PLD1 and neoplasm: The data suggested that heterogeneous tumor response to the anti-PLD1 Ab therapy could be attributed to (1) the difference in the expression of PD-L1 protein, (2) the variation in the amount of anti-PD-L1 IgG delivery to tumor cells, (3) the difference in the amount of tumor coagulation inside the tumor, and (4) the difference in the amount of immune cells inside the tumor.