Abstract
Sarcopenia, defined as the loss of muscle mass accompanied by reduced strength and/or physical performance, is associated with numerous health risks, including falls, complications, prolonged hospitalization, and increased mortality. In cancer patients, sarcopenia is not only age-related but also aggravated by tumor-induced catabolism and treatment-related effects. Studies have shown that low muscle mass negatively impacts survival across various cancer types. Early detection of sarcopenia is therefore crucial to guide nutritional interventions and optimize treatment outcomes. To evaluate the clinical utility of ultrasound in the assessment of sarcopenia among cancer patients in Vietnam. This cross-sectional study was conducted on 224 cancer patients at Ho Chi Minh City Oncology Hospital from January to April 2024. All patients underwent computed tomography scans at the level of the 3rd lumbar vertebra, and muscle ultrasound assessments were performed on 2 lower limb muscles: the tibialis anterior and gastrocnemius muscles. Sarcopenia was diagnosed based on the 2019 criteria of the Asian Working Group for Sarcopenia. The prevalence of sarcopenia in the study population was 49.1%. Ultrasound measurements showed moderate diagnostic accuracy: the area under the receiver operating characteristic curve was 0.71 for the tibialis anterior muscle and 0.70 for the gastrocnemius muscle. For the tibialis anterior muscle, the optimal cutoff point was < 2.4 cm in men (sensitivity: 64.3%, specificity: 85.7%) and < 2.2 cm in women (sensitivity: 58.5%, specificity: 81.3%). For the gastrocnemius, the cutoff was < 1.8 cm in both sexes (sensitivity: 57.5%, specificity: 71.9%). This study highlights the potential utility of muscle ultrasound (particularly of the tibialis anterior and gastrocnemius muscles) as a noninvasive, accessible tool for sarcopenia screening in cancer patients. Given the limitations of conventional methods in this population, integrating ultrasound into clinical protocols may enhance individualized care, support early interventions, and improve patient outcomes and quality of life.