Abstract
Systemic mastocytosis (SM) is characterized by multifocal accumulation of neoplastic mast cells (MCs), predominately affecting the bone marrow (BM). Imaging with computed tomography (CT) is ...used for assessment of bone mineral density and structure. However, the value of functional imaging with dual-energy CT (DECT) and the assessment of virtual-non-calcium attenuation values (VNCa-AV) for visualization of BM disease burden in SM has not yet been assessed. DECT of the axial skeleton was performed in 18 patients with SM (indolent SM ISM, n = 6; smoldering SM SSM/advanced SM AdvSM, n = 12) and 18 control subjects. VNCa-AV were obtained in 5 representative vertebraes per patient and correlated with laboratory, morphologic and molecular parameters. VNCa-AV strongly correlated with quantitative BM MC infiltration (r = 0.7, R
2
= 0.49,
P
= 0.001) and serum tryptase levels (r = 0.7, R
2
= 0.54,
P
< 0.001). Mean VNCa-AV were significantly higher in SSM/AdvSM as compared to ISM (− 9HU vs. − 54HU,
P
< 0.005) and controls (− 38HU,
P
< 0.005). Nine of 10 (90%) patients with a VNCa-AV > − 30HU and 7/7 (100%) patients with a VNCa-AV > − 10HU had SSM or AdVSM. BM VNCa-AV provide information about the MC burden of SM patients and correlate with SM subtypes. DECT may therefore serve as a supplementary tool for SM diagnosis, subclassification and monitoring in a one-stop-shop session.
In systemic mastocytosis (SM), qualitative and serial quantitative assessment of the
D816V mutation is of diagnostic and prognostic relevance. We investigated peripheral blood and bone marrow samples ...of 161 patients (indolent SM (ISM),
= 40; advanced SM, AdvSM,
= 121) at referral and during follow-up for the
D816V variant allele frequency (VAF) at the DNA-level and the
D816V expressed allele burden (EAB) at the RNA-level. A round robin test with four participating laboratories revealed an excellent correlation (
> 0.99,
> 0.98) between three different DNA-assays. VAF and EAB strongly correlated in ISM (
0.91, coefficient of determination,
0.84) but only to a lesser extent in AdvSM (
0.71;
= 0.5). However, as compared to an EAB/VAF ratio ≤2 (cohort A, 77/121 patients, 64%) receiver operating characteristic (ROC) analysis identified an EAB/VAF ratio of >2 (cohort B, 44/121 patients, 36%) as predictive for an advanced phenotype and a significantly inferior median survival (3.3 vs. 11.7 years;
= 0.005). In terms of overall survival, Cox-regression analysis was only significant for the EAB/VAF ratio >2 (
= 0.006) but not for VAF or EAB individually. This study demonstrates for the first time that the transcriptional activity of
D816V may play an important role in the pathophysiology of SM.
Objective
Multidrug‐resistant organisms (MDRO) are a challenge in allogeneic hematopoietic cell transplantation (HCT). However, in the literature there is no comprehensive analysis on MDRO in HCT. In ...this retrospective, single‐center analysis, we appraised prevalence and clinical impact of MDRO in 98 consecutive allogeneic HCT patients.
Method
Prior to the conditioning (baseline) and whenever clinically indicated patients underwent a full screening for MDRO (stool and urine cultures, swabs from several body regions).
Results
It turned out that 26 patients were colonized by 33 MDRO, either at baseline (n=16) or at any other time until day 100 post‐transplantation. Of these 26 patients, eight developed an infection with MDRO, four of them by 4MRGN Pseudomonas aeruginosa, and three of them died MDRO‐related. However, there was no significant difference between MDRO‐colonized and non‐colonized patients regarding overall survival (OS) and non‐relapse‐mortality (NRM). There was only a trend toward a higher NRM in patients already colonized by MDRO at baseline. This was due to the high NRM in multidrug‐resistant P. aeruginosa‐colonized patients.
Conclusion
In summary, colonization with MDRO other than P. aeruginosa had no negative impact on NRM and OS. Patients colonized by multidrug‐resistant P. aeruginosa had a dismal outcome. HCT of these patients should be considered with care. Screening for MDRO in the pretransplant work‐up is suggested.
The incidence of mental and somatic sequelae has been shown to be very high in people who survived the Holocaust. In the current study, 80 Holocaust survivors with posttraumatic stress disorder were ...examined based on evaluation of their complete record (medical reports, clinical history, medical statements, and handwritten declarations of patients under oath). These survivors were compared with subjects with posttraumatic stress disorder caused by traumata other than the Holocaust. The data were analyzed for the presence of cardiovascular, gastrointestinal, and orthopedic diseases that developed in the time between the earliest medical report (expert opinion) and the latest expert opinion. Analysis revealed an increase in myocardial infarction, chronic degenerative diseases, and cancerous changes in the second expert opinion. No differences between the groups were seen with regard to sex, age at traumatization, or age at examination. Several implications of the data are discussed, including the implication that the survivors examined in this study may comprise a highly resilient group, inasmuch as they had reached an advanced age.
background: Mutations of the BCR-ABL tyrosine kinase domain constitute a major cause of resistance to tyrosine kinase inhibitors in patients with chronic myeloid leukemia. We sought to improve the ...diagnostic armamentarium by screening and to analyze the dynamics of mutated clones in chronic myeloid leukemia patients who experienced hematologic or cytogenetic relapse.
