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A letter to the editor is presented regarding the relevance of whole-genome amplified DNA in the analysis of the mutation frequency of the acute myeloid leukemia (AML).

Treatment of chronic myeloid leukemia (CML) with tyrosine kinase inhibitors has advanced to a stage where many patients achieve very low or undetectable levels of disease. Remarkably, some of these patients remain in sustained remission when treatment is withdrawn, suggesting that they may be at least operationally cured of their disease. Accurate definition of deep molecular responses (MRs) is therefore increasingly important for optimal patient management and comparison of independent data sets. We previously published proposals for broad standardized definitions of MR at different levels of sensitivity. Here we present detailed laboratory recommendations, developed as part of the European Treatment and Outcome Study for CML (EUTOS), to enable testing laboratories to score MR in a reproducible manner for CML patients expressing the most common BCR-ABL1 variants. [ABSTRACT FROM AUTHOR]

Chronic myeloid leukemia (CML) stem cells appear resistant to tyrosine kinase inhibitors (TKIs) in vitro, but their impact and drug sensitivity in vivo has not been systematically assessed. We prospectively analyzed the proportion of Philadelphia chromosome-positive leukemic stem cells (LSCs, Ph+CD34+CD38−) and progenitor cells (LPCs, Ph+CD34+CD38+) from 46 newly diagnosed CML patients both at the diagnosis and during imatinib or dasatinib therapy (ClinicalTrials.gov NCT00852566). At diagnosis, the proportion of LSCs varied markedly (1-100%) between individual patients with a significantly lower median value as compared with LPCs (79% vs 96%, respectively, P=0.0001). The LSC burden correlated with leukocyte count, spleen size, hemoglobin and blast percentage. A low initial LSC percentage was associated with less therapy-related hematological toxicity and superior cytogenetic and molecular responses. After initiation of TKI therapy, the LPCs and LSCs rapidly decreased in both therapy groups, but at 3 months time point the median LPC level was significantly lower in dasatinib group compared with imatinib patients (0.05% vs 0.68%, P=0.032). These data detail for the first time the prognostic significance of the LSC burden at diagnosis and show that in contrast to in vitro data, TKI therapy rapidly eradicates the majority of LSCs in patients. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which discusses the prognostic effect of 17p deletion and mutation of TP53 gene to mantle cell lymphoma (MCL).

The dic(9;20)(p13.2;q11.2) is reported to be present in ∼2% of childhood B-cell precursor acute lymphoblastic leukemia (BCP ALL). However, it easily escapes detection by G-banding analysis and its true prevalence is hence unknown. We performed interphase fluorescence in situ hybridization analyses-in a three-step manner-using probes for: (i) CDKN2A at 9p21, (ii) 20p and 20q subtelomeres and (iii) cen9 and cen20. Out of 1033 BCP ALLs diagnosed from 2001 to 2006, 533 were analyzed; 16% (84/533) displayed 9p21 deletions, of which 30% (25/84) had dic(9;20). Thus, dic(9;20)-positivity was found in 4.7% (25/533), making it the third most common genetic subgroup after high hyperdiploidy and t(12;21)(p13;q22). The dic(9;20) was associated with a female predominance and an age peak at 3 years; 18/25 (72%) were allocated to non-standard risk treatment at diagnosis. Including cases detected by G-banding alone, 29 dic(9;20)-positive cases were treated according to the NOPHO ALL 2000 protocol. Relapses occurred in 24% (7/29) resulting in a 5-year event-free survival of 0.69, which was significantly worse than for t(12;21) (0.87; P=0.002) and high hyperdiploidy (0.82; P=0.04). We conclude that dic(9;20) is twice as common as previously surmised, with many cases going undetected by G-banding analysis, and that dic(9;20) should be considered a non-standard risk abnormality. [ABSTRACT FROM AUTHOR]

Background: So far there are no studies comparing the attitudes of patients with hereditary conditions to the attitudes of the general public on how to handle genetic risk information which mutation carriers refuse to disclose to relevant family members. The purpose of the present study was to investigate whether such patients and members of the general public want to be informed about the existence of hereditary conditions within their family, and under which conditions they want healthcare providers to breach confidentiality. Methods: It was hypothesized that the desire to be informed would be influenced by characteristics of both the disease and the individual. Systematically varying 3 disease characteristics (fatality, penetrance and treatment availability) yielded 8 versions of a questionnaire, which was administered to general population samples in Norway and Sweden (N = 3,207) and to patient samples in both countries (N = 822). Individual differences in uncertainty avoidance, coping style and consideration for future consequences were also assessed. Results and Conclusion: A majority of both patients and the general public want to be informed about the existence of hereditary conditions within their family. However, patients are more positive towards being informed, both with and without the relative's consent, than the general public. The main predictor of the desire to be informed was uncertainty avoidance in both samples. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding a study which examines the use of RNA sequencing (RNA-seq) to identify clinically relevant fusion genes in leukemia cells.