The effect of pretreatment CT-assessed low skeletal muscle mass and treatment-related muscle mass loss on prognosis in patients with bone and soft tissue sarcomas: an updated meta-analysis

Objective Sarcopenia has been recognized as an important biomarker of adverse clinical outcomes across a wide range of malignancies. However, existing evidence regarding the impact of low skeletal muscle mass on the prognosis of bone and soft tissue sarcomas remains inconsistent. This study aimed to perform an updated meta-analysis to comprehensively evaluate the effects of pretreatment CT-assessed low skeletal muscle mass and treatment-related skeletal muscle mass loss on clinical outcomes in patients with bone and soft tissue sarcomas. Methods A systematic literature search was conducted in PubMed, Embase, and the Cochrane Library to identify studies investigating the associations between baseline low skeletal muscle mass, treatment-related muscle mass loss, and clinical outcomes in patients with bone and soft tissue sarcomas. The outcomes were overall survival (OS), disease-related survival outcomes and postoperative complications (PC). The quality of included studies was assessed using the Quality In Prognostic Studies (QUIPS) tool. This meta-analysis was registered in PROSPERO (CRD42025640369) and conducted in accordance with the PRISMA guidelines. Results Eighteen studies involving 1,684 patients were included. The results showed that low skeletal muscle mass was significantly associated with inferior OS, with a pooled hazard ratio of 1.72 [95% confidence interval (CI) 1.38–2.13; I 2 = 31.3%; p < 0.001] in the mixed model in 17 studies. In the analysis restricted to multivariable adjusted HRs, pretreatment low skeletal muscle mass was significantly associated with OS (HR = 2.54; 95%CI = 1.86–3.48; p < 0.001) in 7 studies. Pretreatment low skeletal muscle mass was significantly associated with an increased risk of PC [odds ratio (OR) = 1.41; 95%CI = 1.15–1.74; p = 0.001]. In addition, skeletal muscle mass loss significantly was associated with worse OS (HR = 1.61; 95%CI = 1.32–1.96; p < 0.001). Exploratory subgroup analyses showed that the prognostic factor was significantly associated with OS in patients receiving surgical resection (HR = 1.71; 95%CI = 1.33–2.22; p < 0.001) and other treatment (HR = 1.67; 95%CI = 1.09–2.56; p = 0.020). According to the QUIPS assessment, only two studies were at low overall risk of bias, whereas eight were at moderate risk and eight at high risk. GRADE profiling rated the overall certainty of evidence for OS as low, limited by serious risk of bias, inconsistency, and imprecision, but partially offset by large effect sizes and a dose–response gradient. Conclusion Both pretreatment CT-assessed low skeletal muscle mass and muscle mass loss are significantly associated with adverse prognosis in adult patients with bone and soft tissue sarcomas. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/view/CRD42025640369 , CRD42025640369.