Ninety-five patients who relapsed during imatinib therapy were screened for BCR-ABL kinase domain mutations using sensitive denaturing high-performance liquid chromatography (D-HPLC) and direct sequencing. To investigate the dynamics of mutated clones D-HPLC was applied to 453 cDNA samples tracking back from relapse towards the start of imatinib therapy.
Twenty-two different point mutations affecting 18 amino acids were detectable in 46/79 (58%) and in 7/16 patients (44%) with hematologic or cytogenetic relapse, respectively. A deletion of 81 nucleotides (del248-274) of ABL exon 4 was observed in two patients. Three patients had exclusively single nucleotide polymorphisms (K247R, T315T, E499E, n=1 each) within the BCR-ABL kinase domain. In patients harboring mutations, hematologic relapse occurred after a median of 12.9 months (range, 0.9-44.2), and BCR-ABL mutations first became detectable at a median of 5.8 months (range, 0-30.5) after starting imatinib therapy (p<0.0001). Nine patients showed evidence of BCR-ABL mutations prior to imatinib therapy (T315I, n=4; M351T, n=3; M244V and Y253H, n=1 each).
We conclude that: (i) D-HPLC is a sensitive method for screening for BCR-ABL mutations before and during therapy with tyrosine kinase inhibitors; (ii) the occurrence of BCR-ABL mutations during imatinib therapy is predictive of relapse; (iii) mutations may be detectable several months before relapse, and (iv) the sensitive detection of small numbers of mutated clones could provide clinical benefit by triggering early therapeutic interventions.
Point mutations of the BCR-ABL tyrosine kinase domain are considered the predominant cause of imatinib resistance in chronic myeloid leukemia. The expansion of mutant BCR-ABL-positive clones under ...selective pressure of tyrosine kinase inhibition is referred to as clonal selection; there are few data on the reversibility of this phenomenon.
The changes of expression of mutant BCR-ABL-positive alleles after cessation of tyrosine kinase inhibitor treatment were examined in 19 patients with chronic myeloid leukemia harboring different mutations in a longitudinal follow-up. The proportion of mutant alleles was quantified by amplification of rearranged ABL sequences followed by mutation-specific restriction digestion, electrophoresis and densitometry. The size of mutant clones was established as a measure of the absolute amount of mutant cells considering the proportion of mutant BCR-ABL transcripts and the total level of BCR-ABL obtained by quantitative reverse transcriptase polymerase chain reaction.
The median proportion of mutant transcripts was 97% before and 8% after cessation of tyrosine kinase inhibitor treatment indicating a relative decline of 88% within a median of 6 months. The relative decrease in the size of the mutant clones was 86%. Repeated selection and deselection of the mutant clone after resumption and second cessation of tyrosine kinase inhibitor treatment was observed in individual patients.
Deselection of mutant BCR-ABL-positive clones after cessation of tyrosine kinase inhibitor treatment might be a common, rapid and reproducible phenomenon, although some patients harboring the T315I mutation showed no deselection. Cessation of tyrosine kinase inhibitor treatment may lead to the regression of T315I mutant clones to a level under the limit of detection, offering the therapeutic option of resumed tyrosine kinase inhibitor treatment under close surveillance of the mutation status.
Recent evidence has demonstrated that acquired uniparental disomy (aUPD) is a novel mechanism by which pathogenetic mutations in cancer may be reduced to homozygosity. To help identify novel ...mutations in myeloproliferative neoplasms (MPNs), we performed a genome-wide single nucleotide polymorphism (SNP) screen to identify aUPD in 58 patients with atypical chronic myeloid leukemia (aCML; n = 30), JAK2 mutation–negative myelofibrosis (MF; n = 18), or JAK2 mutation–negative polycythemia vera (PV; n = 10). Stretches of homozygous, copy neutral SNP calls greater than 20Mb were seen in 10 (33%) aCML and 1 (6%) MF, but were absent in PV. In total, 7 different chromosomes were involved with 7q and 11q each affected in 10% of aCML cases. CBL mutations were identified in all 3 cases with 11q aUPD and analysis of 574 additional MPNs revealed a total of 27 CBL variants in 26 patients with aCML, myelofibrosis or chronic myelomonocytic leukemia. Most variants were missense substitutions in the RING or linker domains that abrogated CBL ubiquitin ligase activity and conferred a proliferative advantage to 32D cells overexpressing FLT3. We conclude that acquired, transforming CBL mutations are a novel and widespread pathogenetic abnormality in morphologically related, clinically aggressive MPNs.
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