Norifumi Tsukamoto

Ki-67 is a strong predictor of central nervous system relapse in patients with mantle cell lymphoma (MCL)

BACKGROUNDnCentral nervous system (CNS) relapse is an uncommon but challenging complication in patients with mantle cell lymphoma (MCL). Survival after CNS relapse is extremely poor. Identification of high-risk populations is therefore critical in determining patients who might be candidates for a prophylactic approach.nnnPATIENTS AND METHODSnA total of 608 patients (median age, 67 years; range 22-92) with MCL newly diagnosed between 1994 and 2012 were evaluated. Pretreatment characteristics and treatment regimens were evaluated for their association with CNS relapse by competing risk regression analysis.nnnRESULTSnNone of the patients received intrathecal prophylaxis. Overall, 33 patients (5.4%) experienced CNS relapse during a median follow-up of 42.7 months. Median time from diagnosis to CNS relapse was 20.3 months (range: 2.2-141.3 months). Three-year cumulative incidence of CNS relapse was 5.6% [95% confidence interval (95% CI) 3.7% to 8.0%]. Univariate analysis revealed several risk factors including blastoid variant, leukemic presentation, high-risk MCL International Prognostic Index and high Ki-67 (proliferation marker). Multivariate analyses revealed that Ki-67 ≥ 30 was the only significant risk factor for CNS relapse (hazard ratio: 6.0, 95% CI 1.9-19.4, P = 0.003). Two-year cumulative incidence of CNS relapse in patients with Ki-67 ≥ 30 was 25.4% (95% CI 13.5-39.1), while that in the patients with Ki-67 < 30 was 1.6% (95% CI 0.4-4.2). None of the treatment modalities, including rituximab, high-dose cytarabine, high-dose methotrexate or consolidative autologous stem-cell transplant, were associated with a lower incidence of CNS relapse. Survival after CNS relapse was poor, with median survival time of 8.3 months. There was no significant difference in the survival by the site of CNS involvement.

Biological significance of fluorine-18- α -methyltyrosine (FAMT) uptake on PET in patients with oesophageal cancer

Purpose:18F-FAMT as an amino-acid tracer for positron emission tomography (PET) is useful for detecting human neoplasms. 18F-FAMT is accumulated in tumour cells solely via L-type amino-acid transporter 1 (LAT1). This study was conducted to investigate the biological significance of 18F-FAMT uptake in patients with oesophageal cancer.Methods:From April 2008 to December 2011, 42 patients with oesophageal cancer underwent both 18F-FAMT PET/CT and 18F-FDG PET/CT before surgical treatment. The immunohistochemical analysis of LAT1, CD98, Ki-67, CD34, p53, p-Akt and p-mTOR was performed on the primary lesions. In vitro experiments were performed to examine the mechanism of 18F-FAMT uptake.Results:High uptake of 18F-FAMT was significantly associated with advanced stage, lymph node metastasis and the expression of LAT1, CD98, Ki-67 and CD34. LAT1 expression yielded a statistically significant correlation with CD98 expression, cell proliferation, angiogenesis and glucose metabolism. In vitro experiments revealed that 18F-FAMT was specifically transported by LAT1.Conclusions:The uptake of 18F-FAMT within tumour cells is determined by the LAT1 expression and correlated with cell proliferation and angiogenesis in oesophageal cancer. The present experiments also confirmed the presence of LAT1 as an underlying mechanism of 18F-FAMT accumulation.

A new staging system to predict prognosis of patients with multiple myeloma in an era of novel therapeutic agents

Various prognostic markers for multiple myeloma (MM) have been identified, and stratification using these markers is considered important to optimize treatment strategies. The international staging system (ISS) is now a widely accepted prognostic staging system for MM patients; however, its validity is controversial in the era of new therapeutic regimens, since ISS had been established before introduction of new agents. We retrospectively reviewed prognostic factors in order to seek out an alternative staging system more suitably applied to MM patients treated with novel agents. We analyzed 178 newly diagnosed MM patients who received either conventional chemotherapy without novel agents (CT; n = 79) or chemotherapy with novel agents (NT; n = 99). Although median overall survival (OS) of patients treated with CT is significantly different depending on stages of ISS, ISS had no effect on OS among patients treated with NT. Meanwhile, we identified hemoglobin (Hb) and plasmacytoma as independent risk factors for OS in patients who received NT. Using these two parameters, we stratified NT patients into three stages; stage 1 (Hb≥10 g/dL and absence of plasmacytoma), stage 2 (not stage 1 or 3), and stage 3 (Hb <10 g/dL and presence of plasmacytoma). We found that there were significant differences in median OS among the three stages (8.13, 5.95, and 2.45 yr for stages 1, 2, and 3, respectively). This preliminary study suggests that this alternative staging system based on Hb and plasmacytoma is a simple and useful way to predict prognosis of MM patients in the novel agent era.

Characterization of CD56+ dendritic-like cells: a normal counterpart of blastic plasmacytoid dendritic cell neoplasm?

