INSL5 and nasopharyngeal carcinoma: To determine whether plasma INSL5 could be a prognostic marker for NPC patients, we preformed receiver operating characteristic (ROC) curve analysis to identify the optimum cut‐off value (3.73 ng/ml) for plasma INSL5 level for prognosis analysis and used the Kaplan–Meier test to analyze the correlation between the concentration of INSL5 and patient survival in GZ cohort which is the only one cohort with complete clinical outcome information.