The application of CA72-4 in the diagnosis, prognosis, and treatment of gastric cancer.

The role of conventional serum tumor marker, carbohydrate antigen 72-4 (CA72-4), in assisting diagnosis, monitoring dynamic progression, and evaluating the prognosis of gastric cancer (GC) should not be ignored, especially in the Chinese population. Even though CA72-4 has been used in clinical practice for decades, its modest positivity rate, sensitivity, and specificity did not meet the high demand of the clinical application. However, over the years, some progress in the functions of CA72-4 has been achieved, suggesting that CA72-4 can still be considered a promising marker in oncology. As a biomarker, CA72-4 can achieve improved sensitivity (SEN) and specificity (SPE) when combined with other biomarkers, selecting suitable reference values, improving detection techniques, and identifying the risk threshold. As a predictor, elevated serum CA72-4 levels were found to be significantly associated with prognostic risk factors, further assessing therapeutic validity and resectability. Recently, an effective method to reduce the toxicity of CA72-4 targeted therapy has been developed. Moreover, CA72-4 could induce novel aptamers to react with tumor cells and enhance the efficacy of trastuzumab in HER2-positive GC. Therefore, in this review, we discuss the most recent application of CA72-4 in the diagnosis, prognosis, and treatment of GC.