The profound ability of human IgA to activate PMNs has been demonstrated for tumor-relevant antigens, such as EpCAM (14), HLA class II (17), carcinoembryonic antigen (18), CD20 (15), epidermal growth factor receptor (EGFR) (12), and human EGFR 2 (HER2) (19), CD38 (20), and GD2 (21, 22). This evidence concerns the gene ERBB2 and neoplasm.