ABSTRACT
<p><b>BACKGROUND</b>Reliable early prediction response to therapy and time-to-progression (TTP) remain an important goal of high-grade gliomas (HGGs) research. Proton magnetic resonance spectroscopy ((1)H-MRS) has been applied with variable success in clinical application, and we hypothesize that (1)H-MRS in predictive value should perform well as a marker of TTP in patients treated with radiotherapy (RT) after surgery.</p><p><b>METHODS</b>(1)H-MRS was performed before surgery on 25 patients who had undergone resection of HGGs; then the ratios of lipid/creatine (Lip/Cr) and myo-inositol/creatine (mI/Cr) were determined in the solid tumor. RT response was classified as follows: complete resolution (CR), partial response (PR), stable disease (SD), and progressive disease (PD) by comparison of pre-treatment and post-radiotherapy scans. TTP was defined at the time to radiographic progression by MacDonald criteria. Correlation was evaluated between the ratios of Lip/Cr, mI/Cr and treatment response, TTP. The chi-square test and Pearson correlation test were used for data analyses.</p><p><b>RESULTS</b>Multivariate analysis revealed that the prognostic value of spectroscopic variables was independent of age, sex, WHO histologic grade, extent of surgery, and Karnofsky score (KPS). The correlation between the ratios of lipid/Cr and TTP was significant (r = 0.894, P = 0.000), and between the ratios of mI/Cr and TTP was also significant (r = 0.891, P = 0.000). As predicted, RT response correlated significantly with TTP (r = 0.59, P = 0.002): median TTP was 49.9 days for patients with PD compared with 202.7 days for SD, 208.0 days for PR, and 234.5 days for CR.</p><p><b>CONCLUSION</b>The ratios of Lip/Cr and mI/Cr of the solid tumor region before surgery could provide important information in predicting RT response and TTP in patients with HGGs treated by radiation alone after surgery.</p>
Subject(s)
Humans , Glioma , Radiotherapy , General Surgery , Magnetic Resonance Spectroscopy , Methods , Multivariate AnalysisABSTRACT
<p><b>OBJECTIVE</b>To assess the diagnostic value of magnetic resonance imaging (MRI) in the follow-up of patients with hepatocellular carcinomas treated with radiofrequency ablation (RFA) and to compare it with that of computed tomography (CT).</p><p><b>METHODS</b>From December 2009 to September 2011, 40 patients (47 hepatocellular carcinomas) were treated with RFA after transcatheter arterial chemoembolization and underwent MRI and CT for follow-up. RFA margins were assessed on a five-point scale with receiver operating characteristic curve analysis. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were evaluated.</p><p><b>RESULTS</b>The interobserver agreement rate for MRI was significantly higher (Kappa=0.935) than for CT (Kappa=0.714; P < 0.05). The scores of 1 and 5 points for MRI, which confirms the presence or absence of residual tumor, accounted for 89.4% (84/94), while for CT accounting for only 31.9% (30/94). The area under the receiver operating characteristic curve of MRI was significantly higher than that of CT (P < 0.05), as were the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of detection rate (mean, 100%, 96.4%, 76.9%, 100%, and 96.8% for MRI, respectively, vs. 30.0%, 57.1%, 10.3%, 87.7%, and 63.8% for CT).</p><p><b>CONCLUSION</b>MRI is superior to CT in assessing the RFA margins in terms of the diagnostic accuracy and detection rate .</p>