Prognostic Significance of Sarcopenia in Colorectal Cancer: A Review of Clinical Evidence

Background: Colorectal cancer (CRC) is one of the most common and deadly malignancies worldwide. Sarcopenia, defined as a progressive loss of skeletal muscle mass and function, has recently been recognized as an important prognostic factor in CRC, influencing both postoperative complications and long-term survival. Methods: We conducted a descriptive review of 18 clinical studies investigating the association between sarcopenia and CRC across stages I-IV. Sarcopenia was primarily assessed using computed tomography-derived skeletal muscle index (SMI) or psoas index (PI) at the lumbar vertebrae (L3/L4), with some studies additionally incorporating muscle strength and performance. Results: The prevalence of sarcopenia among CRC patients ranged from 12% to 60%. Most studies reported higher risks of postoperative complications in sarcopenic patients. For instance, Peng et al demonstrated an increased risk of complications in stage IV CRC patients with sarcopenia (OR: 3.12, 95% CI: 1.14-8.49). Regarding survival, sarcopenia was consistently associated with worse overall survival (OS), disease-free survival (DFS), and recurrence-free survival (RFS). Brown et al (2018) showed that deterioration in muscle mass and radiodensity significantly predicted poorer OS in 1,924 stage I-III CRC patients (HR: 2.15, 95% CI: 1.59-2.92). However, several studies reported no significant associations. Conclusion: Sarcopenia is prevalent in CRC patients and strongly correlates with both short-term surgical outcomes and long-term prognosis. However, current evidence is mainly derived from heterogeneous observational studies, and further prospective studies are needed before sarcopenia assessment can be translated into routine clinical practice.