SPDL1 and non-small cell lung carcinoma: In contrast, for NSCLC patients with high preoperative plasma sPD-L1 and low tcPD-L1 expression, PD-L1-positive TAMs must be responsible for the elevated sPD-L1 level in peripheral blood and also contribute to poor prognosis, given that postoperative RFS tended to be shorter for the high PD-L1-positive TAMs group than for the low PD-L1-positive TAMs group (Fig. 4c).