Impact of early remission by induction therapy on allogeneic stem cell transplantation for acute myeloid leukemia with an intermediate risk karyotype in first complete remission

For patients with acute myeloid leukemia (AML) early achievement of remission during induction treatment is an important predictor for long-term outcome irrespective of the type of consolidation therapy employed. Here, we retrospectively examined the prognostic impact of early remission (ER) versus delayed remission (DR) in a cohort of 132 AML patients with an intermediate risk karyotype undergoing allogeneic stem cell transplantation (alloSCT) in first complete remission (CR1). In contrast to patients showing DR, patients achieving ER had a significantly higher 3-year overall survival (OS) and disease-free survival (DFS) of 76% versus 54% (p=0.03) and 76% versus 53% (p=0.03). Likewise, three years after alloSCT the cumulative incidence of relapse (CI-R) was significantly lower in the ER subgroup as compared to patients achieving DR, i.e. 10% versus 35% (p=0.004), whereas non-relapse mortality (NRM) did not differ significantly. Multivariate analysis identified DR as an independent prognosticator for an inferior DFS (HR 3.37, p=0.002) and a higher CI-R (HR 3.55, p=0.002). Taken together, these data may indicate that the rapid achievement of remission predicts a favorable outcome in patients with intermediate risk AML undergoing alloSCT in CR1. In turn, the adverse effect of DR may not be fully overcome by alloSCT

Fast unsupervised hot-spot detection in 1H-MR spectroscopic imaging data using ICA

Independent Component Analysis (ICA) is a blind source separation technique that has previously been applied to various time-varying signals. It may in particular be utilized to study 1H-MR spectroscopic imaging (MRSI) data. The work presented firstly investigates preprocessing and parameterization for ICA on simulated data to assess different strategies. We then applied ICA processing to 2D/3D brain and prostate MRSI data obtained from two healthy volunteers and 17 patients. We conducted a correlation analysis of the mixing and separating matrices resulting from ICA processing with maps obtained from metabolite quantitations in order to elucidate the relationship between quantitative and ICA results. We found that the mixing matrices corresponding to the estimated independent components highly correlate with the metabolite maps for some cases, and for others differ. We provide explanations and speculations for that and propose a scheme to utilize the knowledge for hot-spot detection. From our experience, ICA is much faster than the calculation of metabolic maps. Additionally, water and lipid contaminations are on the way removed from the data; the user needs not manually exclude spectroscopic voxels from processing or analysis. ICA results show hot spots in the data, even where quantitation-based metabolic maps are difficult to assess due to noisy data or macromolecule distortions

Megalencephalic leukoencephalopathy with subcortical cysts in an adult: quantitative proton MR spectroscopy and diffusion tensor MRI

A 37-year-old macrocephalic woman was investigated for increasing gait disturbance due to longstanding spasticity and ataxia. MRI showed widespread bilateral increase in signal from cerebral white matter on T2-weighted images. Numerous subcortical cysts were visible in anterior-temporal and parietal regions. These clinical and neuro radiological features are those of megalencephalic leukoencephalopathy with subcortical cysts (MLC), a recently delineated whitematter disease with onset in childhood. Quantitative localised proton MR spectroscopy of white matter revealed marked reduction of N- acetylaspartate, creatine, and choline with normal values for myoinositol, consistent with axonal loss and astrocytic proliferation. Diffusion tensor imaging showed an increased apparent diffusion coefficient and reduced anisotropy in affected white matter pointing to reduced cell density with an. increased extracellular space. These findings are in line with histological changes alterations known to occur in MLC

Megalencephalic leukoencephalopathy with subcortical cysts in an adult: quantitative proton MR spectroscopy and diffusion tensor MRI

A 37-year-old macrocephalic woman was investigated for increasing gait disturbance due to longstanding spasticity and ataxia. MRI showed widespread bilateral increase in signal from cerebral white matter on T2-weighted images. Numerous subcortical cysts were visible in anterior-temporal and parietal regions. These clinical and neuro radiological features are those of megalencephalic leukoencephalopathy with subcortical cysts (MLC), a recently delineated whitematter disease with onset in childhood. Quantitative localised proton MR spectroscopy of white matter revealed marked reduction of N- acetylaspartate, creatine, and choline with normal values for myoinositol, consistent with axonal loss and astrocytic proliferation. Diffusion tensor imaging showed an increased apparent diffusion coefficient and reduced anisotropy in affected white matter pointing to reduced cell density with an. increased extracellular space. These findings are in line with histological changes alterations known to occur in MLC