PCR (real‐time RT‐PCR) showed that the six microRNAs were downregulated in invasive adenocarcinoma (IGBP1+) relative to adjacent normal lung tissue (IGBP1−). Among these microRNAs, only miR‐34b and miR‐3941 depressed luciferase activity by targeting 3′UTR‐IGBP1 in the luciferase vector. We transfected miR‐34b and miR‐3941 into lung adenocarcinoma cell lines (A549, PC‐9), and both of them suppressed IGBP1 expression and cell proliferation. Moreover, the transfected miR‐34b and miR‐3941 induced apoptosis of a lung adenocarcinoma cell line, similarly to the effect of siIGBP1 RNA. As well as miR‐34b, we found that miR‐3941 targeted IGBP1 specifically and was able to exclusively downregulate IGBP1 expression. These findings indicate that suppression of miR‐3941 has an important role in the progression of lung adenocarcinoma at an early stage.

Collagenous sprue diagnosed by double balloon endoscopy

Double balloon endoscopy (DBE) is useful for diagnosing many intestinal diseases and for endoscopic procedures. We report a case of chronic diarrhea in a 58‐year‐old Japanese man. He was initially suspected to have malabsorption syndrome. DBE showed reduction of folds, scalloping, mucosal nodularity and granularity. Pathological examinations of biopsies from the jejunum showed severe villous atrophy with subepithelial collagen bands. These findings led to the final diagnosis of collagenous sprue (CS). With1 month of total parenteral nutrition followed by a low‐gluten diet, his symptoms gradually improved. CS has never been reported before in Japan. DBE is useful for making a diagnosis of CS, and may be considered for patients who are suffering from diarrhea of unknown cause.

Blastic plasmacytoid dendritic cell neoplasm arising from clonal hematopoiesis

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare subtype of myeloid neoplasm. Clonal evolution in the development of BPDCN remains to be elucidated. In the present study, we examined clonal evolution in a case of BPDCN by analyzing the distribution of gene mutations in tumor cells and non-tumor blood cells. The p.D1129fs and p.K1005fs TET2 mutations, p.P95H SRSF2 mutation, and p.L287fs NPM1 mutation were identified in a skin tumor at diagnosis and peripheral blood mononuclear cells at relapse. Notably, the p.D1129fs TET2 and p.L287fs NPM1 mutations were observed only in tumor cells, while the p.K1005fs TET2 and p.P95H SRSF2 mutations were found in both tumor cells and non-tumor blood cells. Recent genetic studies have suggested that some blood cancers may originate from clonal hematopoiesis, harboring somatic mutations. In the present case, the data suggest that BPDCN originated from clonal hematopoiesis with the p.K1005fs TET2 and p.P95H SRSF2 mutations via acquisition of the additional p.D1129fs TET2 and p.L287fs NPM1 mutations.

Chronic Graft-versus-host Disease Presenting with Multiple Punctate Intracranial Lesions on Contrast-enhanced Magnetic Resonance Imaging

Central nervous system graft-versus-host disease can present quite a diagnostic challenge. We herein present a case of histologically-confirmed chronic graft versus host disease (GVHD) involving the central nervous system that occurred at 19 months after peripheral blood stem cell transplantation. Cranial magnetic resonance imaging showed areas of confluent hyperintensity in the deep/subcortical white matter with multiple punctate and curvilinear gadolinium enhancements, suggesting the disruption of the blood-brain barrier. A brain biopsy revealed perivascular CD3-positive T cell infiltration around the small vessels. We propose that the detection of punctate-enhanced lesions by magnetic resonance imaging may be a useful finding that facilitates the early diagnosis of chronic GVHD involving the central nervous system.

Late occurrence of Epstein-Barr virus-associated lymphoproliferative disorder in a patient with follicular lymphoma treated with bendamustine and rituximab.

