Comparison between MRS and DWI in MRI of breast cancer

Introduction: Breast cancer is the most common cancer in women and is the second leading cause of cancer death (after lung cancer) in people throughout the world. Today, MRI is being used because of the limitations of x-ray mammography to detect breast cancer. Non-contrast sequences were associated to CE sequences in a breast MRI protocol for the sake of appraising morphologic features for lesion characterization. Two non-contrast MR methods that are mainly used for internal examination of breast tissue: proton MR spectroscopy (1H- MRS) and diffusion-weighted imaging (DWI). In the H-MRS, the total choline peak (tCho) is used as a biomarker for the detection of malignancies. Also, the DWI protocol determines the quantity by measuring the average diffusivity and Apparent diffusion coefficient(ADC). DWI showed that cell diffusivity is correlated with cellularity and tumor aggressiveness. Results: when looking at a clinical perspective, while MRS remained a research tool with important limitations, such as relatively long acquisition times, frequent low quality spectra, difficult standardization, and quantification of tCho tissue concentration. In contrast, the DWI has several advantages, one of its important advantages is its high sensitivity to detect breast cancer without the need for any ionizing radiation, or an isotope injection or any other contrast agent. Additionally, the acquisition time of DWI is relatively short and can be easily repeated to provide quantitative information. This technique is independent of the magnetic’s field strength. The results of two meta-analyzes revealed a overall sensitivity in the DWI of the breast 84 and 86%, and the overall specificity was 79% and 76% respectively ,These values in the MRS are between 71 to 74% and 78 to 88%, respectively40% to 60%. Conclusion: Finally, according to studies on MRS and DWI in breast MRI, are clearly in favor of an easier and more effective use of DWI.