Association between CT-Based Preoperative Sarcopenia and Outcomes in Patients That Underwent Liver Resections

Simple Summary

Cancer cachexia often includes sarcopenia, which is characterized by a progressive, generalized loss of skeletal muscle mass and strength, combined with fatty infiltration into the muscle. Sarcopenia has been considered a patient-specific imaging biomarker for predicting outcomes after cancer surgery. The present study aimed to evaluate whether preoperative sarcopenia was associated with postoperative outcomes and survival in patients that underwent liver resections. Sarcopenia, assessed by preoperative CT imaging, was present in two-thirds of patients. Independent risk factors for sarcopenia were age, male sex, ASA score ≥ 3, and malignancies. Based on CT assessment alone, sarcopenia had no impact on clinical outcomes or overall survival after hepatectomy.

Abstract

This retrospective observational study aimed to evaluate whether preoperative sarcopenia, assessed by CT imaging, was associated with postoperative clinical outcomes and overall survival in patients that underwent liver resections. Patients operated on between January 2014 and February 2020 were included. The skeletal muscle index (SMI) was measured at the level of the third lumbar vertebra on preoperative CT scans. Preoperative sarcopenia was defined based on pre-established SMI cut-off values. The outcomes were postoperative morbidity, length of hospital stay (LOS), and overall survival. Among 355 patients, 212 (59.7%) had preoperative sarcopenia. Patients with sarcopenia were significantly older (63.5 years) and had significantly lower BMIs (23.9 kg/m²) than patients without sarcopenia (59.3 years, p < 0.01, and 27.7 kg/m², p < 0.01, respectively). There was no difference in LOS (8 vs. 8 days, p = 0.75), and the major complication rates were comparable between the two groups (11.2% vs. 11.3%, p = 1.00). The median overall survival times were comparable between patients with sarcopenia and those without sarcopenia (15 vs. 16 months, p = 0.87). Based on CT assessment alone, preoperative sarcopenia appeared to have no impact on postoperative clinical outcomes or overall survival in patients that underwent liver resections. Future efforts should also consider muscle strength and physical performance, in addition to imaging, for preoperative risk stratification.

Bone Marrow Metastases: T2-weighted Dixon Spin-Echo Fat Images Can Replace T1-weighted Spin-Echo Images

Purpose To test the potential of Dixon T2-weighted fat-only sequences to replace T1-weighted sequences for the detection of bone metastases, with the hypothesis that diagnostic performance with an alternative magnetic resonance (MR) imaging protocol (sagittal spin-echo Dixon T2-weighted fat-only and water-only imaging) would not be inferior to that with the standard protocol (sagittal spin-echo T1-weighted and spin-echo Dixon T2-weighted water-only imaging). Materials and Methods A total of 121 consecutive whole-spine MR imaging examinations (63 men; mean age ± standard deviation, 61.4 years ± 11.8) performed for suspected vertebral bone metastases were included in this retrospective, institutional review board-approved study. Quantitative image analysis was performed for 30 randomly selected spine levels. Qualitative analysis was performed separately by two musculoskeletal radiologists, who registered the number of metastases for each spine level. Areas under the curve with the protocols were compared on the basis of nonparametric receiver operating characteristic curve estimations by using a noninferiority test on paired data, with a best valuable comparator as a reference. Interobserver and interprotocol agreement was assessed by using κ statistics. Results Contrast-to-noise ratio was significantly higher on the alternative protocol images than on the standard protocol images (181.1 [95% confidence interval: 140.4, 221.7] vs 84.7 [95% confidence interval: 66.3, 103.1] respectively; P < .001). Diagnostic performance was not significantly inferior with the alternative protocol than with the standard protocol for both readers in a per-patient analysis (sensitivity, 97.9%-98.9% vs 93.6%-97.9%; specificity, 85.2%-92.6% vs 92.6%-96.3%; area under the curve, 0.92-0.96 vs 0.95, respectively; all P ≤ .02) and a per-spine level analysis (all P < .01). Interobserver and interprotocol agreement was good to very good (κ = 0.70-0.81). Conclusion Dixon T2-weighted fat-only and water-only imaging provide, in one sequence, diagnostic performance similar to that of the standard combination of morphologic sequences for the detection of probable spinal bone metastases, thereby providing an opportunity to reduce imaging time by eliminating the need to perform T1 sequences. ^© RSNA, 2017 An earlier incorrect version of this article appeared online. This article was corrected on November 6, 2017.