The objective of this study was to review studies that have investigated the immune response in the presence of a malignant ovarian neoplasia. A review of the literature was performed to identify studies of malignant ovarian neoplasia, particularly studies that addressed the potential for cytokines, nitric oxide, and lymphocytes to mediate an immune response against ovarian cancer. Certain subsets of tumor-infiltrating leukocytes and/or tumor-associated leukocytes have been found to correlate with an improved disease prognosis, while other lymphocyte subsets (such as CD3+/CD4+/CD25+ T cells) have been associated with a poor prognosis. These data suggest that cytokines can have a protective role, or can promote an immune system defense against a cancer. In particular, certain cytokines (e.g., IL 8, IL 10) represent attractive candidates for the development of new diagnostic, prognostic, and therapeutic strategies for the treatment of ovarian cancer.