HOXD13 and neoplasm: Spearman’s correlation analysis showed a significant correlation between the following variables: (a) higher pack-years and greater change in sPD-L1, (b) higher tumor PD-L1 (TPS) and higher post-treatment sPD-L1 and sPD-1, (c) higher tumor PD-L1 and greater change in sPD-1.