Skeletal Muscle Index–Based Cachexia Index as a Predictor of Prognosis in Patients With Cancer: A Meta-Analysis and Systematic Review

Abstract Context Cachexia is associated with poor survival rates. In the clinical setting, the diagnosis of cancer cachexia is challenging. The cachexia index (CXI), a new index for predicting survival time, is a promising tool for diagnosing cancer cachexia; however, its efficacy in predicting patient survival has not been validated. Objective This meta-analysis and systematic review aimed to explore the CXI’s prognostic value in patients with cancer. Data Sources The PubMed, Embase, MEDLINE, and Cochrane Library databases were searched for relevant studies to determine the association between CXI findings and prognosis. Data Extraction The outcomes were overall survival (OS), progression-, disease-, and recurrence-free survival (PFS/DFS/RFS) rates, and the rate of complete response. Data Analysis The QUality In Prognostic Studies (QUIPS) tool was used to evaluate the quality of the included trials. This meta-analysis comprised 14 studies involving 2777 patients. A low CXI was associated with decreased OS (hazard ratio [HR] 2.34, 95% confidence interval [CI] 2.01–2.72; P < .001), PFS/DFS/RFS (HR 1.93, 95% CI 1.68–2.22; P < .001), and complete response (odds ratio [OR] 0.49, 95% CI 0.36–0.66; P < .001). Patients with a low CXI had a lower body mass index (mean difference [MD] −0.75, 95% CI −1.00 to 0.50; P < .001), skeletal muscle index (standardized MD −0.80, 95% CI −0.98 to −0.61; P < .001), and serum albumin level (MD −0.23, 95% CI −0.26 to −0.20; P < .001); and a higher neutrophil–lymphocyte ratio (MD 1.88, 95% CI 1.29–2.47; P < .001) and more advanced disease stages (OR 0.80, 95% CI 0.71–0.91; P = .001). Conclusion A low CXI was found to be associated with poor survival in patients with cancer. While the CXI is a promising marker for predicting cancer cachexia, further studies are required to verify its usefulness.