CD40LG and cancer: Serum sCD40L levels were definitively different between the cancer and non-cancer groups in both low-CA19-9 and high-CA19-9 groups independent of serum CA19-9 levels (each p < 0.001; data not shown); this means that serum sCD40L can differentiate between PDAC and non-cancer in cases where serum CA19-9 levels were not significantly different between cancer and non-cancer groups.