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematological malignancy. Plasmacytoid DCs (pDCs), which are defined as lineage marker (Lin)−HLA−DR+CD56−CD123+CD11c− cells, are considered to be the normal counterpart of BPDCNs. However, BPDCN can be distinguished from pDCs by uniform expression of CD56. In this study, to identify a normal counterpart of BPDCN, we searched for a Lin−HLA−DR+CD56+ population and focused on a minor subpopulation of Lin−DR+CD56+CD123+CD11c− cells that we designated as pDC-like cells (pDLCs). pDLC constituted 0.03% of peripheral blood mononuclear cells (PBMCs), and the pDLC/pDC ratio was higher in bone marrow cells than in PBMCs. pDLC clearly expressed BDCA2, BDCA4, and myeloid antigens, which are frequently expressed by BPDCN. pDLCs exhibited modest expression of Toll-like receptors and produced less interferon-α after CpG stimulation, but presented very low endocytic ability unlike mDCs. These functional differences were attributed to the expression profile of transcriptional factors. After in vitro culture with Flt3-ligand and GM-CSF, pDLCs expressed CD11c and BDCA1. These data suggested that pDLCs are a distinct subpopulation, with an immunophenotype similar to BPDCNs. Moreover, our results indicate that pDLCs might be immature DCs and might contribute to the immunophenotypical diversity of BPDCNs.

Gene polymorphisms of mannose-binding lectin confer susceptibility to Pneumocystis pneumonia in HIV-infected patients.

BACKGROUNDnMannose-binding lectin (MBL) plays an important role in innate immunity. The aim of this study was to determine whether genetic variants of MBL confer susceptibility to Pneumocystis pneumonia (PCP) in patients with advanced human immunodeficiency virus (HIV) infections.nnnOBJECTIVEnHIV patients (n = 53) having CD4 counts <200/μL who were admitted to our hospital were analyzed. Of these 53 patients, 30 had PCP at admission, and 23 did not. Genotypes at six single nucleotide polymorphisms (SNP) in MBL2 gene and serum MBL levels were determined for each patient, and compared between patients with or without PCP. We also examined whether MBL enhances phagocytosis of macrophages against rat-type Pneumocystis organism in vitro.nnnRESULTSnGenotypes associated with low production of MBL were significantly more common in the PCP group than in the non-PCP group (P = 0.049, odds ratio 2.17, 95% CI 1.02-4.63). Serum MBL levels were significantly higher in the non-PCP group (P = 0.039). Findings from in vitro experiments indicated that MBL act as a direct opsonin enhancing macrophage-mediated phagocytosis of Pneumocystis organisms.nnnCONCLUSIONnGenetic variation of MBL production influences susceptibility to PCP in patients with advanced HIV infection, and can be regarded as a risk factor for PCP.

CD98 as a novel prognostic indicator for patients with stage III/IV hypopharyngeal squamous cell carcinoma

Both L‐type amino acid transporter 1 (LAT1) and CD98 are strongly expressed in primary human cancer and play essential roles in tumor growth. We studied the clinicopathological significance of LAT1 and CD98 expression in hypopharyngeal squamous cell carcinoma (SCC).

Development of IgG4-related disease 10 years after chemotherapy for diffuse large B cell lymphoma and longstanding bronchial asthma

Reported is a rare case IgG4-related disease that developed 10xa0years after combination chemotherapy for non-Hodgkin lymphoma. A 59-year-old Japanese man with longstanding bronchial asthma was referred to our hospital for bilateral hilar lymph node enlargement. The initial diagnosis was diffuse large B cell lymphoma (DLBCL) by supraclavicular lymph node biopsy. Serum IgG was high (4550xa0mg/dL) at diagnosis. The patient achieved complete response following six cycles of combination chemotherapy. Ten years later, bilateral submaxillary gland swelling was observed. Serum IgG and IgG4 were 2909 and 1470xa0mg/dL, respectively. The patient was diagnosed with IgG4-related disease by submandibular lymph node biopsy. Due to the difficulty in distinguishing IgG4-related disease from DLBCL through imaging findings alone, pathological confirmation of such lesions by biopsy is mandatory before proceeding to treatment.

SF3B1 and IGHV gene mutation status predict poor prognosis in Japanese CLL patients

The incidence of chronic lymphocytic leukemia (CLL) is low in Japan. The clinical course ranges from very indolent to rapidly progressive. Recently, several reports have indicated that mutation of the splicing factor 3b, subunit 1 (SF3B1) gene in CLL is predictive of a poor prognosis. Here, we investigated the SF3B1 mutational status of Japanese CLL patients and clarified the association between SF3B1 mutational status and prognostic factors. One hundred and two patients that were referred to our institutions between 1999 and 2013 were enrolled. Mutation analysis of SF3B1 (nxa0=xa087) and of the immunoglobulin heavy chain gene (IGHV) (nxa0=xa0102) was performed at diagnosis. FISH analysis of del(11)(q22) was performed for 17 patients. Seven patients have SF3B1 mutation (8.0xa0%: K700E, 5/7; G742D, 1/7 and Y623C, 1/7). The median survival times for patients with mutated and non-mutated SF3B1 were 53 and 130xa0months, respectively. Overall survival of the mutated SF3B1 group was significantly lower than that of the non-mutated group (pxa0=xa00.0187). No relationship was observed between IGHV mutational status and SF3B1 mutation. There was no patient with SF3B1 mutation in the IGHV1-69 population (0/2). In conclusion, mutation of SF3B1 at diagnosis in Japanese CLL patients is predictive of a poor prognosis.