# Imaging-based prognostic factors in patients undergoing thermal ablation for colorectal liver metastases. A retrospective study on the role of sarcopenia parameters and tumor burden score

## TL;DR

This study finds that muscle volume in the psoas muscle, measured from CT scans, is linked to better survival in patients with colorectal liver metastases treated with thermal ablation.

## Contribution

The study introduces psoas muscle volume index (PMVI) as a novel imaging-based prognostic factor for 1-year survival in CRLM patients undergoing thermal ablation.

## Key findings

- PMVI was significantly associated with 1-year survival (p = 0.048).
- L1-bone-density and PMI showed no significant survival association.
- Tumor burden score was not significantly linked to survival.

## Abstract

To investigate imaging-based prognostic factors in patients who underwent thermal ablation for colorectal liver metastases (CRLM), with a focus on sarcopenia-related body composition parameters and L1-bone-density in comparison to tumor burden score (TBS).

A retrospective analysis was conducted on patients who received thermal ablation for CRLM at our tertiary care center between 2009 and 2023. CT-derived body composition metrics included the psoas muscle volume index (PMVI), the psoas muscle index (PMI), and L1-bone-density. PMVI was automatically extracted using the open-source deep learning tool TotalSegmentator. Comparisons between 1-year survivors and non-survivors were performed using unpaired t-tests.

A total of 88 patients were included, most had previously undergone hepatic resection (n = 72, 82%). Among sarcopenia-related imaging markers, PMVI showed a significant association with 1-year survival (p = 0.048), with higher PMVI values observed in survivors (mean 113.3 cm3/m3) compared to non-survivors (mean 101.3 cm3/m3). No significant differences were observed for L1-density (p = 0.925) or PMI (p = 0.137). Similarly, the TBS was not significantly associated with 1-year survival (p = 0.182).

In our cohort of patients treated with thermal ablation for CRLM, PMVI showed significant association with 1-year survival, which was not observed for conventional tumor burden score or other sarcopenia-related imaging parameters.