Non-contrast liver MRI as an alternative to gadoxetic acid-enhanced MRI for liver metastasis from colorectal cancer.

BACKGROUND

Liver magnetic resonance imaging (MRI) provides reliable diagnostic performance for detecting liver metastasis but is costly and time-consuming.

PURPOSE

To compare the diagnostic performance of non-contrast liver MRI to whole MRI using gadoxetic acid for detecting liver metastasis in patients with colorectal cancer (CRC).

MATERIAL AND METHODS

We included 175 patients with histologically confirmed 401 liver metastases and 73 benign liver lesions. A non-contrast MRI (T1-weighted, T2-weighted, and diffusion-weighted images) with or without multidetector computed tomography (MDCT) and a whole MRI (gadoxetic acid-enhanced and non-contrast MRI) were analyzed independently by two observers to detect liver metastasis using receiver operating characteristic analysis.

RESULTS

We found no significant differences in Az value (range = 0.914-0.997), sensitivity (range = 95.2-99.6%), specificity (range = 77.3-100%), or positive (range = 92.9-100%) or negative predictive value (range = 87.5-95.7%) between the non-contrast MRI with or without MDCT and the whole MRI for both observers for all lesions as well as lesions ≤1.0 cm and lesions >1.0 cm in size ( P = 0.203-1.000). Combined MDCT and non-contrast MRI led to similar numbers of false-positive diagnosis to the whole MRI (eight for Observers 1 and 4 vs. 3 for Observer 2).

CONCLUSION

Non-contrast liver MRI may serve as an alternative to gadoxetic acid-enhanced MRI for detecting and characterizing liver metastasis from CRC, at least in patients with relatively high risk of liver metastasis who underwent MDCT. Non-contrast liver MRI could be beneficial especially for patients with lesions that are already documented as benign but require additional follow-up MRIs.