Triglyceride-glucose index in predicting gastric cancer prognosis: A need for caution

Gastric cancer (GC) remains one of the leading causes of cancer-related mortality worldwide. Accurate prognostic assessment, which is essential for enhancing overall survival (OS), currently depends on pathologic and clinical staging. This underscores the urgent need for reliable and real-time prognostic biomarkers. The triglyceride-glucose (TyG) index, a readily available marker of insulin resistance, has recently emerged as a potential prognostic tool in GC. Numerous studies have consistently shown a significant association between elevated TyG levels and inferior OS as well as progression-free survival. Despite these promising findings, several challenges must be addressed before the TyG index can be widely adopted in clinical practice. Firstly, the TyG index lacks cancer-specificity, reflecting broader metabolic disturbances commonly observed in conditions such as obesity, diabetes, and cardiovascular disease. This lack of specificity complicates its interpretation in oncological settings. Additionally, the cutoff values for TyG index vary across studies, hindering the establishment of a standardized threshold for clinical application. While the TyG index provides valuable insights into a patient's metabolic health, its limited cancer specificity necessitates cautious use when evaluating the prognosis of GC treatment.