¹H magnetic resonance spectroscopy of preinvasive and invasive cervical cancer: In vivo–ex vivo profiles and effect of tumor load

Abstract

Purpose: To compare in vivo 1 H magnetic resonance (MR) spectra of preinvasive and invasive cervical lesions with ex vivo magic angle spinning (MAS) spectra of intact biopsies from the same subjects and to establish the effects of tumor load in the tissue sampled on the findings. Materials and Methods:A total of 51 subjects (nine with normal cervix, 10 with cervical intraepithelial neoplasia [CIN], and 32 with cervical cancer) underwent endovaginal MR at 1.5 T. 3 )1 H MR spectra were acquired and voxel tumor load was calculated (tumor volume within voxel as a percentage of voxel volume). Resonances from triglycerides -CH 2 and -CH 3 and choline-containing compounds (Cho) were correlated with voxel tumor load. Biopsies analyzed by 1 H MAS-MR spectroscopy (MRS) had metabolite levels correlated with tumor load in the sample at histology. Results:In vivo studies detected Cho in normal, CIN, and cancer patients with no significant differences in levels (P ϭ 0.93); levels were independent of voxel tumor load. Triglyceride -CH 2 and -CH 3 signals in-phase with Cho were present in 77% and 29%, respectively, of cancer subjects (but not in normal women or those with CIN), but did not correlate with voxel tumor load. Ex vivo cancer biopsies showed levels of triglycerides -CH 2 and -CH 3 and of Cho that were significantly greater than in normal or CIN biopsies (P Ͻ 0.05); levels were independent of the tumor load in the sample. The presence of -CH 2 in vivo predicted the presence of cancer with a sensitivity and specificity of 77.4% and 93.8% respectively, positive (PPV) and negative (NPV) predictive values were 96% and 68.2%; for -CH 2 ex vivo, sensitivity was 100%; specificity, 69%; PPV, 82%; and NPV, 100%. Conclusion:Elevated lipid levels are detected by MRS in vivo and ex vivo in cervical cancer and are independent of tumor load in the volume of tissue sampled.

In vivo magnetic resonance spectroscopy of gynaecological tumours at 3.0 Tesla

“…However, the reduction in tumour volume postchemotherapy was significant, as was the reduction in triglyceride, but did not appear to represent any survival advantage. Mahon et al 7 published work involving a total of 51 patients made up of women with cervical intraepithelial neoplasia (n = 10), cervical cancer (n = 32) and normal cervical tissue (n = 9). These women underwent MR imaging and 1 H MRS using an endovaginal coil at 1.5 T, followed by magic angle spinning (MAS) MR spectroscopy of biopsies of the same tissue.…”

Phenotyping murine models of non-alcoholic fatty liver disease through metabolic profiling of intact liver tissue

“…In particular, this enabled the resolution and quantitation of the resonances within the total choline region. 32K data points were acquired for each spectrum with a spectral width of 15kHz [20]. The overall time for data acquisition was 35 minutes.…”

Quantification of metabolites in breast cancer patients with different clinical prognosis using HR MAS MR spectroscopy

“…Various methods have been used to quantify metabolites. A reference has been added to the sample or buffer (8), metabolites have been quantified using tissue water as an internal standard (1), and a silicon rubber has been added as an external standard (9,10). In addition, a relative measure of concentrations has been calculated using the spectral noise as an internal reference (11).…”