CD4 and familial pancreatic carcinoma: Conversely, other phenotypes, including CD28 on CD45RA− CD4 non‐Treg (OR = 1.155, 1.028–1.297, p = 0.016) and CD25 on activated Treg (OR = 1.180, 1.014–1.374, p = 0.032) within T regulatory cells, exhibited a positive correlation with pancreatic cancer risk [16].