The aim of this project is to define clinically useful molecular-oriented early detection of minimal disease in ovarian cancer that can identify patients not responding to the standard therapy at the time of surgery. This will eventually lead to alternative therapy modalities, which can bring benefits to this group of patients. Signatures that signal the presence of minimal disease will be systematically investigated at various molecular levels (DNA, RNA, and protein) and in a broad spectrum of biological materials (tumor tissue, circulating and disseminated tumor cells, sera, white blood cells, ascites) from ovarian cancer patients. Profiling of chromosomal loss or gain, gene methylation and mutations, mRNA expression and protein will be analyzed. Specific signatures that predicts patients´ outcome or indicate minimal residual disease, eventually suitable for early primary diagnosis, will be extracted.