Defining the optimal radiation-induced lymphopenia metric to discern its survival impact in esophageal cancer.

A detrimental association between radiation-induced lymphopenia (RIL) and oncologic outcomes in esophageal cancer patients has been established. However, an optimal metric for RIL remains undefined, but is important for application of this knowledge in clinical decision-making and trial designs. The aim of this study was to find the optimal RIL metric discerning survival.