Survival analysis in patients with glioblastoma multiforme: Predictive value of choline‐to‐n‐acetylaspartate index, apparent diffusion coefficient, and relative cerebral blood volume

Abstract
Purpose To investigate the potential value of pre‐external‐beam radiation therapy (XRT) choline‐to‐NAA (N‐acetylaspartate) index (CNI), apparent diffusion coefficient (ADC), and relative cerebral blood volume (rCBV) for predicting survival in newly diagnosed patients with glioblastoma multiforme (GBM). Materials and Methods Twenty‐eight patients with GBM were studied using in vivo proton magnetic resonance spectroscopic imaging (1H MRSI) and diffusion‐ and perfusion‐weighted imaging after surgery but prior to XRT. Patients were categorized on the basis of their volumes of morphologic and metabolic abnormalities (volume of CNI ≥ 2 and CNI values), normalized ADC (nADC), or rCBV values within the T1 contrast‐enhancing and T2 regions. The median survival time was compared. Results A significantly shorter median survival time was observed for patients with a large volume of metabolic abnormality than for those with a small abnormality (12.0 and 17.1 months, respectively, P = 0.002). A similar pattern was observed for patients with a low mean nADC value compared to those with high mean nADC value within the T2 region (11.2 and 21.7 months, respectively, P = 0.004). A shorter median survival time was also observed for patients with contrast‐enhancing residual disease than for those without the presence of contrast enhancement with marginal significance. Conclusion The pre‐XRT volume of the metabolic abnormality and the nADC value within the T2 region may be valuable in predicting outcome for patients with GBM. J. Magn. Reson. Imaging 2004;19:546–554.