# Is Nutritional Ultrasound as Useful and Accurate as Computed Tomography to Assess Sarcopenia in Cancer Patients? A Systematic Review

## TL;DR

This review compares nutritional ultrasound to CT scans for assessing muscle loss in cancer patients and finds that ultrasound is a viable alternative.

## Contribution

The study evaluates the accuracy of nutritional ultrasound compared to CT for diagnosing sarcopenia in cancer patients.

## Key findings

- Nutritional ultrasound is accurate and useful for assessing low muscle mass in cancer patients.
- Six studies involving 1011 patients showed comparable results between nutritional ultrasound and CT.
- Ultrasound offers a more flexible and closer follow-up option than CT for sarcopenia diagnosis.

## Abstract

Sarcopenia is an important issue in patients with cancer, as it worsens response to cancer treatment and prognosis. Low muscle mass is a criterion for sarcopenia that must be evaluated in patients at risk of malnutrition, including those with cancer. To date, muscle mass is mainly assessed by computed tomography (CT) in an opportunistic way, as it is performed to evaluate cancer stage and response to treatment. Nutritional ultrasound (NU) is an emergent technique to assess muscle mass, and the objective of this systematic review is to evaluate its usefulness and accuracy for this purpose, comparing it with CT. A total of 1011 patients with cancer were included in the six articles found in this review, which shows that NU is useful and accurate enough to be used in the clinical setting to evaluate low muscle mass in the follow-up of patients with cancer.

Background: Sarcopenia assessment provides significant prognostic information that outperforms body mass index and will help to guide interventions to optimize survival outcomes in cancer patients. Computed tomography (CT) is an opportunistic tool used for the assessment of low muscle mass criteria of sarcopenia in cancer patients, while nutritional ultrasound (NU) cutoff points for sarcopenia have been recently proposed. The objective of the present review is to evaluate if NU has a comparable accuracy as CT for the assessment of sarcopenia in cancer patients and could be useful in clinical setting. Methods: Systematic review was registered in Open Science Framework. PubMed and Scopus databases were searched in May and updated in August 2025. All published studies in which patients were evaluated using only one of the previously mentioned modalities, or those involving subjects with non–cancer-related pathologies, were excluded. Two reviewers independently evaluated the risk of bias of selected studies with the National Institutes of Health (NIH) Quality Assessment Tools, and results are presented following the PRISMA 2020 model for systematic reviews. Results: Six studies comprising a total of 1011 patients (57.27% male) were evaluated. Accuracy, variability, and agreement between NU and CT are presented. Conclusions: Main limitations of the evidence include the heterogeneity among studies and their risk of bias. Nevertheless, NU can be a useful tool for sarcopenia diagnosis and can provide a closer and a more flexible follow-up in cancer patients than CT.