Annalisa Andreoli

Efficacy and safety of pegylated-interferon α-2a in myelofibrosis: a study by the FIM and GEM French cooperative groups.

Myeloproliferative neoplasm‐related myelofibrosis is associated with cytopenic or proliferative phases, splenomegaly and constitutional symptoms. Few effective treatments are available and small series suggested that interferon could be an option for myelofibrosis therapy. We performed a retrospective study of pegylated‐interferon α‐2a (Peg‐IFNα‐2a) therapy in myelofibrosis. Sixty‐two patients treated with Peg‐IFNα‐2a at 17 French and Belgian centres were included. Responses were determined based on the criteria established by the International Working Group for Myelofibrosis Research and Treatment. Mean follow‐up was 26 months. Sixteen of 25 anaemic patients (64%) (eight concomitantly receiving recombinant erythropoietin) achieved a complete response and transfusion‐independence was obtained in 5/13 patients (38·5%). Constitutional symptoms resolved in 82% of patients. All five leucopenic patients normalized their leucocyte counts, whereas a normal platelet count was obtained in 5/8 thrombocytopenic patients. Splenomegaly was reduced in 46·5% of patients, and complete resolution of thrombocytosis and leucocytosis were observed in 82·8% and 68·8% of patients, respectively. Side effects (mostly haematological) were mainly of grade 1–2. The only factor independently associated with treatment failure was a spleen enlargement of more than 6 cm below the costal margin. In conclusion, Peg‐IFNα‐2a induced high response rates with acceptable toxicity in a large proportion of patients with primary and secondary myelofibrosis, especially in early phases.

The impact of P53 and P21(waf1) expression on the survival of patients with the germinal center phenotype of diffuse large B-cell lymphoma

Purpose: To prospectively investigate the prognostic significance of p21 and p53 expression in diffuse large B-cell lymphoma in the context of the U.S. Intergroup trial comparing conventional cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy to rituximab-CHOP (R-CHOP) induction, with or without maintenance rituximab. Experimental Design: Immunohistochemical staining of 197 paraffin-embedded biopsy specimens was scored by an independent panel of experts. Results: The cyclin-dependent kinase inhibitor, p21, was expressed in 55% of cases examined. In a multivariable analysis adjusting for International Prognostic Index score and BCL2 status, p21 expression was a significant, independent, favorable predictive factor for failure-free survival (relative risk, 0.3; P = 0.001) and overall survival (relative risk, 0.3; P = 0.003) for patients treated with R-CHOP. Expression of p21 was not predictive of outcome for CHOP-treated patients. Only p21-positive cases benefited from the addition of rituximab to CHOP. Among p21-positive patients, treatment with R-CHOP was associated with a higher failure-free survival rate at 5 years compared with CHOP (61% versus 24%; P = 0.01). In contrast, no significant differences were detected in failure-free survival according to treatment arm for p21-negative patients. Expression of p53, alone or in combination with p21, did not predict for outcome in univariable or multivariable analyses. Conclusions: In this study, p21 protein expression emerged as an important independent predictor of a favorable clinical outcome when rituximab was added to CHOP therapy. These data suggest that rituximab-related effects on lymphoma survival pathways may be functionally linked to p21 activity. Clin Cancer Res; 16(8); 2435–42. ©2010 AACR.Immunohistochemically detected over-expression of P53-related protein (P53+++) and absence of P21(waf1) expression (P21-) correspond to loss of function of the P53-gene in diffuse large B-cell lymphoma (DLBCL) patients. Using immunohistochemistry we examined 80 patients with DLBCL and found that 23% had the P53+++/P21- phenotype while 51% had a germinal center (GC) pattern. Both the P53+++/P21- phenotype and the non-GC pattern were associated with inferior outcome. Notably, the prognostic power of the P53+++/P21- phenotype was restricted to patients with a GC pattern, without effect on outcome of patients with a non-GC phenotype. Our results show that immunohistochemistry can parallel gene expression profiling in addressing clinical variability of DLBCL patients.

