The hybridoma technique for producing monoclonal antibodies developed by Drs. Kohler and Millstein in 1975 revolutionized the field of tumor immunology. It is now clear that there are antigens associated with or restricted to human neoplasms that have biologic significance. Monoclonal antibodies have already been demonstrated to have great immunodiagnostic value, and it is anticipated that they will become a component of our therapeutic armamentarium. Most investigators in the field, however, feel the true potential of monoclonal antibodies in cancer therapy remains to be determined. Clearly...