Proton magnetic resonance spectroscopy predicts concurrent chemoradiotherapy response and time-to-progression in high-grade gliomas after surgery

IntroductionReliable early prediction response to therapy and time-to progression (TTP) remains an important goal of High-grade glioma (HGG) research. Proton magnetic resonance spectroscopy (H-MRS) has been applied with variable success in clinical application, and we hypothesize that 1H-MRS in predictive value should perform well as a marker of TTP in patients treated with concomitant chemoradiotherapy (CRT) after surgeryMethods(1)H-MRS was performed before surgery on 25 patients who had undergone resection of HGGs and fulfilled the inclusion criteria from 43 patients; then the ratios of lipid/creatine (Lip/Cr) and myoinositol/creatine (mI/Cr) were determined in the solid tumor. CRT 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.ResultsMultivariate 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.ConclusionThe ratios of Lip/Cr and mI/Cr of the solid tumor region before surgery could provide important information in predicting CRT response and TTP in patients with HGGs treated by concurrent chemoradiation after surgery.