Immuno-PET of cancer: a revival of antibody imaging.

With the identification of tumorassociated antigens more than 30 y ago and the development of hybridoma technology in 1975, investigators realized that Paul Ehrlich’s vision to effectively target drugs to diseased tissues could be tested. It was shown that monoclonal antibodies could specifically target tumors (1,2), and it was hypothesized that cancer could be treated with naked antibodies by inducing antibody-dependent cellular cytotoxicity, complement-dependent cytotoxicity, or apoptosis or with antibodies tagged with cytotoxic drugs or radionuclides. Indeed, in the early