Selective testing for calreticulin gene mutations in patients with splanchnic vein thrombosis: A prospective cohort study

BACKGROUND AND AIMS Myeloproliferative neoplasms (MPN) are the leading cause of splanchnic vein thrombosis (SVT). Janus kinase 2 gene (JAK2)V617F mutations are found in 80 to 90% of patients with SVT and MPN. Mutations of the calreticulin (CALR) gene have also been reported. However, as their prevalence ranges from 0 to 2%, the utility of routine testing is questionable. This study aimed to identify a group of patients with SVT at high risk of harboring CALR mutations and thus requiring this genetic testing. METHODS CALR, JAK2V617F and thrombopoietin receptor gene (MPL) mutations were analysed in a test cohort that included 312 patients with SVT. Criteria to identify patients at high risk of CALR mutations in this test cohort was used and evaluated in a validation cohort that included 209 patients with SVT. RESULTS In the test cohort, 59 patients had JAK2V617F, five had CALR and none had MPL mutations. Patients with CALR mutations had higher spleen height and platelet count than patients without these mutations. All patients with CALR mutations had a spleen height ⩾16cm and platelet count >200×109/L. These criteria had a positive predictive value of 56% (5/9) and a negative predictive value of 100% (0/233) for the identification of CALR mutations. In the validation cohort, these criteria had a positive predictive value of 33% (2/6) and a negative predictive value of 99% (1/96). CONCLUSION CALR mutations should be tested in patients with SVT, a spleen height ⩾16cm, platelet count >200×109/L, and no JAK2V617F. This strategy avoids 96% of unnecessary CALR mutations testing. Lay summary: Mutations of the CALR gene are detected in 0 to 2% of patients with SVT, thus the utility of systematic CALR mutation testing to diagnose MPN is questionable. This study demonstrates that CALR mutations testing can be restricted to patients with SVT, a spleen height ⩾16cm, a platelet count >200×109/L, and no JAK2V617F. This strategy avoids 96% of unnecessary CALR mutations testing.

Dynamics of cytomegalovirus populations harbouring mutations in genes UL54 and UL97 in a haematopoietic stem cell transplant recipient

We characterised by pyrosequencing, the dynamics of cytomegalovirus populations harbouring mutations A594V in gene UL97 and A834P and Q578H in gene UL54 in a haematopoietic stem cell transplant recipient. Unexpected re-emergence of A594V and decrease of A834P under CMX001 were shown to depend on both the selection pressure exerted by the antiviral treatments and the immune response.

TET2 gene sequencing may be helpful for myeloproliferative neoplasm diagnosis

Jamieson et al (2004) showed that granulocyte-macrophage progenitor cells of CML-BC have acquired enhanced b-catenin activity and self-renewal capacities, it cannot fully elucidate the cell origin of CML-BC clones. Second, the expression levels of BCR-ABL1 were relatively low in the leukaemia stem cell population. Several studies, which have also examined stem cells at each differentiation stage, showed controversial results, and only reported the population averages (Jamieson et al, 2004; Jiang et al, 2007; Kumari et al, 2012). According to our data, the resistance of CML stem cells to tyrosine kinase inhibitors (TKI) might be due to the low expression of BCR-ABL1 as a result of its independent signalling pathway, which is also consistent with the report by Kumari et al (2012) that CML clones with low BCR-ABL1 expression persisted after treatment with TKI. Further analysis for multiple samples is required for validating these results. In conclusion, single-cell gene expression analysis for the leukaemiaclone-specific fusion transcripts is highly useful for investigating clonal architecture. It also has the advantage of analysing the properties of rare cell populations, such as leukaemia stem cells, which are difficult to obtain in sufficient numbers, and could be applied to the analysis of other malignancies. Conflicts of interest