SPDL1 and non-small cell lung carcinoma: These data suggest that among NSCLC patients with high preoperative plasma sPD-L1 levels, those whose plasma sPD-L1 was presumably derived from high tcPD-L1 expression might have a better prognosis after surgery, given that postoperative RFS tended to be longer for the high tcPD-L1 expression group than for the low tcPD-L1 expression group (Fig. 4b).