Epithelial ovarian cancer is the most lethal gynecological malignancy in developed countries and the fifth most common cause of cancer-related death in women. Poor prognosis is due to challenges in early diagnosis and development of inevitable resistance to chemotherapy in majority of patients despite of good initial treatment response. The purpose of this prospective study is to analyze variation in microRNA expression in prediction of primary treatment response and the role of microRNAs in development of chemoresistance in epithelial ovarian cancer.