Devoted to diagnostic and interventional spine imaging and therapeutics


Differentiating Hypervascular Renal and Hypovascular Prostate Spinal Metastases using Magnetic Resonance Perfusion Imaging as a Biomarker 2014

Category General Spine Atin Saha, MS
Kyung Peck, PhD
Eric Lis, MD
Andrei Holodny, MD
Sasan Karimi, MD
Purpose Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) provides an advantage over conventional MRI in that DCE-MRI provides anatomical, physiological, and hemodynamic information about neoplastic lesions. Our aim in this study was to evaluate spinal metastases from hypervascular renal cell carcinoma (RCC) and hypovascular prostate carcinoma (PC) using a T1 DCE-MRI perfusion technique and to assess the sensitivity and specificity of the perfusion parameters obtained. Materials & Methods A total of 40 patients with spinal metastases and either PC or RCC as the primary tumor were studied. DCE perfusion parameters-vascular permeability (Ktrans), plasma volume (Vp), wash-in, and peak-enhancement were measured to assess their potential as discriminators of tumor histology. A Mann-Whitney U test, at a significance level of p≤0.01, was performed to quantify and compare the significances of the perfusion parameters of PC and those of RCC. Results Of the four perfusion parameters studied, Vp was observed to have the largest difference in mean (µ) between PC (µ=3.29/sec) and RCC metastases (µ=5.92/sec). This was followed by the peak-enhancement, Ktrans, and wash-in parameters. A Mann-Whitney U test showed a significant difference between the observed Vp values for PC and RCC lesions to the spine (p≤0.001). Similarly, peak-enhancement showed a significant difference between the two histologies (p≤0.001), as did Ktrans (p≤0.01). The receiver operating characteristic (ROC) curve showed that Vp recorded the highest area under the curve (0.867). Conclusion Vp was shown to be the best discriminator between spinal metastases from PC and RCC with the mean Vp of RCC metastasis being 1.8 times that of the PC lesions, thus discriminating between hyper- and hypovascular metastases, which has important clinical implications in patient care and management. References 1. Gerszten PC, Germanwala A, Burton SA, Welch WC, Ozhasoglu C, Vogel WJ: Combination kyphoplasty and spinal radiosurgery: A new treatment paradigm for pathological fractures. Journal of Neurosurgery: Spine 3:296-301, 2005 2. Zhou XJ, Leeds NE, McKinnon GC, et al: Characterization of benign and metastatic vertebral compression fractures with quantitative diffusion MR imaging. Am J Neuroradiol 23:165-170, 2002 3. Moulopoulos L, Maris T, Papanikolaou N, et al: Detection of malignant bone marrow involvement with dynamic contrast-enhanced magnetic resonance imaging. Annals of oncology 14:152-158, 2003