Enhancement of colorectal cancer liver metastases with gadoxetate-enhanced MRI at multiple time points is associated with disease free survival following hepatectomy.

Abstract

Aim: Investigate signal intensity of colorectal liver metastases (CRLM) at hepatobiliary phase (HBP) gadoxetate-enhanced MRI at two time points pre- (TP1) and post- chemotherapy (TP2) and association with disease-free survival (DFS) in patients undergoing curative liver resection.

Methods: Retrospective study. Single largest tumours outlined and HBP T1 signal intensity measured, normalised to skeletal muscle at TP1 and TP2. Enhancement thresholds defined and risk groups at each TP and Kaplan-Meier survival curves compared using the log-rank test. Univariate and multivariate association of enhancement and 8 clinical features with risk of recurrence calculated using Cox proportional hazards.

Results: 82 patients (48 male, mean age 59 years) underwent 135 imaging studies, 58 at TP1, 77 at TP2 and 53 patients at TP1 + 2. Of 82 patients, 58 recurred with median time to recurrence 11.7 months. Enhancement of > =135 and > =15 at TP1 and TP2 respectively were predictive of reduced risk of recurrence (p < 0.05), although not when corrected for multiple testing (p = 0.33 and 0.20 respectively). Enhancement was not associated with recurrence in multivariate model including 8 clinical features (p > 0.05). Change in enhancement between TP was not associated with risk of recurrence however tumours that consistently exhibited low enhancement were 9 times more likely to recur.

Conclusions: Increased CRLM enhancement in the HBP following gadoxetic acid at two TPs is associated with improved DFS in patients undergoing liver resection. This initial observation warrants further investigation of serial enhancement measurements as prognostic biomarkers.

Advances in knowledge: Dual-timepoint signal assessment may be informative for clinical outcomes in CRLM undergoing resection.