Early tumor shrinkage( ETS) is defined as the reduction rate of tumor volume evaluated in ear-ly treatment.In recent years,mutiple studies have demonstrated that ETS predicted tumor prognosis well,it can be used as an important predictor of prognosis.Finding a predictor in the early phase of treatment can optimize treat-ment regimens and ameliorate the prognosis of tumor.We summarize the research progress of the relationship be-tween ETS and prognosis.