Evaluation of Response to Stereotactic Radiosurgery in Brain Metastases Using Multiparametric Magnetic Resonance Imaging and a Review of the Literature

Aims

Following stereotactic radiosurgery (SRS), brain metastases initially increase in size in up to a third of cases, suggesting treatment failure. Current imaging using structural magnetic resonance imaging (MRI) cannot differentiate between tumour recurrence and SRS-induced changes, creating difficulties with patient management. Combining multiparametric MRI techniques, which assess tissue physiological and metabolic information, has shown promise in answering this clinical question.

Serial measurement of hepatic lipids during chemotherapy in patients with colorectal cancer: a 1H MRS study

Hepatic steatosis is a hallmark of chemotherapy‐induced liver injury. We made serial ¹H MRS measurements of hepatic lipids in patients over the time course of a 24‐week chemotherapeutic regimen to determine whether ¹H MRS could be used to monitor the progression of chemotherapy‐induced steatosis. Thirty‐four patients with stage III or IV colorectal cancer receiving 5‐fluorouracil, folinic acid and oxaliplatin (n = 21) or hepatic arterial infusion of floxuridine with systemic irinotecan (n = 13) were studied prospectively. ¹H MRS studies were performed at baseline and after 6 and 24 weeks of treatment. A ¹H MR spectrum was acquired from the liver during a breath hold and the ratio of fat to fat + water (FFW) was calculated to give a measure of hepatic triglycerides (HTGCs). The methodology was histologically validated in 18 patients and the reproducibility was assessed in 16 normal volunteers. Twenty‐seven patients completed baseline, 6‐week and 24‐week ¹H MRS examinations and one was censored. Thirteen of 26 patients (50%) showed an increase in FFW after completion of treatment. Six patients (23%) developed hepatic steatosis and two patients converted from steatosis to nonsteatotic liver. Patients whose 6‐week hepatic lipid levels had increased significantly relative to baseline also had a high probability of lipid elevation relative to baseline at the completion of treatment. Serial ¹H MRS is effective for the monitoring of HTGC changes during chemotherapy and for the detection of chemotherapy‐associated steatosis. Six of 26 patients developed steatosis during chemotherapy. Lipid changes were observable at 6 weeks. Copyright © 2012 John Wiley & Sons, Ltd.     

Impact of next generation sequencing on diagnostics in a genetic skin disease clinic

Individuals with inherited skin diseases often pose one of the most difficult diagnostic challenges in dermatology. The hunt for the underlying molecular pathology may involve candidate gene screening or linkage analysis, which is usually determined by the initial history, the physical findings and laboratory tests. Recent technical advances in DNA sequencing, however, are shifting the diagnostic paradigm. Notably, next‐generation sequencing allows a more comprehensive approach to diagnosing inherited diseases, with potential savings of both time and money. In the setting of a paediatric dermatology genetics clinic in Kuwait, we therefore performed whole‐exome sequencing on seven individuals without a priori detailed knowledge of the patients’ disorders: from these sequencing data, we diagnosed X‐linked hypohidrotic ectodermal dysplasia (two cases), acrodermatitis enteropathica, recessive erythropoietic protoporphyria (two siblings) and localized recessive dystrophic epidermolysis bullosa (two siblings). All these groups of disorders are clinically and genetically heterogeneous, but the sequencing data proved inherently useful in improving patient care and avoiding unnecessary investigations. Our observations highlight the value of whole‐exome sequencing, in combination with robust bioinformatics analysis, in determining the precise molecular pathology and clinical diagnosis in patients with genetic skin disorders, notably at an early stage in the clinical evaluation of these often complex disorders and thereby support a new paradigm for future diagnostics.     

Epigenetics in the hematologic malignancies

A wealth of genomic and epigenomic data has identified abnormal regulation of epigenetic processes as a prominent theme in hematologic malignancies. Recurrent somatic alterations in myeloid malignancies of key proteins involved in DNA methylation, post-translational histone modification and chromatin remodeling have highlighted the importance of epigenetic regulation of gene expression in the initiation and maintenance of various malignancies. The rational use of targeted epigenetic therapies requires a thorough understanding of the underlying mechanisms of malignant transformation driven by aberrant epigenetic regulators. In this review we provide an overview of the major protagonists in epigenetic regulation, their aberrant role in myeloid malignancies, prognostic significance and potential for therapeutic targeting.