Preoperative MRI radiomic analysis for predicting local tumor progression in colorectal liver metastases before microwave ablation

Abstract

Purpose

Radiomics may aid in predicting prognosis in patients with colorectal liver metastases (CLM). Consistent data is available on CT, yet limited data is available on MRI. This study assesses the capability of MRI-derived radiomic features (RFs) to predict local tumor progression-free survival (LTPFS) in patients with CLMs treated with microwave ablation (MWA).

Methods

All CLM patients with pre-operative Gadoxetic acid-MRI treated with MWA in a single institution between September 2015 and February 2022 were evaluated. Pre-procedural information was retrieved retrospectively. Two observers manually segmented CLMs on T2 and T1-Hepatobiliary phase (T1-HBP) scans. After inter-observer variability testing, 148/182 RFs showed robustness on T1-HBP, and 141/182 on T2 (ICC > 0.7).

Cox multivariate analysis was run to establish clinical (CLIN-mod), radiomic (RAD-T1, RAD-T2), and combined (COMB-T1, COMB-T2) models for LTPFS prediction.

Results

Seventy-six CLMs (43 patients) were assessed. Median follow-up was 14 months. LTP occurred in 19 lesions (25%).

CLIN-mod was composed of minimal ablation margins (MAMs), intra-segment progression and primary tumor grade and exhibited moderately high discriminatory power in predicting LTPFS (AUC = 0.89, p = 0.0001). Both RAD-T1 and RAD-T2 were able to predict LTPFS: (RAD-T1: AUC = 0.83, p = 0.0003; RAD-T2: AUC = 0.79, p = 0.001). Combined models yielded the strongest performance (COMB-T1: AUC = 0.98, p = 0.0001; COMB-T2: AUC = 0.95, p = 0.0003). Both combined models included MAMs and tumor regression grade; COMB-T1 also featured 10^th percentile of signal intensity, while tumor flatness was present in COMB-T2.

Conclusion

MRI-based radiomic evaluation of CLMs is feasible and potentially useful for LTP prediction. Combined models outperformed clinical or radiomic models alone for LTPFS prediction.

Keywords:

• Liver
• metastasis
• magnetic resonance imaging
• ablation
• precision medicine

Acknowledgments

Stephanie Steidler contributed to language editing.

Ethical approval

This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of IRCCS Ospedale San Raffaele (Date: 12/09/2019; No: 137/INT/2019).

Consent to participate

Informed consent was obtained from all individual participants included in the study.

Author’s contributions

All authors contributed to study conceptualization. Methodology, data curation and formal analysis were performed by Angelo Della Corte, Martina Mori, Francesca Calabrese, Domenico Santangelo and Alessandro Pellegrini. The first draft of the manuscript was written by Angelo Della Corte and Martina Mori and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding author, A.D.C, upon reasonable request.

Additional information

Funding

The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.