The best treatment results for advanced-stage
ovarian cancer patients are obtained with
cytoreductive surgery followed by
combination chemotherapy. However, the 5-year survival rate of only 20% clearly shows a need for new treatment modalities. At present several modes of
immunotherapy for
cancer are being explored such as the use of
monoclonal antibodies, bispecific antibodies, or specific cytotoxic effector cells, all making use of the presence of
tumor-associated
antigens remaining, necessary for
tumor cell recognition. The antigenic phenotype of human
epithelial ovarian cancer after
chemotherapy treatment is an important issue in planning potential immunotherapeutic strategies for
ovarian cancer. Therefore, we compared the
antigen expression in
tumor specimens obtained during operation for primary epithelial ovarian
tumors and tissue biopsies taken during second-look operations after the administration of
combination chemotherapy. A total of 60 ovarian
tumors, including 44 serous, 3 mucinous, 2 endometrioid, 1 clear cell, 6 mixed, 2 undifferentiated, and 2
granulosa cell tumors, was studied. Frozen sections of the
tumor specimens were stained with 15 different
monoclonal antibodies by the indirect immunoperoxidase technique and graded semiquantitatively. The results showed only limited differences in antigenic expression in
tumor tissue obtained before and after
chemotherapy. Because
antigen expression was not altered,
immunotherapy making use of these
antigenic determinants will not be hampered by prior
chemotherapy.