Dear Editor, Combination of bendamustine plus rituximab (BR) has become one of the standard regimens for patients with low-grade lymphomas. In several randomized clinical trials that established the efficacy and safety of BR [1, 2], infectious episodes in patients given with BR were comparable to or less frequent than those with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) [1], or rituximab plus cyclophosphamide, vincristine, and prednisone (R-CVP) [2]. However, several papers emphasize the immunosuppressive effects of bendamustine that increase the risk of opportunistic infections [3–5]. Reactivation of cytomegalovirus has been observed in up to 20 % of those treated with bendamustine-containing chemotherapies [4, 5]. Late occurrence of progressive multifocal leukoencephalopathy (PML) by JC virus was also described [6], although the other drugs combined with bendamustine may also contribute to the immunosuppressive state of these patients. Here, we present a patient who developed Epstein-Barr virus (EBV)-associated lymphoproliferative disorder. A 62-year-old woman was referred to our hospital in 2013 because of right-sided enlargement of the tonsil. Pathological examination of the tonsil showed marked proliferation of smallor medium-sized centrocytes and centroblasts, expressing CD10, CD20, CD79a, BCL2, and BCL6 with follicle-like architecture. A diagnosis of follicular lymphoma, grade2A, stage IIIA was given based on F-FDG PET/CT scan and bone marrow examination. She received 6 cycles of BR; 2 months after the completion, CT scan showed complete remission. Fourteen months after the chemotherapy, she noticed lymphadenopathy in the right cervix and the right axilla. F-FDG PET/CTscan showed glucose uptake on the bilateral cervical and the right axillary lymph nodes. Pathological examination of the right axillary lymph node showed almost preserved architecture with follicular enlargement (Fig. 1a). Also, BCL2-positive cells were restricted to the interfollicular area (Fig. 1b), and scattered CD30-positive large cells were present in the same area (Fig. 1c). Epstein-Barr encoding region (EBER) in situ hybridization revealed that EBV-infected cells were scattered in both the interfollicular area and germinal center, resembling early lesions of post-transplant lymphoproliferative disorder (PTLD) (Fig. 1d). Quantitative analysis of EBV load using a real-time PCR assay detected 1069 copies per microgram DNA in peripheral blood mononuclear cells. Hence, we concluded that she developed EBVassociated lymphoproliferative disorder (LPD), which was attributable to the immunosuppressive state as a result of BR therapy. * Shigeru Chiba schiba-t@md.tsukuba.ac.jp

Mixed Germ Cell Tumor with Extensive Yolk Sac Tumor Elements in the Frontal Lobe of an Adult

Intracranial nongerminomatous germ cell tumors (NGGCTs) in unusual locations are extremely rare. Here, we report a case of a yolk sac tumor in the frontal lobe in a middle-aged patient. A 42-year-old man was admitted to our hospital for headache and nausea. Magnetic resonance imaging (MRI) showed an enhanced mass lesion with a marked cyst component. The serum alpha-fetoprotein (αFP) level was extremely high. Histological examination of specimens after subtotal removal revealed a primary mixed germ cell tumor with extensive yolk sac tumor elements, often referred to as an intracranial “yolk sac tumor.” The preoperative diagnosis of NGGCTs in unusual age and locations is extremely difficult. Clinicians should consider the possibility of NGGCTs, including yolk sac tumors, when intracranial tumors with unusual MRI findings are encountered.

Late-onset Transthyretin (TTR)-familial Amyloid Polyneuropathy (FAP) with a Long Disease Duration from Non-endemic Areas in Japan

We herein report the case of an 84-year-old woman with transthyretin (TTR) Val30Met-associated familial amyloid polyneuropathy (FAP-ATTR Val30Met), representing a very old case. The patient had muscle weakness and sensory disturbances in her extremities caused by severe peripheral neuropathy. She also had vitreous opacity and orthostatic hypotension, and pyrophosphate scintigraphy showed a myocardial accumulation. Esophagogastroduodenoscopy revealed mucosal amyloid deposits, positive in anti-TTR antibody staining. A TTR gene analysis isolated the Val30Met mutation. More than a few cases of FAP-ATTR develop late, like our own, and their familial histories are often obscure in non-endemic areas, which might make a diagnosis difficult.

A Rare Coexistence of Pheochromocytoma and Parkinson's Disease With Diagnostic Challenges : A Case Report

We herein report a case of pheochromocytoma occurring in the course of Parkinsons disease. The coexistence of these two disease is extremely rare, with only four cases hitherto reported across the public databases. It is also noteworthy that biochemical tests, which are critical for the diagnosis of pheochromocytoma, are severely confounded by dopaminergic medications for Parkinsons disease, highlighting the importance of image-based modalities in this setting. We further attempted to gain insight into the potential molecular mechanisms, proposing that hypoxia-inducible factor signaling could make these two diseases mutually exclusive, while excessive reactive oxygen species could enable their coexistence.