Imaging correlates of molecular signatures in oligodendrogliomas
ABSTRACT Molecular subsets of oligodendroglioma behave in biologically distinct ways. Their locations in the brain, rates of growth, and responses to therapy differ with their genotypes. Retrospectively, we inquired whether allelic loss of chromosomal arms 1p and 19q, an early molecular event and favorable prognostic marker in oligodendrogliomas, were reflected in their appearance on magnetic resonance imaging. Loss of 1p and 19q was associated with an indistinct border on T(1) images and mixed intensity signal on T(1) and T(2). Loss of 1p and 19q was also associated with paramagnetic susceptibility effect and with calcification, a common histopathological finding in oligodendrogliomas. These data encourage prospective evaluation of molecular alterations and magnetic resonance imaging characteristics of glial neoplasms.
SourceAvailable from: Amy Miner RossJournal of Cancer Therapy 11/2014; 5. DOI:10.4236/jct.2014.513126
Journal of Neuro-Oncology 04/2015; DOI:10.1007/s11060-015-1790-5 · 2.79 Impact Factor
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ABSTRACT: A higher extent of resection (EOR) in WHO grade II gliomas (GIIG) is correlated with longer survival. However, the molecular markers also feature prognostic relevance. Here, we examined whether maximal EOR was related to the genetic profile. We retrospectively investigated the predictive value of 1p19q, IDH1, 53 expression and Ki67 index for the EOR in 200 consecutive GIIGs (2007-2013). Data were modeled in a linear model. The analysis was performed with two statistical methods (arcsin-sqrt and Beta-regression model with logit link). There was no deletion 1p19q in 118 cases, codeletion 1p19q (57 cases), single deletion 1p (4 cases) or19q (16 cases). 155 patients had a mutation of IDH1. p53 was graded in 4 degrees (0:92 cases, 1:52 cases, 2:31 cases, 3:8 cases). Mean Ki67 index was 5.2 % (range 1-20 %). Mean preoperative tumor volume was 60.8 cm(3) (range 3.3-250 cm(3)) and mean EOR was 0.917 (range 0.574-1). The statistical analysis was significant for a lower EOR in patients with codeletion 1p19q (OR 0.738, p = 0.0463) and with a single deletion 19q (OR 0.641, p = 0.0168). There was no significant correlation between IDH1 or p53 and the EOR. Higher Ki67 was marginally associated with higher EOR (p = 0.0603). The study demonstrates in a large cohort of GIIG that a higher EOR is not attributable to favorable genetic markers. This original result supports maximal surgical resection as an important therapeutic factor per se to optimize prognosis, independently of the molecular pattern.Journal of Neuro-Oncology 09/2014; 121(1). DOI:10.1007/s11060-014-1623-y · 2.79 Impact Factor