Emerging role of immune checkpoint inhibitors in the treatment of ovarian cancer.

INTRODUCTION: In recent years, ovarian cancer (OC) treatment has been enriched with many new target therapies, most of all antiangiogenic drugs and PARP inhibitors (PARPis), which have literally changed the natural history of the disease. The impressive results of immunotherapy in other malignancies, mainly melanoma and lung cancer, and the good signals of activity in gynecological neoplasms like cervical and microsatellite instable (MSI-H) endometrial cancer, opened the space to the introduction of immune-stimulatory drugs in ovarian cancer. AREA COVERED: The goal of this article is to summarize the newest evidence on the use of immune check point inhibitors in OC trying to explain why, at present, this strategy has failed to improve clinical outcome and focusing on the possible strategies to overcome treatment failure. EXPERT OPINION: Although numerous trials have been undertaken, only scanty results have been obtained so far with immune check-point inhibitors (ICIs) in OC either when used as single agents or in combination with antiangiogenic therapy and ongoing trials are exploring the association of ICIs with PARPis and other ICIs. A better knowledge of predictive biomarkers of response and mechanisms of immunotherapy resistance, will help in identifying the most appropriate population to treat with ICIs.