IGHE and neoplasm: In mice, where it should be noted the human IgE system is not fully recapitulated and expression of the high-affinity IgE receptor (FcεRI) is only present in mast cells and basophils, a carcinogen-induced IgE response was protective against carcinogenesis [12], but conversely an inflammation-driven polyclonal IgE response promoted tumour outgrowth [13].