We demonstrated that the number of circulating pDCs is low in patients with primary and H. pylori-associated ITP and that it changes depending on treatment modality. Further investigation is warranted with regard to the role of pDCs in the immunopathogenesis of ITP.

SummaryThere have been conflicting reports over the JAK2-V617F mutation status of platelets in chronic myeloproliferative diseases (CMPDs). The aim of this study was to analyse JAK2-V617F status, not only in granulocytes but also in platelets. The JAK2-V617F mutation was analysed in both granulocytes and platelets in 115 patients with CMPDs using direct sequencing. JAK2-V617F was detected in granulocytes from 71 of those patients, all 71 of whom also had platelet JAK2-V617F expression. The remaining 44 patients showed negative JAK2-V617F expression on granulocytes, but positive JAK2-V617F expression was detected on the platelets from nine of the 33 essential thrombocythaemia (ET) patients, one of the eight polycythaemia vera patients, and two of the three primary myelofibrosis patients. When ET patients were divided into three groups according to granulocyte and platelet JAK2-V617F status (both-positive, platelets-only positive and both-negative), the both-positive and platelets-only positive groups shared the clinical features of higher white blood cell count and frequent thrombosis. These results suggest that analysis of platelets is a more sensitive approach for detecting JAK2-V617F in CMPD patients than analysis of granulocytes. They also suggest that previous reports of the incidence of JAK2-V617F in CMPD patients, obtained using only analysis of granulocytes, could be underestimations.

Objective While the somatic mutation of Janus Kinase 2 (JAK2) and the thrombopoietin receptor (c-MPL) gene are thought to affect the pathogenesis of bcr/abl negative chronic myeloproliferative neoplasm (MPN), the relationship between the mutation and the clinical features remain obscure. Methods The mutation status of these genes in granulocytes, platelets, T-cells, and erythroid colonies (BFU-E) was obtained from 115 MPN patients, and then the clinical features of the MPN subtypes were compared. Results The JAK2-V617F mutation was observed in three lineages of granulocytes, platelets, and BFU-E in almost all polycythemia vera (PV) and primary myelofibrosis (PMF) patients. In contrast, 68% of essential thrombocythemia (ET) patients have the JAK2-V617F mutation in at least one of the lineages, of which 70% of these patients have the JAK2-V617F mutation in three lineages; the remaining ET patients with the JAK2-V617F mutation only exhibited the mutation in one or two lineages. Further, the ET patients that exhibited the JAK2-V617F mutation in three lineages had higher WBC and granulocyte counts as compared to the ET patients that did not have the JAK2-V617F mutation or only had the mutation in one or two lineages. Concerning the MPL gene, two ET patients had the MPL-W515L gene mutation in their platelets, although the lineage of the JAK2-V617F mutation involved differed from case to case. Conclusion The progenitor cells that are involved with the JAK2-V617F mutation in MPNs are different in each subtype and this difference may also affect the clinical features of MPNs.

90Y-ibritumomab tiuxetan (90Y-IT) is widely used, but the factors responsible for its optimal treatment effects are unknown. We enrolled 34 patients with relapsed indolent lymphoma treated with 90Y-IT monotherapy at Gunma University Hospital between 2003 and 2014 in the present study. Clinical data including computed tomography and 18-Fluoro-deoxyglucose positron emission tomography were retrospectively analyzed. The overall response rate and complete response rate were 91% and 82%, respectively. The median progression-free survival (PFS) and overall survival were 32 months and not reached, respectively. In univariate analysis, tumor long-axis diameter ≤ 2.5 cm, maximum standardized uptake value (SUVmax) ≤ 6.5, localized disease, normal levels of serum soluble interleukin-2 receptor, and the number of involved nodal sites ≤ 3 immediately prior to 90Y-IT were associated with median PFS greater than 6 years. However, in multivariate analysis, only tumor long-axis diameter ≤ 2.5 cm and SUVmax ≤ 6.5 affected PFS [hazard ratio (HR) 0.130, P = 0.0021 and HR 0.283, P = 0.0311, respectively]. Patients with only one prior regimen needed less granulocyte colony-stimulating factor and platelet transfusion. Thus, 90Y-IT treatment should be considered for patients with indolent lymphoma in first relapse who have tumor long-axis diameter ≤ 2.5 cm and SUVmax ≤ 6.5.

We evaluated the prognostic significance of the serum level of the soluble form of interleukin-2 receptorα (sIL-2Rα) and investigated its association with CD25 expression on tumor cells in diffuse large B-cell lymphoma (DLBCL). Three hundred and thirty-eight adult patients with newly diagnosed DLBCL were eligible for this retrospective study. 32.2% of patients were treated with CHOP-like regimen and 67.8% with R-CHOP-like regimen. CD25 expression on the surface of tumor cells was evaluated in 143 cases and its relationship with sIL-2Rα level was also investigated. Both overall survival (OS) and progression-free survival (PFS) were poorer in patients with higher sIL-2Rα, in both R-CHOP and CHOP groups. sIL-2Rα > 1,000 U/mL and performance status (PS) ≥ 2 were independently associated with poorer OS, and sIL-2Rα > 1,000 U/mL, age > 60 years, and ≥ 2 extranodal sites were independently associated with poorer PFS in the R-CHOP group. The sIL-2Rα level was higher in the CD25-positive group than in the CD25-negative group in stage 3 or 4 disease (p = 0.010). Multiple linear regression analysis showed CD25 expression to be independently correlated with sIL-2Rα levels. High sIL-2Rα is an important risk factor for survival in DLBCL treated with not only CHOP-like, but also R-CHOP-like regimens, regardless of the tumor's expression of CD25.