SPDL1 and neoplasm: Similarly, sPD-L1 levels differed by tumor grade, with higher concentrations observed in G2–G3 tumors (7.34 pg/mL; IQR: 4.79–10.19) compared to G1 tumors (5.08 pg/mL; IQR: 3.44–9.19; p = 0.0046) (Table 7, Figure 3).