Impact of neoadjuvant chemotherapy on the immune microenvironment in advanced epithelial ovarian cancer: Prognostic and therapeutic implications

Over the last decade, increasing evidence highlights the role of the host immune system in the control of tumor growth and the prognostic implications of tumor infiltrating lymphocytes (TILs) in ovarian cancer. Most data support a better prognosis with accumulation of CD3+ and CD8 + TILs and a poor outcome associated with increased regulatory T cells. However, only a small number of studies have focused on the effect of neoadjuvant chemotherapy (NACT) on the tumor immune microenvironment. This review will provide an update on the prognostic value of TIL subpopulations at diagnosis and a comprehensive overview of the recent studies evaluating the impact of neoadjuvant chemotherapy on TILs and their relationship to clinical outcome in advanced ovarian cancer. This information could help in future investigations of immunotherapy as maintenance following primary treatment.