Comparative utility of MRI perfusion with MSIDR and DWIBS for the characterization of breast tumors

摘要

Background: In recent years, breast magnetic resonance imaging (MRI) has been used to evaluate the morphology and functional markers of breast lesions, which might influence local staging and surgical planning. Purpose: To evaluate the feasibility of a one stop MRI protocol combined with diffusion-weighted imaging with background body signal suppression (DWIBS), T2 *- weighted perfusion imaging (T2 *-PWI) and delayed contrast-enhanced T1-weighted MRI (T1W-C+). Material and Methods: All experiments were conducted with a 3-T clinical MRI scanner. The apparent diffusion coefficient (ADC) and detectability of lesions in DWIBS, the maximal signal intensity drop rate (MSIDR) in T2 *-PWI and the intensity increasing rate (IIR) on T1W-C+ were compared between breast malignancies (n = 29) and benign lesions (n = 31). The time-signal curves in the T2 *-PWI sequences were classified into two subtypes (a and b) according to the end of the curve. The ADC, MSIDR, the first maximal signal intensity decrease time (MSIDT), and IIR between the malignant and benign lesions were statistically analyzed by unpaired t-tests. Results: Overall, 90% of the lesions were detected by DWIBS. There were significant differences in ADC, MSIDR, and IIR between the carcinomas and benign lesions. The Ib subtype in T2 *-PWI demonstrated a specificity of 66.7% in differentiating between carcinomas and benign lesions. At a fixed specificity of 93.5%, the MSIDR, IIR, and ADC differentiated breast carcinomas from benign lesions with sensitivities of 82.8%, 44.8%, and 86.2%, respectively. Conclusion: DWIBS might be a compensation sequence for detecting breast lesions in pre-contrast sequences. MSIDR from T2 *-PWI had the best specificity index, and the two subtypes in the T2 *-PWI curve were helpful in the differential diagnosis of carcinomas from benign lesions.