Diffusion-weighted Imaging of Breast Cancer with the Sensitivity Encoding Technique: Analysis of the Apparent Diffusion Coefficient Value

Abstract

Purpose: The usefulness of diffusion-weighted imaging (DWI) in the field of neuroradiology has been established. Despite its high contrast resolution, DWI has the disadvantages of susceptibility artifact and chemical shift artifact. We performed DWI of breast cancer with the sensitivity encoding (SENSE) technique. Methods: The subjects were 60 female patients with breast mass. All patients underwent MRI including SENSE-DWI and were diagnosed histologically. Of these patients, 55 were diagnosed with breast cancer and the remaining five were diagnosed with benign mass. The histological diagnoses of breast cancer were as follows: 39 cases of invasive ductal carcinoma (IDC); 11 cases of IDC with a predominant intraductal component and non IDC (pure or predominant NIDC); and five cases of special types of cancer. The MR system used was a Gyroscan Intera 1.5T (Philips Medical Systems). In addition to routine MRI for breast cancer, including contrast-enhanced dynamic, SENSE-DWI was obtained. The accuracy of the positional information of SENSE-DWI was visually compared with that of conventional images. The apparent diffusion coefficient (ADC) values of breast mass were analyzed with SENSE-DWI. Results: The accuracy of positional information was adequate for diagnosing of all patients. The mean ADC value of breast cancer was 1.021×10^-3 mm²/s and that of benign mass was 1.488×10^-3 mm²/s (p=0.0002). The mean ADC value of IDC was 0.968×10^-3 mm²/s and that of pure or predominant NIDC was 1.218×10^-3 mm²/s (p=0.0011). Conclusion: SENSE-DWI was of sufficient quality to support diagnosis of breast mass. SENSE-DWI may permit the acquisition of more detailed information about lesions, including tumor cellularity, that is difficult to obtain with conventional techniques.