Prevalence of sarcopenia in esophageal cancer patients receiving preoperative neoadjuvant therapy: a systematic review and meta-analysis.

[BACKGROUND] Sarcopenia is a critical comorbidity in esophageal cancer patients undergoing neoadjuvant therapy (NAT), linked to poor surgical outcomes and survival. However, its reported prevalence varies widely, and a comprehensive synthesis of evidence is lacking.

[OBJECTIVE] To systematically evaluate and quantify the prevalence of the sarcopenia disease in in patients known to be diagnosed with esophageal cancer and receiving preoperative neoadjuvant therapy and examine its association with clinical outcomes.

[METHODS] Following PRISMA guidelines 2020, This systematic review and meta-analysis that was registered on PROSPERO (CRD420251109294), provides a comprehensive search through PubMed, SCOPUS, Web of Science, and the Cochrane Library to identify research papers reporting sarcopenia prevalence in esophageal cancer patients undergoing neoadjuvant chemotherapy or chemoradiotherapy. Pooled prevalence estimates and outcome associations were calculated using random-effects models. Subgroup and sensitivity analyses were performed to explore heterogeneity, and study quality was assessed using the Newcastle-Ottawa Scale.

[RESULTS] Twenty-six research studies comprising 3298 patients were included. The pooled prevalence of sarcopenia following neoadjuvant therapy was 48% (95% CI 38-58%), with considerable heterogeneity (I = 95.7%). Sarcopenia was significantly associated with worse overall survival (HR: 2.10; 95% CI 1.72-2.57) but showed no statistically significant association with recurrence-free survival or postoperative complications. Most studies were of moderate to high quality, though differences in diagnostic criteria and assessment timing contributed to heterogeneity.

[CONCLUSIONS] Sarcopenia is highly prevalent among patients with esophageal cancer undergoing neoadjuvant therapy. Although sarcopenia was consistently associated with poorer overall survival, these findings are derived from heterogeneous definitions, variable assessment timing, and unadjusted outcome analyses, and should therefore be interpreted as associative rather than causal. Standardized diagnostic criteria, incorporation of muscle strength assessment, and prospective studies are required in future research.