Monoclonal antibody treatment of solid tumors: a coming of age

Over the past 5 years there has been a renewed interest in the use of monoclonal antibodies and immunoconjugates in the treatment of nonhematologic malignancies. This enthusiasm has stemmed from advances in recombinant technology allowing for the production of chimeric and humanized antibodies, from Food and Drug Administration approval of radioimmunoconjugates for use in diagnosis and staging in colorectal, ovarian, and prostate cancer, from studies demonstrating durable response rates in lymphoma and breast cancer, and from trials demonstrating marked efficacy of radiolabeled antibodies in the treatment of non-Hodgkin's lymphoma. Part of the success of chimeric and humanized antibodies in treating solid tumors relates to the lack of human antimouse antibody formation along with enhanced immunogenic effector mechanisms. The pitfalls underlying early trials of murine monoclonal antibodies in solid tumors and newer antibody approaches using unique antigen targets, bifunctional constructs, and alternative routes of antibody administration will be discussed.