Abbreviated and Ultrafast Dynamic Contrast-enhanced (DCE) MR Imaging

Abstract

The early detection and treatment of breast cancer is extremely important for extending patients' outcomes. Breast MRI has high sensitivity for the detection of breast cancer and plays an important role in breast cancer diagnosis and treatment, but conventional dynamic contrast-enhanced (DCE) MRI may be too time-consuming for breast cancer screening purposes. Abbreviated MRI is a technique that can be applied within a short time, as usually only the pre-contrast and first post-contrast images from the dynamic study or additional T2-weighted imaging are used. Abbreviated MRI may thus be suitable for breast cancer screening. In addition, its diagnostic performance for differentiating benign and malignant breast lesions is superior to that of breast tomosynthesis and comparable to that of conventional DCE MRI. The usefulness of abbreviated MRI for patients with a history of breast cancer and in clinical settings has been described, but the specificity of abbreviated DCE MRI is slightly lower than that of conventional DCE MRI. Ultrafast DCE MRI is a technique that obtains kinetic information by capturing multiple time phases in a short time scan in the very early phase after the injection of contrast material. Various parameters, including the maximum slope and time to enhancement can be used to evaluate kinetic information. Based on this kinetic information, ultrafast DCE MRI can differentiate between benign and malignant breast lesions. Since background parenchymal enhancement (BPE) is weak in the very early phase after a contrast media injection, ultrafast DCE MRI is also useful for identifying lesions in patients with marked BPE on conventional DCE MRI. In addition, ultrafast DCE MRI is useful for predicting the prognostic marker status of breast cancer, assessing the effectiveness of neoadjuvant therapy, examining MRI-detected lesions before surgery, and morphological assessments.

Keywords: abbreviated; breast; dynamic contrast-enhanced; magnetic resonance imaging; ultrafast.

Fig. 1

The conventional DCE MRI, abbreviated MRI, and ultrafast DCE MRI protocols. DCE, dynamic contrast-enhanced; DWI, diffusion weighted image; MIP, maximum intensity projection; T1WI, T1-weighted image; T2WI, T2-weighted image.

Fig. 2

Schema of each parameter of ultrafast DCE MRI. AUC, area under the curve; BAT, bolus arrival time; DCE, dynamic contrast-enhanced; MS, maximum slope; TTE, time to enhancement; TTP, time to peak; WIS, wash in slope.

Fig. 3

A 67 year-old woman with invasive carcinoma of no special type at the left breast (a, b) and a 55 year-old woman with a benign lesion (mastopathy) at the left breast (c, d). (a, c) MIP images obtained with ultrafast DCE MRI. (b, d) Time-intensity curves of ultrafast DCE MRI. The breast cancer shows a higher MS (30.56) and shorter TTE (2.9 sec) compared to the benign lesion (MS: 8.74, TTE: 11.6 sec). DCE, dynamic contrast-enhanced; MIP, maximum intensity projection; MS, maximum slope; TTE, time to enhancement.

Fig. 4

A 50 year-old woman with invasive carcinoma of no special type at the left breast. (a) Early phase of conventional DCE MRI, (b) ultrafast DCE MRI (9/30 phase). In the early phase of conventional DCE MRI (a), the lesion overlaps with the marked BPE, making it difficult to detect the lesion. In ultrafast DCE MRI, lesion detection is easy because the BPE is weak (b). BPE, background parenchymal enhancement; DCE, dynamic contrast-enhanced.

Fig. 5

A 45 year-old woman with invasive carcinoma of no special type at the right breast (a, b) and a 57 year-old woman with DCIS at the left breast (c, d). (a, c) The early phase of conventional DCE MRI, and (b, d) ultrafast DCE MRI (20/30 phase). In the mass lesion, an irregular to spiculated margin and rim enhancement was revealed by both conventional and ultrafast DCE MRI. In the non-mass enhancement, the lesion shows clustered ring enhancement (suggesting DCIS) on conventional DCE MRI, but the lesion shows clumped enhancement (not clustered ring enhancement) on ultrafast DCE MRI. DCE, dynamic contrast-enhanced; DCIS, ductal carcinoma in situ.