Ovarian Cancer accounts for 33% of gynecological malignancies but causes 55% of gynecologic cancer deaths. Eighty-five to ninety percent of ovarian cancers of the epithelial cell type. The overall theme of this Program project (renewal of CA52477) is to: 1) perform histochemical, biochemical and molecular studies to improve our understanding of the biology of epithelial ovarian cancer, 2) conduct clinical trials in newly diagnosed and persistent/recurrent ovarian cancer using novel chemotherapeutic approaches, and 3) investigate the efficacy the efficacy and safety of immunotherapy using radiolabeled monoclonal antibodies and polyvalent vaccines. The general theme will be achieved through three separate projects with the support of four cores in a Program Project that has been designed to maximize existing collaborations and to develop new collaborations. The effective multi-disciplinary collaboration addressing a single disease will allowed shared resources and will stimulate the development and integration of ideas from different areas of expertise in such a way that the whole will be greater than the sum of the parts. The specific aim of this Program Project in epithelial ovarian cancer is the confirmation of the following hypotheses: 1) intensification of therapy (surgical and chemotherapeutic) can improve survival in a select group of ovarian cancer patients. 2) New types of therapy are necessary for patients who do not achieve a complete response to conventional therapy. 3) Improvements in salvage therapy can be achieved. 4) Immunotherapy using radio-labeled monoclonal antibodies or polyvalent vaccines may be effective adjuvant therapy for patients with minimal residual disease following primary therapy. 5) Analysis of antigenic and molecular markers for epithelial ovarian cancer can improve our understanding of the development of ovarian cancer. 6) Further analyses of ovarian cancer antigens will allow for the development of better antibodies and vaccines for modification of existing antibodies to improve the diagnosis and treatment of ovarian cancer. The superb resources and active support of Memorial Sloan-Kettering Cancer Center provides an ideal setting for this Program Project. The combined expertise of the investigators involved provides ample experience and knowledge to carry out this Project successfully.