CD39 was another biomarker to distinguish tumor-reactive TILs from non-tumor-reactive bystander TILs39,40; In addition, the expression of CD103 is associated with increased tumor survival, and double-positive of CD103 and CD8 TILs indicated a better prognostic marker than total CD8 TILs41. The gene discussed is ENTPD1; the disease is neoplasm.